Add a query API to the roomserver for getting the latest events in a room. (#23)

* Start implementing a query API for go using net/rpc

* Use a conventional JSON POST API rather than go net/rpc

net/rpc doesn't automatically handle reconnecting and we have better
logging and metrics infrastructure for monitoring HTTP apis.

* Implement the query API and add it to the integration tests

* Increase the timeout, travis seems to be a bit slow

* Clarify that state events are the things that are not returned if they are not requested

* Add utility function for converting arrays of numeric event IDs to pq Int64Arrays

* Warn people against requesting empty state keys by accident

vendor/manifest

@@ -98,7 +98,7 @@
 		{
 			"importpath": "github.com/matrix-org/util",
 			"repository": "https://github.com/matrix-org/util",
-			"revision": "ccef6dc7c24a7c896d96b433a9107b7c47ecf828",
+			"revision": "28bd7491c8aafbf346ca23821664f0f9911ef52b",
 			"branch": "master"
 		},
 		{
@@ -206,4 +206,4 @@
 			"branch": "master"
 		}
 	]
-}
+}

vendor/src/github.com/matrix-org/util/context.go

@@ -25,11 +25,13 @@ func GetRequestID(ctx context.Context) string {
 // ctxValueLogger is the key to extract the logrus Logger.
 const ctxValueLogger = contextKeys("logger")
 
-// GetLogger retrieves the logrus logger from the supplied context. Returns nil if there is no logger.
+// GetLogger retrieves the logrus logger from the supplied context. Always returns a logger,
+// even if there wasn't one originally supplied.
 func GetLogger(ctx context.Context) *log.Entry {
 	l := ctx.Value(ctxValueLogger)
 	if l == nil {
-		return nil
+		// Always return a logger so callers don't need to constantly nil check.
+		return log.WithField("context", "missing")
 	}
 	return l.(*log.Entry)
 }

vendor/src/github.com/matrix-org/util/json.go

@@ -58,6 +58,21 @@ type JSONRequestHandler interface {
 	OnIncomingRequest(req *http.Request) JSONResponse
 }
 
+// jsonRequestHandlerWrapper is a wrapper to allow in-line functions to conform to util.JSONRequestHandler
+type jsonRequestHandlerWrapper struct {
+	function func(req *http.Request) JSONResponse
+}
+
+// OnIncomingRequest implements util.JSONRequestHandler
+func (r *jsonRequestHandlerWrapper) OnIncomingRequest(req *http.Request) JSONResponse {
+	return r.function(req)
+}
+
+// NewJSONRequestHandler converts the given OnIncomingRequest function into a JSONRequestHandler
+func NewJSONRequestHandler(f func(req *http.Request) JSONResponse) JSONRequestHandler {
+	return &jsonRequestHandlerWrapper{f}
+}
+
 // Protect panicking HTTP requests from taking down the entire process, and log them using
 // the correct logger, returning a 500 with a JSON response rather than abruptly closing the
 // connection. The http.Request MUST have a ctxValueLogger.

vendor/src/github.com/matrix-org/util/json_test.go

@@ -164,8 +164,8 @@ func TestGetLogger(t *testing.T) {
 
 	noLoggerInReq, _ := http.NewRequest("GET", "http://example.com/foo", nil)
 	ctxLogger = GetLogger(noLoggerInReq.Context())
-	if ctxLogger != nil {
-		t.Errorf("TestGetLogger wanted nil logger, got '%v'", ctxLogger)
+	if ctxLogger == nil {
+		t.Errorf("TestGetLogger wanted logger, got nil")
 	}
 }