fix(api): return structured error when image parameters are missing (fixes #76)

api/onnx_web/serve.py

@@ -13,7 +13,7 @@ from diffusers import (
     LMSDiscreteScheduler,
     PNDMScheduler,
 )
-from flask import Flask, jsonify, request, send_from_directory, url_for
+from flask import Flask, jsonify, make_response, request, send_from_directory, url_for
 from flask_cors import CORS
 from flask_executor import Executor
 from glob import glob
@@ -292,6 +292,20 @@ def get_model_path(model: str):
     return safer_join(context.model_path, model)
 
 
+def ready_reply(ready: bool):
+    return jsonify({
+        'ready': ready,
+    })
+
+
+def error_reply(err: str):
+    response = make_response(jsonify({
+        'error': err,
+    }))
+    response.status_code = 400
+    return response
+
+
 def serve_bundle_file(filename='index.html'):
     return send_from_directory(path.join('..', context.bundle_path), filename)
 
@@ -356,6 +370,9 @@ def list_schedulers():
 
 @app.route('/api/img2img', methods=['POST'])
 def img2img():
+    if 'source' not in request.files:
+        return error_reply('source image is required')
+
     source_file = request.files.get('source')
     source_image = Image.open(BytesIO(source_file.read())).convert('RGB')
 
@@ -410,6 +427,12 @@ def txt2img():
 
 @app.route('/api/inpaint', methods=['POST'])
 def inpaint():
+    if 'source' not in request.files:
+        return error_reply('source image is required')
+
+    if 'mask' not in request.files:
+        return error_reply('mask image is required')
+
     source_file = request.files.get('source')
     source_image = Image.open(BytesIO(source_file.read())).convert('RGB')
 
@@ -475,6 +498,9 @@ def inpaint():
 
 @app.route('/api/upscale', methods=['POST'])
 def upscale():
+    if 'source' not in request.files:
+        return error_reply('source image is required')
+
     source_file = request.files.get('source')
     source_image = Image.open(BytesIO(source_file.read())).convert('RGB')
 
@@ -507,15 +533,12 @@ def ready():
     if done is None:
         file = safer_join(context.output_path, output_file)
         if path.exists(file):
-            return jsonify({
-                'ready': True,
-            })
+            return ready_reply(True)
+
     elif done == True:
         executor.futures.pop(output_file)
 
-    return jsonify({
-        'ready': done,
-    })
+    return ready_reply(done)
 
 
 @app.route('/output/<path:filename>')