fix(GraphQL): Pass on HTTP request headers for subscriptions

go.mod

@@ -21,7 +21,7 @@ require (
 	github.com/dgraph-io/dgo/v210 v210.0.0-20210407152819-261d1c2a6987
 	github.com/dgraph-io/gqlgen v0.13.2
 	github.com/dgraph-io/gqlparser/v2 v2.2.0
-	github.com/dgraph-io/graphql-transport-ws v0.0.0-20210223074046-e5b8b80bb4ed
+	github.com/dgraph-io/graphql-transport-ws v0.0.0-20210511143556-2cef522f1f15
 	github.com/dgraph-io/ristretto v0.0.4-0.20210504190834-0bf2acd73aa3
 	github.com/dgraph-io/roaring v0.5.6-0.20210227175938-766b897233a5
 	github.com/dgraph-io/simdjson-go v0.3.0

go.sum

@@ -131,6 +131,8 @@ github.com/dgraph-io/gqlparser/v2 v2.2.0 h1:fKSCW8OxoMogjDwUhO9OrFvrgIA0UZspTDbc
 github.com/dgraph-io/gqlparser/v2 v2.2.0/go.mod h1:MYS4jppjyx8b9tuUtjV7jU1UFZK6P9fvO8TsIsQtRKU=
 github.com/dgraph-io/graphql-transport-ws v0.0.0-20210223074046-e5b8b80bb4ed h1:pgGMBoTtFhR+xkyzINaToLYRurHn+6pxMYffIGmmEPc=
 github.com/dgraph-io/graphql-transport-ws v0.0.0-20210223074046-e5b8b80bb4ed/go.mod h1:7z3c/5w0sMYYZF5bHsrh8IH4fKwG5O5Y70cPH1ZLLRQ=
+github.com/dgraph-io/graphql-transport-ws v0.0.0-20210511143556-2cef522f1f15 h1:X2NRsgAtVUAp2nmTPCq+x+wTcRRrj74CEpy7E0Unsl4=
+github.com/dgraph-io/graphql-transport-ws v0.0.0-20210511143556-2cef522f1f15/go.mod h1:7z3c/5w0sMYYZF5bHsrh8IH4fKwG5O5Y70cPH1ZLLRQ=
 github.com/dgraph-io/ristretto v0.0.4-0.20210504190834-0bf2acd73aa3 h1:jU/wpYsEL+8JPLf/QcjkQKI5g0dOjSuwcMjkThxt5x0=
 github.com/dgraph-io/ristretto v0.0.4-0.20210504190834-0bf2acd73aa3/go.mod h1:fux0lOrBhrVCJd3lcTHsIJhq1T2rokOu6v9Vcb3Q9ug=
 github.com/dgraph-io/roaring v0.5.6-0.20210227175938-766b897233a5 h1:9t3OKcvsQlxU9Cu0U55tgvNtaRYVGDr6rUb95P8cSbg=

graphql/admin/http.go

@@ -158,10 +158,10 @@ func (gs *graphqlSubscription) Subscribe(
 	variableValues map[string]interface{}) (payloads <-chan interface{},
 	err error) {
 
+	reqHeader := http.Header{}
 	// library (graphql-transport-ws) passes the headers which are part of the INIT payload to us
 	// in the context. We are extracting those headers and passing them along.
 	headerPayload, _ := ctx.Value("Header").(json.RawMessage)
-	reqHeader := http.Header{}
 	if len(headerPayload) > 0 {
 		headers := make(map[string]interface{})
 		if err = json.Unmarshal(headerPayload, &headers); err != nil {
@@ -175,14 +175,35 @@ func (gs *graphqlSubscription) Subscribe(
 		}
 	}
 
+	// Earlier the graphql-transport-ws library was ignoring the http headers in the request.
+	// The library was relying upon the information present in the request payload. This was
+	// blocker for the cloud team because the only control cloud has is over the HTTP headers.
+	// This fix ensures that we are setting the request headers if not provided in the payload.
+	headerPayload, _ = ctx.Value("RequestHeader").(json.RawMessage)
+	if len(headerPayload) > 0 {
+		headers := http.Header{}
+		if err = json.Unmarshal(headerPayload, &headers); err != nil {
+			return nil, err
+		}
+		for k := range headers {
+			if len(strings.TrimSpace(reqHeader.Get(k))) == 0 {
+				reqHeader.Set(k, headers.Get(k))
+			}
+		}
+	}
+
 	req := &schema.Request{
 		OperationName: operationName,
 		Query:         document,
 		Variables:     variableValues,
 		Header:        reqHeader,
 	}
 	namespace := x.ExtractNamespaceHTTP(&http.Request{Header: reqHeader})
-	LazyLoadSchema(namespace) // first load the schema, then do anything else
+	glog.Infof("namespace: %d. Got GraphQL request over websocket.", namespace)
+	// first load the schema, then do anything else
+	if err = LazyLoadSchema(namespace); err != nil {
+		return nil, err
+	}
 	if err = gs.isValid(namespace); err != nil {
 		glog.Errorf("namespace: %d. graphqlSubscription not initialized: %s", namespace, err)
 		return nil, errors.New(resolve.ErrInternal)
@@ -220,6 +241,7 @@ func (gh *graphqlHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 	defer span.End()
 
 	ns, _ := strconv.ParseUint(r.Header.Get("resolver"), 10, 64)
+	glog.Infof("namespace: %d. Got GraphQL request over HTTP.", ns)
 	if err := gh.isValid(ns); err != nil {
 		glog.Errorf("namespace: %d. graphqlHandler not initialised: %s", ns, err)
 		WriteErrorResponse(w, r, errors.New(resolve.ErrInternal))