Add Elixir test on ejabberd hooks

This is to prepare ejabberd_hooks module refactoring.

I also expanded API to help with testing.

Makefile.in

@@ -312,6 +312,9 @@ test:
 	@echo "*************************************************************************"
 	$(REBAR) skip_deps=true ct
 
+quicktest:
+	$(REBAR) skip_deps=true ct suites=elixir
+
 .PHONY: src doc edoc dialyzer Makefile TAGS clean clean-rel distclean rel \
 	install uninstall uninstall-binary uninstall-all translations deps test spec \
-	erlang_plt deps_plt ejabberd_plt
+	quicktest erlang_plt deps_plt ejabberd_plt

src/ejabberd_hooks.erl

@@ -42,9 +42,12 @@
 	 add_dist/6,
 	 delete/5,
 	 delete_dist/6,
+	 get_handlers/2,
 	 run/3,
 	 run_fold/4]).
 
+-export([delete_all_hooks/0]).
+
 %% gen_server callbacks
 -export([init/1,
 	 handle_call/3,
@@ -67,13 +70,13 @@
 start_link() ->
     gen_server:start_link({local, ejabberd_hooks}, ejabberd_hooks, [], []).
 
--spec add(atom(), fun(), number()) -> any().
+-spec add(atom(), fun(), number()) -> ok.
 
 %% @doc See add/4.
 add(Hook, Function, Seq) when is_function(Function) ->
     add(Hook, global, undefined, Function, Seq).
 
--spec add(atom(), binary() | atom(), fun() | atom() , number()) -> any().
+-spec add(atom(), HostOrModule :: binary() | atom(), fun() | atom() , number()) -> ok.
 add(Hook, Host, Function, Seq) when is_function(Function) ->
     add(Hook, Host, undefined, Function, Seq);
 
@@ -82,17 +85,17 @@ add(Hook, Host, Function, Seq) when is_function(Function) ->
 add(Hook, Module, Function, Seq) ->
     add(Hook, global, Module, Function, Seq).
 
--spec add(atom(), binary() | global, atom(), atom() | fun(), number()) -> any().
+-spec add(atom(), binary() | global, atom(), atom() | fun(), number()) -> ok.
 
 add(Hook, Host, Module, Function, Seq) ->
     gen_server:call(ejabberd_hooks, {add, Hook, Host, Module, Function, Seq}).
 
--spec add_dist(atom(), atom(), atom(), atom() | fun(), number()) -> any().
+-spec add_dist(atom(), atom(), atom(), atom() | fun(), number()) -> ok.
 
 add_dist(Hook, Node, Module, Function, Seq) ->
     gen_server:call(ejabberd_hooks, {add, Hook, global, Node, Module, Function, Seq}).
 
--spec add_dist(atom(), binary() | global, atom(), atom(), atom() | fun(), number()) -> any().
+-spec add_dist(atom(), binary() | global, atom(), atom(), atom() | fun(), number()) -> ok.
 
 add_dist(Hook, Host, Node, Module, Function, Seq) ->
     gen_server:call(ejabberd_hooks, {add, Hook, Host, Node, Module, Function, Seq}).
@@ -128,6 +131,17 @@ delete_dist(Hook, Node, Module, Function, Seq) ->
 delete_dist(Hook, Host, Node, Module, Function, Seq) ->
     gen_server:call(ejabberd_hooks, {delete, Hook, Host, Node, Module, Function, Seq}).
 
+-spec delete_all_hooks() -> true. 
+
+%% @doc Primarily for testing / instrumentation
+delete_all_hooks() ->
+    gen_server:call(ejabberd_hooks, {delete_all}).
+
+-spec get_handlers(atom(), binary() | global) -> [{Seq :: integer(), Module :: atom(), Function :: atom()}].
+
+get_handlers(Hook, Host) ->
+    gen_server:call(ejabberd_hooks, {get_handlers, Hook, Host}).
+
 -spec run(atom(), list()) -> ok.
 
 %% @doc Run the calls of this hook in order, don't care about function results.
@@ -245,6 +259,17 @@ handle_call({delete, Hook, Host, Node, Module, Function, Seq}, _From, State) ->
 		    ok
 	    end,
     {reply, Reply, State};
+handle_call({get_handlers, Hook, Host}, _From, State) ->
+    Reply = case ets:lookup(hooks, {Hook, Host}) of
+                [{_, Handlers}] ->
+                    Handlers;
+                [] ->
+                    []
+            end,
+    {reply, Reply, State};
+handle_call({delete_all}, _From, State) ->
+    Reply = ets:delete_all_objects(hooks),
+    {reply, Reply, State};
 handle_call(_Request, _From, State) ->
     Reply = ok,
     {reply, Reply, State}.

test/ejabberd_hooks_test.exs

@@ -0,0 +1,192 @@
+# ----------------------------------------------------------------------
+#
+# ejabberd, Copyright (C) 2002-2015   ProcessOne
+#
+# This program is free software; you can redistribute it and/or
+# modify it under the terms of the GNU General Public License as
+# published by the Free Software Foundation; either version 2 of the
+# License, or (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+#
+# ----------------------------------------------------------------------
+
+defmodule EjabberdHooksTest do
+  use ExUnit.Case, async: true
+  
+  @author "mremond@process-one.net"
+  @host <<"domain.net">>
+  @self __MODULE__
+  
+  setup_all do
+    {:ok, _Pid} = :ejabberd_hooks.start_link
+    :ok
+  end
+  
+  setup do
+    :meck.unload
+    :true = :ejabberd_hooks.delete_all_hooks
+    :ok
+  end  
+  
+  test "An anonymous function can be added as a hook" do
+    hookname = :test_fun_hook
+    :ok = :ejabberd_hooks.add(hookname, @host, fn _ -> :ok end, 50)
+    [{50, :undefined, _}] = :ejabberd_hooks.get_handlers(hookname, @host)
+  end
+  
+  test "A module function can be added as a hook" do
+    hookname = :test_mod_hook
+    callback = :hook_callback
+    :ok = :ejabberd_hooks.add(hookname, @host, @self, callback, 40)
+    [{40, @self, callback}] = :ejabberd_hooks.get_handlers(hookname, @host)
+  end
+
+  test "An anonymous function can be removed from hook handlers" do
+    hookname = :test_fun_hook
+    anon_fun = fn _ -> :ok end                                              
+    :ok = :ejabberd_hooks.add(hookname, @host, anon_fun, 50)
+    :ok = :ejabberd_hooks.delete(hookname, @host, anon_fun, 50)
+    [] = :ejabberd_hooks.get_handlers(hookname, @host)
+  end
+
+  test "An module function can be removed from hook handlers" do
+    hookname = :test_mod_hook
+    callback = :hook_callback
+    :ok = :ejabberd_hooks.add(hookname, @host, @self, callback, 40)
+    :ok = :ejabberd_hooks.delete(hookname, @host, @self, callback, 40)
+    [] = :ejabberd_hooks.get_handlers(hookname, @host)
+    # TODO: Check that removed function is not call anymore
+  end
+
+  test "'Run hook' call registered handler once" do
+    test_result = :hook_result
+    run_hook([], fn -> test_result end, test_result)
+  end
+
+  test "'Run hook' can call registered handler with parameters" do
+    test_result = :hook_result_with_params
+    run_hook([:hook_params], fn _ -> test_result end, test_result)
+  end
+
+  # TODO test "Several handlers are run in order by hook"
+  
+  test "Hook run chain is stopped when handler return 'stop'" do
+    # setup test
+    hookname = :test_mod_hook
+    modulename = :hook_module
+    mock(modulename, :hook_callback1, fn _ -> :stop end)
+    mock(modulename, :hook_callback2, fn _ -> :end_result end)
+    
+    :ok = :ejabberd_hooks.add(hookname, @host, modulename, :hook_callback1, 40)
+    :ok = :ejabberd_hooks.add(hookname, @host, modulename, :hook_callback1, 50)
+
+    :ok = :ejabberd_hooks.run(hookname, @host, [:hook_params])
+    # callback2 is never run:
+    [{_pid, {modulename, callback, [:hook_params]}, :stop}] = :meck.history(modulename)   
+  end
+
+  test "Run fold hooks accumulate state in correct order through handlers" do
+    # setup test
+    hookname = :test_mod_hook
+    modulename = :hook_module
+    mock(modulename, :hook_callback1, fn(list, user) -> [user|list] end)
+    mock(modulename, :hook_callback2, fn(list, _user) -> ["jid2"|list] end)
+    
+    :ok = :ejabberd_hooks.add(hookname, @host, modulename, :hook_callback1, 40)
+    :ok = :ejabberd_hooks.add(hookname, @host, modulename, :hook_callback2, 50)
+    
+    ["jid2", "jid1"] = :ejabberd_hooks.run_fold(hookname, @host, [], ["jid1"])
+  end
+
+  test "Hook run_fold are executed based on priority order, not registration order" do
+    # setup test
+    hookname = :test_mod_hook
+    modulename = :hook_module
+    mock(modulename, :hook_callback1, fn(acc) -> :first end)
+    mock(modulename, :hook_callback2, fn(acc) -> :second end)
+
+    :ok = :ejabberd_hooks.add(hookname, @host, modulename, :hook_callback2, 50)
+    :ok = :ejabberd_hooks.add(hookname, @host, modulename, :hook_callback1, 40)
+    
+    :second = :ejabberd_hooks.run_fold(hookname, @host, :started, [])
+    # Both module have been called:
+    2 = length(:meck.history(modulename))
+  end
+  
+  # TODO: Test with ability to stop and return a value
+  test "Hook run_fold chain is stopped when handler return 'stop'" do
+    # setup test
+    hookname = :test_mod_hook
+    modulename = :hook_module
+    mock(modulename, :hook_callback1, fn(acc) -> :stop end)
+    mock(modulename, :hook_callback2, fn(acc) -> :executed end)
+
+    :ok = :ejabberd_hooks.add(hookname, @host, modulename, :hook_callback1, 40)
+    :ok = :ejabberd_hooks.add(hookname, @host, modulename, :hook_callback2, 50)
+
+    :stopped = :ejabberd_hooks.run_fold(hookname, @host, :started, [])
+    # Only one module has been called
+    [{_pid, {modulename, :hook_callback1, [started]}, :stop}] = :meck.history(modulename)
+  end
+
+  test "Error in run_fold is ignored" do
+    run_fold_crash(fn(acc) -> raise :crashed end)
+  end
+
+  test "Throw in run_fold is ignored" do
+    run_fold_crash(fn(acc) -> throw :crashed end)
+  end
+
+  test "Exit in run_fold is ignored" do
+    run_fold_crash(fn(acc) -> exit :crashed end)
+  end
+  
+  # test for run hook with various number of params
+  def run_hook(params, fun, result) do 
+    # setup test
+    hookname = :test_mod_hook
+    modulename = :hook_module
+    callback = :hook_callback
+    mock(modulename, callback, fun)
+    
+    # Then check
+    :ok = :ejabberd_hooks.add(hookname, @host, modulename, callback, 40)
+    :ok = :ejabberd_hooks.run(hookname, @host, params)
+    [{_pid, {modulename, callback, params}, result}] = :meck.history(modulename)   
+  end
+
+  def run_fold_crash(crash_fun) do
+    # setup test
+    hookname = :test_mod_hook
+    modulename = :hook_module
+    mock(modulename, :hook_callback1, crash_fun)
+    mock(modulename, :hook_callback2, fn(acc) -> :final end)
+
+    :ok = :ejabberd_hooks.add(hookname, @host, modulename, :hook_callback1, 40)
+    :ok = :ejabberd_hooks.add(hookname, @host, modulename, :hook_callback2, 50)
+
+    :final = :ejabberd_hooks.run_fold(hookname, @host, :started, [])
+    # Both handlers were called
+    2 = length(:meck.history(modulename))    
+  end
+
+  # TODO refactor: Move to ejabberd_test_mock
+  def mock(module, function, fun) do
+    try do
+      :meck.new(module, [:non_strict])
+    catch
+      :error, {:already_started, _pid} -> :ok
+    end
+
+    :meck.expect(module, function, fun)
+  end
+  
+end