Enable flake8 lint validation (#20)

Author: seratch

.flake8

@@ -0,0 +1,5 @@
+[flake8]
+max-line-length = 125
+# E401: We are fine with multiple imports in a line
+# W503: This rule is not compatible with black (code formatter)
+ignore = E401,W503

.github/workflows/flake8.yml

@@ -0,0 +1,29 @@
+name: Lint validation using flake8
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    timeout-minutes: 5
+    strategy:
+      matrix:
+        python-version: ['3.9']
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v2
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Install dependencies
+      run: |
+        pip install -U pip
+        pip install -e ".[testing]"
+        # We manually upgrade it to make the builds stable
+        pip install "flake8==4.0.1"
+    - name: Run flake8
+      run: |
+        flake8 slack_discovery_sdk/

slack_discovery_sdk/client.py

@@ -154,7 +154,7 @@ def discovery_user_conversations(
                 "limit": limit,
             }
         )
-        if offset != None:
+        if offset is not None:
             kwargs.update({"offset": offset})
 
         return self.api_call(

slack_discovery_sdk/examples/utils.py

@@ -4,9 +4,9 @@
 
 FILE_EXTENSION = ".json"
 
-## This file contains functions which will help create a directory structure to organize and
-## hold the output from the discovery APIs. This is just meant as a helper to get you started,
-## and is by no means a production ready solution. Use this to get familiar with the discovery APIs.
+# This file contains functions which will help create a directory structure to organize and
+# hold the output from the discovery APIs. This is just meant as a helper to get you started,
+# and is by no means a production ready solution. Use this to get familiar with the discovery APIs.
 
 
 def export_json_to_file(
@@ -27,7 +27,7 @@ def export_json_to_file(
     Returns:
         None
     """
-    if channel_id != None:
+    if channel_id is not None:
         channel_folder = create_folder_for_channel(
             base_dir=base_dir,
             channel_id=channel_id,

slack_discovery_sdk/oauth.py

@@ -61,7 +61,7 @@ def do_GET(self):
                             body=self._build_html_page(main),
                             headers={"Content-Type": ["text/html; charset=utf-8"]},
                         )
-                    except Exception as _:
+                    except Exception:
                         _logger.exception("Failed to perform oauth.v2.access API call")
                         main = f"""
                         <p>Click <a href="{_install_path}">here</a> to install the app again.</p>

slack_discovery_sdk/response.py

@@ -43,7 +43,7 @@ class DiscoveryResponse:
     def __init__(  # type: ignore
         self,
         *,
-        client: "BaseDiscoveryClient",
+        client: "BaseDiscoveryClient",  # noqa: F821
         http_method: str,
         api_url: str,
         request_headers: dict,