stdlib: Add API and doc of uri_string module

1 files changed, 325 insertions, 0 deletions

diff --git a/lib/stdlib/src/uri_string.erl b/lib/stdlib/src/uri_string.erl
new file mode 100644
index 0000000000..2c10c34f39
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+++ b/lib/stdlib/src/uri_string.erl
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+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2017. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%
+%% %CopyrightEnd%
+%%
+%%
+%% [RFC 3986, Chapter 2.2. Reserved Characters]
+%%
+%%   reserved    = gen-delims / sub-delims
+%%
+%%   gen-delims  = ":" / "/" / "?" / "#" / "[" / "]" / "@"
+%%
+%%   sub-delims  = "!" / "$" / "&" / "'" / "(" / ")"
+%%               / "*" / "+" / "," / ";" / "="
+%%
+%%
+%% [RFC 3986, Chapter 2.3. Unreserved Characters]
+%%
+%%   unreserved  = ALPHA / DIGIT / "-" / "." / "_" / "~"
+%%
+%%
+%% [RFC 3986, Chapter 3. Syntax Components]
+%%
+%% The generic URI syntax consists of a hierarchical sequence of
+%% components referred to as the scheme, authority, path, query, and
+%% fragment.
+%%
+%%    URI         = scheme ":" hier-part [ "?" query ] [ "#" fragment ]
+%%
+%%    hier-part   = "//" authority path-abempty
+%%                   / path-absolute
+%%                   / path-rootless
+%%                   / path-empty
+%%
+%%    The scheme and path components are required, though the path may be
+%%    empty (no characters).  When authority is present, the path must
+%%    either be empty or begin with a slash ("/") character.  When
+%%    authority is not present, the path cannot begin with two slash
+%%    characters ("//").  These restrictions result in five different ABNF
+%%    rules for a path (Section 3.3), only one of which will match any
+%%    given URI reference.
+%%
+%%    The following are two example URIs and their component parts:
+%%
+%%          foo://example.com:8042/over/there?name=ferret#nose
+%%          \_/   \______________/\_________/ \_________/ \__/
+%%           |           |            |            |        |
+%%        scheme     authority       path        query   fragment
+%%           |   _____________________|__
+%%          / \ /                        \
+%%          urn:example:animal:ferret:nose
+%%
+%%
+%% [RFC 3986, Chapter 3.1. Scheme]
+%%
+%% Each URI begins with a scheme name that refers to a specification for
+%% assigning identifiers within that scheme.
+%%
+%%    scheme      = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
+%%
+%%
+%% [RFC 3986, Chapter 3.2. Authority]
+%%
+%% Many URI schemes include a hierarchical element for a naming
+%% authority so that governance of the name space defined by the
+%% remainder of the URI is delegated to that authority (which may, in
+%% turn, delegate it further).
+%%
+%%    authority   = [ userinfo "@" ] host [ ":" port ]
+%%
+%%
+%% [RFC 3986, Chapter 3.2.1. User Information]
+%%
+%% The userinfo subcomponent may consist of a user name and, optionally,
+%% scheme-specific information about how to gain authorization to access
+%% the resource. The user information, if present, is followed by a
+%% commercial at-sign ("@") that delimits it from the host.
+%%
+%%    userinfo    = *( unreserved / pct-encoded / sub-delims / ":" )
+%%
+%%
+%% [RFC 3986, Chapter 3.2.2. Host]
+%%
+%% The host subcomponent of authority is identified by an IP literal
+%% encapsulated within square brackets, an IPv4 address in dotted-
+%% decimal form, or a registered name.
+%%
+%%    host        = IP-literal / IPv4address / reg-name
+%%
+%%    IP-literal = "[" ( IPv6address / IPvFuture  ) "]"
+%%
+%%    IPvFuture  = "v" 1*HEXDIG "." 1*( unreserved / sub-delims / ":" )
+%%
+%%    IPv6address =                            6( h16 ":" ) ls32
+%%                /                       "::" 5( h16 ":" ) ls32
+%%                / [               h16 ] "::" 4( h16 ":" ) ls32
+%%                / [ *1( h16 ":" ) h16 ] "::" 3( h16 ":" ) ls32
+%%                / [ *2( h16 ":" ) h16 ] "::" 2( h16 ":" ) ls32
+%%                / [ *3( h16 ":" ) h16 ] "::"    h16 ":"   ls32
+%%                / [ *4( h16 ":" ) h16 ] "::"              ls32
+%%                / [ *5( h16 ":" ) h16 ] "::"              h16
+%%                / [ *6( h16 ":" ) h16 ] "::"
+%%
+%%    ls32        = ( h16 ":" h16 ) / IPv4address
+%%                ; least-significant 32 bits of address
+%%
+%%    h16         = 1*4HEXDIG
+%%                ; 16 bits of address represented in hexadecimal
+%%
+%%    IPv4address = dec-octet "." dec-octet "." dec-octet "." dec-octet
+%%
+%%    dec-octet   = DIGIT                 ; 0-9
+%%                / %x31-39 DIGIT         ; 10-99
+%%                / "1" 2DIGIT            ; 100-199
+%%                / "2" %x30-34 DIGIT     ; 200-249
+%%                / "25" %x30-35          ; 250-255
+%%
+%%    reg-name    = *( unreserved / pct-encoded / sub-delims )
+%%
+%%
+%% [RFC 3986, Chapter 3.2.2. Port]
+%%
+%% The port subcomponent of authority is designated by an optional port
+%% number in decimal following the host and delimited from it by a
+%% single colon (":") character.
+%%
+%%    port        = *DIGIT
+%%
+%%
+%% [RFC 3986, Chapter 3.3. Path]
+%%
+%% The path component contains data, usually organized in hierarchical
+%% form, that, along with data in the non-hierarchical query component
+%% (Section 3.4), serves to identify a resource within the scope of the
+%% URI's scheme and naming authority (if any).  The path is terminated
+%% by the first question mark ("?") or number sign ("#") character, or
+%% by the end of the URI.
+%%
+%%    path          = path-abempty    ; begins with "/" or is empty
+%%                  / path-absolute   ; begins with "/" but not "//"
+%%                  / path-noscheme   ; begins with a non-colon segment
+%%                  / path-rootless   ; begins with a segment
+%%                  / path-empty      ; zero characters
+%%
+%%    path-abempty  = *( "/" segment )
+%%    path-absolute = "/" [ segment-nz *( "/" segment ) ]
+%%    path-noscheme = segment-nz-nc *( "/" segment )
+%%    path-rootless = segment-nz *( "/" segment )
+%%    path-empty    = 0<pchar>
+%%    segment       = *pchar
+%%    segment-nz    = 1*pchar
+%%    segment-nz-nc = 1*( unreserved / pct-encoded / sub-delims / "@" )
+%%                  ; non-zero-length segment without any colon ":"
+%%
+%%    pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
+%%
+%%
+%% [RFC 3986, Chapter 3.4. Query]
+%%
+%% The query component contains non-hierarchical data that, along with
+%% data in the path component (Section 3.3), serves to identify a
+%% resource within the scope of the URI's scheme and naming authority
+%% (if any).  The query component is indicated by the first question
+%% mark ("?") character and terminated by a number sign ("#") character
+%% or by the end of the URI.
+%%
+%%    query       = *( pchar / "/" / "?" )
+%%
+%%
+%% [RFC 3986, Chapter 3.5. Fragment]
+%%
+%% The fragment identifier component of a URI allows indirect
+%% identification of a secondary resource by reference to a primary
+%% resource and additional identifying information.
+%%
+%%    fragment    = *( pchar / "/" / "?" )
+%%
+%%
+%% [RFC 3986, Chapter 4.1. URI Reference]
+%%
+%% URI-reference is used to denote the most common usage of a resource
+%% identifier.
+%%
+%%    URI-reference = URI / relative-ref
+%%
+%%
+%% [RFC 3986, Chapter 4.2. Relative Reference]
+%%
+%% A relative reference takes advantage of the hierarchical syntax
+%% (Section 1.2.3) to express a URI reference relative to the name space
+%% of another hierarchical URI.
+%%
+%%    relative-ref  = relative-part [ "?" query ] [ "#" fragment ]
+%%
+%%    relative-part = "//" authority path-abempty
+%%                  / path-absolute
+%%                  / path-noscheme
+%%                  / path-empty
+%%
+%%
+%% [RFC 3986, Chapter 4.3. Absolute URI]
+%%
+%% Some protocol elements allow only the absolute form of a URI without
+%% a fragment identifier.  For example, defining a base URI for later
+%% use by relative references calls for an absolute-URI syntax rule that
+%% does not allow a fragment.
+%%
+%%    absolute-URI  = scheme ":" hier-part [ "?" query ]
+%%
+
+-module(uri_string).
+
+
+-export([compose_query/1, create_uri_reference/2, dissect_query/1, normalize/1,
+         parse/1, recompose/1, resolve_uri_reference/2, transcode/2]).
+-export_type([uri_map/0, uri_string/0, bytelist/0]).
+
+
+%%%=========================================================================
+%%%  API
+%%%=========================================================================
+
+
+-type bytelist() :: maybe_improper_list(
+                0..255 |
+                binary() | bytelist(),
+                binary() | []).
+
+%% URI compliant with RFC 3986
+%% ASCII %x21 - %x7A ("!" - "z") except
+%%   %x34    "    double quote
+%%   %x60    <    less than
+%%   %x62    >    greater than
+%%   %x92    \    backslash
+%%   %x94    ^    caret / circumflex
+%%   %x96    `    grave / accent
+-type uri_string() :: bytelist() | binary().
+
+
+%% RFC 3986, Chapter 3. Syntax Components
+-type uri_map() ::
+  #{fragment := unicode:chardata(),
+    host := unicode:chardata(),
+    path := unicode:chardata(),
+    port := non_neg_integer(),
+    query := unicode:chardata(),
+    scheme := atom(),
+    userinfo := unicode:chardata()}.
+
+%% Parse URIs
+-spec parse(URIString) -> URIMap when
+      URIString :: uri_string(),
+      URIMap :: uri_map().
+parse(_) ->
+    ok.
+
+%% Recompose URIs
+-spec recompose(URIMap) -> URIString when
+      URIMap :: uri_map(),
+      URIString :: uri_string().
+recompose(_) ->
+    ok.
+
+%% Resolve references
+-spec resolve_uri_reference(RelativeURI, AbsoluteBaseURI) -> AbsoluteDestURI when
+      RelativeURI :: uri_string(),
+      AbsoluteBaseURI :: uri_string(),
+      AbsoluteDestURI :: uri_string().
+resolve_uri_reference(_,_) ->
+    ok.
+
+%% Create references
+-spec create_uri_reference(AbsoluteSourceURI, AbsoluteBaseURI) -> RelativeDestURI when
+      AbsoluteSourceURI :: uri_string(),
+      AbsoluteBaseURI :: uri_string(),
+      RelativeDestURI :: uri_string().
+create_uri_reference(_,_) ->
+    ok.
+
+%% Normalize URIs
+-spec normalize(URIString) -> NormalizedURI when
+      URIString :: uri_string(),
+      NormalizedURI :: uri_string().
+normalize(_) ->
+    ok.
+
+%% Transcode URIs
+-spec transcode(URIString, Options) -> URIString when
+      URIString :: uri_string(),
+      Options :: [{in_encoding, unicode:encoding()}|{out_encoding, unicode:encoding()}].
+transcode(_, _) ->
+    ok.
+
+
+%% Working with query strings
+%% HTML 2.0 - application/x-www-form-urlencoded
+%% RFC 1866 [8.2.1]
+
+%% Compose urlencoded query string from a list of unescaped key/value pairs.
+-spec compose_query(QueryList) -> QueryString when
+      QueryList :: [{unicode:chardata(), unicode:chardata()}],
+      QueryString :: uri_string().
+compose_query(_) ->
+    ok.
+
+%% Dissect a query string into a list of unescaped key/value pairs.
+-spec dissect_query(QueryString) -> QueryList when
+      QueryString :: uri_string(),
+      QueryList :: [{unicode:chardata(), unicode:chardata()}].
+dissect_query(_) ->
+     ok.