Fix Gradio Streaming problems (#39)

* fix gradio streaming timeouts and langchain fix dependency

* fix formatting and add dev dependencies

* remove dep deps again

* ➕ add pre-commit to pyproject.toml

📝 update CONTRIBUTING

---------

Co-authored-by: Ajinkya Indulkar <26824103+ajndkr@users.noreply.github.com>

CONTRIBUTING.md

@@ -26,6 +26,5 @@ poetry install
 fastapi-async-langchain uses `pre-commit` to run code checks and tests before every commit. To install the pre-commit hooks, run the following commands:
 
 ```bash
-pip install pre-commit
 pre-commit install
 ```

fastapi_async_langchain/testing/gradio.py

@@ -12,12 +12,34 @@ def send_query(api_url: str, query: str, chat: list[Any], history: list[Any]):
     history.append(query)
 
     payload = {"query": query}
-    headers = {"accept": "text/event-stream", "Content-Type": "application/json"}
-    response = requests.post(api_url, headers=headers, json=payload, stream=True)
+    headers = {
+        "accept": "text/event-stream",
+        "Content-Type": "application/json",
+        "Connection": "keep-alive",
+    }
+
+    try:
+        response = requests.post(
+            api_url, headers=headers, json=payload, timeout=60, stream=True
+        )
+        response.raise_for_status()  # Raise stored HTTPError, if one occurred
+
+    except requests.exceptions.HTTPError as httpErr:
+        print(f"HTTP error occurred: {httpErr}")
+        return
+    except requests.exceptions.ConnectionError as connErr:
+        print(f"Error connecting: {connErr}")
+        return
+    except requests.exceptions.Timeout as timeOutErr:
+        print(f"Timeout error: {timeOutErr}")
+        return
+    except requests.exceptions.RequestException as reqErr:
+        print(f"Something went wrong with the request: {reqErr}")
+        return
 
     token_counter = 0
     partial_words = ""
-    for chunk in response.iter_content():
+    for chunk in response.iter_content(chunk_size=1024):  # Smaller chunk size
         if chunk:
             partial_words = partial_words + chunk.decode()
             if token_counter == 0:

pyproject.toml

@@ -12,10 +12,13 @@ packages = [{include = "fastapi_async_langchain"}]
 [tool.poetry.dependencies]
 python = "^3.9"
 fastapi = "^0.95.1"
-langchain = ">=0.0.166"
+langchain = ">=0.0.167"
 urllib3 = "<=1.26.15"  # added due to poetry errors
 python-dotenv = "^1.0.0"
 
+[tool.poetry.group.dev.dependencies]
+pre-commit = "^3.3.1"
+
 [build-system]
 requires = ["poetry-core"]
 build-backend = "poetry.core.masonry.api"