internal: move {config,db,http} into internal

internal/http/query.go

@@ -0,0 +1,146 @@
+// Copyright 2014 The Cayley Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package http
+
+import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"net/http"
+
+	"github.com/julienschmidt/httprouter"
+
+	"github.com/google/cayley/query"
+	"github.com/google/cayley/query/gremlin"
+	"github.com/google/cayley/query/mql"
+)
+
+type SuccessQueryWrapper struct {
+	Result interface{} `json:"result"`
+}
+
+type ErrorQueryWrapper struct {
+	Error string `json:"error"`
+}
+
+func WrapErrResult(err error) ([]byte, error) {
+	var wrap ErrorQueryWrapper
+	wrap.Error = err.Error()
+	return json.MarshalIndent(wrap, "", " ")
+}
+
+func WrapResult(result interface{}) ([]byte, error) {
+	var wrap SuccessQueryWrapper
+	wrap.Result = result
+	return json.MarshalIndent(wrap, "", " ")
+}
+
+func Run(q string, ses query.HTTP) (interface{}, error) {
+	c := make(chan interface{}, 5)
+	go ses.Execute(q, c, 100)
+	for res := range c {
+		ses.Collate(res)
+	}
+	return ses.Results()
+}
+
+func GetQueryShape(q string, ses query.HTTP) ([]byte, error) {
+	s, err := ses.ShapeOf(q)
+	if err != nil {
+		return nil, err
+	}
+	return json.Marshal(s)
+}
+
+// TODO(barakmich): Turn this into proper middleware.
+func (api *API) ServeV1Query(w http.ResponseWriter, r *http.Request, params httprouter.Params) int {
+	h, err := api.GetHandleForRequest(r)
+	var ses query.HTTP
+	switch params.ByName("query_lang") {
+	case "gremlin":
+		ses = gremlin.NewSession(h.QuadStore, api.config.Timeout, false)
+	case "mql":
+		ses = mql.NewSession(h.QuadStore)
+	default:
+		return jsonResponse(w, 400, "Need a query language.")
+	}
+	bodyBytes, err := ioutil.ReadAll(r.Body)
+	if err != nil {
+		return jsonResponse(w, 400, err)
+	}
+	code := string(bodyBytes)
+	result, err := ses.Parse(code)
+	switch result {
+	case query.Parsed:
+		var output interface{}
+		var bytes []byte
+		var err error
+		output, err = Run(code, ses)
+		if err != nil {
+			bytes, err = WrapErrResult(err)
+			http.Error(w, string(bytes), 400)
+			ses = nil
+			return 400
+		}
+		bytes, err = WrapResult(output)
+		if err != nil {
+			ses = nil
+			return jsonResponse(w, 400, err)
+		}
+		fmt.Fprint(w, string(bytes))
+		ses = nil
+		return 200
+	case query.ParseFail:
+		ses = nil
+		return jsonResponse(w, 400, err)
+	default:
+		ses = nil
+		return jsonResponse(w, 500, "Incomplete data?")
+	}
+}
+
+func (api *API) ServeV1Shape(w http.ResponseWriter, r *http.Request, params httprouter.Params) int {
+	h, err := api.GetHandleForRequest(r)
+	var ses query.HTTP
+	switch params.ByName("query_lang") {
+	case "gremlin":
+		ses = gremlin.NewSession(h.QuadStore, api.config.Timeout, false)
+	case "mql":
+		ses = mql.NewSession(h.QuadStore)
+	default:
+		return jsonResponse(w, 400, "Need a query language.")
+	}
+	bodyBytes, err := ioutil.ReadAll(r.Body)
+	if err != nil {
+		return jsonResponse(w, 400, err)
+	}
+	code := string(bodyBytes)
+	result, err := ses.Parse(code)
+	switch result {
+	case query.Parsed:
+		var output []byte
+		var err error
+		output, err = GetQueryShape(code, ses)
+		if err != nil {
+			return jsonResponse(w, 400, err)
+		}
+		fmt.Fprint(w, string(output))
+		return 200
+	case query.ParseFail:
+		return jsonResponse(w, 400, err)
+	default:
+		return jsonResponse(w, 500, "Incomplete data?")
+	}
+}