fix(codec): parse WebSocket responses independent of JSON field order

Author: magnusp

libsql-hrana-codec/src/main/java/com/github/magnusp/libsql/hrana/codec/DirectHranaJsonCodec.java

@@ -689,31 +689,40 @@ public WsServerMsg deserialize(byte[] payload) throws IOException {
     }
 
     private WsResponse parseWsResponse(FastJsonParser p) throws IOException {
+        // JSON object field order is not significant, so find the type before reading the payload.
+        int start = p.pos;
         p.expectObjectStart();
         String type = null;
-        StmtResult stmtResult = null;
-        BatchResult batchResult = null;
-
         while (!p.checkObjectEnd()) {
             String field = p.nextFieldName();
-            switch (field) {
-                case "type" -> type = p.nextString();
-                case "result" -> {
-                    if ("execute".equals(type)) {
-                        stmtResult = parseStmtResult(p);
-                    } else if ("batch".equals(type)) {
-                        batchResult = parseBatchResult(p);
-                    } else {
-                        p.skipValue();
-                    }
-                }
-                default -> p.skipValue();
+            if ("type".equals(field)) {
+                type = p.nextString();
+            } else {
+                p.skipValue();
             }
         }
-
         if (type == null) {
             throw new IOException("WebSocket response missing type field");
         }
+
+        p.pos = start;
+        p.expectObjectStart();
+        StmtResult stmtResult = null;
+        BatchResult batchResult = null;
+        while (!p.checkObjectEnd()) {
+            String field = p.nextFieldName();
+            if ("result".equals(field)) {
+                if ("execute".equals(type)) {
+                    stmtResult = parseStmtResult(p);
+                } else if ("batch".equals(type)) {
+                    batchResult = parseBatchResult(p);
+                } else {
+                    p.skipValue();
+                }
+            } else {
+                p.skipValue();
+            }
+        }
         return switch (type) {
             case "open_stream" -> WsResponse.OpenStream.INSTANCE;
             case "close_stream" -> WsResponse.CloseStream.INSTANCE;

libsql-hrana-codec/src/test/java/com/github/magnusp/libsql/hrana/codec/DirectHranaWsJsonCodecTest.java

@@ -160,6 +160,18 @@ void deserializesBatchResponse() throws IOException {
                 .isEqualTo(new WsServerMsg.ResponseOk(12, new WsResponse.Batch(expected)));
     }
 
+    @Test
+    void deserializesExecuteResponseRegardlessOfFieldOrder() throws IOException {
+        String json = """
+                {"response":{"result":{"cols":[],"rows":[],"affected_row_count":0},
+                "type":"execute"},"request_id":14,"type":"response_ok"}""";
+
+        StmtResult expected = new StmtResult(List.of(), List.of(), 0, null);
+
+        assertThat(codec.deserialize(utf8(json)))
+                .isEqualTo(new WsServerMsg.ResponseOk(14, new WsResponse.Execute(expected)));
+    }
+
     @Test
     void deserializesResponseError() throws IOException {
         assertThat(codec.deserialize(utf8(