Erlang Quality of Life Improvements

Download here: https://marketplace.visualstudio.com/items?itemName=bocdev.erlang-code-generation

This is an Extension for Visual Studio Code to make using erlang in vscode just better. Its currently under development. Feel free to create pull requests for anything you think would be useful!

Features

Side bar
Code Generation & Snippets

Version 1 introduces the project explorer, which gives you a top level view of your project and all the files within. Selecting a module or one of the items within one (definitions, macros, records, types, exported functions, imported function, tests) will take you to the module and the line number the sub item is found out. Pressing the pen icon on module items will copy it to your clipboard so you can use said item.

Side

Eunit testing

By pressing the testing icon to the right of a module in the side panel, it will run the eunit tests in the module and produce the output to an ouput channel called "Eunit Tests".

Docs

Comments

%%%-----------------------------------------------------------------------------
%%% @doc
%%% 
%%% @author <USER_NAME>
%%% @end
%%%-----------------------------------------------------------------------------

-module(<MODULE_NAME>).
-author("<USER_NAME>").

Section

%%%=============================================================================
%%% 
%%%=============================================================================

Function

%%-----------------------------------------------------------------------------
%% @doc
%% 
%% @end
%%-----------------------------------------------------------------------------

Modules

Supervisor

%%%-----------------------------------------------------------------------------
%%% @doc
%%% Supervisor built from template.
%%% @author <USER_NAME>
%%% @end
%%%-----------------------------------------------------------------------------

-module(<MODULE_NAME>).
-author("<USER_NAME>").
-behaviour(supervisor).

%%%=============================================================================
%%% Export and Defs
%%%=============================================================================

%% External API
-export([
	start_link/0
]).

%% Callbacks
-export([init/1]).

-define(SERVER, ?MODULE).

%%%=============================================================================
%%% API
%%%=============================================================================

-spec start_link() -> supervisor:startlink_ret().
start_link() ->
    supervisor:start_link({local, ?SERVER}, ?MODULE, []).

%%%=============================================================================
%%%  Callbacks
%%%=============================================================================

init([]) ->
    SupFlags = #{strategy => one_for_all,
                 intensity => 0,
                 period => 1},
    ChildSpecs = [],
    {ok, {SupFlags, ChildSpecs}}.

%%%=============================================================================
%%% Internal functions
%%%=============================================================================

%%%=============================================================================
%%% Eunit Tests
%%%=============================================================================

-ifdef(TEST).

-include_lib("eunit/include/eunit.hrl").

example_test() ->
    ?assertEqual(true, true).

-endif.

Empty

%%%-----------------------------------------------------------------------------
%%% @doc
%%% Empty Module built from template.
%%% @author <USER_NAME>
%%% @end
%%%-----------------------------------------------------------------------------

-module(<MODULE_NAME>).
-author("<USER_NAME>").

%%%=============================================================================
%%% Export and Defs
%%%=============================================================================

%% External API
-export([

]).

-define(SERVER, ?MODULE).

%% example record
-record(example_record, {

}).
-type example_record() :: example_record.

%%%=============================================================================
%%% API
%%%=============================================================================

%%%=============================================================================
%%% Internal functions
%%%=============================================================================

%%%=============================================================================
%%% Eunit Tests
%%%=============================================================================

-ifdef(TEST).

-include_lib("eunit/include/eunit.hrl").

example_test() ->
    ?assertEqual(true, true).

-endif.

Gen Server

%%%-----------------------------------------------------------------------------
%%% @doc
%%% Gen Server built from template.
%%% @author <USER_NAME>
%%% @end
%%%-----------------------------------------------------------------------------

-module(<MODULE_NAME>).
-author("<USER_NAME>").
-behaviour(gen_server).

%%%=============================================================================
%%% Export and Defs
%%%=============================================================================

%% External API
-export([start_link/0]).

%% Callbacks
-export([
	init/1, 
	handle_call/3, 
	handle_cast/2, 
	handle_info/2,
	terminate/2, 
	code_change/3
]).

-define(SERVER, ?MODULE).

%% Loop state
-record(loop_state, {
	
}).
-type loop_state() :: loop_state.

%%%=============================================================================
%%% API
%%%=============================================================================

-spec start_link() -> {ok, pid()} | {error, {already_started, pid()}} | {error, Reason::any()}.
start_link() ->
	gen_server:start_link({local, ?SERVER}, ?MODULE, [], []).

%%%=============================================================================
%%% Gen Server Callbacks
%%%=============================================================================

init([]) ->
	LoopState = #loop_state{}, 
	{ok, LoopState}.

handle_call(_Request, _From, LoopState) ->
	Reply = ok,
	{reply, Reply, LoopState}.

handle_cast(_Msg, LoopState) ->
	{noreply, LoopState}.

handle_info(_Info, LoopState) ->
	{noreply, LoopState}.

terminate(_Reason, _LoopState) ->
	ok.

code_change(_OldVsn, LoopState, _Extra) ->
	{ok, LoopState}.

%%%=============================================================================
%%% Internal functions
%%%=============================================================================

%%%=============================================================================
%%% Eunit Tests
%%%=============================================================================

-ifdef(TEST).

-include_lib("eunit/include/eunit.hrl").

example_test() ->
    ?assertEqual(true, true).

-endif.

Gen State Machine

%%%-----------------------------------------------------------------------------
%%% @doc
%%% Gen State Machine built from template.
%%% @author <USER_NAME>
%%% @end
%%%-----------------------------------------------------------------------------

-module(<MODULE_NAME>).
-author("<USER_NAME>").
-behaviour(gen_statem).

%%%=============================================================================
%%% Export and Defs
%%%=============================================================================

-define(SERVER, ?MODULE).

%% External API
-export([
	start_link/0,
	stop/0,
    example_action/0
]).

%% Gen State Machine Callbacks
-export([
	init/1,
	code_change/4,
	callback_mode/0,
	terminate/3
]).

%% State transitions
-export([
	example_state/3,
	next_example_state/3,
	handle_event/3
]).

%%%=============================================================================
%%% API
%%%=============================================================================

-spec start_link() -> {ok, pid()} | {error, {already_started, pid()}} | {error, Reason::any()}.
start_link() ->
	gen_statem:start({local, ?SERVER}, ?MODULE, [], []).

-spec stop() -> ok;
stop() ->
    gen_statem:stop(?SERVER).	

-spec example_action() -> term();
example_action() ->
    gen_statem:call(?SERVER, example_action).

%%%=============================================================================
%%% Gen State Machine Callbacks
%%%=============================================================================

init([]) ->
	State = example_state,
	Data = data, 
	{ok, State, Data}.

terminate(_Reason, _State, _Data) ->
    void.

code_change(_Vsn, State, Data, _Extra) ->
    {ok,State,Data}.
	
callback_mode() -> 
	state_functions.

%%%=============================================================================
%%% State transitions
%%%=============================================================================

example_state({call,From}, example_action, Data) ->
    {next_state, next_example_state, Data, [{reply,From,next_example_state}]};
example_state(EventType, EventContent, Data) ->
    handle_event(EventType, EventContent, Data).

next_example_state({call,From}, example_action, Data) ->
	{next_state, example_state, Data, [{reply,From,example_state}]};
next_example_state(EventType, EventContent, Data) ->
	handle_event(EventType, EventContent, Data).

%%-----------------------------------------------------------------------------
%% @doc
%% Handle events common to all states.
%% @end
%%-----------------------------------------------------------------------------
handle_event({call,From}, get_count, Data) ->
    %% Reply with the current count
    {keep_state,Data,[{reply,From,Data}]};
handle_event(_, _, Data) ->
    %% Ignore all other events
    {keep_state,Data}.

%%%=============================================================================
%%% Internal functions
%%%=============================================================================

%%%=============================================================================
%%% Eunit Tests
%%%=============================================================================

-ifdef(TEST).

-include_lib("eunit/include/eunit.hrl").

example_test() ->
    ?assertEqual(true, true).

-endif.

Header

%%%-----------------------------------------------------------------------------
%%% @doc
%%% Header built from template
%%% @author <USER_NAME>
%%% @end
%%%-----------------------------------------------------------------------------

-module(<MODULE_NAME>).
-author("<USER_NAME>").

%%%=============================================================================
%%% Global Definitions
%%%=============================================================================

%% example record
-record(example_record, {

}).
-type example_record() :: example_record.

CT

%%%-----------------------------------------------------------------------------
%%% @doc
%%% Common Tests built from template.
%%% @author <USER_NAME>
%%% @end
%%%-----------------------------------------------------------------------------

-module(<MODULE_NAME>).
-author("<USER_NAME>").

-include_lib("common_test/include/ct.hrl").
-include_lib("stdlib/include/assert.hrl").

%%%=============================================================================
%%% Export and Defs
%%%=============================================================================

-define(SERVER, ?MODULE).

-export([
	all/0, 
	init_per_suite/1, 
	init_per_testcase/2, 
	end_per_testcase/2, 
	end_per_suite/1
]).

-export([
    example_test/1
]).

%%%=============================================================================
%%% CT Functions
%%%=============================================================================

all() -> 
    [example_test].

init_per_suite(Config) ->
    Config.

init_per_testcase(_TestName, Config) ->
    Config.
 
end_per_testcase(_TestName, Config) ->
    Config.

end_per_suite(Config) ->
    Config.

%%%=============================================================================
%%% Tests
%%%=============================================================================

example_test(_Config) ->
	?assertEqual(true, true, <<"Example Comment">>).

%%%=============================================================================
%%% Internal functions
%%%=============================================================================

EScript

#!/opt/homebrew/opt/erlang@24/bin/escript
%% -*- erlang -*-

%%%=============================================================================
%%% EScript Functions
%%%=============================================================================

main(Inputs) ->
    try
        io:format("Inputs: ~p\n", [Inputs])
    catch
        Error:Reason ->
            io:format("Error: ~p, Reason: ~p\n", [Error, Reason]),
            usage()
    end;
main(_) ->
    usage().

usage() ->
    io:format("usage: <MODULE_NAME> <INPUT>\n"),
    halt(1).

%%%=============================================================================
%%% Internal Functions
%%%=============================================================================

Lager Handler

%%%-----------------------------------------------------------------------------
%%% @doc
%%% Lager Handler built from template
%%% @author <USER_NAME>
%%% @end
%%%-----------------------------------------------------------------------------

-module(<MODULE_NAME>).
-author("<USER_NAME>").
-behaviour(gen_event).

%%%=============================================================================
%%% Export and Defs
%%%=============================================================================

-define(SERVER, ?MODULE).

%% Websocket Callbacks
-export([
    init/1,
    handle_call/2,
    handle_event/2,
    handle_info/2,
    terminate/2,
    code_change/3
]).

%% Loop state
-record(state, {
    level :: integer()
}).
-type state() :: state.

%%%=============================================================================
%%% Lager Handler Callbacks
%%%=============================================================================

init([Level, _RetryTimes, _RetryInterval, _Token]) ->
    State = #state{
        level = lager_util:level_to_num(Level)
    },
    {ok, State}.

handle_call(get_loglevel, #state{level = Level} = State) ->
    {ok, Level, State};
handle_call({set_loglevel, Level}, State) ->
    {ok, ok, State#state{ level = lager_util:level_to_num(Level) }};
handle_call(_Request, State) ->
    {ok, ok, State}.

handle_event({log, _Message}, _State) ->
    ok;
handle_event(_Event, State) ->
    {ok, State}.

handle_info(_Info, State) ->
    {ok, State}.

terminate(_Reason, _State) ->
    ok.

code_change(_OldVsn, State, _Extra) ->
    {ok, State}.

%%%=============================================================================
%%% Internal functions
%%%=============================================================================

%%%=============================================================================
%%% Eunit Tests
%%%=============================================================================

-ifdef(TEST).

-include_lib("eunit/include/eunit.hrl").

example_test() ->
    ?assertEqual(true, true).

-endif.

Poolboy Worker

%%%-----------------------------------------------------------------------------
%%% @doc
%%% Poolboy Worker built from template.
%%% @author <USER_NAME>
%%% @end
%%%-----------------------------------------------------------------------------

-module(<MODULE_NAME>).
-author("<USER_NAME>").
-behaviour(poolboy_worker).

%%%=============================================================================
%%% Export and Defs
%%%=============================================================================

%% External API
-export([start_link/1]).

%% Callbacks
-export([
	init/1, 
	handle_call/3, 
	handle_cast/2, 
	handle_info/2,
	terminate/2, 
	code_change/3
]).

-define(SERVER, ?MODULE).

%% Loop state
-record(loop_state, {
	
}).
-type loop_state() :: loop_state.

%%%=============================================================================
%%% API
%%%=============================================================================

-spec start_link(map()) -> {ok, pid()} | {error, {already_started, pid()}} | {error, Reason::any()}.
start_link(Args) ->
	gen_server:start_link(?MODULE, Args, []).

%%%=============================================================================
%%% Callbacks
%%%=============================================================================

init(_Args) ->
	process_flag(trap_exit, true),
	{ok, #loop_state{}}.

handle_call(_Request, _From, LoopState) ->
	Reply = ok,
	{reply, Reply, LoopState}.

handle_cast(_Msg, LoopState) ->
	{noreply, LoopState}.

handle_info(_Info, LoopState) ->
	{noreply, LoopState}.

terminate(_Reason, _LoopState) ->
	ok.

code_change(_OldVsn, LoopState, _Extra) ->
	{ok, LoopState}.

%%%=============================================================================
%%% Internal functions
%%%=============================================================================

%%%=============================================================================
%%% Eunit Tests
%%%=============================================================================

-ifdef(TEST).

-include_lib("eunit/include/eunit.hrl").

example_test() ->
    ?assertEqual(true, true).

-endif.

Cowboy Rest Handler

%%%-----------------------------------------------------------------------------
%%% @doc
%%% Cowboy Rest Handler built from template.
%%% @author <USER_NAME>
%%% @end
%%%-----------------------------------------------------------------------------

-module(<MODULE_NAME>).
-author("<USER_NAME>").

%%%=============================================================================
%%% Export and Defs
%%%=============================================================================

%% Websocket Callbacks
-export([
    init/2,
	allowed_methods/2,
    content_types_provided/2,
    content_types_accepted/2
]).

%% Websocket Handlers
-export([
    get_function/2,
	put_function/2
]).

-define(SERVER, ?MODULE).

%% Loop state
-record(loop_state, {
	
}).
-type loop_state() :: loop_state.

%%%=============================================================================
%%% Cowboy Rest Handler Callbacks
%%%=============================================================================

init(Req, Opts) ->
	{cowboy_rest, Req, Opts}.

%%-----------------------------------------------------------------------------
%% @doc
%% REST methods supported by handler.
%% @end
%%-----------------------------------------------------------------------------
allowed_methods(Req, State) ->
	{[<<"GET">>, <<"POST">>, <<"OPTIONS">>], Req, State}.

%%-----------------------------------------------------------------------------
%% @doc
%% Define handler functions for GET and HEAD calls, with parameters if needed.
%% @end
%%-----------------------------------------------------------------------------
content_types_provided(Req, State) ->
	{[
		{{<<"text">>, <<"html">>, []}, get_function},
		{{<<"application">>, <<"json">>, []}, get_function},
		{{<<"text">>, <<"plain">>, []}, get_function}
	], Req, State}.



%%-----------------------------------------------------------------------------
%% @doc
%% Define handler functions for PUT?POST type calls, with parameters if needed.
%% @end
%%-----------------------------------------------------------------------------
content_types_accepted(Req, State) ->
	{[
		{{<<"text">>, <<"html">>, []}, put_function},
		{{<<"application">>, <<"json">>, []}, put_function},
		{{<<"text">>, <<"plain">>, []}, put_function}
	], Req, State}.

%%%=============================================================================
%%% Handlers
%%%=============================================================================

get_function(Req, State) ->
	{<<"">>, Req, State}.

put_function(Req, State) ->
	Req1 = cowboy_req:reply(200, #{}, <<"Response">>, Req),
    {stop, Req1, State}.

%%%=============================================================================
%%% Internal functions
%%%=============================================================================

%%%=============================================================================
%%% Eunit Tests
%%%=============================================================================

-ifdef(TEST).

-include_lib("eunit/include/eunit.hrl").

example_test() ->
    ?assertEqual(true, true).

-endif.

Cowboy Websocket Handler

%%%-----------------------------------------------------------------------------
%%% @doc
%%% Websockets Handler made from template
%%% @author <USER_NAME>
%%% @end
%%%-----------------------------------------------------------------------------

-module(<MODULE_NAME>).
-author("<USER_NAME>").

%%%=============================================================================
%%% Export and Defs
%%%=============================================================================

%% Websocket Callbacks
-export([
    init/2,
    websocket_init/1,
    websocket_handle/2,
    websocket_info/2,
    terminate/3
]).

-define(SERVER, ?MODULE).

%% Loop state
-record(loop_state, {
    ping_interval :: integer()
}).
-type loop_state() :: loop_state.

%%%=============================================================================
%%% Websocket Handler Callbacks
%%%=============================================================================

init(Req, [{ping_interval, Interval}]) ->
    {cowboy_websocket, Req, #loop_state{
        ping_interval = Interval
    }}.

websocket_init(LoopState = #loop_state{ping_interval = Interval}) ->
    erlang:start_timer(Interval, self(), ping),
    {reply, {binary, <<"ping">>}, LoopState}.

websocket_handle({_, <<"pong">>}, LoopState = #loop_state{ping_interval = Interval}) ->
    erlang:start_timer(Interval, self(), ping),
    {ok, LoopState};
websocket_handle(_Msg, LoopState) ->
    {ok, LoopState}.

websocket_info({timeout, _Ref, ping}, LoopState) ->
    {reply, {text, <<"ping">>}, LoopState};
websocket_info(_Info, State) ->
    {ok, State}.

terminate(_Reason, _Req, _LoopState) ->
    ok.

%%%=============================================================================
%%% Internal functions
%%%=============================================================================

%%%=============================================================================
%%% Eunit Tests
%%%=============================================================================

-ifdef(TEST).

-include_lib("eunit/include/eunit.hrl").

example_test() ->
    ?assertEqual(true, true).

-endif.

Snippets

print to console

Description: Log output to console

Command: log

io:format("~p~n", [$1]);
$2

receive

Description: receive block

Command: rec

receive
	$1 ->
		$2
end$3

receive with after

Description: receive block with after

Command: reca

receive
	$1 ->
		$2
after
	$3 ->
		$4
end$5

case

Description: case block

Command: case

case $1 of
	$2 ->
		$3
end$4

if

Description: if block

Command: if

if
	$1 ->
		$2
	true ->
		$3
end$4

Try

Description: try .. catch block

Command: try

try $1 of
	$2 ->
		$3
catch
	$4 ->
		$5
end$6

inline try/catch

Description: inline try .. catch block

Command: ?

try $1 catch $2 -> $4 end$5

eunit tests

Description: eunit tests section

Command: eunit

-ifdef(TEST).
-include_lib("eunit/include/eunit.hrl").
-endif.

%%%===================================================================
%%% Tests
%%%===================================================================

-ifdef(TEST).

$1_test() ->
	$2.

-endif.
$3

poolboy specs

Description: poolboy worker specs

Command: pools

{ok, Pools} = application:get_env($1, pools),
PoolSpecs = lists:map(fun({Name, SizeArgs, WorkerArgs}) ->
	WorkerImpl = proplists:get_value(worker_impl, WorkerArgs),
	PoolArgs = [{name, {local, Name}},
	{worker_module, WorkerImpl}] ++ SizeArgs,
	poolboy:child_spec(Name, PoolArgs, WorkerArgs)
end, Pools),
$2

cowboy web supervisor

Description: cowboy web supervisor

Command: cows

Dispatch = cowboy_router:compile([
	{'_', [
		{"/endpoint", endpoint, [{stats_interval, 10000}]}
	]}
]),
{ok, _} = cowboy:start_clear(
	http,
	[
		{port, $1}
	],
	#{env=>#{dispatch=>Dispatch}}
),
$2

worker child specs

Description: worker child specs

Command: works

#{
	id => $1,
	start => {$2, start_link, [$3]},
	restart => permanent,
	shutdown => brutal_kill,
	type => worker
}
$4

supervisor child specs

Description: worker child specs

Command: sups

#{
	id => $1,
	start => {$2, start_link, [$3]},
	restart => permanent,
	shutdown => brutal_kill,
	type => supervisor
}
$4

comment: section

Description: comment: section

Command: comsec

%%%=============================================================================
%%% $1
%%%=============================================================================
$2

comment: function

Description: comment: function

Command: funsec

%%------------------------------------------------------------------------------
%% @doc
%% $1
%% @end
%%------------------------------------------------------------------------------
$2

Erlang QoL

Nick

Erlang Quality of Life Improvements

Features

Side bar

Eunit testing

Code Generation and Snippets:

Docs

Comments

Header

Section

Function

Modules

Supervisor

Empty

Gen Server

Gen State Machine

Header

CT

EScript

Lager Handler

Poolboy Worker

Cowboy Rest Handler

Cowboy Websocket Handler

Snippets

print to console

Description: Log output to console

Command: log

receive

Description: receive block

Command: rec

receive with after

Description: receive block with after

Command: reca

case

Description: case block

Command: case

if

Description: if block

Command: if

Try

Description: try .. catch block

Command: try

inline try/catch

Description: inline try .. catch block

Command: ?

eunit tests

Description: eunit tests section

Command: eunit

poolboy specs

Description: poolboy worker specs

Command: pools

cowboy web supervisor

Description: cowboy web supervisor

Command: cows

worker child specs

Description: worker child specs

Command: works

supervisor child specs

Description: worker child specs

Command: sups

comment: section

Description: comment: section

Command: comsec

comment: function

Description: comment: function

Command: funsec