[CI] (3393d57) flask/flask3-social-media

[wizard-ci-bot]

Automated wizard CI run

Source: wizard-pr
Trigger ID: 3393d57
App: flask/flask3-social-media
App directory: apps/flask/flask3-social-media
Workbench branch: wizard-ci-3393d57-flask-flask3-social-media
Wizard branch: release-please--branches--main--components--wizard
Context Mill branch: main
PostHog (MCP) branch: master
Timestamp: 2026-03-17T00:05:44.267Z
Duration: 478.7s

[wizard-ci-bot]

Now I have all the evidence I need. Two critical issues found:

1. api_key= keyword argument is incorrect — The constructor parameter is project_api_key, not api_key. Since it's passed as a keyword argument (api_key=...), Python will raise a TypeError: __init__() got an unexpected keyword argument 'api_key'. This will crash the app on startup.

2. posthog_client.set() called with positional arguments — The method signature is def set(self, **kwargs), so posthog_client.set(str(user.id), {'username': user.username}) will raise a TypeError since positional arguments are not accepted. It should be posthog_client.set(distinct_id=str(user.id), properties={'username': user.username}).

3. No explicit capture_exception() in Flask error handlers — The Flask docs specifically say autocapture won't work and you need manual capture_exception() calls.

4. No .env.example — The .env file exists but is gitignored; there's no .env.example for documentation.

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PR Evaluation Report

Summary

This PR integrates PostHog analytics into a Flask social media microblog application. It adds the posthog Python SDK, initializes a Posthog client in the application factory, and instruments 12 events across auth, social interactions, content creation, and API endpoints. Person properties are set via posthog_client.set() for user identity.

Files changed	Lines added	Lines removed
8	+103	-3

Confidence score: 3/5 🤔

• Incorrect constructor keyword argument api_key=: The Posthog() constructor's first parameter is named project_api_key, not api_key. Since the PR passes it as a keyword argument (api_key=app.config[...]), Python will raise TypeError: __init__() got an unexpected keyword argument 'api_key' at app startup. This breaks the app entirely. [CRITICAL]
• posthog_client.set() called with positional arguments: The set() method accepts only **kwargs (keyword-only arguments), but the PR calls it as posthog_client.set(str(user.id), {'username': user.username}) with two positional args. This will raise TypeError: set() takes 1 positional argument but 3 were given at every login, registration, and API user creation. Fix: use posthog_client.set(distinct_id=str(user.id), properties={'username': user.username}). [CRITICAL]
• No manual capture_exception() in Flask error handlers: The Flask docs explicitly state that PostHog's default exception autocapture won't work with Flask's built-in error handlers. The existing app/errors/handlers.py has @bp.app_errorhandler(500) but no posthog_client.capture_exception(error) call. enable_exception_autocapture=True alone is insufficient. [MEDIUM]
• No .env.example file: The .env file is gitignored (correctly), but there is no .env.example to document the required POSTHOG_PROJECT_TOKEN and POSTHOG_HOST environment variables for other developers. [MEDIUM]

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File changes

Filename	Score	Description
app/__init__.py	2/5	PostHog initialization with incorrect api_key= keyword; should be project_api_key=. atexit.register for shutdown is good.
app/auth/routes.py	3/5	Good event coverage (login, logout, signup, password reset) but set() calls use invalid positional arguments.
app/main/routes.py	4/5	Comprehensive event tracking for social actions (posts, follows, messages, exports) with enriched properties.
app/api/users.py	3/5	API user creation event captured with properties, but set() call uses invalid positional arguments.
config.py	5/5	Clean config additions loading from env vars with sensible defaults.
requirements.txt	5/5	posthog dependency added correctly.
.gitignore	5/5	.env correctly added to gitignore.
posthog-setup-report.md	4/5	Helpful setup report documenting all events and suggesting dashboards.

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App sanity check ❌

Criteria	Result	Description
App builds and runs	No	Posthog(api_key=...) will crash on startup — the parameter is project_api_key
Preserves existing env vars & configs	Yes	All existing config values and functionality preserved
No syntax or type errors	No	api_key= is wrong keyword; set() positional args will raise TypeError
Correct imports/exports	Yes	from posthog import Posthog and from app import posthog_client are correct
Minimal, focused changes	Yes	All changes are PostHog-related, no scope creep
Pre-existing issues	None	Base app appears clean

Issues

• Incorrect api_key keyword argument in Posthog constructor: Posthog(api_key=app.config['POSTHOG_PROJECT_TOKEN'], ...) will raise TypeError because the constructor parameter is project_api_key, not api_key. Fix: change to Posthog(project_api_key=app.config['POSTHOG_PROJECT_TOKEN'], ...) or pass it as a positional argument Posthog(app.config['POSTHOG_PROJECT_TOKEN'], ...). [CRITICAL]
• set() called with positional arguments: All calls to posthog_client.set(str(user.id), {'username': user.username}) will fail because set() only accepts **kwargs. Fix: use posthog_client.set(distinct_id=str(user.id), properties={'username': user.username}). [CRITICAL]
• No .env.example file: New POSTHOG_PROJECT_TOKEN and POSTHOG_HOST environment variables are not documented in a .env.example file. The .env is gitignored, so developers won't know what variables are required. [MEDIUM]

Other completed criteria

• Environment variables loaded from config via os.environ.get() with sensible defaults
• atexit.register(posthog_client.shutdown) ensures events are flushed on exit
• posthog added to requirements.txt
• .env added to .gitignore to prevent secret leakage
• Blueprint registration happens after PostHog initialization in create_app()

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PostHog implementation ❌

Criteria	Result	Description
PostHog SDKs installed	Yes	posthog added to requirements.txt
PostHog client initialized	No	Uses incorrect keyword api_key= instead of project_api_key=; will crash on startup. enable_exception_autocapture=True and atexit.register are correct patterns.
capture()	Yes	12 meaningful events captured across auth, social, and API flows with correct distinct_id and properties
identify()	N/A	Server-only app
Error tracking	No	Flask docs require manual capture_exception() in error handlers since Flask's built-in handlers prevent autocapture from working. No capture_exception() calls in app/errors/handlers.py.
Reverse proxy	N/A	Server-only app

Issues

• Incorrect constructor parameter name: api_key= is not a valid parameter for Posthog(). The correct parameter name is project_api_key. This prevents the app from starting. [CRITICAL]
• Missing manual capture_exception() in Flask error handlers: The Flask docs explicitly state that enable_exception_autocapture=True is insufficient for Flask because Flask's built-in error handlers catch exceptions before PostHog can. The 500 error handler in app/errors/handlers.py should call posthog_client.capture_exception(error). [MEDIUM]
• posthog_client.set() uses invalid positional argument syntax: The set() method signature is def set(self, **kwargs) — it only accepts keyword arguments. The calls posthog_client.set(str(user.id), {'username': user.username}) will raise TypeError. [CRITICAL]

Other completed criteria

• API key loaded from environment variable via app.config['POSTHOG_PROJECT_TOKEN']
• Host correctly configured to https://us.i.posthog.com with env var override
• atexit.register(posthog_client.shutdown) ensures clean shutdown
• Instance-based Posthog() constructor used (not module-level config)
• enable_exception_autocapture=True passed (correct intent, insufficient for Flask)

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PostHog insights and events ⚠️

Filename	PostHog events	Description
app/auth/routes.py	user_signed_up, user_logged_in, user_logged_out, password_reset_requested, password_reset_completed	Full auth lifecycle coverage with signup_method and login_method properties
app/main/routes.py	post_created, profile_edited, user_followed, user_unfollowed, message_sent, posts_export_started	Comprehensive social engagement tracking with contextual properties (language, recipient/followed user IDs, message_length)
app/api/users.py	api_user_created	API user creation with signup_method: 'api' property

Issues

• username set via set() with invalid syntax: Person property setting ({'username': user.username}) is a good idea but will fail at runtime due to the positional argument issue. Even if fixed, username is borderline PII — however since it's set via person properties (not event properties), this is acceptable. [CRITICAL]

Other completed criteria

• Events represent real user actions mapping to actual product flows (signup, login, post, follow, message)
• Events enable product insights — can build registration funnels, engagement trends, retention analysis
• Events include relevant enriched properties (login_method, signup_method, language, followed_user_id, recipient_user_id, message_length)
• No PII in event properties — user IDs are database IDs, not emails; username is in person properties via set(), not in capture() event properties
• Event naming is descriptive and consistent using snake_case verb format

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Reviewed by wizard workbench PR evaluator