Add src/hk_api_search_h.erl

src/hk_api_search_h.erl

@@ -0,0 +1,77 @@
+%%%-------------------------------------------------------------------
+%%% @doc `/search' API domain.
+%%%
+%%%   POST /api/search             start a job (async, returns job_id immediately)
+%%%   GET  /api/search             list jobs (current stage/iteration each)
+%%%   GET  /api/search/:id         describe one job's current stage
+%%%   GET  /api/search/:id/result  final result if `done'; 202 (pending) otherwise
+%%%
+%%% Progress between "started" and "result ready" is observed via
+%%% the `search.*' events on the event stream, per the pipeline's
+%%% event-per-stage requirement -- this handler does not poll or
+%%% block waiting for the pipeline itself.
+%%% @end
+%%%-------------------------------------------------------------------
+-module(hk_api_search_h).
+
+-export([init/2]).
+
+init(Req0 = #{method := <<"POST">>}, collection) ->
+    RequestId = hk_api_util:request_id(Req0),
+    {ok, Body, Req1} = hk_api_util:read_json_body(Req0),
+    OwnerAgentId = maps:get(<<"owner_agent_id">>, Body, undefined),
+    Query = maps:get(<<"query">>, Body, <<>>),
+    MaxIterations = maps:get(<<"max_iterations">>, Body, 3),
+    Req = hk_api_util:run_operation(search_start, RequestId, fun() ->
+        case hk_search:start(OwnerAgentId, Query, #{max_iterations => MaxIterations}) of
+            {ok, JobId} -> {ok, {search_job, JobId}, #{job_id => JobId}};
+            {error, Reason} -> {error, Reason}
+        end
+    end, Req1),
+    {ok, Req, collection};
+
+init(Req0 = #{method := <<"GET">>}, collection) ->
+    Jobs = [describe_or_skip(Id) || {Id, _Pid} <- hk_search_registry:list_jobs()],
+    Req = hk_api_util:reply_json(200, #{jobs => [M || {true, M} <- Jobs]}, Req0),
+    {ok, Req, collection};
+
+init(Req0 = #{method := <<"GET">>}, item) ->
+    JobId = cowboy_req:binding(id, Req0),
+    Req = case hk_search_registry:lookup(JobId) of
+              {ok, Pid} ->
+                  {ok, Job} = hk_search_job:describe(Pid),
+                  hk_api_util:reply_json(200, hk_schema:to_map(Job), Req0);
+              {error, not_found} ->
+                  hk_api_util:reply_error(404, job_not_found, Req0)
+          end,
+    {ok, Req, item};
+
+init(Req0 = #{method := <<"GET">>}, result) ->
+    JobId = cowboy_req:binding(id, Req0),
+    Req = case hk_search_registry:lookup(JobId) of
+              {ok, Pid} ->
+                  case hk_search_job:await_result(Pid, 300) of
+                      {ok, Result} -> hk_api_util:reply_json(200, Result, Req0);
+                      {error, pending} -> hk_api_util:reply_json(202, #{status => pending}, Req0);
+                      {error, Reason} -> hk_api_util:reply_error(422, Reason, Req0)
+                  end;
+              {error, not_found} ->
+                  hk_api_util:reply_error(404, job_not_found, Req0)
+          end,
+    {ok, Req, result};
+
+init(Req0, State) ->
+    Req = hk_api_util:reply_error(405, method_not_allowed, Req0),
+    {ok, Req, State}.
+
+%%% internal
+
+describe_or_skip(JobId) ->
+    case hk_search_registry:lookup(JobId) of
+        {ok, Pid} ->
+            case catch hk_search_job:describe(Pid) of
+                {ok, Job} -> {true, hk_schema:to_map(Job)};
+                _ -> false
+            end;
+        _ -> false
+    end.