DC-118: Health check (#33)

* added health check

* fix

* minor

* fix

* fixed cfg

* removed has version api

* changed transport opts

* refixed transport opts

* added requested changes

* fixed

* minor

config/sys.config

@@ -1,10 +1,35 @@
 [
     {dmt_client, [
-        {transport_opts, #{
+        {ip, "::"},
+        {port, 8022},
+        %% 1 sec above cowboy's request_timeout
+        {shutdown_timeout, 7000},
+        {protocol_opts, #{
+            % Bump keepalive timeout up to a minute
+            request_timeout => 6000,
+            % Should be greater than any other timeouts
+            idle_timeout => infinity
+        }},
+        {server_transport_opts, #{
+            % Keeping the default value
+            max_connections => 8096
+        }},
+        {client_transport_opts, #{
             recv_timeout => 60000,
             connect_timeout => 1000
         }},
-        {woody_event_handlers, [
+        {server_woody_event_handlers, [
+            {scoper_woody_event_handler, #{
+                event_handler_opts => #{
+                    formatter_opts => #{
+                        max_length => 1000,
+                        max_depth => 10,
+                        max_pritable_string_length => 40
+                    }
+                }
+            }}
+        ]},
+        {client_woody_event_handlers, [
             {scoper_woody_event_handler, #{
                 event_handler_opts => #{
                     formatter_opts => #{
@@ -23,6 +48,10 @@
         {service_urls, #{
             'Repository' => <<"dominant:8022/v1/domain/repository">>,
             'RepositoryClient' => <<"dominant:8022/v1/domain/repository_client">>
+        }},
+        {health_check, #{
+            dmt_client => {dmt_client, health_check, []},
+            service => {erl_health, service, [<<"dmt_client">>]}
         }}
     ]}
 ].

rebar.config

@@ -27,10 +27,11 @@
 
 %% Common project dependencies.
 {deps, [
-    {genlib,      {git, "https://github.com/rbkmoney/genlib.git",      {branch, "master"}}},
-    {woody ,      {git, "git@github.com:rbkmoney/woody_erlang.git",    {branch, "master"}}},
-    {dmt_core,    {git, "git@github.com:rbkmoney/dmt_core.git",        {branch, "master"}}},
-    {damsel,      {git, "git@github.com:rbkmoney/damsel.git",          {branch, "release/erlang/master"}}}
+    {genlib,      {git, "https://github.com/rbkmoney/genlib.git",           {branch, "master"}}},
+    {woody ,      {git, "git@github.com:rbkmoney/woody_erlang.git",         {branch, "master"}}},
+    {dmt_core,    {git, "git@github.com:rbkmoney/dmt_core.git",             {branch, "master"}}},
+    {erl_health,  {git, "https://github.com/rbkmoney/erlang-health.git",    {branch, "master"}}},
+    {damsel,      {git, "git@github.com:rbkmoney/damsel.git",               {branch, "release/erlang/master"}}}
 ]}.
 
 %% XRef checks

rebar.lock

@@ -3,9 +3,9 @@
  {<<"cache">>,{pkg,<<"cache">>,<<"2.2.0">>},1},
  {<<"certifi">>,{pkg,<<"certifi">>,<<"2.5.1">>},2},
  {<<"cg_mon">>,
-  {git,"git@github.com:rbkmoney/cg_mon.git",
+  {git,"https://github.com/rbkmoney/cg_mon.git",
        {ref,"5a87a37694e42b6592d3b4164ae54e0e87e24e18"}},
-  2},
+  1},
  {<<"cowboy">>,{pkg,<<"cowboy">>,<<"2.5.0">>},1},
  {<<"cowlib">>,{pkg,<<"cowlib">>,<<"2.6.0">>},2},
  {<<"damsel">>,
@@ -16,6 +16,10 @@
   {git,"git@github.com:rbkmoney/dmt_core.git",
        {ref,"8ac78cb1c94abdcdda6675dd7519893626567573"}},
   0},
+ {<<"erl_health">>,
+  {git,"https://github.com/rbkmoney/erlang-health.git",
+       {ref,"3a80bb43a93eb0e7a940d19912d9e35c2cbe91f9"}},
+  0},
  {<<"folsom">>,
   {git,"git@github.com:folsom-project/folsom.git",
        {ref,"9309bad9ffadeebbefe97521577c7480c7cfcd8a"}},
@@ -31,6 +35,7 @@
        {ref,"2bb46054e16aaba9357747cc72b7c42e1897a56d"}},
   1},
  {<<"idna">>,{pkg,<<"idna">>,<<"6.0.0">>},2},
+ {<<"jsx">>,{pkg,<<"jsx">>,<<"2.8.0">>},1},
  {<<"metrics">>,{pkg,<<"metrics">>,<<"1.0.1">>},2},
  {<<"mimerl">>,{pkg,<<"mimerl">>,<<"1.2.0">>},2},
  {<<"parse_trans">>,{pkg,<<"parse_trans">>,<<"3.3.0">>},3},
@@ -60,6 +65,7 @@
  {<<"gproc">>, <<"CEA02C578589C61E5341FCE149EA36CCEF236CC2ECAC8691FBA408E7EA77EC2F">>},
  {<<"hackney">>, <<"07E33C794F8F8964EE86CEBEC1A8ED88DB5070E52E904B8F12209773C1036085">>},
  {<<"idna">>, <<"689C46CBCDF3524C44D5F3DDE8001F364CD7608A99556D8FBD8239A5798D4C10">>},
+ {<<"jsx">>, <<"749BEC6D205C694AE1786D62CEA6CC45A390437E24835FD16D12D74F07097727">>},
  {<<"metrics">>, <<"25F094DEA2CDA98213CECC3AEFF09E940299D950904393B2A29D191C346A8486">>},
  {<<"mimerl">>, <<"67E2D3F571088D5CFD3E550C383094B47159F3EEE8FFA08E64106CDF5E981BE3">>},
  {<<"parse_trans">>, <<"09765507A3C7590A784615CFD421D101AEC25098D50B89D7AA1D66646BC571C1">>},

src/dmt_client.app.src

@@ -6,7 +6,8 @@
         kernel,
         stdlib,
         woody,
-        dmt_core
+        dmt_core,
+        erl_health
     ]},
     {mod, {dmt_client, []}},
     {env, []}

src/dmt_client.erl

@@ -16,6 +16,9 @@
 -export([pull_range/2]).
 -export([pull_range/3]).
 
+%% Health check API
+-export([health_check/0]).
+
 %% Supervisor callbacks
 -export([init/1]).
 
@@ -117,13 +120,60 @@ pull_range(Version, Limit) ->
 pull_range(Version, Limit, Opts) ->
     dmt_client_backend:pull_range(Version, Limit, Opts).
 
+%% Health check API
+
+-spec health_check() ->
+    erl_health:result().
+
+health_check() ->
+    try
+        _ = dmt_client_cache:get_last_version(),
+        {passing, #{}}
+    catch
+        _Class:_Error ->
+            {critical, #{last_version => not_found}}
+    end.
+
 %%% Supervisor callbacks
 
 -spec init([]) -> {ok, {supervisor:sup_flags(), [supervisor:child_spec()]}}.
 
 init([]) ->
     Cache = #{id => dmt_client_cache, start => {dmt_client_cache, start_link, []}, restart => permanent},
-    {ok, {#{strategy => one_for_one, intensity => 10, period => 60}, [Cache]}}.
+    {ok, {#{
+        strategy => one_for_one, intensity => 10, period => 60},
+        [
+            Cache,
+            get_health_spec()
+        ]
+    }}.
+
+get_health_spec() ->
+    {ok, Ip} = inet:parse_address(genlib_app:env(?MODULE, ip, "::")),
+    HealthRoutes = construct_health_routes(genlib_app:env(?MODULE, health_check, #{})),
+    woody_server:child_spec(
+        ?MODULE,
+        #{
+            ip                  => Ip,
+            port                => genlib_app:env(?MODULE, port, 8022),
+            transport_opts      => genlib_app:env(?MODULE, server_transport_opts, #{}),
+            protocol_opts       => genlib_app:env(?MODULE, protocol_opts, #{}),
+            event_handler       => get_event_handlers(),
+            handlers            => [],
+            additional_routes   => HealthRoutes,
+            shutdown_timeout    => genlib_app:env(?MODULE, shutdown_timeout, 0)
+        }
+    ).
+
+get_event_handlers() ->
+    genlib_app:env(dmt_client, server_woody_event_handlers, []).
+
+construct_health_routes(Check) ->
+    [erl_health_handle:get_route(enable_health_logging(Check))].
+
+enable_health_logging(Check) ->
+    EvHandler = {erl_health_event_handler, []},
+    maps:map(fun (_, V = {_, _, _}) -> #{runner => V, event_handler => EvHandler} end, Check).
 
 %%% Application callbacks
 

src/dmt_client_api.erl

@@ -61,7 +61,7 @@ get_service_module('RepositoryClient') ->
     dmsl_domain_config_thrift.
 
 get_event_handlers() ->
-    genlib_app:env(dmt_client, woody_event_handlers, []).
+    genlib_app:env(dmt_client, client_woody_event_handlers, []).
 
 -spec ensure_transport_opts(dmt_client:transport_opts()) ->
     woody_client_thrift_http_transport:transport_options().
@@ -70,4 +70,4 @@ ensure_transport_opts(Opts) when is_map(Opts) ->
     Opts;
 ensure_transport_opts(undefined) ->
     Default = #{recv_timeout => 60000, connect_timeout => 1000},
-    genlib_app:env(dmt_client, transport_opts, Default).
+    genlib_app:env(dmt_client, client_transport_opts, Default).