chore: import upstream snapshot with attribution

doc/source/serve/doc_code/image_classifier_example.py

@@ -0,0 +1,98 @@
+# __serve_example_begin__
+import requests
+import starlette
+
+from transformers import pipeline
+from io import BytesIO
+from PIL import Image
+
+from ray import serve
+from ray.serve.handle import DeploymentHandle
+
+
+@serve.deployment
+def downloader(image_url: str):
+    image_bytes = requests.get(image_url).content
+    image = Image.open(BytesIO(image_bytes)).convert("RGB")
+    return image
+
+
+@serve.deployment
+class ImageClassifier:
+    def __init__(self, downloader: DeploymentHandle):
+        self.downloader = downloader
+        self.model = pipeline(
+            "image-classification", model="google/vit-base-patch16-224"
+        )
+
+    async def classify(self, image_url: str) -> str:
+        image = await self.downloader.remote(image_url)
+        results = self.model(image)
+        return results[0]["label"]
+
+    async def __call__(self, req: starlette.requests.Request):
+        req = await req.json()
+        return await self.classify(req["image_url"])
+
+
+app = ImageClassifier.bind(downloader.bind())
+# __serve_example_end__
+
+
+@serve.deployment
+class ModifiedImageClassifier:
+    def __init__(self, downloader: DeploymentHandle):
+        self.downloader = downloader
+        self.model = pipeline(
+            "image-classification", model="google/vit-base-patch16-224"
+        )
+
+    async def classify(self, image_url: str) -> str:
+        image = await self.downloader.remote(image_url)
+        results = self.model(image)
+        return results[0]["label"]
+
+    # __serve_example_modified_begin__
+    async def __call__(self, req: starlette.requests.Request):
+        req = await req.json()
+        result = await self.classify(req["image_url"])
+
+        if req.get("should_translate") is True:
+            handle: DeploymentHandle = serve.get_app_handle("app2")
+            return await handle.translate.remote(result)
+
+        return result
+        # __serve_example_modified_end__
+
+
+serve.run(app, name="app1", route_prefix="/classify")
+# __request_begin__
+bear_url = "https://cdn.britannica.com/41/156441-050-A4424AEC/Grizzly-bear-Jasper-National-Park-Canada-Alberta.jpg"  # noqa
+resp = requests.post("http://localhost:8000/classify", json={"image_url": bear_url})
+
+print(resp.text)
+# 'brown bear, bruin, Ursus arctos'
+# __request_end__
+assert resp.text == "brown bear, bruin, Ursus arctos"
+
+from translator_example import app as translator_app  # noqa
+
+serve.run(
+    ModifiedImageClassifier.bind(downloader.bind()),
+    name="app1",
+    route_prefix="/classify",
+)
+serve.run(translator_app, name="app2")
+
+# __second_request_begin__
+bear_url = "https://cdn.britannica.com/41/156441-050-A4424AEC/Grizzly-bear-Jasper-National-Park-Canada-Alberta.jpg"  # noqa
+resp = requests.post(
+    "http://localhost:8000/classify",
+    json={"image_url": bear_url, "should_translate": True},
+)
+
+print(resp.text)
+# 'Braunbär, Bruin, Ursus arctos'
+# __second_request_end__
+
+assert resp.text == "Braunbär, Bruin, Ursus arctos"