Add release_handler:which_releases/1

This is an extension to which_releases that allows a user to specify the
status of the releases they wish to be returned. For instance it allows
for quickly determining which release is 'permanent' without the need of
parsing the entire release list.

3 files changed, 61 insertions, 2 deletions

diff --git a/lib/sasl/doc/src/release_handler.xml b/lib/sasl/doc/src/release_handler.xml
index 5ac0dc1acc..cf05b1a67d 100644
--- a/lib/sasl/doc/src/release_handler.xml
+++ b/lib/sasl/doc/src/release_handler.xml
@@ -431,6 +431,18 @@ release_handler:set_unpacked(RelFile, [{myapp,"1.0","/home/user"},...]).
         <p>Returns all releases known to the release handler.</p>
       </desc>
     </func>
+    <func>
+      <name>which_releases(Status) -> [{Name, Vsn, Apps, Status}]</name>
+      <fsummary>Return all known releases of a specific status</fsummary>
+      <type>
+        <v>Name = Vsn = string()</v>
+        <v>Apps = ["App-Vsn"]</v>
+        <v>Status = unpacked | current | permanent | old</v>
+      </type>
+      <desc>
+        <p>Returns all releases known to the release handler of a specific status.</p>
+      </desc>
+    </func>
   </funcs>
 
   <section>
diff --git a/lib/sasl/src/release_handler.erl b/lib/sasl/src/release_handler.erl
index bc08f94dff..5650f1433d 100644
--- a/lib/sasl/src/release_handler.erl
+++ b/lib/sasl/src/release_handler.erl
@@ -27,7 +27,8 @@
 	 unpack_release/1,
 	 check_install_release/1, check_install_release/2,
 	 install_release/1, install_release/2, remove_release/1,
-	 which_releases/0, make_permanent/1, reboot_old_release/1,
+	 which_releases/0, which_releases/1, make_permanent/1,
+	 reboot_old_release/1,
 	 set_unpacked/2, set_removed/1, install_file/2]).
 -export([upgrade_app/2, downgrade_app/2, downgrade_app/3,
 	 upgrade_script/2, downgrade_script/3,
@@ -305,6 +306,14 @@ which_releases() ->
     call(which_releases).
 
 %%-----------------------------------------------------------------
+%% Returns: [{Name, Vsn, [LibName], Status}]
+%%          Status = unpacked | current | permanent | old
+%%-----------------------------------------------------------------
+which_releases(Status) ->
+    Releases = which_releases(),
+    get_releases_with_status(Releases, Status, []).
+
+%%-----------------------------------------------------------------
 %% check_script(Script, LibDirs) -> ok | {error, Reason}
 %%-----------------------------------------------------------------
 check_script(Script, LibDirs) ->
@@ -2010,3 +2019,14 @@ get_new_libs([{App,Vsn,_LibDir}|CurrentLibs], NewLibs) ->
     end;
 get_new_libs([],_) ->
     [].
+
+%%-----------------------------------------------------------------
+%% Return a list of releases witch a specific status
+%%-----------------------------------------------------------------
+get_releases_with_status([], _, Acc) ->
+    Acc;
+get_releases_with_status([ {_, _, _, ReleaseStatus } = Head | Tail],
+                         Status, Acc) when ReleaseStatus == Status ->
+    get_releases_with_status(Tail, Status, [Head | Acc]);
+get_releases_with_status([_ | Tail], Status, Acc) ->
+    get_releases_with_status(Tail, Status, Acc).
diff --git a/lib/sasl/test/release_handler_SUITE.erl b/lib/sasl/test/release_handler_SUITE.erl
index af2183bfff..286aff9bb0 100644
--- a/lib/sasl/test/release_handler_SUITE.erl
+++ b/lib/sasl/test/release_handler_SUITE.erl
@@ -58,7 +58,8 @@ cases() ->
     [otp_2740, otp_2760, otp_5761, otp_9402, otp_9417,
      otp_9395_check_old_code, otp_9395_check_and_purge,
      otp_9395_update_many_mods, otp_9395_rm_many_mods,
-     instructions, eval_appup, supervisor_which_children_timeout].
+     instructions, eval_appup, supervisor_which_children_timeout,
+     release_handler_which_releases].
 
 groups() ->
     [{release,[],
@@ -546,6 +547,32 @@ supervisor_which_children_timeout(cleanup, Conf) ->
     stop_node(node_name(supervisor_which_children_timeout)).
 
 %%-----------------------------------------------------------------
+%% release_handler:which_releases/0 and 1 test
+%%-----------------------------------------------------------------
+release_handler_which_releases(Conf) ->
+    PrivDir = priv_dir(Conf),
+    Dir = filename:join(PrivDir,"release_handler_which_releases"),
+    DataDir = ?config(data_dir,Conf),
+    LibDir = filename:join([DataDir,release_handler_timeouts]),
+
+    Rel1 = create_and_install_fake_first_release(Dir,[{dummy,"0.1",LibDir}]),
+
+    {ok, Node} = t_start_node(release_handler_which_releases, Rel1, []),
+    Releases0 = rpc:call(Node, release_handler, which_releases, []),
+    Releases1 = rpc:call(Node, release_handler, which_releases, [permanent]),
+    Releases2 = rpc:call(Node, release_handler, which_releases, [old]),
+
+    1 = length(Releases0),
+    1 = length(Releases1),
+    0 = length(Releases2),
+
+    ?t:format("release_handler:which_releases/0: ~p~n", [Releases0]),
+    ?t:format("release_handler:which_releases/1: ~p~n", [Releases1]),
+    ?t:format("release_handler:which_releases/1: ~p~n", [Releases2]),
+
+    ok.
+
+%%-----------------------------------------------------------------
 %% Ticket: OTP-2740
 %% Slogan: vsn not numeric doesn't work so good in release_handling
 %%-----------------------------------------------------------------