Better json handling (#707)

* Better json handling.

* Backend changes.

Author: squidarth

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "truss"
-version = "0.7.13"
+version = "0.7.14rc2"
 description = "A seamless bridge from model development to model delivery"
 license = "MIT"
 readme = "README.md"

truss/cli/cli.py

@@ -258,14 +258,17 @@ def _extract_and_validate_model_identifier(
 
 
 def _extract_request_data(data: Optional[str], file: Optional[Path]):
-    if data is not None:
-        return json.loads(data)
-    elif file is not None:
-        return json.loads(Path(file).read_text())
-    else:
-        raise click.UsageError(
-            "You must provide exactly one of '--data (-d)' or '--file (-f)' options."
-        )
+    try:
+        if data is not None:
+            return json.loads(data)
+        if file is not None:
+            return json.loads(Path(file).read_text())
+    except json.JSONDecodeError:
+        raise click.UsageError("Request data must be valid json.")
+
+    raise click.UsageError(
+        "You must provide exactly one of '--data (-d)' or '--file (-f)' options."
+    )
 
 
 @truss_cli.command()

truss/remote/truss_remote.py

@@ -59,7 +59,7 @@ def _send_request(
         if method == "GET":
             response = requests.request(method, url, headers=headers, stream=stream)
         elif method == "POST":
-            if not data:
+            if data is None:
                 raise ValueError("POST request must have data")
             response = requests.request(
                 method, url, json=data, headers=headers, stream=stream

truss/templates/server/common/truss_server.py

@@ -132,7 +132,12 @@ async def predict(
         if self.is_binary(request):
             body = truss_msgpack_deserialize(body_raw)
         else:
-            body = json.loads(body_raw)
+            try:
+                body = json.loads(body_raw)
+            except json.JSONDecodeError as e:
+                raise HTTPException(
+                    status_code=400, detail=f"Invalid JSON payload: {str(e)}"
+                )
 
         # calls ModelWrapper.__call__, which runs validate, preprocess, predict, and postprocess
         response: Union[Dict, Generator] = await model(