func queryHandler(w http.ResponseWriter, r *http.Request) {
addCorsHeaders(w)
if r.Method == "OPTIONS" {
return
}
if r.Method != "POST" {
x.SetStatus(w, x.E_INVALID_METHOD, "Invalid method")
return
}
var l query.Latency
l.Start = time.Now()
defer r.Body.Close()
q, err := ioutil.ReadAll(r.Body)
if err != nil || len(q) == 0 {
x.Err(glog, err).Error("While reading query")
x.SetStatus(w, x.E_INVALID_REQUEST, "Invalid request encountered.")
return
}
glog.WithField("q", string(q)).Debug("Query received.")
sg, err := gql.Parse(string(q))
if err != nil {
x.Err(glog, err).Error("While parsing query")
x.SetStatus(w, x.E_INVALID_REQUEST, err.Error())
return
}
l.Parsing = time.Since(l.Start)
glog.WithField("q", string(q)).Debug("Query parsed.")
rch := make(chan error)
go query.ProcessGraph(sg, rch)
err = <-rch
if err != nil {
x.Err(glog, err).Error("While executing query")
x.SetStatus(w, x.E_ERROR, err.Error())
return
}
l.Processing = time.Since(l.Start) - l.Parsing
glog.WithField("q", string(q)).Debug("Graph processed.")
js, err := sg.ToJson(&l)
if err != nil {
x.Err(glog, err).Error("While converting to Json.")
x.SetStatus(w, x.E_ERROR, err.Error())
return
}
glog.WithFields(logrus.Fields{
"total": time.Since(l.Start),
"parsing": l.Parsing,
"process": l.Processing,
"json": l.Json,
}).Info("Query Latencies")
w.Header().Set("Content-Type", "application/json")
fmt.Fprint(w, string(js))
}
// This method is used to execute the query and return the response to the
// client as a protocol buffer message.
func (s *grpcServer) Query(ctx context.Context,
req *graph.Request) (*graph.Response, error) {
var allocIds map[string]uint64
if rand.Float64() < *tracing {
tr := trace.New("Dgraph", "GrpcQuery")
defer tr.Finish()
ctx = trace.NewContext(ctx, tr)
}
resp := new(graph.Response)
if len(req.Query) == 0 && req.Mutation == nil {
x.TraceError(ctx, x.Errorf("Empty query and mutation."))
return resp, fmt.Errorf("Empty query and mutation.")
}
var l query.Latency
l.Start = time.Now()
x.Trace(ctx, "Query received: %v", req.Query)
gq, mu, err := gql.Parse(req.Query)
if err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while parsing query"))
return resp, err
}
// If mutations are part of the query, we run them through the mutation handler
// same as the http client.
if mu != nil && (len(mu.Set) > 0 || len(mu.Del) > 0) {
if allocIds, err = mutationHandler(ctx, mu); err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while handling mutations"))
return resp, err
}
}
// If mutations are sent as part of the mutation object in the request we run
// them here.
if req.Mutation != nil && (len(req.Mutation.Set) > 0 || len(req.Mutation.Del) > 0) {
if allocIds, err = runMutations(ctx, req.Mutation); err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while handling mutations"))
return resp, err
}
}
resp.AssignedUids = allocIds
if gq == nil || (gq.UID == 0 && len(gq.XID) == 0) {
return resp, err
}
sg, err := query.ToSubGraph(ctx, gq)
if err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while conversion to internal format"))
return resp, err
}
l.Parsing = time.Since(l.Start)
x.Trace(ctx, "Query parsed")
rch := make(chan error)
go query.ProcessGraph(ctx, sg, nil, rch)
err = <-rch
if err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while executing query"))
return resp, err
}
l.Processing = time.Since(l.Start) - l.Parsing
x.Trace(ctx, "Graph processed")
node, err := sg.ToProtocolBuffer(&l)
if err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while converting to ProtocolBuffer"))
return resp, err
}
resp.N = node
gl := new(graph.Latency)
gl.Parsing, gl.Processing, gl.Pb = l.Parsing.String(), l.Processing.String(),
l.ProtocolBuffer.String()
resp.L = gl
return resp, err
}
func queryHandler(w http.ResponseWriter, r *http.Request) {
// Add a limit on how many pending queries can be run in the system.
pendingQueries <- struct{}{}
defer func() { <-pendingQueries }()
addCorsHeaders(w)
if r.Method == "OPTIONS" {
return
}
if r.Method != "POST" {
x.SetStatus(w, x.ErrorInvalidMethod, "Invalid method")
return
}
ctx, cancel := context.WithTimeout(context.Background(), time.Minute)
defer cancel()
if rand.Float64() < *tracing {
tr := trace.New("Dgraph", "Query")
defer tr.Finish()
ctx = trace.NewContext(ctx, tr)
}
var l query.Latency
l.Start = time.Now()
defer r.Body.Close()
req, err := ioutil.ReadAll(r.Body)
q := string(req)
if err != nil || len(q) == 0 {
x.TraceError(ctx, x.Wrapf(err, "Error while reading query"))
x.SetStatus(w, x.ErrorInvalidRequest, "Invalid request encountered.")
return
}
x.Trace(ctx, "Query received: %v", q)
gq, mu, err := gql.Parse(q)
if err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while parsing query"))
x.SetStatus(w, x.ErrorInvalidRequest, err.Error())
return
}
var allocIds map[string]uint64
var allocIdsStr map[string]string
// If we have mutations, run them first.
if mu != nil && (len(mu.Set) > 0 || len(mu.Del) > 0) {
if allocIds, err = mutationHandler(ctx, mu); err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while handling mutations"))
x.SetStatus(w, x.Error, err.Error())
return
}
// convert the new UIDs to hex string.
allocIdsStr = make(map[string]string)
for k, v := range allocIds {
allocIdsStr[k] = fmt.Sprintf("%#x", v)
}
}
if gq == nil || (gq.UID == 0 && gq.Func == nil && len(gq.XID) == 0) {
mp := map[string]interface{}{
"code": x.ErrorOk,
"message": "Done",
"uids": allocIdsStr,
}
if js, err := json.Marshal(mp); err == nil {
w.Write(js)
} else {
x.SetStatus(w, "Error", "Unable to marshal map")
}
return
}
sg, err := query.ToSubGraph(ctx, gq)
if err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while conversion o internal format"))
x.SetStatus(w, x.ErrorInvalidRequest, err.Error())
return
}
l.Parsing = time.Since(l.Start)
x.Trace(ctx, "Query parsed")
rch := make(chan error)
go query.ProcessGraph(ctx, sg, nil, rch)
err = <-rch
if err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while executing query"))
x.SetStatus(w, x.Error, err.Error())
return
}
l.Processing = time.Since(l.Start) - l.Parsing
x.Trace(ctx, "Graph processed")
if len(*dumpSubgraph) > 0 {
x.Checkf(os.MkdirAll(*dumpSubgraph, 0700), *dumpSubgraph)
s := time.Now().Format("20060102.150405.000000.gob")
filename := path.Join(*dumpSubgraph, s)
f, err := os.Create(filename)
x.Checkf(err, filename)
enc := gob.NewEncoder(f)
x.Check(enc.Encode(sg))
x.Checkf(f.Close(), filename)
}
js, err := sg.ToJSON(&l)
if err != nil {
x.TraceError(ctx, x.Wrapf(err, "Error while converting to Json"))
x.SetStatus(w, x.Error, err.Error())
return
}
x.Trace(ctx, "Latencies: Total: %v Parsing: %v Process: %v Json: %v",
time.Since(l.Start), l.Parsing, l.Processing, l.Json)
w.Header().Set("Content-Type", "application/json")
w.Write(js)
}