Remove quotes from keyspace names before sending them back in set_keyspace result messages

parser/lexer_test.go

@@ -86,11 +86,15 @@ func TestLexerIdentifiers(t *testing.T) {
 		{`"system"`, tkIdentifier, "system"},
 		{`"system"`, tkIdentifier, "system"},
 		{`"System"`, tkIdentifier, "System"},
-		{`""""`, tkIdentifier, "\""},
-		{`""""""`, tkIdentifier, "\"\""},
-		{`"A"""""`, tkIdentifier, "A\"\""},
-		{`"""A"""`, tkIdentifier, "\"A\""},
-		{`"""""A"`, tkIdentifier, "\"\"A"},
+		// below test verify correct escaping double quote character as per CQL definition:
+		//    identifier ::= unquoted_identifier | quoted_identifier
+		//    unquoted_identifier ::= re('[a-zA-Z][link:[a-zA-Z0-9]]*')
+		//    quoted_identifier ::= '"' (any character where " can appear if doubled)+ '"'
+		{`""""`, tkIdentifier, "\""},       // outermost quotes indicate quoted string, inner two double quotes shall be treated as single quote
+		{`""""""`, tkIdentifier, "\"\""},   // same as above, but 4 inner quotes result in 2 quotes
+		{`"A"""""`, tkIdentifier, "A\"\""}, // outermost quotes indicate quoted string, 4 quotes after A result in 2 quotes
+		{`"""A"""`, tkIdentifier, "\"A\""}, // outermost quotes indicate quoted string, 2 quotes before and after A result in single quotes
+		{`"""""A"`, tkIdentifier, "\"\"A"}, // analogical to previous tests
 		{`";`, tkInvalid, ""},
 		{`"""`, tkIdentifier, ""},
 	}

proxy/proxy.go

@@ -667,18 +667,17 @@ func (c *client) handleExecute(raw *frame.RawFrame, msg *partialExecute, customP
 }
 
 func (c *client) handleQuery(raw *frame.RawFrame, msg *partialQuery, customPayload map[string][]byte) {
-	c.proxy.logger.Debug("handling query", zap.String("query", msg.query), zap.Int16("stream", raw.Header.StreamId))
-
 	handled, stmt, err := parser.IsQueryHandled(parser.IdentifierFromString(c.keyspace), msg.query)
-
 	if handled {
+		c.proxy.logger.Debug("Query handled by proxy", zap.String("query", msg.query), zap.Int16("stream", raw.Header.StreamId))
 		if err != nil {
 			c.proxy.logger.Error("error parsing query to see if it's handled", zap.Error(err))
 			c.send(raw.Header, &message.Invalid{ErrorMessage: err.Error()})
 		} else {
 			c.interceptSystemQuery(raw.Header, stmt)
 		}
 	} else {
+		c.proxy.logger.Debug("Query not handled by proxy, forwarding", zap.String("query", msg.query), zap.Int16("stream", raw.Header.StreamId))
 		c.execute(raw, c.getDefaultIdempotency(customPayload), c.keyspace, msg)
 	}
 }
@@ -813,9 +812,20 @@ func (c *client) interceptSystemQuery(hdr *frame.Header, stmt interface{}) {
 		}
 	case *parser.UseStatement:
 		if _, err := c.proxy.maybeCreateSession(hdr.Version, s.Keyspace); err != nil {
-			c.send(hdr, &message.ServerError{ErrorMessage: "Proxy unable to create new session for keyspace"})
+			errMsg := "Proxy unable to create new session for keyspace"
+			var cqlError *proxycore.CqlError
+			if errors.As(err, &cqlError) {
+				// copy detailed error reason from downstream message
+				errMsg = cqlError.Message.GetErrorMessage()
+			}
+			c.send(hdr, &message.ServerError{ErrorMessage: errMsg})
 		} else {
 			c.keyspace = s.Keyspace
+			// We might have received a quoted keyspace name in the UseStatement so remove any
+			// quotes before sending back this result message.  This keeps us consistent with
+			// how Cassandra implements the same functionality and avoids any issues with
+			// drivers sending follow-on "USE" requests after wrapping the keyspace name in
+			// quotes.
 			ks := parser.IdentifierFromString(s.Keyspace)
 			c.send(hdr, &message.SetKeyspaceResult{Keyspace: ks.ID()})
 		}

proxy/proxy_test.go

@@ -206,13 +206,48 @@ func TestProxy_UseKeyspace(t *testing.T) {
 
 	cl := connectTestClient(t, ctx, proxyContactPoint)
 
-	resp, err := cl.SendAndReceive(ctx, frame.NewFrame(primitive.ProtocolVersion4, 0, &message.Query{Query: "USE system"}))
+	testKeyspaces := []string{"system", "\"system\""}
+	for _, testKeyspace := range testKeyspaces {
+
+		resp, err := cl.SendAndReceive(ctx, frame.NewFrame(primitive.ProtocolVersion4, 0, &message.Query{Query: "USE " + testKeyspace}))
+		require.NoError(t, err)
+
+		assert.Equal(t, primitive.OpCodeResult, resp.Header.OpCode)
+		res, ok := resp.Body.Message.(*message.SetKeyspaceResult)
+		require.True(t, ok, "expected set keyspace result")
+		assert.Equal(t, "system", res.Keyspace)
+	}
+}
+
+func TestProxy_UseKeyspace_Error(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	tester, proxyContactPoint, err := setupProxyTest(ctx, 1, proxycore.MockRequestHandlers{
+		primitive.OpCodeQuery: func(cl *proxycore.MockClient, frm *frame.Frame) message.Message {
+			qry := frm.Body.Message.(*message.Query)
+			if qry.Query == "USE non_existing" {
+				return &message.ServerError{
+					ErrorMessage: "Keyspace 'non_existing' does not exist",
+				}
+			}
+			return cl.InterceptQuery(frm.Header, frm.Body.Message.(*message.Query))
+		}})
+	defer func() {
+		cancel()
+		tester.shutdown()
+	}()
 	require.NoError(t, err)
 
-	assert.Equal(t, primitive.OpCodeResult, resp.Header.OpCode)
-	res, ok := resp.Body.Message.(*message.SetKeyspaceResult)
-	require.True(t, ok, "expected set keyspace result")
-	assert.Equal(t, "system", res.Keyspace)
+	cl := connectTestClient(t, ctx, proxyContactPoint)
+
+	resp, err := cl.SendAndReceive(ctx, frame.NewFrame(primitive.ProtocolVersion4, 0, &message.Query{Query: "USE non_existing"}))
+	require.NoError(t, err)
+
+	assert.Equal(t, primitive.OpCodeError, resp.Header.OpCode)
+	res, ok := resp.Body.Message.(*message.ServerError)
+	require.True(t, ok)
+	// make sure that CQL Proxy returns the same error of 'USE keyspace' command
+	// as backend C* cluster has and does not wrap it inside a custom one
+	assert.Equal(t, "Keyspace 'non_existing' does not exist", res.ErrorMessage)
 }
 
 func TestProxy_NegotiateProtocolV5(t *testing.T) {