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-rw-r--r--lib/diameter/doc/src/diameter.xml1435
1 files changed, 1014 insertions, 421 deletions
diff --git a/lib/diameter/doc/src/diameter.xml b/lib/diameter/doc/src/diameter.xml
index 2cad70e3bc..b7669b760b 100644
--- a/lib/diameter/doc/src/diameter.xml
+++ b/lib/diameter/doc/src/diameter.xml
@@ -1,11 +1,22 @@
<?xml version="1.0" encoding="latin1" ?>
-<!DOCTYPE erlref SYSTEM "erlref.dtd">
+<!DOCTYPE erlref SYSTEM "erlref.dtd" [
+ <!ENTITY make_ref
+ '<seealso marker="erts:erlang#make_ref-0">erlang:make_ref/0</seealso>'>
+ <!ENTITY transport_module
+ '<seealso marker="diameter_transport">transport module</seealso>'>
+ <!ENTITY dictionary
+ '<seealso marker="diameter_dict">dictionary</seealso>'>
+ <!ENTITY % also SYSTEM "seealso.ent" >
+ <!ENTITY % here SYSTEM "seehere.ent" >
+ %also;
+ %here;
+]>
<erlref>
<header>
<copyright>
-<year>2011</year>
+<year>2011</year><year>2012</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -43,35 +54,30 @@ under the License.
<description>
<p>
-This module provides the interface with which a user
-creates a service that sends and receives messages using the
-Diameter protocol as defined in RFC 3588.</p>
+This module provides the interface with which a user can
+implement a Diameter node that sends and receives messages using the
+Diameter protocol as defined in &the_rfc;.</p>
<p>
Basic usage consists of creating a representation of a
-locally implemented Diameter peer and its capabilities with <seealso
-marker="#start_service">start_service/2</seealso>, adding transport
-capability using <seealso
-marker="#add_transport">add_transport/2</seealso> and sending Diameter
-requests and receiving Diameter answers with <seealso
-marker="#call">call/4</seealso>.
+locally implemented Diameter node and its capabilities with
+&start_service;, adding transport capability using
+&add_transport; and sending Diameter
+requests and receiving Diameter answers with &call;.
Incoming Diameter requests are communicated as callbacks to a
-<seealso
-marker="diameter_app">diameter_app(3)</seealso> callback modules as
+&man_app; callback modules as
specified in the service configuration.</p>
<p>
-Beware the difference between <em>diameter application</em> and
-<em>Diameter application</em>.
+Beware the difference between <em>diameter</em> (not capitalised) and
+<em>Diameter</em> (capitalised).
The former refers to the Erlang application named diameter whose main
-api is defined here, the latter to an application of the Diameter
-protocol in the sense of RFC 3588.
-More generally, capitalized Diameter refers to the RFC
-and diameter to this implementation.</p>
+api is defined here, the latter to Diameter protocol in the sense of
+&the_rfc;.</p>
<p>
-The diameter application must be started before calling functions in
-this module.</p>
+The diameter application must be started before calling most functions
+in this module.</p>
</description>
@@ -84,13 +90,15 @@ this module.</p>
<tag><c>Address()</c></tag>
<tag><c>DiameterIdentity()</c></tag>
+<tag><c>Grouped()</c></tag>
+<tag><c>OctetString()</c></tag>
<tag><c>Time()</c></tag>
<tag><c>Unsigned32()</c></tag>
<tag><c>UTF8String()</c></tag>
<item>
<p>
-Types corresponding to RFC 3588 AVP Data Formats.
-Defined in <seealso marker="diameter_dict">diameter_dict(4)</seealso>.</p>
+Types corresponding to &the_rfc; AVP Data Formats.
+Defined in &dict_data_types;.</p>
<marker id="application_alias"/>
</item>
@@ -99,31 +107,34 @@ Defined in <seealso marker="diameter_dict">diameter_dict(4)</seealso>.</p>
<item>
<p>
A name identifying a Diameter application in
-service configuration passed to <seealso
-marker="#start_service">start_service/2</seealso> and passed to
-<seealso marker="#call">call/4</seealso> when sending requests
-belonging to the application.</p>
+service configuration.
+Passed to &call; when sending requests
+defined by the application.</p>
<marker id="application_module"/>
</item>
-<tag><c>application_module() = Mod | [Mod | ExtraArgs]</c></tag>
+<tag><c>application_module() = Mod
+ | [Mod | ExtraArgs]
+ | #diameter_callback{}</c></tag>
<item>
-<code>
+<pre>
Mod = atom()
ExtraArgs = list()
-</code>
+</pre>
<p>
-A module implementing the callback interface defined in <seealso
-marker="diameter_app">diameter_app(3)</seealso>, along with any
+A module implementing the callback interface defined in &man_app;,
+along with any
extra arguments to be appended to those documented for the interface.
-Any extra arguments are appended to the documented list of arguments for
-each function.
-Note that additional arguments specific to an outgoing request be
-specified to <seealso marker="#call">call/4</seealso>, in which case
-the call-specific arguments are appended to any specified with the
-callback module.</p>
+Note that extra arguments specific to an outgoing request can be
+specified to &call;, in which case
+those are are appended to any module-specific extra arguments.</p>
+
+<p>
+Specifying a <c>#diameter_callback{}</c> record allows individual
+functions to be configured in place of the usual &man_app; callbacks.
+See that module for details.</p>
<marker id="application_opt"/>
</item>
@@ -132,18 +143,18 @@ callback module.</p>
<item>
<p>
-Options defining a Diameter application as configured in an
-<c>application</c> option passed to
-<seealso marker="#start_service">start_service/2</seealso>.</p>
+Options defining a Diameter application.
+Has one the following types.</p>
<taglist>
-<tag><c>{alias, application_alias()}</c></tag>
+<tag><c>{alias, &application_alias;}</c></tag>
<item>
<p>
An unique identifier for the application in the scope of the
service.
-Optional, defaults to the value of the <c>dictionary</c> option.</p>
+Defaults to the value of the <c>dictionary</c> option if
+unspecified.</p>
</item>
<tag><c>{dictionary, atom()}</c></tag>
@@ -152,47 +163,43 @@ Optional, defaults to the value of the <c>dictionary</c> option.</p>
The name of an encode/decode module for the Diameter
messages defined by the application.
These modules are generated from a specification file whose format is
-documented in <seealso
-marker="diameter_dict">diameter_dict(4)</seealso>.</p>
+documented in &man_dict;.</p>
</item>
-<tag><c>{module, application_module()}</c></tag>
+<tag><c>{module, &application_module;}</c></tag>
<item>
<p>
-A callback module with which messages of the Diameter application are
+The callback module with which messages of the Diameter application are
handled.
-See <seealso marker="diameter_app">diameter_app(3)</seealso> for
-information on the required interface and semantics.</p>
+See &man_app; for the required interface and semantics.</p>
</item>
<tag><c>{state, term()}</c></tag>
<item>
<p>
The initial callback state.
-Defaults to the value of the <c>alias</c> option if unspecified.
-The prevailing state is passed to certain
-<seealso marker="diameter_app">diameter_app(3)</seealso>
-callbacks, which can then return a new state.</p>
+The prevailing state is passed to some
+&man_app;
+callbacks, which can then return a new state.
+Defaults to the value of the <c>alias</c> option if unspecified.</p>
</item>
<tag><c>{call_mutates_state, true|false}</c></tag>
<item>
<p>
-Specifies whether or not the <seealso
-marker="diameter_app#pick_peer">pick_peer/4</seealso>
-application callback (following from a call to
-<seealso marker="#call">call/4</seealso>)
-can modifiy state,
+Specifies whether or not the &app_pick_peer;
+application callback can modify the application state,
Defaults to <c>false</c> if unspecified.</p>
+<note>
<p>
-Note that <seealso
-marker="diameter_app#pick_peer">pick_peer</seealso> callbacks are
-serialized when these are allowed to modify state, which is a
+&app_pick_peer; callbacks
+are serialized when these are allowed to modify state, which is a
potential performance bottleneck.
A simple Diameter client may suffer no ill effects from using mutable
-state but a server or agent that responds to incoming request but
-sending its own requests should probably avoid it.</p>
+state but a server or agent that responds to incoming request should
+probably avoid it.</p>
+</note>
</item>
<tag><c>{answer_errors, callback|report|discard}</c></tag>
@@ -200,18 +207,16 @@ sending its own requests should probably avoid it.</p>
<p>
Determines the manner in which incoming answer messages containing
decode errors are handled.
-If <c>callback</c> then errors result in a <seealso
-marker="diameter_app#handle_answer">handle_answer/4</seealso>
-callback in the same fashion as for <seealso
-marker="diameter_app#handle_request">handle_request/3</seealso>, in the
-<c>errors</c> field of the <c>diameter_packet</c> record passed into
-the callback.
+If <c>callback</c> then errors result in a &app_handle_answer;
+callback in the same fashion as for &app_handle_request;, with
+errors communicated in the <c>errors</c> field of the
+<c>#diameter_packet{}</c> record passed to the callback.
If <c>report</c> then an answer containing errors is discarded
without a callback and a warning report is written to the log.
If <c>discard</c> then an answer containing errors is silently
discarded without a callback.
In both the <c>report</c> and <c>discard</c> cases the return value
-for the <seealso marker="#call">call/4</seealso> invocation in
+for the &call; invocation in
question is as if a callback had taken place and returned
<c>{error, failure}</c>.</p>
@@ -228,8 +233,9 @@ Defaults to <c>report</c> if unspecified.</p>
<item>
<p>
-Options available to <seealso marker="#call">call/4</seealso> when
-sending an outgoing Diameter request.</p>
+Options available to &call; when
+sending an outgoing Diameter request.
+Has one of the following types.</p>
<taglist>
@@ -238,23 +244,23 @@ sending an outgoing Diameter request.</p>
<p>
Extra arguments to append to callbacks to the callback
module in question.
-These are appended to any extra arguments configured with the callback
+These are appended to any extra arguments configured on the callback
itself.
Multiple options append to the argument list.</p>
</item>
-<tag><c>{filter, peer_filter()}</c></tag>
+<tag><c>{filter, &peer_filter;}</c></tag>
<item>
<p>
A filter to apply to the list of available peers before passing them to
-the <seealso marker="diameter_app#pick_peer">pick_peer/4</seealso>
+the &app_pick_peer;
callback for the application in question.
Multiple options are equivalent a single <c>all</c> filter on the
corresponding list of filters.
Defaults to <c>none</c>.</p>
</item>
-<tag><c>{timeout, Unsigned32()}</c></tag>
+<tag><c>{timeout, &dict_Unsigned32;}</c></tag>
<item>
<p>
The number of milliseconds after which the request should
@@ -265,21 +271,17 @@ Defaults to 5000.</p>
<tag><c>detach</c></tag>
<item>
<p>
-Causes <seealso marker="#call">call/4</seealso> to return <c>ok</c> as
+Causes &call; to return <c>ok</c> as
soon as the request in
question has been encoded instead of waiting for and returning
-the result from a subsequent
-<seealso marker="diameter_app#handle_answer">handle_answer/4</seealso>
-or <seealso
-marker="diameter_app#handle_error">handle_error/4</seealso>
-callback.</p>
+the result from a subsequent &app_handle_answer; or
+&app_handle_error; callback.</p>
</item>
</taglist>
<p>
-An invalid option will cause <seealso marker="#call">call/4</seealso>
-to fail.</p>
+An invalid option will cause &call; to fail.</p>
<marker id="capability"/>
</item>
@@ -288,108 +290,54 @@ to fail.</p>
<item>
<p>
-AVP values used in outgoing CER/CEA messages during capabilities exchange.
-Can be configured both on a service and a transport, the latter taking
-precedence over the former.</p>
+AVP values sent in outgoing CER or CEA messages during capabilities
+exchange.
+Can be configured both on a service and a transport, values specified
+on the latter taking precedence over any specified on the former.
+Has one of the following types.</p>
<taglist>
-<tag><c>{'Origin-Host', DiameterIdentity()}</c></tag>
-<item>
-<p>
-Value of the Origin-Host AVP in outgoing messages.</p>
-</item>
-
-<tag><c>{'Origin-Realm', DiameterIdentity()}</c></tag>
+<tag><c>{'Origin-Host', &dict_DiameterIdentity;}</c></tag>
+<tag><c>{'Origin-Realm', &dict_DiameterIdentity;}</c></tag>
+<tag><c>{'Host-IP-Address', [&dict_Address;]}</c></tag>
<item>
<p>
-Value of the Origin-Realm AVP in outgoing messages.</p>
+An address list is available to the start function of a
+&transport_module;, which
+can return a new list for use in the subsequent CER or CEA.
+Host-IP-Address need not be specified if the transport start function
+returns an address list.</p>
</item>
-<tag><c>{'Host-IP-Address', [Address()]}</c></tag>
+<tag><c>{'Vendor-Id', &dict_Unsigned32;}</c></tag>
+<tag><c>{'Product-Name', &dict_UTF8String;}</c></tag>
+<tag><c>{'Origin-State-Id', &dict_Unsigned32;}</c></tag>
<item>
<p>
-Values of Host-IP-Address AVPs.
-Optional.</p>
-
-<p>
-The list of addresses is available to the start function of a
-transport module, which either uses them as is or returns a new list
-(typically as configured as <c>transport_config()</c> on the
-transport module in question) in order for the correct list of
-addresses to be sent in capabilities exchange messages.</p>
-</item>
-
-<tag><c>{'Vendor-Id', Unsigned32()}</c></tag>
-<item>
-<p>
-Value of the Vendor-Id AVP sent in an outgoing capabilities
-exchange message.</p>
-</item>
-
-<tag><c>{'Product-Name', UTF8String()}</c></tag>
-<item>
-<p>
-Value of the Product-Name AVP sent in an outgoing capabilities
-exchange message.</p>
-</item>
-
-<tag><c>{'Origin-State-Id', Unsigned32()}</c></tag>
-<item>
-<p>
-Value of Origin-State-Id to be included in outgoing messages sent by
-diameter itself.
-In particular, the AVP will be included in CER/CEA and DWR/DWA messages.
-Optional.</p>
-
-<p>
+Origin-State-Id is optional but will be included in outgoing messages
+sent by diameter itself: CER/CEA, DWR/DWA and DPR/DPA.
Setting a value of <c>0</c> (zero) is equivalent to not setting a
-value as documented in RFC 3588.
-The function <seealso
-marker="#origin_state_id">origin_state_id/0</seealso>
-can be used as to retrieve a value that is set when the diameter
+value as documented in &the_rfc;.
+The function &origin_state_id;
+can be used as to retrieve a value that is computed when the diameter
application is started.</p>
</item>
-<tag><c>{'Supported-Vendor-Id', [Unsigned32()]}</c></tag>
+<tag><c>{'Supported-Vendor-Id', [&dict_Unsigned32;]}</c></tag>
+<tag><c>{'Auth-Application-Id', [&dict_Unsigned32;]}</c></tag>
+<tag><c>{'Inband-Security-Id', [&dict_Unsigned32;]}</c></tag>
<item>
<p>
-Values of Supported-Vendor-Id AVPs sent in an outgoing
-capabilities exchange message.
-Optional, defaults to the empty list.</p>
+Inband-Security-Id defaults to the empty list, which is equivalent to a
+list containing only 0 (= NO_INBAND_SECURITY).
+If 1 (= TLS) is specified then TLS is selected if the CER/CEA received
+from the peer offers it.</p>
</item>
-<tag><c>{'Auth-Application-Id', [Unsigned32()]}</c></tag>
-<item>
-<p>
-Values of Auth-Application-Id AVPs sent in an outgoing
-capabilities exchange message.
-Optional, defaults to the empty list.</p>
-</item>
-
-<tag><c>{'Acct-Application-Id', [Unsigned32()]}</c></tag>
-<item>
-<p>
-Values of Acct-Application-Id AVPs sent in an outgoing
-capabilities exchange message.
-Optional, defaults to the empty list.</p>
-</item>
-
-<tag><c>{'Vendor-Specific-Application-Id', [Grouped()]}</c></tag>
-<item>
-<p>
-Values of Vendor-Specific-Application-Id AVPs sent in
-an outgoing capabilities exchange message.
-Optional, defaults to the empty list.</p>
-</item>
-
-<tag><c>{'Firmware-Revision', Unsigned32()}</c></tag>
-<item>
-<p>
-Value of the Firmware-Revision AVP sent in an outgoing capabilities
-exchange message.
-Optional.</p>
-</item>
+<tag><c>{'Acct-Application-Id', [&dict_Unsigned32;]}</c></tag>
+<tag><c>{'Vendor-Specific-Application-Id', [&dict_Grouped;]}</c></tag>
+<tag><c>{'Firmware-Revision', &dict_Unsigned32;}</c></tag>
</taglist>
@@ -406,7 +354,7 @@ It is an error to specify duplicate tuples.</p>
An expression that can be evaluated as a function in the following
sense.</p>
-<code>
+<pre>
eval([{M,F,A} | T]) ->
apply(M, F, T ++ A);
eval([[F|A] | T]) ->
@@ -415,17 +363,22 @@ eval([F|A]) ->
apply(F, A);
eval(F) ->
eval([F]).
-</code>
+</pre>
<p>
-Evaluating an evaluable() <c>E</c> on an argument list <c>A</c>
+Applying an <c>&evaluable;</c>
+<c>E</c> to an argument list <c>A</c>
is meant in the sense of <c>eval([E|A])</c>.</p>
+<warning>
<p>
-Beware of using local funs (that is, fun expressions not of the
-form <c>fun Module:Name/Arity</c>) in situations in which the fun is
-not short-lived and code is to be upgraded at runtime since any
-processes retaining such a fun will have a reference to old code.</p>
+Beware of using fun expressions of the form <c>fun Name/Arity</c> in
+situations in which the fun is not short-lived
+and code is to be upgraded at runtime since any processes retaining
+such a fun will have a reference to old code.
+In particular, such a value is typically inappropriate in
+configuration passed to &start_service; or &add_transport;.</p>
+</warning>
<marker id="peer_filter"/>
</item>
@@ -433,10 +386,8 @@ processes retaining such a fun will have a reference to old code.</p>
<tag><c>peer_filter() = term()</c></tag>
<item>
<p>
-A filter passed to <seealso marker="#call">call/4</seealso>
-in order to select candidate peers for a
-<seealso marker="diameter_app#pick_peer">pick_peer/4</seealso>
-callback.
+A filter passed to &call; in order to select candidate peers for a
+&app_pick_peer; callback.
Has one of the following types.</p>
<taglist>
@@ -467,63 +418,73 @@ or any peer if the request does not contain
a <c>Destination-Realm</c> AVP.</p>
</item>
-<tag><c>{host, any|DiameterIdentity()}</c></tag>
+<tag><c>{host, any|&dict_DiameterIdentity;}</c></tag>
<item>
<p>
Matches only those peers whose <c>Origin-Host</c> has the
specified value, or all peers if the atom <c>any</c>.</p>
</item>
-<tag><c>{realm, any|DiameterIdentity()</c></tag>
+<tag><c>{realm, any|&dict_DiameterIdentity;</c></tag>
<item>
<p>
Matches only those peers whose <c>Origin-Realm</c> has the
-value, or all peers if the atom <c>any</c>.</p>
+specified value, or all peers if the atom <c>any</c>.</p>
</item>
-<tag><c>{eval, evaluable()}</c></tag>
+<tag><c>{eval, &evaluable;}</c></tag>
<item>
<p>
-Matches only those peers for which the specified evaluable() returns
+Matches only those peers for which the specified
+<c>&evaluable;</c> returns
<c>true</c> on the connection's <c>diameter_caps</c> record.
Any other return value or exception is equivalent to <c>false</c>.</p>
</item>
-<tag><c>{neg, peer_filter()}</c></tag>
+<tag><c>{neg, &peer_filter;}</c></tag>
<item>
<p>
Matches only those peers not matched by the specified filter.</p>
</item>
-<tag><c>{all, [peer_filter()]}</c></tag>
+<tag><c>{all, [&peer_filter;]}</c></tag>
<item>
<p>
-Matches only those peers matched by each filter of the specified list.</p>
+Matches only those peers matched by each filter in the specified list.</p>
</item>
-<tag><c>{any, [peer_filter()]}</c></tag>
+<tag><c>{any, [&peer_filter;]}</c></tag>
<item>
<p>
-Matches only those peers matched by at least one filter of the
+Matches only those peers matched by at least one filter in the
specified list.</p>
</item>
</taglist>
<p>
-Note that the <c>host</c> and <c>realm</c> filters examine the
-outgoing request as passed to <seealso marker="#call">call/4</seealso>,
-assuming that this is a record- or list-valued message() as documented
-in <seealso marker="diameter_app">diameter_app(3)</seealso>, and that
-the message contains at most one of each AVP.
-If this is not the case then the <c>{host|realm, DiameterIdentity()}</c>
+An invalid filter is equivalent to <c>{any,[]}</c>, a filter
+that matches no peer.</p>
+
+<note>
+<p>
+The <c>host</c> and <c>realm</c> filters examine the
+outgoing request as passed to &call;,
+assuming that this is a record- or list-valued <c>&codec_message;</c>,
+and that the message contains at most one of each AVP.
+If this is not the case then the <c>{host|realm, &dict_DiameterIdentity;}</c>
filters must be used to achieve the desired result.
-Note also that an empty host/realm (which should not be typical)
-is equivalent to an unspecified one for the purposes of filtering.</p>
+An empty <c>&dict_DiameterIdentity;</c>
+(which should not be typical)
+matches all hosts/realms for the purposes of filtering.</p>
+</note>
+<warning>
<p>
-An invalid filter is equivalent to <c>{any, []}</c>, a filter
-that matches no peer.</p>
+A <c>host</c> filter is not typically desirable when setting
+Destination-Host since it will remove peer agents from the
+candidates list.</p>
+</warning>
<marker id="service_event"/>
</item>
@@ -531,41 +492,52 @@ that matches no peer.</p>
<tag><c>service_event() = #diameter_event{}</c></tag>
<item>
<p>
-Event message sent to processes that have subscribed using <seealso
-marker="#subscribe">subscribe/1</seealso>.</p>
+An event message sent to processes that have subscribed to these using
+&subscribe;.</p>
<p>
-The <c>info</c> field of the event record can be one of the
-following.</p>
+The <c>info</c> field of the event record can have one of the
+following types.</p>
<taglist>
+<tag><c>start</c></tag>
+<tag><c>stop</c></tag>
+
+<item>
+<p>
+The service is being started or stopped.
+No event precedes a <c>start</c> event.
+No event follows a <c>stop</c> event and this event
+implies the termination of all transport processes.</p>
+</item>
+
<tag><c>{up, Ref, Peer, Config, Pkt}</c></tag>
<tag><c>{up, Ref, Peer, Config}</c></tag>
<tag><c>{down, Ref, Peer, Config}</c></tag>
<item>
-<code>
-Ref = transport_ref()
-Peer = diameter_app:peer()
-Config = {connect|listen, [transport_opt()]}
+<pre>
+Ref = &transport_ref;
+Peer = &app_peer;
+Config = {connect|listen, [&transport_opt;]}
Pkt = #diameter_packet{}
-</code>
+</pre>
<p>
-Reports that the RFC 3539 watchdog state machine has
-transitioned into (<c>up</c>) or out of (<c>down</c>) the open
+The RFC 3539 watchdog state machine has
+transitioned into (<c>up</c>) or out of (<c>down</c>) the OKAY
state.
-If a <c>diameter_packet</c> record is present in an <c>up</c> tuple
-then there has been an exchange of capabilities exchange messages and
-the record contains the received CER or CEA, otherwise the
-connection has reestablished without the loss or transport
+If a <c>#diameter_packet{}</c> record is present in an <c>up</c> event
+then there has been a capabilties exchange on a newly established
+transport connection and the record contains the received CER or CEA.
+Otherwise a connection has reestablished without the loss or
connectivity.</p>
<p>
-Note that a single up/down event for a given peer corresponds to
-as many peer_up/down callbacks as there are Diameter
-applications shared by the peer, as determined during capablilities
-exchange.
+Note that a single <c>up</c>/<c>down</c> event for a given peer
+corresponds to one &app_peer_up;/&app_peer_down;
+callback for each of the Diameter applications negotiated during
+capablilities exchange.
That is, the event communicates connectivity with the
peer as a whole while the callbacks communicate connectivity with
respect to individual Diameter applications.</p>
@@ -573,23 +545,133 @@ respect to individual Diameter applications.</p>
<tag><c>{reconnect, Ref, Opts}</c></tag>
<item>
-<code>
-Ref = transport_ref()
-Opts = [transport_opt()]
-</code>
+<pre>
+Ref = &transport_ref;
+Opts = [&transport_opt;]
+</pre>
<p>
A connecting transport is attempting to establish/reestablish a
-transport connection with a peer following <c>reconnect_timer</c> or
-<c>watchdog_timer</c> expiry.</p>
+transport connection with a peer following &reconnect_timer; or
+&watchdog_timer; expiry.</p>
+</item>
+
+<tag><c>{closed, Ref, Reason, Config}</c></tag>
+<item>
+<pre>
+Ref = &transport_ref;
+Config = {connect|listen, [&transport_opt;]}
+</pre>
+
+<p>
+Capabilities exchange has failed.
+<c>Reason</c> can have one of the following types.</p>
+
+<taglist>
+
+<tag><c>{'CER', Result, Caps, Pkt}</c></tag>
+<item>
+<pre>
+Result = ResultCode | {capabilities_cb, CB, ResultCode|discard}
+Caps = #diameter_caps{}
+Pkt = #diameter_packet{}
+ResultCode = integer()
+CB = &evaluable;
+</pre>
+
+<p>
+An incoming CER has been answered with the indicated result code or
+discarded.
+<c>Caps</c> contains pairs of values for the the local node and remote
+peer.
+<c>Pkt</c> contains the CER in question.
+In the case of rejection by a capabilities callback, the tuple
+contains the rejecting callback.</p>
+</item>
+
+<tag><c>{'CER', Caps, {ResultCode, Pkt}}</c></tag>
+<item>
+<pre>
+ResultCode = integer()
+Caps = #diameter_caps{}
+Pkt = #diameter_packet{}
+</pre>
+
+<p>
+An incoming CER contained errors and has been answered with the
+indicated result code.
+<c>Caps</c> contains only values for the the local node.
+<c>Pkt</c> contains the CER in question.</p>
+</item>
+
+<tag><c>{'CER', timeout}</c></tag>
+<item>
+<p>
+An expected CER was not received within &capx_timeout; of
+connection establishment.</p>
+</item>
+
+<tag><c>{'CEA', Result, Caps, Pkt}</c></tag>
+<item>
+<pre>
+Result = integer() | atom() | {capabilities_cb, CB, ResultCode|discard}
+Caps = #diameter_caps{}
+Pkt = #diameter_packet{}
+ResultCode = integer()
+</pre>
+
+<p>
+An incoming CEA has been rejected for the indicated reason.
+An integer-valued <c>Result</c> indicates the result code sent
+by the peer.
+<c>Caps</c> contains pairs of values for the the local node and remote
+peer.
+<c>Pkt</c> contains the CEA in question.
+In the case of rejection by a capabilities callback, the tuple
+contains the rejecting callback.</p>
+</item>
+
+<tag><c>{'CEA', Caps, Pkt}</c></tag>
+<item>
+<pre>
+Caps = #diameter_caps{}
+Pkt = #diameter_packet{}
+</pre>
+
+<p>
+An incoming CEA contained errors and has been rejected.
+<c>Caps</c> contains only values for the the local node.
+<c>Pkt</c> contains the CEA in question.</p>
+</item>
+
+<tag><c>{'CEA', timeout}</c></tag>
+<item>
+<p>
+An expected CEA was not received within &capx_timeout;
+of connection establishment.</p>
+</item>
+
+</taglist>
+</item>
+
+<tag><c>{watchdog, Ref, PeerRef, {From, To}, Config}</c></tag>
+<item>
+<pre>
+Ref = &transport_ref;
+PeerRef = &app_peer_ref;
+From, To = initial | okay | suspect | down | reopen
+Config = {connect|listen, [transport_opt()]}
+</pre>
+
+<p>
+An RFC 3539 watchdog state machine has changed state.</p>
</item>
</taglist>
<p>
For forward compatibility, a subscriber should be prepared to receive
-<c>diameter_event.info</c> of forms other than those documented
-above.</p>
+info fields of forms other than the above.</p>
<marker id="service_name"/>
</item>
@@ -597,12 +679,11 @@ above.</p>
<tag><c>service_name() = term()</c></tag>
<item>
<p>
-The name of a service as passed to <seealso
-marker="#start_service">start_service/2</seealso> and with which the
+The name of a service as passed to &start_service; and with which the
service is identified.
There can be at most one service with a given name on a given node.
-Note that <c>erlang:make_ref/0</c> can be used to generate a service name
-that is somewhat unique.</p>
+Note that &make_ref;
+can be used to generate a service name that is somewhat unique.</p>
<marker id="service_opt"/>
</item>
@@ -610,29 +691,80 @@ that is somewhat unique.</p>
<tag><c>service_opt()</c></tag>
<item>
<p>
-Options accepted by <seealso
-marker="#start_service">start_service/2</seealso>.
-Can be any <c>capability()</c> tuple as
-well as the following.</p>
+An option passed to &start_service;.
+Can be any <c>&capability;</c> as well as the following.</p>
<taglist>
-<tag><c>{application, [application_opt()]}</c></tag>
+<tag><c>{application, [&application_opt;]}</c></tag>
<item>
<p>
Defines a Diameter application supported by the service.</p>
<p>
-A service must define one application for each Diameter application it
-intends to support.
-For an outgoing Diameter request, the application is specified by
-passing the desired application's <c>application_alias()</c> to
-<seealso marker="#call">call/4</seealso>, while for an
+A service must configure one tuple for each Diameter
+application it intends to support.
+For an outgoing Diameter request, the relevant <c>&application_alias;</c> is
+passed to &call;, while for an
incoming request the application identifier in the message
-header determines the application (and callback module), the
-application identifier being specified in the <seealso
-marker="diameter_dict">dictionary</seealso> file defining the
-application.</p>
+header determines the application, the identifier being specified in
+the application's &dictionary; file.</p>
+</item>
+
+<tag><c>{restrict_connections, false
+ | node
+ | nodes
+ | [node()]
+ | evaluable()}</c></tag>
+<item>
+<p>
+Specifies the degree to which multiple transport connections to the
+same peer are accepted by the service.</p>
+
+<p>
+If type <c>[node()]</c> then a connection is rejected if another already
+exists on any of the specified nodes.
+Values of type <c>false</c>, <c>node</c>, <c>nodes</c> or
+&evaluable; are equivalent to
+values <c>[]</c>, <c>[node()]</c>, <c>[node()|nodes()]</c> and the
+evaluated value, respectively, evaluation of each expression taking
+place whenever a new connection is to be established.
+Note that <c>false</c> allows an unlimited number of connections to be
+established with the same peer.</p>
+
+<p>
+Multiple connections are independent and governed
+by their own peer and watchdog state machines.</p>
+
+<p>
+Defaults to <c>nodes</c>.</p>
+</item>
+
+<tag><c>{sequence, {H,N} | &evaluable;}</c></tag>
+<item>
+<p>
+Specifies a constant value <c>H</c> for the topmost <c>32-N</c> bits of
+of 32-bit End-to-End and Hop-by-Hop identifiers generated
+by the service, either explicity or as a return value of a function
+to be evaluated at &start_service;.
+In particular, an identifier <c>Id</c> is mapped to a new identifier
+as follows.</p>
+<pre>
+(H bsl N) bor (Id band ((1 bsl N) - 1))
+</pre>
+<p>
+Note that &the_rfc; requires that End-to-End identifiers remain unique
+for a period of at least 4 minutes and that this and the call rate
+places a lower bound on the appropriate values of <c>N</c>:
+at a rate of <c>R</c> requests per second an <c>N</c>-bit counter
+traverses all of its values in <c>(1 bsl N) div (R*60)</c> minutes so
+the bound is <c>4*R*60 =&lt; 1 bsl N</c>.</p>
+
+<p><c>N</c> must lie in the range <c>0..32</c> and <c>H</c> must be a
+non-negative integer less than <c>1 bsl (32-N)</c>.</p>
+
+<p>
+Defaults to <c>{0,32}</c>.</p>
</item>
</taglist>
@@ -643,126 +775,312 @@ application.</p>
<tag><c>transport_opt()</c></tag>
<item>
<p>
-Options accepted by <seealso
-marker="#add_transport">add_transport/2</seealso>.</p>
+An option passed to &add_transport;.
+Has one of the following types.</p>
<taglist>
-<tag><c>{transport_module, atom()}</c></tag>
+<marker id="applications"/>
+<tag><c>{applications, [&application_alias;]}</c></tag>
<item>
<p>
-A module implementing a transport process as defined in <seealso
-marker="diameter_transport">diameter_transport(3)</seealso>.
-Defaults to <c>diameter_tcp</c> if unspecified.</p>
+The list of Diameter applications to which the transport should be
+restricted.
+Defaults to all applications configured on the service in question.
+Applications not configured on the service in question are ignored.</p>
+</item>
+
+<marker id="capabilities"/>
+<tag><c>{capabilities, [&capability;]}</c></tag>
+<item>
+<p>
+AVP's used to construct outgoing CER/CEA messages.
+Values take precedence over any specified on the service in
+question.</p>
<p>
-The interface required of a transport module is documented in <seealso
-marker="diameter_transport">diameter_transport(3)</seealso>.</p>
+Specifying a capability as a transport option
+may be particularly appropriate for Inband-Security-Id, in case
+TLS is desired over TCP as implemented by &man_tcp;.</p>
</item>
-<tag><c>{transport_config, term()}</c></tag>
+<marker id="capabilities_cb"/>
+<tag><c>{capabilities_cb, &evaluable;}</c></tag>
<item>
<p>
-A term passed as the third argument to the <seealso
-marker="diameter_transport#start">start/3</seealso> function of
-the relevant <c>transport_module</c> in order to start a transport process.
-Defaults to the empty list if unspecified.</p>
+A callback invoked upon reception of CER/CEA during capabilities
+exchange in order to ask whether or not the connection should
+be accepted.
+Applied to the <c>&transport_ref;</c> and
+<c>#diameter_caps{}</c> record of the connection.</p>
+
+<p>
+The return value can have one of the following types.</p>
+
+<taglist>
+<tag><c>ok</c></tag>
+<item>
+<p>
+Accept the connection.</p>
</item>
-<tag><c>{applications, [application_alias()]}</c></tag>
+<tag><c>integer()</c></tag>
<item>
<p>
-The list of Diameter applications to which usage of the transport
-should be restricted.
-Defaults to all applications configured on the service
-in question.</p>
+Causes an incoming CER to be answered with the specified Result-Code.</p>
</item>
-<tag><c>{capabilities, [capability()]}</c></tag>
+<tag><c>discard</c></tag>
<item>
<p>
-AVP's used to construct outgoing CER/CEA messages.
-Any AVP specified takes precedence over a corresponding value specified
-for the service in question.</p>
+Causes an incoming CER to be discarded without CEA being sent.</p>
</item>
-<tag><c>{watchdog_timer, TwInit}</c></tag>
+<tag><c>unknown</c></tag>
<item>
-<code>
-TwInit = Unsigned32()
- | {M,F,A}
-</code>
+<p>
+Equivalent to returning <c>3010</c>, DIAMETER_UNKNOWN_PEER.</p>
+</item>
+</taglist>
<p>
-The RFC 3539 watchdog timer.
-An integer value is interpreted as the RFC's TwInit in milliseconds,
-a jitter of &plusmn; 2 seconds being added at each rearming of the
-timer to compute the RFC's Tw.
-An MFA is expected to return the RFC's Tw directly, with jitter
-applied, allowing the jitter calculation to be performed by
-the callback.</p>
+Returning anything but <c>ok</c> or a 2xxx series result
+code causes the transport connection to be broken.
+Multiple &capabilities_cb;
+options can be specified, in which
+case the corresponding callbacks are applied until either all return
+<c>ok</c> or one does not.</p>
+</item>
+<marker id="capx_timeout"/>
+<tag><c>{capx_timeout, &dict_Unsigned32;}</c></tag>
+<item>
<p>
-An integer value must be at least 6000 as required by RFC 3539.
-Defaults to 30000 if unspecified.</p>
+The number of milliseconds after which a transport process having an
+established transport connection will be terminated if the expected
+capabilities exchange message (CER or CEA) is not received from the peer.
+For a connecting transport, the timing reconnection attempts is
+governed by &watchdog_timer; or
+&reconnect_timer; expiry.
+For a listening transport, the peer determines the timing.</p>
+
+<p>
+Defaults to 10000.</p>
+</item>
+
+<marker id="disconnect_cb"/>
+<tag><c>{disconnect_cb, &evaluable;}</c></tag>
+
+<item>
+<p>
+A callback invoked prior to terminating the transport process of a
+transport connection having watchdog state <c>OKAY</c>.
+Applied to <c>Reason=transport|service|application</c> and the
+<c>&transport_ref;</c> and
+<c>&app_peer;</c>
+in question, <c>Reason</c> indicating whether the the diameter
+application is being stopped, the service in question is being stopped
+at &stop_service; or
+the transport in question is being removed at &remove_transport;,
+respectively.</p>
+
+<p>
+The return value can have one of the following types.</p>
+
+<taglist>
+<tag><c>{dpr, [option()]}</c></tag>
+<item>
+<p>
+Causes Disconnect-Peer-Request to be sent to the peer, the transport
+process being terminated following reception of
+Disconnect-Peer-Answer or timeout.
+An <c>option()</c> can be one of the following.</p>
+
+<taglist>
+<tag><c>{cause, 0|rebooting|1|busy|2|goaway}</c></tag>
+<item>
+<p>
+The Disconnect-Cause to send, <c>REBOOTING</c>, <c>BUSY</c> and
+<c>DO_NOT_WANT_TO_TALK_TO_YOU</c> respectively.
+Defaults to <c>rebooting</c> for <c>Reason=service|application</c> and
+<c>goaway</c> for <c>Reason=transport</c>.</p>
+</item>
+
+<tag><c>{timeout, &dict_Unsigned32;}</c></tag>
+<item>
+<p>
+The number of milliseconds after which the transport process is
+terminated if DPA has not been received.
+Defaults to 1000.</p>
+</item>
+</taglist>
+</item>
+
+<tag><c>dpr</c></tag>
+<item>
+<p>
+Equivalent to <c>{dpr, []}</c>.</p>
+</item>
+
+<tag><c>close</c></tag>
+<item>
+<p>
+Causes the transport process to be terminated without
+Disconnect-Peer-Request being sent to the peer.</p>
</item>
+<tag><c>ignore</c></tag>
+<item>
+<p>
+Equivalent to not having configured the callback.</p>
+</item>
+</taglist>
+
+<p>
+Multiple &disconnect_cb;
+options can be specified, in which
+case the corresponding callbacks are applied until one of them returns
+a value other than <c>ignore</c>.
+All callbacks returning <c>ignore</c> is equivalent to not having
+configured them.</p>
+
+<p>
+Defaults to a single callback returning <c>dpr</c>.</p>
+</item>
+
+<marker id="reconnect_timer"/>
<tag><c>{reconnect_timer, Tc}</c></tag>
<item>
-<code>
-Tc = Unsigned32()
-</code>
+<pre>
+Tc = &dict_Unsigned32;
+</pre>
<p>
-For a connecting transport, the RFC 3588 Tc timer, in milliseconds.
-Note that this timer determines the frequency with which the transport
+For a connecting transport, the &the_rfc; Tc timer, in milliseconds.
+Note that this timer determines the frequency with which a transport
will attempt to establish a connection with its peer only <em>before</em>
an initial connection is established: once there is an initial
-connection it's watchdog_timer that determines the frequency of
-reconnection attempts, as required by RFC 3539.</p>
+connection it's &watchdog_timer; that determines the
+frequency of reconnection attempts, as required by RFC 3539.</p>
<p>
For a listening transport, the timer specifies the time after which a
previously connected peer will be forgotten: a connection after this time is
regarded as an initial connection rather than a reestablishment,
-causing the RFC 3539 state machine to pass to state OPEN rather than
+causing the RFC 3539 state machine to pass to state OKAY rather than
REOPEN.
-Note that these semantics are not goverened by the RFC and
-that a listening transport's reconnect_timer should be greater than its
-peers's Tc plus jitter.</p>
+Note that these semantics are not governed by the RFC and
+that a listening transport's &reconnect_timer; should be greater
+than its peer's Tw plus jitter.</p>
<p>
Defaults to 30000 for a connecting transport and 60000 for a listening
transport.</p>
</item>
+<marker id="transport_config"/>
+<tag><c>{transport_config, term()}</c></tag>
+<tag><c>{transport_config, term(), &dict_Unsigned32;}</c></tag>
+<item>
+<p>
+A term passed as the third argument to the &transport_start; function of
+the relevant &transport_module; in order to
+start a transport process.
+Defaults to the empty list if unspecified.</p>
+
+<p>
+The 3-tuple form additionally specifies an interval, in milliseconds,
+after which a started transport process should be terminated if it has
+not yet established a connection.
+For example, the following options on a connecting transport
+request a connection with one peer over SCTP or another
+(typically the same) over TCP.</p>
+
+<pre>
+{transport_module, diameter_sctp}
+{transport_config, SctpOpts, 5000}
+{transport_module, diameter_tcp}
+{transport_config, TcpOpts}
+</pre>
+
+<p>
+To listen on both SCTP and TCP, define one transport for each.</p>
+</item>
+
+<marker id="transport_module"/>
+<tag><c>{transport_module, atom()}</c></tag>
+<item>
+<p>
+A module implementing a transport process as defined in &man_transport;.
+Defaults to <c>diameter_tcp</c> if unspecified.</p>
+
+<p>
+Multiple <c>transport_module</c> and &transport_config;
+options are allowed.
+The order of these is significant in this case (and only in this case),
+a <c>transport_module</c> being paired with the first
+&transport_config;
+following it in the options list, or the default value for trailing
+modules.
+Transport starts will be attempted with each of the
+modules in order until one establishes a connection within the
+corresponding timeout (see below) or all fail.</p>
+</item>
+
+<marker id="watchdog_timer"/>
+<tag><c>{watchdog_timer, TwInit}</c></tag>
+<item>
+<pre>
+TwInit = &dict_Unsigned32;
+ | {M,F,A}
+</pre>
+
+<p>
+The RFC 3539 watchdog timer.
+An integer value is interpreted as the RFC's TwInit in milliseconds,
+a jitter of &plusmn; 2 seconds being added at each rearming of the
+timer to compute the RFC's Tw.
+An MFA is expected to return the RFC's Tw directly, with jitter
+applied, allowing the jitter calculation to be performed by
+the callback.</p>
+
+<p>
+An integer value must be at least 6000 as required by RFC 3539.
+Defaults to 30000 if unspecified.</p>
+</item>
+
</taglist>
<p>
Unrecognized options are silently ignored but are returned unmodified
-by <seealso
-marker="#service_info">service_info/2</seealso> and can be referred to
-in predicate functions passed to <seealso
-marker="#remove_transport">remove_transport/2</seealso>.</p>
+by &service_info; and can be referred to
+in predicate functions passed to &remove_transport;.</p>
+
+<marker id="transport_ref"/>
+</item>
+<tag><c>transport_ref() = reference()</c></tag>
+<item>
+<p>
+An reference returned by &add_transport; that
+identifies the configuration.</p>
</item>
</taglist>
</section>
-<marker id="add_transport"/>
<funcs>
<!-- ===================================================================== -->
<func>
-<name>add_transport(SvcName, {connect|listen, Options})
+<name>add_transport(SvcName, {connect|listen, [Opt]})
-> {ok, Ref} | {error, Reason}</name>
<fsummary>Add transport capability to a service.</fsummary>
<type>
-<v>SvcName = service_name()</v>
-<v>Options = [transport_opt()]</v>
-<v>Ref = ref()</v>
+<v>SvcName = &service_name;</v>
+<v>Opt = &transport_opt;</v>
+<v>Ref = &transport_ref;</v>
<v>Reason = term()</v>
</type>
<desc>
@@ -770,8 +1088,8 @@ marker="#remove_transport">remove_transport/2</seealso>.</p>
Add transport capability to a service.</p>
<p>
-The service will start a transport process(es) in order to establish a
-connection with the peer, either by connecting to the peer
+The service will start transport processes as required in order to
+establish a connection with the peer, either by connecting to the peer
(<c>connect</c>) or by accepting incoming connection requests
(<c>listen</c>).
A connecting transport establishes transport connections with at most
@@ -781,84 +1099,77 @@ one peer, an listening transport potentially with many.</p>
The diameter application takes responsibility for exchanging
CER/CEA with the peer.
Upon successful completion of capabilities exchange the service
-calls each relevant application module's <seealso
-marker="diameter_app#peer_up">peer_up/3</seealso> callback
+calls each relevant application module's &app_peer_up; callback
after which the caller can exchange Diameter messages with the peer over
the transport.
In addition to CER/CEA, the service takes responsibility for the
-handling of DWR/DWA and required by RFC 3539 as well as for DPR/DPA.</p>
+handling of DWR/DWA and required by RFC 3539, as well as for DPR/DPA.</p>
<p>
The returned reference uniquely identifies the transport within the
scope of the service.
Note that the function returns before a transport connection has been
-established.
+established.</p>
+
+<note>
+<p>
It is not an error to add a transport to a service that has not yet
been configured: a service can be started after configuring
-transports.</p>
+its transports.</p>
+</note>
-<marker id="call"/>
</desc>
</func>
<!-- ===================================================================== -->
<func>
-<name>call(SvcName, App, Request, Options) -> ok | Answer | {error, Reason}</name>
+<name>call(SvcName, App, Request, [Opt]) -> Answer | ok | {error, Reason}</name>
<fsummary>Send a Diameter request message.</fsummary>
<type>
-<v>SvcName = service_name()</v>
-<v>App = application_alias()</v>
-<v>Request = diameter_app:message() | term()</v>
+<v>SvcName = &service_name;</v>
+<v>App = &application_alias;</v>
+<v>Request = &codec_message;</v>
<v>Answer = term()</v>
-<v>Options = [call_opt()]</v>
+<v>Opt = &call_opt;</v>
</type>
<desc>
<p>
-Send a Diameter request message and possibly return the answer or error.</p>
+Send a Diameter request message.</p>
<p>
-<c>App</c> identifies the Diameter application in which the request is
+<c>App</c> specifies the Diameter application in which the request is
defined and callbacks to the corresponding callback module
-will follow as described below and in <seealso
-marker="diameter_app">diameter_app(3)</seealso>.
-Unless the <c>detach</c> option has been specified to cause an earlier
-return, the call returns either when an answer message is received
-from the peer or an error occurs.
-In the case of an answer, the return value is as returned by a
-<seealso
-marker="diameter_app#handle_answer">handle_answer/4</seealso>
-callback.
-In the case of an error, whether or not the error is returned directly
-by diameter or from a <seealso
-marker="diameter_app#handle_error">handle_error/4</seealso>
+will follow as described below and in &man_app;.
+Unless the <c>detach</c> option is specified, the call returns either
+when an answer message is received from the peer or an error occurs.
+In the answer case, the return value is as returned by a
+&app_handle_answer; callback.
+In the error case, whether or not the error is returned directly
+by diameter or from a &app_handle_error;
callback depends on whether or not the outgoing request is
-successfully encoded for transmission from the peer, the cases being
+successfully encoded for transmission to the peer, the cases being
documented below.</p>
<p>
If there are no suitable peers, or if
-<seealso marker="diameter_app#pick_peer">pick_peer/4</seealso>
-rejects them by returning 'false', then <c>{error, no_connection}</c>
+&app_pick_peer;
+rejects them by returning <c>false</c>, then <c>{error,no_connection}</c>
is returned.
-Otherwise <seealso marker="diameter_app#pick_peer">pick_peer/4</seealso>
-is followed by a
-<seealso
-marker="diameter_app#prepare_request">prepare_request/3</seealso>
-callback, the message is encoded and sent.</p>
+Otherwise &app_pick_peer; is followed by a
+&app_prepare_request; callback, the message is encoded and then sent.</p>
<p>
There are several error cases which may prevent an
answer from being received and passed to a
-<seealso marker="diameter_app#handle_answer">handle_answer/4</seealso>
-callback:</p>
+&app_handle_answer; callback:</p>
<list>
<item>
<p>
If the initial encode of the outgoing request
-fails, then the request process fails and <c>{error, encode}</c>
+fails, then the request process fails and <c>{error,encode}</c>
is returned.</p>
</item>
@@ -866,16 +1177,14 @@ is returned.</p>
<p>
If the request is successfully encoded and sent but
the answer times out then a
-<seealso marker="diameter_app#handle_error">handle_error/4</seealso>
-callback takes place with <c>Reason = timeout</c>.</p>
+&app_handle_error; callback takes place with <c>Reason = timeout</c>.</p>
</item>
<item>
<p>
If the request is successfully encoded and sent but the service in
question is stopped before an answer is received then a
-<seealso marker="diameter_app#handle_error">handle_error/4</seealso>
-callback takes place <c>Reason = cancel</c>.</p>
+&app_handle_error; callback takes place with <c>Reason = cancel</c>.</p>
</item>
<item>
@@ -884,25 +1193,18 @@ If the transport connection with the peer goes down after the request
has been sent but before an answer has been received then an attempt
is made to resend the request to an alternate peer.
If no such peer is available, or if the subsequent
-<seealso marker="diameter_app#pick_peer">pick_peer/4</seealso>
-callback rejects the candidates, then a
-<seealso marker="diameter_app#handle_error">handle_error/4</seealso>
-callback takes place with <c>Reason = failover</c>.
-If a peer is selected then a
-<seealso
-marker="diameter_app#prepare_retransmit">prepare_retransmit/3</seealso>
+&app_pick_peer; callback rejects the candidates, then a
+&app_handle_error; callback takes place with <c>Reason = failover</c>.
+If a peer is selected then a &app_prepare_retransmit;
callback takes place, after which the semantics are the same as
-following an initial
-<seealso marker="diameter_app#prepare_request">
-prepare_request/3</seealso>
-callback.</p>
+following an initial &app_prepare_request; callback.</p>
</item>
<item>
<p>
If an encode error takes place during
retransmission then the request process fails and
-<c>{error, failure}</c> is returned.</p>
+<c>{error,failure}</c> is returned.</p>
</item>
<item>
@@ -910,7 +1212,7 @@ retransmission then the request process fails and
If an application callback made in processing the request fails
(pick_peer, prepare_request, prepare_retransmit,
handle_answer or handle_error) then either
-<c>{error, encode}</c> or <c>{error, failure}</c>
+<c>{error,encode}</c> or <c>{error,failure}</c>
is returned depending on whether or not there has been an
attempt to send the request over the transport.</p>
</item>
@@ -918,18 +1220,17 @@ attempt to send the request over the transport.</p>
</list>
<p>
-Note that <c>{error, encode}</c> is the only return value which
+Note that <c>{error,encode}</c> is the only return value which
guarantees that the request has <em>not</em> been sent over the
-transport.</p>
+transport connection.</p>
-<marker id="origin_state_id"/>
</desc>
</func>
<!-- ===================================================================== -->
<func>
-<name>origin_state_id() -> Unsigned32()</name>
+<name>origin_state_id() -> &dict_Unsigned32;</name>
<fsummary>Returns a reasonable Origin-State-Id.</fsummary>
<desc>
<p>
@@ -938,26 +1239,26 @@ outgoing messages.</p>
<p>
The value returned is the number of seconds since 19680120T031408Z,
-the first value that can be encoded as a Diameter Time(),
+the first value that can be encoded as a Diameter <c>&dict_Time;</c>,
at the time the diameter application was started.</p>
-<marker id="remove_transport"/>
</desc>
</func>
<!-- ===================================================================== -->
<func>
-<name>remove_transport(SvcName, Pred) -> ok</name>
+<name>remove_transport(SvcName, Pred) -> ok | {error, Reason}</name>
<fsummary>Remove previously added transports.</fsummary>
<type>
-<v>SvcName = service_name()</v>
-<v>Pred = Fun | MFA | ref() | list() | true | false</v>
+<v>SvcName = &service_name;</v>
+<v>Pred = Fun | MFA | &transport_ref; | list() | true | false</v>
<v></v>
-<v>Fun = fun((reference(), connect|listen, list()) -> boolean())</v>
-<v>&nbsp;&nbsp;&nbsp; | fun((reference(), list()) -> boolean())</v>
+<v>Fun = fun((&transport_ref;, connect|listen, list()) -> boolean())</v>
+<v>&nbsp;&nbsp;&nbsp; | fun((&transport_ref;, list()) -> boolean())</v>
<v>&nbsp;&nbsp;&nbsp; | fun((list()) -> boolean())</v>
<v>MFA = {atom(), atom(), list()}</v>
+<v>Reason = term()</v>
</type>
<desc>
<p>
@@ -967,50 +1268,329 @@ Remove previously added transports.</p>
<c>Pred</c> determines which transports to remove.
An arity-3-valued <c>Pred</c> removes all transports for which
<c>Pred(Ref, Type, Opts)</c> returns <c>true</c>, where <c>Type</c> and
-<c>Opts</c> are as passed to <seealso
-marker="#add_transport">add_transport/2</seealso> and <c>Ref</c> is
-as returned by the corresponding call.
+<c>Opts</c> are as passed to &add_transport; and <c>Ref</c> is
+as returned by it.
The remaining forms are equivalent to an arity-3 fun as follows.</p>
-<code>
-Pred = fun(reference(), list()): fun(Ref, _, Opts) -> Pred(Ref, Opts) end
-Pred = fun(list()): fun(_, _, Opts) -> Pred(Opts) end
-Pred = reference(): fun(Ref, _, _) -> Pred == Ref end
-Pred = list(): fun(_, _, Opts) -> [] == Pred -- Opts end
-Pred = true: fun(_, _, _) -> true end
-Pred = false: fun(_, _, _) -> false end
+<pre>
+Pred = fun(transport_ref(), list()): fun(Ref, _, Opts) -> Pred(Ref, Opts) end
+Pred = fun(list()): fun(_, _, Opts) -> Pred(Opts) end
+Pred = transport_ref(): fun(Ref, _, _) -> Pred == Ref end
+Pred = list(): fun(_, _, Opts) -> [] == Pred -- Opts end
+Pred = true: fun(_, _, _) -> true end
+Pred = false: fun(_, _, _) -> false end
Pred = {M,F,A}: fun(Ref, Type, Opts) -> apply(M, F, [Ref, Type, Opts | A]) end
-</code>
+</pre>
<p>
-Removing a transport causes all associated transport connections to
-be broken.
-A base application DPR message with
-Disconnect-Cause <c>DO_NOT_WANT_TO_TALK_TO_YOU</c> will be sent
-to each connected peer before disassociating the transport configuration
-from the service and terminating the transport upon reception of
-DPA or timeout.</p>
-
-<!-- TODO: document the timeout value, possibly make configurable. -->
+Removing a transport causes the corresponding transport processes to
+be terminated.
+Whether or not a DPR message is sent to a peer is
+controlled by value of &disconnect_cb;
+configured on the transport.</p>
-<marker id="service_info"/>
</desc>
</func>
<!-- ===================================================================== -->
<func>
-<name>service_info(SvcName, Item) -> Value</name>
-<fsummary>Return specific information about a started service.</fsummary>
+<name>service_info(SvcName, Info) -> term()</name>
+<fsummary>Return information about a started service.</fsummary>
<type>
-<v>SvcName = service_name()</v>
-<v>Value = term()</v>
+<v>SvcName = &service_name;</v>
+<v>Info = Item | [Info]</v>
+<v>Item = atom()</v>
</type>
<desc>
<p>
-Return information about a started service.</p>
+Return information about a started service.
+Requesting info for an unknown service causes <c>undefined</c> to be
+returned.
+Requesting a list of items causes a tagged list to be
+returned.</p>
+
+<p>
+<c>Item</c> can be one of the following.</p>
+
+<taglist>
+
+<tag><c>'Origin-Host'</c></tag>
+<tag><c>'Origin-Realm'</c></tag>
+<tag><c>'Vendor-Id'</c></tag>
+<tag><c>'Product-Name'</c></tag>
+<tag><c>'Origin-State-Id'</c></tag>
+<tag><c>'Host-IP-Address'</c></tag>
+<tag><c>'Supported-Vendor'</c></tag>
+<tag><c>'Auth-Application-Id'</c></tag>
+<tag><c>'Inband-Security-Id'</c></tag>
+<tag><c>'Acct-Application-Id'</c></tag>
+<tag><c>'Vendor-Specific-Application-Id'</c></tag>
+<tag><c>'Firmware-Revision'</c></tag>
+<item>
+<p>
+Return a capability value as configured with &start_service;.</p>
+</item>
+
+<tag><c>applications</c></tag>
+<item>
+<p>
+Return the list of applications as configured with &start_service;.
+</p>
+</item>
+
+<tag><c>capabilities</c></tag>
+<item>
+<p>
+Return a tagged list of all capabilities values as configured with
+&start_service;.</p>
+</item>
+
+<tag><c>transport</c></tag>
+<item>
+<p>
+Return a list containing one entry for each of the service's transport
+as configured with &add_transport;.
+Each entry is a tagged list containing both configuration and
+information about established peer connections.
+An example return value with for a client service with Origin-Host
+"client.example.com" configured with a single transport connected to
+"server.example.com" might look as follows.</p>
+
+<pre>
+[[{ref,#Ref&lt;0.0.0.93>},
+ {type,connect},
+ {options,[{transport_module,diameter_tcp},
+ {transport_config,[{ip,{127,0,0,1}},
+ {raddr,{127,0,0,1}},
+ {rport,3868},
+ {reuseaddr,true}]}]},
+ {watchdog,{&lt;0.66.0>,{1346,171491,996448},okay}},
+ {peer,{&lt;0.67.0>,{1346,171491,999906}}},
+ {apps,[{0,common}]},
+ {caps,[{origin_host,{"client.example.com","server.example.com"}},
+ {origin_realm,{"example.com","example.com"}},
+ {host_ip_address,{[{127,0,0,1}],[{127,0,0,1}]}},
+ {vendor_id,{0,193}},
+ {product_name,{"Client","Server"}},
+ {origin_state_id,{[],[]}},
+ {supported_vendor_id,{[],[]}},
+ {auth_application_id,{[0],[0]}},
+ {inband_security_id,{[],[0]}},
+ {acct_application_id,{[],[]}},
+ {vendor_specific_application_id,{[],[]}},
+ {firmware_revision,{[],[]}},
+ {avp,{[],[]}}]},
+ {port,[{owner,&lt;0.69.0>},
+ {module,diameter_tcp},
+ {socket,{{127,0,0,1},48758}},
+ {peer,{{127,0,0,1},3868}},
+ {statistics,[{recv_oct,656},
+ {recv_cnt,6},
+ {recv_max,148},
+ {recv_avg,109},
+ {recv_dvi,19},
+ {send_oct,836},
+ {send_cnt,6},
+ {send_max,184},
+ {send_avg,139},
+ {send_pend,0}]}]},
+ {statistics,[{{{0,258,0},recv},3},
+ {{{0,258,1},send},3},
+ {{{0,257,0},recv},1},
+ {{{0,257,1},send},1},
+ {{{0,258,0},recv,{'Result-Code',2001}},3},
+ {{{0,280,1},recv},2},
+ {{{0,280,0},send},2}]}]]
+</pre>
+
+<p>
+Here <c>ref</c> is a <c>&transport_ref;</c> and <c>options</c>
+the corresponding <c>&transport_opt;</c> list passed to
+&add_transport;.
+The <c>watchdog</c> entry shows the state of a connection's RFC 3539 watchdog
+state machine.
+The <c>peer</c> entry identifies the <c>&app_peer_ref;</c> for
+which there will have been &app_peer_up; callbacks for the
+Diameter applications identified by the <c>apps</c> entry,
+<c>common</c> being the <c>&application_alias;</c>.
+The <c>caps</c> entry identifies the capabilities sent by the local
+node and received from the peer during capabilities exchange.
+The <c>port</c> entry displays socket-level information about the
+transport connection.
+The <c>statistics</c> entry presents Diameter-level counters,
+an entry like <c>{{{0,280,1},recv},2}</c> saying that the client has
+received 2 DWR messages: <c>{0,280,1} = {Application_Id, Command_Code,
+R_Flag}</c>.</p>
+
+<p>
+Note that <c>watchdog</c>, <c>peer</c>, <c>apps</c>, <c>caps</c>
+and <c>port</c> entries depend on connectivity
+with the peer and may not be present.
+Note also that the <c>statistics</c> entry presents values acuumulated
+during the lifetime of the transport configuration.</p>
+
+<p>
+A listening transport presents its information slightly differently
+since there may be multiple accepted connections for the same
+<c>&transport_ref;</c>.
+The <c>transport</c> info returned by a server with a single client
+connection might look as follows.</p>
+
+<pre>
+[[{ref,#Ref&lt;0.0.0.61>},
+ {type,listen},
+ {options,[{transport_module,diameter_tcp},
+ {transport_config,[{reuseaddr,true},
+ {ip,{127,0,0,1}},
+ {port,3868}]}]},
+ {accept,[[{watchdog,{&lt;0.56.0>,{1346,171481,226895},okay}},
+ {peer,{&lt;0.58.0>,{1346,171491,999511}}},
+ {apps,[{0,common}]},
+ {caps,[{origin_host,{"server.example.com","client.example.com"}},
+ {origin_realm,{"example.com","example.com"}},
+ {host_ip_address,{[{127,0,0,1}],[{127,0,0,1}]}},
+ {vendor_id,{193,0}},
+ {product_name,{"Server","Client"}},
+ {origin_state_id,{[],[]}},
+ {supported_vendor_id,{[],[]}},
+ {auth_application_id,{[0],[0]}},
+ {inband_security_id,{[],[]}},
+ {acct_application_id,{[],[]}},
+ {vendor_specific_application_id,{[],[]}},
+ {firmware_revision,{[],[]}},
+ {avp,{[],[]}}]},
+ {port,[{owner,&lt;0.62.0>},
+ {module,diameter_tcp},
+ {socket,{{127,0,0,1},3868}},
+ {peer,{{127,0,0,1},48758}},
+ {statistics,[{recv_oct,1576},
+ {recv_cnt,16},
+ {recv_max,184},
+ {recv_avg,98},
+ {recv_dvi,26},
+ {send_oct,1396},
+ {send_cnt,16},
+ {send_max,148},
+ {send_avg,87},
+ {send_pend,0}]}]}],
+ [{watchdog,{&lt;0.72.0>,{1346,171491,998404},initial}}]]},
+ {statistics,[{{{0,280,0},recv},7},
+ {{{0,280,1},send},7},
+ {{{0,258,0},send,{'Result-Code',2001}},3},
+ {{{0,258,1},recv},3},
+ {{{0,258,0},send},3},
+ {{{0,280,1},recv},5},
+ {{{0,280,0},send},5},
+ {{{0,257,1},recv},1},
+ {{{0,257,0},send},1}]}]]
+</pre>
+
+<p>
+The information presented here is as in the <c>connect</c> case except
+that the client connections are grouped under an <c>accept</c> tuple.</p>
+
+</item>
+
+<tag><c>connections</c></tag>
+<item>
+<p>
+Return a list containing one entry for every established transport
+connection whose watchdog state machine is not in the <c>down</c>
+state.
+This is a flat view of <c>transport</c> info which lists only active
+connections and for which Diameter-level statistics are accumulated
+only for the lifetime of the transport connection.
+A return value for the server above might look as follows.</p>
+
+<pre>
+[[{ref,#Ref&lt;0.0.0.61>},
+ {type,accept},
+ {options,[{transport_module,diameter_tcp},
+ {transport_config,[{reuseaddr,true},
+ {ip,{127,0,0,1}},
+ {port,3868}]}]},
+ {watchdog,{&lt;0.56.0>,{1346,171481,226895},okay}},
+ {peer,{&lt;0.58.0>,{1346,171491,999511}}},
+ {apps,[{0,common}]},
+ {caps,[{origin_host,{"server.example.com","client.example.com"}},
+ {origin_realm,{"example.com","example.com"}},
+ {host_ip_address,{[{127,0,0,1}],[{127,0,0,1}]}},
+ {vendor_id,{193,0}},
+ {product_name,{"Server","Client"}},
+ {origin_state_id,{[],[]}},
+ {supported_vendor_id,{[],[]}},
+ {auth_application_id,{[0],[0]}},
+ {inband_security_id,{[],[]}},
+ {acct_application_id,{[],[]}},
+ {vendor_specific_application_id,{[],[]}},
+ {firmware_revision,{[],[]}},
+ {avp,{[],[]}}]},
+ {port,[{owner,&lt;0.62.0>},
+ {module,diameter_tcp},
+ {socket,{{127,0,0,1},3868}},
+ {peer,{{127,0,0,1},48758}},
+ {statistics,[{recv_oct,10124},
+ {recv_cnt,132},
+ {recv_max,184},
+ {recv_avg,76},
+ {recv_dvi,9},
+ {send_oct,10016},
+ {send_cnt,132},
+ {send_max,148},
+ {send_avg,75},
+ {send_pend,0}]}]},
+ {statistics,[{{{0,280,0},recv},62},
+ {{{0,280,1},send},62},
+ {{{0,258,0},send,{'Result-Code',2001}},3},
+ {{{0,258,1},recv},3},
+ {{{0,258,0},send},3},
+ {{{0,280,1},recv},66},
+ {{{0,280,0},send},66},
+ {{{0,257,1},recv},1},
+ {{{0,257,0},send},1}]}]]
+</pre>
+
+<p>
+Note that there may be multiple entries with the same <c>ref</c>, in
+contrast to <c>transport</c> info.</p>
+</item>
+
+<tag><c>statistics</c></tag>
+<item>
+<p>
+Return a <c>{{Counter, Ref}, non_neg_integer()}</c> list of counter values.
+<c>Ref</c> can be either a <c>&transport_ref;</c>
+or a <c>&app_peer_ref;</c>.
+Entries for the latter are folded into corresponding entries for the
+former as peer connections go down.
+Entries for both are removed at &remove_transport;.
+The Diameter-level statistics returned by <c>transport</c> and
+<c>connections</c> info are based upon these entries.</p>
+</item>
+
+<tag><c>&app_peer_ref;</c></tag>
+<item>
+<p>
+Return transport configuration associated with a single peer, as
+passed to &add_transport;.
+The returned list is empty if the peer is unknown.
+Otherwise it contains the <c>ref</c>, <c>type</c> and <c>options</c>
+tuples as in <c>transport</c> and <c>connections</c> info above.
+For example:</p>
+
+<pre>
+[{ref,#Ref&lt;0.0.0.61>},
+ {type,accept},
+ {options,[{transport_module,diameter_tcp},
+ {transport_config,[{reuseaddr,true},
+ {ip,{127,0,0,1}},
+ {port,3868}]}]}]
+</pre>
+</item>
+
+</taglist>
-<marker id="services"/>
</desc>
</func>
@@ -1020,34 +1600,32 @@ Return information about a started service.</p>
<name>services() -> [SvcName]</name>
<fsummary>Return the list of started services.</fsummary>
<type>
-<v>SvcName = service_name()</v>
+<v>SvcName = &service_name;</v>
</type>
<desc>
<p>
Return the list of started services.</p>
-<marker id="session_id"/>
</desc>
</func>
<!-- ===================================================================== -->
<func>
-<name>session_id(Ident) -> OctetString()</name>
+<name>session_id(Ident) -> &dict_OctetString;</name>
<fsummary>Return a value for a Session-Id AVP.</fsummary>
<type>
-<v>Ident = DiameterIdentity()</v>
+<v>Ident = &dict_DiameterIdentity;</v>
</type>
<desc>
<p>
Return a value for a Session-Id AVP.</p>
<p>
-The value has the form required by section 8.8 of RFC 3588.
+The value has the form required by section 8.8 of &the_rfc;.
Ident should be the Origin-Host of the peer from which
the message containing the returned value will be sent.</p>
-<marker id="start"/>
</desc>
</func>
@@ -1061,10 +1639,9 @@ Start the diameter application.</p>
<p>
The diameter application must be started before starting a service.
-In a production system this will typically be accomplished by a boot
+In a production system this is typically accomplished by a boot
file, not by calling <c>start/0</c> explicitly.</p>
-<marker id="start_service"/>
</desc>
</func>
@@ -1073,8 +1650,8 @@ file, not by calling <c>start/0</c> explicitly.</p>
<name>start_service(SvcName, Options) -> ok | {error, Reason}</name>
<fsummary>Start a Diameter service.</fsummary>
<type>
-<v>SvcName = service_name()</v>
-<v>Options = [service_opt()]</v>
+<v>SvcName = &service_name;</v>
+<v>Options = [&service_opt;]</v>
<v>Reason = term()</v>
</type>
<desc>
@@ -1082,13 +1659,19 @@ file, not by calling <c>start/0</c> explicitly.</p>
Start a diameter service.</p>
<p>
-A service defines a locally-implemented Diameter peer, specifying the
-capabilities of the peer to be used during capabilities exchange and
-the Diameter applications that it supports.
-Transports are added to a service using <seealso
-marker="#add_transport">add_transport/2</seealso>.</p>
+A service defines a locally-implemented Diameter node, specifying the
+capabilities to be advertised during capabilities exchange.
+Transports are added to a service using &add_transport;.
+</p>
+
+<note>
+<p>
+A transport can both override its service's
+capabilities and restrict its supported Diameter applications so
+"service = Diameter node as identified by Origin-Host" is not
+necessarily the case.</p>
+</note>
-<marker id="stop_service"/>
</desc>
</func>
@@ -1103,7 +1686,6 @@ Stop the diameter application.</p>
<p>
</p>
-<marker id="stop_service"/>
</desc>
</func>
@@ -1112,14 +1694,25 @@ Stop the diameter application.</p>
<name>stop_service(SvcName) -> ok | {error, Reason}</name>
<fsummary>Stop a Diameter service.</fsummary>
<type>
-<v>SvcName = service_name()</v>
+<v>SvcName = &service_name;</v>
<v>Reason = term()</v>
</type>
<desc>
<p>
Stop a diameter service.</p>
-<marker id="subscribe"/>
+<p>
+Stopping a service causes all associated transport connections to be
+broken.
+A DPR message with be sent as in the case of &remove_transport;.</p>
+
+<note>
+<p>
+Stopping a service does not remove any associated transports:
+&remove_transport; must
+be called to remove transport configuration.</p>
+</note>
+
</desc>
</func>
@@ -1129,17 +1722,19 @@ Stop a diameter service.</p>
<name>subscribe(SvcName) -> true</name>
<fsummary>Subscribe to event messages.</fsummary>
<type>
-<v>SvcName = service_name()</v>
+<v>SvcName = &service_name;</v>
</type>
<desc>
<p>
-Subscribe to <c>service_event()</c> messages from a service.</p>
+Subscribe to <c>&service_event;</c> messages from
+a service.</p>
<p>
It is not an error to subscribe to events from a service
-that does not yet exist.</p>
+that does not yet exist.
+Doing so before adding transports is required to guarantee the
+reception of all related events.</p>
-<marker id="unsubscribe"/>
</desc>
</func>
@@ -1149,7 +1744,7 @@ that does not yet exist.</p>
<name>unsubscribe(SvcName) -> true</name>
<fsummary>Unsubscribe to event messages.</fsummary>
<type>
-<v>SvcName = service_name()</v>
+<v>SvcName = &service_name;</v>
</type>
<desc>
<p>
@@ -1166,9 +1761,7 @@ Unsubscribe to event messages from a service.</p>
<title>SEE ALSO</title>
<p>
-<seealso marker="diameter_app">diameter_app(3)</seealso>,
-<seealso marker="diameter_transport">diameter_transport(3)</seealso>,
-<seealso marker="diameter_dict">diameter_dict(4)</seealso></p>
+&man_app;, &man_transport;, &man_dict;</p>
</section>