feat: add debug logging (#198)

README.md

@@ -564,6 +564,24 @@ options = StreamOptions(
 client.stream(fql('Product.all().eventSource()'), options)
 ```
 
+## Logging
+
+Logging is handled using Python's standard `logging` package under the `fauna` namespace. Logs include the HTTP request with body (excluding the `Authorization` header) and the full HTTP response.
+
+To enable logging:
+```python
+import logging
+from fauna.client import Client
+from fauna import fql
+
+logging.basicConfig(
+    level=logging.DEBUG
+)
+client = Client()
+client.query(fql('42'))
+```
+For configuration options or to set specific log levels, see Python's [Logging HOWTO](https://docs.python.org/3/howto/logging.html).
+
 ## Setup
 
 ```bash

fauna/client/client.py

@@ -1,3 +1,4 @@
+import logging
 from dataclasses import dataclass
 from datetime import timedelta
 from typing import Any, Dict, Iterator, Mapping, Optional, Union, List
@@ -13,6 +14,8 @@
 from fauna.http.http_client import HTTPClient
 from fauna.query import EventSource, Query, Page, fql
 
+logger = logging.getLogger("fauna")
+
 DefaultHttpConnectTimeout = timedelta(seconds=5)
 DefaultHttpReadTimeout: Optional[timedelta] = None
 DefaultHttpWriteTimeout = timedelta(seconds=5)
@@ -216,7 +219,7 @@ def __init__(
                     max_keepalive_connections=DefaultMaxIdleConnections,
                     keepalive_expiry=idle_timeout_s,
                 ),
-            ))
+            ), logger)
         fauna.global_http_client = c
 
       self._session = fauna.global_http_client

fauna/http/httpx_client.py

@@ -1,4 +1,5 @@
 import json
+import logging
 from contextlib import contextmanager
 from json import JSONDecodeError
 from typing import Mapping, Any, Optional, Iterator
@@ -50,9 +51,12 @@ def close(self) -> None:
 
 class HTTPXClient(HTTPClient):
 
-  def __init__(self, client: httpx.Client):
+  def __init__(self,
+               client: httpx.Client,
+               logger: logging.Logger = logging.getLogger("fauna")):
     super(HTTPXClient, self).__init__()
     self._c = client
+    self._logger = logger
 
   def request(
       self,
@@ -69,14 +73,29 @@ def request(
           json=data,
           headers=headers,
       )
+
+      if self._logger.isEnabledFor(logging.DEBUG):
+        headers_to_log = request.headers.copy()
+        headers_to_log.pop("Authorization")
+        self._logger.debug(
+            f"query.request method={request.method} url={request.url} headers={headers_to_log} data={data}"
+        )
+
     except httpx.InvalidURL as e:
       raise ClientError("Invalid URL Format") from e
 
     try:
-      return HTTPXResponse(self._c.send(
+      response = self._c.send(
           request,
           stream=False,
-      ))
+      )
+
+      if self._logger.isEnabledFor(logging.DEBUG):
+        self._logger.debug(
+            f"query.response status_code={response.status_code} headers={response.headers} data={response.text}"
+        )
+
+      return HTTPXResponse(response)
     except (httpx.HTTPError, httpx.InvalidURL) as e:
       raise NetworkError("Exception re-raised from HTTP request") from e
 
@@ -87,14 +106,37 @@ def stream(
       headers: Mapping[str, str],
       data: Mapping[str, Any],
   ) -> Iterator[Any]:
-    with self._c.stream(
-        "POST", url=url, headers=headers, json=data) as response:
+    request = self._c.build_request(
+        method="POST",
+        url=url,
+        headers=headers,
+        json=data,
+    )
+
+    if self._logger.isEnabledFor(logging.DEBUG):
+      headers_to_log = request.headers.copy()
+      headers_to_log.pop("Authorization")
+      self._logger.debug(
+          f"stream.request method={request.method} url={request.url} headers={headers_to_log} data={data}"
+      )
+
+    response = self._c.send(
+        request=request,
+        stream=True,
+    )
+
+    try:
       yield self._transform(response)
+    finally:
+      response.close()
 
   def _transform(self, response):
     try:
       for line in response.iter_lines():
-        yield json.loads(line)
+        loaded = json.loads(line)
+        if self._logger.isEnabledFor(logging.DEBUG):
+          self._logger.debug(f"stream.data data={loaded}")
+        yield loaded
     except httpx.ReadTimeout as e:
       raise NetworkError("Stream timeout") from e
     except (httpx.HTTPError, httpx.InvalidURL) as e:

tests/integration/test_stream.py

@@ -1,12 +1,11 @@
 import threading
-import time
 
 import httpx
 import pytest
 
 from fauna import fql
 from fauna.client import Client, StreamOptions
-from fauna.errors import ClientError, NetworkError, RetryableFaunaException, QueryRuntimeError
+from fauna.errors import ClientError, RetryableFaunaException, QueryRuntimeError, NetworkError
 from fauna.http.httpx_client import HTTPXClient
 
 
@@ -107,11 +106,16 @@ def test_max_retries(scoped_secret):
 
   count = [0]
 
-  def stream_func(*args, **kwargs):
+  old_send = httpx_client.send
+
+  def send_func(*args, **kwargs):
+    if not kwargs['stream']:
+      return old_send(*args, **kwargs)
+
     count[0] += 1
     raise NetworkError('foo')
 
-  httpx_client.stream = stream_func
+  httpx_client.send = send_func
 
   count[0] = 0
   with pytest.raises(RetryableFaunaException):