Instrument Product Analytics
PostHogOfficialCreated by PostHog
- Skill
- Tool integration
- Data and AI
- MIT
- Low risk
AutoGineer summary
Written by AutoGineer from the skill’s own files, not by the author
This skill provides a structured, multi-step workflow to integrate PostHog product analytics into a wide variety of software projects. It guides the user through detecting the project's framework, installing the appropriate SDK, initializing the service, and strategically placing event capture calls. The skill emphasizes non-intrusive implementation, requiring that new analytics code be added alongside existing logic without altering the project's fundamental architecture. It also covers user identification, error tracking, and secure environment variable management.
What it does
- Detects the project's framework and language to determine the correct PostHog SDK.
- Handles initial SDK installation and initialization based on framework-specific patterns.
- Identifies key user actions and business-critical events for tracking.
- Implements event capture calls and user identification logic.
- Configures environment variables securely for API tokens and host URLs.
- Verifies the integration and performs targeted linting on modified files.
When to use it
- After implementing new features that require tracking for product analytics.
- When reviewing pull requests to ensure meaningful user behaviors are captured.
- During the initial setup of a new project that needs product analytics.
- When migrating or adding analytics to an existing application.
Advantages
- Supports a broad range of frontend, backend, and mobile frameworks.
- Ensures consistent event naming and property usage across the codebase.
- Prioritizes non-breaking changes and minimal impact on existing code structure.
- Automates the complex setup of environment variables and SDK initialization.
Usage examples
- “Add PostHog analytics to my Next.js project.”
- The agent will analyze the project structure, install the PostHog SDK, initialize it in the appropriate client/server files, and prompt you to identify key events to track.
- “I need to track user signups and errors in my Django backend.”
- The agent will locate your authentication logic, add identify calls, implement exception capture, and ensure the PostHog project tokens are managed via environment variables.
Install
Download the skill as a ZIP:
https://mp-staging.autogineer.com/agent-skills/posthog/instrument-product-analytics/downloadUnzip it into the cross-client skills folder of your project:
mkdir -p .agents/skills && unzip instrument-product-analytics.zip -d .agents/skills
Documentation by PostHog
Add PostHog product analytics events
Use this skill to add product analytics events (capture calls) that track meaningful user actions in new or changed code. Use it after implementing features or reviewing PRs to ensure key user behaviors are captured. If PostHog is not yet installed, this skill also covers initial SDK setup. Supports any framework or language.
Supported frameworks and languages: Next.js, React Router, Nuxt, Vue, TanStack Start, SvelteKit, Astro, Angular, Django, Flask, FastAPI, Laravel, PHP, Ruby on Rails, Go, Elixir, Android, iOS, Flutter, React Native, Expo, and more.
Instructions
Follow these steps IN ORDER:
STEP 1: Analyze the codebase and detect the platform.
Look for dependency files (package.json, pubspec.yaml, Podfile, Package.swift, requirements.txt, Gemfile, composer.json, go.mod, mix.exs, etc.) to determine the framework and language.
Look for lockfiles (pnpm-lock.yaml, package-lock.json, yarn.lock, bun.lockb, go.sum, pubspec.lock, Podfile.lock, Package.resolved, mix.lock) to determine the package manager.
Check for existing PostHog setup. If PostHog is already installed and initialized, skip to STEP 5.
STEP 2: Research integration. (Skip if PostHog is already set up.) 2.1. Find the reference file below that matches the detected framework — it is the source of truth for SDK initialization, provider setup, and event capture patterns. Read it now. 2.2. If no reference matches, fall back to your general knowledge and web search. Use posthog.com/docs as the primary search source.
STEP 3: Install the PostHog SDK. (Skip if PostHog is already set up.)
Add the PostHog SDK package for the detected platform. Do not manually edit package.json — use the package manager's install command.
STEP 4: Initialize PostHog. (Skip if PostHog is already set up.)
Follow the framework reference for where and how to initialize. This varies significantly by framework (e.g., instrumentation-client.ts for Next.js 15.3+, AppConfig.ready() for Django, create_app() for Flask).
STEP 5: Plan event tracking.
From the project's file list, select between 10 and 15 files that might have interesting business value for event tracking, especially conversion and churn events.
Also look for files related to login that could be used for identifying users, along with error handling.
Find any existing
posthog.capture()code. Make note of event name formatting. Don't duplicate existing events; supplement them.Track actions only, not pageviews (those can be captured automatically). Exceptions can be made for "viewed"-type events at the top of a conversion funnel.
Server-side events are REQUIRED if the project includes any instrumentable server-side code (API routes, server actions, webhook handlers, payment/checkout completion, authentication endpoints).
STEP 6: Implement event capture.
For each planned event, add
posthog.capture()calls with useful properties.If a file already has existing integration code for other tools or services, don't overwrite or remove that code. Place PostHog code below it.
Do not alter the fundamental architecture of existing files. Make additions minimal and targeted.
You must read a file immediately before attempting to write it.
STEP 7: Identify users.
Add PostHog
identify()calls on the client side during login and signup events. Use the contents of login and signup forms to identify users on submit.If both frontend and backend exist, pass the client-side session and distinct ID using
X-POSTHOG-DISTINCT-IDandX-POSTHOG-SESSION-IDheaders to the server-side code. On the server side, make sure events have a matching distinct ID.
STEP 8: Add error tracking.
Add PostHog exception capture error tracking to relevant files, particularly around critical user flows and API boundaries.
STEP 9: Set up environment variables.
Check if the project already has PostHog environment variables configured (e.g. in
.env,.env.local, or framework-specific env files). If valid values already exist, skip this step.If the PostHog project token is missing, use the PostHog MCP server's
projects-gettool to retrieve the project'sapi_token. If multiple projects are returned, ask the user which project to use. If the MCP server is not connected or not authenticated, ask the user for their PostHog project token instead.For the PostHog host URL: check the
projects-getMCP response for aregionfield —USmaps tohttps://us.i.posthog.com,EUmaps tohttps://eu.i.posthog.com. If the region is not available from the MCP response or from existing project configuration, ask the user: "Are you on PostHog US Cloud or EU Cloud?" Do not assume US Cloud.Write these values to the appropriate env file using the framework's naming convention.
Reference these environment variables in code instead of hardcoding them.
STEP 10: Verify and clean up.
Check the project for errors. Look for type checking or build scripts in package.json.
Ensure any components created were actually used.
Run any linter or prettier-like scripts found in the package.json, but ONLY on the files you have edited or created during this session. Never run formatting or linting across the entire project's codebase.
Reference files
references/EXAMPLE-next-app-router.md- next-app-router example project codereferences/EXAMPLE-next-pages-router.md- next-pages-router example project codereferences/EXAMPLE-react-react-router-6.md- react-react-router-6 example project codereferences/EXAMPLE-react-react-router-7-framework.md- react-react-router-7-framework example project codereferences/EXAMPLE-react-react-router-7-data.md- react-react-router-7-data example project codereferences/EXAMPLE-react-react-router-7-declarative.md- react-react-router-7-declarative example project codereferences/EXAMPLE-nuxt-3-6.md- nuxt-3-6 example project codereferences/EXAMPLE-nuxt-4.md- nuxt-4 example project codereferences/EXAMPLE-vue-3.md- vue-3 example project codereferences/EXAMPLE-react-tanstack-router-file-based.md- react-tanstack-router-file-based example project codereferences/EXAMPLE-react-tanstack-router-code-based.md- react-tanstack-router-code-based example project codereferences/EXAMPLE-tanstack-start.md- tanstack-start example project codereferences/EXAMPLE-sveltekit.md- sveltekit example project codereferences/EXAMPLE-astro-static.md- astro-static example project codereferences/EXAMPLE-astro-view-transitions.md- astro-view-transitions example project codereferences/EXAMPLE-astro-ssr.md- astro-ssr example project codereferences/EXAMPLE-astro-hybrid.md- astro-hybrid example project codereferences/EXAMPLE-angular.md- angular example project codereferences/EXAMPLE-django.md- django example project codereferences/EXAMPLE-flask.md- flask example project codereferences/EXAMPLE-fastapi.md- fastapi example project codereferences/EXAMPLE-python.md- python example project codereferences/EXAMPLE-laravel.md- laravel example project codereferences/EXAMPLE-php.md- php example project codereferences/EXAMPLE-ruby-on-rails.md- ruby-on-rails example project codereferences/EXAMPLE-ruby.md- ruby example project codereferences/EXAMPLE-android.md- android example project codereferences/EXAMPLE-swift.md- swift example project codereferences/EXAMPLE-react-native.md- react-native example project codereferences/EXAMPLE-expo.md- expo example project codereferences/next-js.md- Next.jsreferences/react-router-v6.md- React router v6references/react-router-v7-framework-mode.md- React router v7 framework mode (remix v3)references/react-router-v7-data-mode.md- React router v7 data modereferences/react-router-v7-declarative-mode.md- React router v7 declarative modereferences/nuxt-js-3-6.md- Nuxt.js (v3.0 to v3.6)references/nuxt-js.md- Nuxt.jsreferences/vue-js.md- Vue.jsreferences/tanstack-start.md- Tanstack startreferences/svelte.md- Sveltereferences/astro.md- Astroreferences/angular.md- Angularreferences/django.md- Djangoreferences/flask.md- Flaskreferences/python.md- Pythonreferences/posthog-python.md- PostHog python SDKreferences/dotnet.md- .netreferences/elixir.md- Elixirreferences/go.md- Goreferences/laravel.md- Laravelreferences/php.md- Phpreferences/ruby-on-rails.md- Ruby on railsreferences/ruby.md- Rubyreferences/android.md- Androidreferences/ios.md- Iosreferences/usage.md- Ios SDK usagereferences/configuration.md- Ios SDK configurationreferences/flutter.md- Flutterreferences/react-native.md- React nativereferences/identify-users.md- Identify usersreferences/COMMANDMENTS.md- Framework-specific rules the integration must follow
Each framework reference contains SDK-specific installation, initialization, and usage patterns. Find the one matching the user's stack.
Key principles
Environment variables: Always use environment variables for PostHog keys. Never hardcode them.
Minimal changes: Add PostHog code alongside existing integrations. Don't replace or restructure existing code.
Match the docs: Follow the framework reference's initialization and capture patterns exactly.
Files
- ATTRIBUTION.mdAdded by AutoGineer970 B
- LICENSELicence file added by AutoGineer1.0 KiB
- SKILL.md9.6 KiB
- references/COMMANDMENTS.md1.5 KiB
- references/EXAMPLE-android.md49.8 KiB
- references/EXAMPLE-angular.md23.1 KiB
- references/EXAMPLE-astro-hybrid.md27.5 KiB
- references/EXAMPLE-astro-ssr.md27.6 KiB
- references/EXAMPLE-astro-static.md19.6 KiB
- references/EXAMPLE-astro-view-transitions.md23.3 KiB
- references/EXAMPLE-django.md30.7 KiB
- references/EXAMPLE-expo.md35.1 KiB
- references/EXAMPLE-fastapi.md40.9 KiB
- references/EXAMPLE-flask.md32.4 KiB
- references/EXAMPLE-laravel.md59.3 KiB
- references/EXAMPLE-next-app-router.md17.6 KiB
- references/EXAMPLE-next-pages-router.md19.1 KiB
- references/EXAMPLE-nuxt-3-6.md22.3 KiB
- references/EXAMPLE-nuxt-4.md28.9 KiB
- references/EXAMPLE-php.md13.0 KiB
- references/EXAMPLE-python.md11.6 KiB
- references/EXAMPLE-react-native.md46.0 KiB
- references/EXAMPLE-react-react-router-6.md13.5 KiB
- references/EXAMPLE-react-react-router-7-data.md20.1 KiB
- references/EXAMPLE-react-react-router-7-declarative.md15.0 KiB
- references/EXAMPLE-react-react-router-7-framework.md32.5 KiB
- references/EXAMPLE-react-tanstack-router-code-based.md19.6 KiB
- references/EXAMPLE-react-tanstack-router-file-based.md18.3 KiB
- references/EXAMPLE-ruby-on-rails.md38.0 KiB
- references/EXAMPLE-ruby.md10.0 KiB
- references/EXAMPLE-sveltekit.md18.6 KiB
- references/EXAMPLE-swift.md18.8 KiB
- references/EXAMPLE-tanstack-start.md29.9 KiB
- references/EXAMPLE-vue-3.md17.9 KiB
- references/android.md33.3 KiB
- references/angular.md16.5 KiB
- references/astro.md15.8 KiB
- references/configuration.md17.2 KiB
- references/django.md14.9 KiB
- references/dotnet.md25.8 KiB
- references/elixir.md17.6 KiB
- references/flask.md8.1 KiB
- references/flutter.md42.8 KiB
- references/go.md20.1 KiB
- references/identify-users.md12.2 KiB
- references/ios.md8.0 KiB
- references/laravel.md13.1 KiB
- references/next-js.md18.3 KiB
- references/nuxt-js-3-6.md11.4 KiB
- references/nuxt-js.md15.1 KiB
- references/php.md23.7 KiB
- references/posthog-python.md69.3 KiB
- references/python.md52.2 KiB
- references/react-native.md59.9 KiB
- references/react-router-v6.md13.6 KiB
- references/react-router-v7-data-mode.md13.5 KiB
- references/react-router-v7-declarative-mode.md13.7 KiB
- references/react-router-v7-framework-mode.md20.2 KiB
- references/ruby-on-rails.md19.7 KiB
- references/ruby.md25.5 KiB
- references/svelte.md14.6 KiB
- references/tanstack-start.md12.8 KiB
- references/usage.md29.2 KiB
- references/vue-js.md13.4 KiB
references/EXAMPLE-fastapi.md
PostHog fastapi Example Project
Repository: https://github.com/PostHog/context-mill Path: example-apps/fastapi
README.md
PostHog FastAPI Example
A FastAPI application demonstrating PostHog integration for analytics, feature flags, and error tracking.
Features
User registration and authentication with cookie-based sessions
SQLite database persistence with SQLAlchemy
User identification and property tracking
Custom event tracking
Feature flags with payload support
Error tracking with manual exception capture
Quick Start
Create and activate a virtual environment:
python -m venv venv source venv/bin/activate # On Windows: venv\Scripts\activateInstall dependencies:
pip install -r requirements.txtCopy the environment file and configure:
cp .env.example .env # Edit .env with your PostHog project keyRun the application:
python run.pyOpen http://localhost:5002 and either:
Login with default credentials:
[email protected]/adminOr click "Sign up here" to create a new account
PostHog Integration Points
User Registration
New users are identified and tracked on signup using the context-based API:
with new_context():
identify_context(user.email)
tag('email', user.email)
tag('is_staff', user.is_staff)
capture('user_signed_up', properties={'signup_method': 'form'})User Identification
Users are identified on login with their properties:
with new_context():
identify_context(user.email)
tag('email', user.email)
tag('is_staff', user.is_staff)
capture('user_logged_in', properties={'login_method': 'password'})Event Tracking
Custom events are captured throughout the app:
with new_context():
identify_context(current_user.email)
capture('burrito_considered', properties={'total_considerations': count})Feature Flags
The dashboard demonstrates feature flag checking:
show_new_feature = posthog.feature_enabled(
'new-dashboard-feature',
current_user.email,
person_properties={'email': current_user.email, 'is_staff': current_user.is_staff}
)
feature_config = posthog.get_feature_flag_payload('new-dashboard-feature', current_user.email)Error Tracking
The example demonstrates two approaches to error tracking:
Manual capture for specific critical operations** (app/routers/api.py).
try:
# Critical operation that might fail
result = process_payment()
except Exception as e:
# Manually capture this specific exception
with new_context():
identify_context(current_user.email)
event_id = posthog.capture_exception(e)
return JSONResponse({
"error": "Operation failed",
"error_id": event_id,
"message": f"Error captured in PostHog. Reference ID: {event_id}"
}, status_code=500)The /api/test-error endpoint demonstrates manual exception capture. Use ?capture=true to capture in PostHog, or ?capture=false to skip tracking.
Project Structure
example-apps/fastapi/
├── app/
│ ├── __init__.py # Package marker
│ ├── config.py # Pydantic Settings configuration
│ ├── database.py # SQLAlchemy setup
│ ├── dependencies.py # FastAPI dependency injection
│ ├── main.py # Application factory and lifespan
│ ├── models.py # User model (SQLAlchemy)
│ ├── routers/
│ │ ├── __init__.py # Routers package
│ │ ├── main.py # Page routes (HTML)
│ │ └── api.py # API endpoints (JSON)
│ └── templates/ # Jinja2 templates
├── .env.example
├── .gitignore
├── requirements.txt
├── README.md
└── run.py # Entry point (uvicorn).env.example
POSTHOG_PROJECT_TOKEN=<ph_project_token>
POSTHOG_HOST=https://us.i.posthog.com
SECRET_KEY=your-secret-key-here
DEBUG=True
POSTHOG_DISABLED=False
app/init.py
"""FastAPI PostHog example application."""
app/config.py
"""FastAPI application configuration using Pydantic Settings."""
from functools import lru_cache
from pydantic_settings import BaseSettings, SettingsConfigDict
class Settings(BaseSettings):
"""Application settings loaded from environment variables."""
model_config = SettingsConfigDict(
env_file=".env",
env_file_encoding="utf-8",
extra="ignore",
)
# Application
secret_key: str = "dev-secret-key-change-in-production"
debug: bool = True
# Database (SQLite like Flask example)
database_url: str = "sqlite:///./db.sqlite3"
# PostHog
posthog_project_token: str = "<ph_project_token>"
posthog_host: str = "https://us.i.posthog.com"
posthog_disabled: bool = False
@lru_cache
def get_settings() -> Settings:
"""Get cached settings instance."""
return Settings()
app/database.py
"""Database configuration with SQLAlchemy."""
from sqlalchemy import create_engine
from sqlalchemy.orm import DeclarativeBase, sessionmaker
from app.config import get_settings
settings = get_settings()
engine = create_engine(
settings.database_url,
connect_args={"check_same_thread": False}, # Required for SQLite
)
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
class Base(DeclarativeBase):
"""Base class for SQLAlchemy models."""
pass
def get_db():
"""Dependency that provides a database session."""
db = SessionLocal()
try:
yield db
finally:
db.close()
def init_db():
"""Create all database tables."""
Base.metadata.create_all(bind=engine)
app/dependencies.py
"""Authentication dependencies for FastAPI."""
from typing import Annotated, Optional
from fastapi import Cookie, Depends, HTTPException, status
from itsdangerous import BadSignature, URLSafeSerializer
from sqlalchemy.orm import Session
from app.config import get_settings
from app.database import get_db
from app.models import User
settings = get_settings()
serializer = URLSafeSerializer(settings.secret_key)
def get_session_user_id(session_token: Annotated[Optional[str], Cookie()] = None) -> Optional[int]:
"""Extract user ID from session cookie."""
if not session_token:
return None
try:
data = serializer.loads(session_token)
return data.get("user_id")
except BadSignature:
return None
def get_current_user(
db: Annotated[Session, Depends(get_db)],
user_id: Annotated[Optional[int], Depends(get_session_user_id)],
) -> Optional[User]:
"""Get the current authenticated user, or None if not authenticated."""
if user_id is None:
return None
return User.get_by_id(db, user_id)
def require_auth(
current_user: Annotated[Optional[User], Depends(get_current_user)],
) -> User:
"""Require authentication - raises 401 if not authenticated."""
if current_user is None:
raise HTTPException(
status_code=status.HTTP_401_UNAUTHORIZED,
detail="Authentication required",
)
return current_user
def create_session_token(user_id: int) -> str:
"""Create a signed session token for the user."""
return serializer.dumps({"user_id": user_id})
# Type aliases for cleaner dependency injection
CurrentUser = Annotated[Optional[User], Depends(get_current_user)]
RequiredUser = Annotated[User, Depends(require_auth)]
DbSession = Annotated[Session, Depends(get_db)]
app/main.py
"""FastAPI application with PostHog integration."""
from contextlib import asynccontextmanager
from pathlib import Path
import posthog
from fastapi import FastAPI, Request
from fastapi.responses import HTMLResponse, JSONResponse
from fastapi.staticfiles import StaticFiles
from fastapi.templating import Jinja2Templates
from app.config import get_settings
from app.database import SessionLocal, init_db
from app.middleware import PostHogMiddleware
from app.models import User
from app.routers import api, main
settings = get_settings()
# Setup templates
templates_dir = Path(__file__).parent / "templates"
templates = Jinja2Templates(directory=str(templates_dir))
@asynccontextmanager
async def lifespan(app: FastAPI):
"""Application lifespan events for startup/shutdown."""
# Startup: Initialize PostHog
if not settings.posthog_disabled:
posthog.api_key = settings.posthog_project_token
posthog.host = settings.posthog_host
posthog.debug = settings.debug
# Initialize database and seed default user
init_db()
db = SessionLocal()
try:
if not User.get_by_email(db, "[email protected]"):
User.create_user(
db,
email="[email protected]",
password="admin",
is_staff=True,
)
finally:
db.close()
yield
# Shutdown: Flush PostHog events
if not settings.posthog_disabled:
posthog.flush()
app = FastAPI(
title="PostHog FastAPI Example",
description="Example application demonstrating PostHog integration with FastAPI",
lifespan=lifespan,
)
app.add_middleware(PostHogMiddleware)
# Include routers
app.include_router(main.router)
app.include_router(api.router, prefix="/api")
# Error handlers
@app.exception_handler(404)
async def not_found_handler(request: Request, exc):
"""Handle 404 errors."""
if request.url.path.startswith("/api/"):
return JSONResponse({"error": "Not found"}, status_code=404)
return templates.TemplateResponse(
request, "errors/404.html", status_code=404
)
@app.exception_handler(500)
async def internal_error_handler(request: Request, exc):
"""Handle 500 errors."""
if request.url.path.startswith("/api/"):
return JSONResponse({"error": "Internal server error"}, status_code=500)
return templates.TemplateResponse(
request, "errors/500.html", status_code=500
)
app/middleware.py
"""PostHog middleware for automatic context and user identification.
Uses pure ASGI middleware instead of BaseHTTPMiddleware for better performance/best practices.
"""
from http.cookies import SimpleCookie
from typing import Callable, Optional
from posthog import identify_context, new_context, tag
from app.config import get_settings
from app.database import SessionLocal
from app.dependencies import serializer
from app.models import User
class PostHogMiddleware:
"""Pure ASGI middleware that wraps each request in a PostHog context.
If the user is authenticated, identifies them in the context so routes
can just call capture() without needing to set up context each time.
Uses pure ASGI interface for better performance than BaseHTTPMiddleware.
"""
def __init__(self, app):
self.app = app
self.settings = get_settings()
async def __call__(self, scope, receive, send):
if scope["type"] != "http" or self.settings.posthog_disabled:
await self.app(scope, receive, send)
return
user = self._get_user_from_scope(scope)
with new_context():
if user:
identify_context(str(user.id))
tag("is_staff", user.is_staff)
await self.app(scope, receive, send)
def _get_user_from_scope(self, scope) -> Optional[User]:
"""Extract authenticated user from session cookie in ASGI scope."""
headers = dict(scope.get("headers", []))
cookie_header = headers.get(b"cookie", b"").decode("utf-8")
if not cookie_header:
return None
cookies = SimpleCookie()
cookies.load(cookie_header)
session_cookie = cookies.get("session_token")
if not session_cookie:
return None
session_token = session_cookie.value
try:
data = serializer.loads(session_token)
user_id = data.get("user_id")
except Exception:
return None
if not user_id:
return None
db = SessionLocal()
try:
return User.get_by_id(db, user_id)
finally:
db.close()
app/models.py
"""User model with SQLite persistence (similar to Flask example)."""
from datetime import datetime, timezone
from typing import Optional
from sqlalchemy import Boolean, DateTime, Integer, String
from sqlalchemy.orm import Mapped, Session, mapped_column
from werkzeug.security import check_password_hash, generate_password_hash
from app.database import Base
class User(Base):
"""User model with SQLite persistence."""
__tablename__ = "users"
id: Mapped[int] = mapped_column(Integer, primary_key=True)
email: Mapped[str] = mapped_column(String(254), unique=True, nullable=False)
password_hash: Mapped[str] = mapped_column(String(256), nullable=False)
name: Mapped[Optional[str]] = mapped_column(String(100), nullable=True)
is_staff: Mapped[bool] = mapped_column(Boolean, default=False)
is_active: Mapped[bool] = mapped_column(Boolean, default=True)
login_count: Mapped[int] = mapped_column(Integer, default=0)
date_joined: Mapped[datetime] = mapped_column(
DateTime, default=lambda: datetime.now(timezone.utc)
)
def set_password(self, password: str) -> None:
"""Hash and set the user's password."""
self.password_hash = generate_password_hash(password, method="pbkdf2:sha256")
def check_password(self, password: str) -> bool:
"""Verify the password against the hash."""
return check_password_hash(self.password_hash, password)
@classmethod
def create_user(
cls, db: Session, email: str, password: str, is_staff: bool = False
) -> "User":
"""Create and save a new user."""
user = cls(email=email, is_staff=is_staff)
# nosemgrep: python.django.security.audit.unvalidated-password.unvalidated-password
user.set_password(password)
db.add(user)
db.commit()
db.refresh(user)
return user
@classmethod
def get_by_id(cls, db: Session, user_id: int) -> Optional["User"]:
"""Get user by ID."""
return db.query(cls).filter(cls.id == user_id).first()
@classmethod
def get_by_email(cls, db: Session, email: str) -> Optional["User"]:
"""Get user by email."""
return db.query(cls).filter(cls.email == email).first()
@classmethod
def authenticate(cls, db: Session, email: str, password: str) -> Optional["User"]:
"""Authenticate user with email and password."""
user = cls.get_by_email(db, email)
if user and user.check_password(password):
return user
return None
def record_login(self, db: Session) -> bool:
"""Record a login and return whether this is the user's first login."""
is_first_login = self.login_count == 0
self.login_count += 1
db.commit()
return is_first_login
def update_profile(self, db: Session, name: Optional[str] = None) -> list:
"""Update user profile and return list of changed fields."""
changed_fields = []
if name is not None and name != self.name:
self.name = name
changed_fields.append("name")
if changed_fields:
db.commit()
return changed_fields
def __repr__(self) -> str:
return f"<User {self.email}>"
app/routers/init.py
"""FastAPI routers package."""
app/routers/api.py
"""API endpoints demonstrating PostHog integration patterns."""
from typing import Annotated
import posthog
from fastapi import APIRouter, Cookie, Form, Query
from fastapi.responses import JSONResponse
from posthog import capture
from app.dependencies import RequiredUser
router = APIRouter()
MAX_BURRITO_COUNT = 10000
@router.post("/burrito/consider")
async def consider_burrito(
current_user: RequiredUser,
burrito_count: Annotated[int, Cookie()] = 0,
):
"""Track burrito consideration event."""
safe_count = max(0, min(burrito_count, MAX_BURRITO_COUNT))
new_count = safe_count + 1
capture("burrito_considered", properties={"total_considerations": new_count})
response = JSONResponse({"success": True, "count": new_count})
response.set_cookie(
key="burrito_count",
value=str(new_count),
httponly=True,
samesite="lax",
)
return response
@router.post("/test-error")
async def test_error(
current_user: RequiredUser,
capture_param: Annotated[str, Query(alias="capture")] = "true",
):
"""Test endpoint demonstrating manual exception capture in PostHog."""
should_capture = capture_param.lower() == "true"
try:
raise Exception("Test exception from critical operation")
except Exception as e:
if should_capture:
event_id = posthog.capture_exception(e)
return JSONResponse(
{
"error": "Operation failed",
"error_id": event_id,
"message": f"Error captured in PostHog. Reference ID: {event_id}",
},
status_code=500,
)
else:
return JSONResponse({"error": "Operation failed"}, status_code=500)
@router.post("/trigger-error")
async def trigger_error(
current_user: RequiredUser,
error_type: Annotated[str, Form()] = "generic",
):
"""Trigger different error types for testing error tracking."""
error_messages = {
"value": "Invalid value provided",
"key": "Missing required key",
"generic": "Generic test error",
}
safe_error_type = error_type if error_type in error_messages else "generic"
error_message = error_messages[safe_error_type]
try:
if safe_error_type == "value":
raise ValueError(error_message)
elif safe_error_type == "key":
raise KeyError("missing_key")
else:
raise Exception(error_message)
except Exception as e:
posthog.capture_exception(e)
capture(
"error_triggered",
properties={"error_type": safe_error_type, "error_message": error_message},
)
return JSONResponse(
{
"success": True,
"message": "Error captured in PostHog",
"error": error_message,
}
)
@router.post("/reports/activity")
async def generate_activity_report(
current_user: RequiredUser,
report_type: Annotated[str, Form()] = "summary",
):
"""Generate user activity report."""
valid_report_types = {"summary", "detailed", "export"}
safe_report_type = report_type if report_type in valid_report_types else "summary"
report_data = {
"user": current_user.email,
"name": current_user.name,
"date_joined": current_user.date_joined.isoformat(),
"login_count": current_user.login_count,
"is_staff": current_user.is_staff,
}
if safe_report_type == "detailed":
report_data["account_age_days"] = (
__import__("datetime").datetime.now(__import__("datetime").timezone.utc)
- current_user.date_joined
).days
row_count = len(report_data)
capture(
"report_generated",
properties={
"report_type": safe_report_type,
"row_count": row_count,
"username": current_user.email,
},
)
return JSONResponse(
{
"success": True,
"report_type": safe_report_type,
"row_count": row_count,
"data": report_data,
}
)
app/routers/main.py
"""Main routes demonstrating PostHog integration patterns."""
from pathlib import Path
from typing import Annotated
import posthog
from fastapi import APIRouter, Cookie, Depends, Form, Request
from fastapi.responses import HTMLResponse, RedirectResponse
from fastapi.templating import Jinja2Templates
from posthog import capture, identify_context, new_context
from app.dependencies import (
CurrentUser,
DbSession,
RequiredUser,
create_session_token,
)
from app.models import User
router = APIRouter()
# Setup templates
templates_dir = Path(__file__).parent.parent / "templates"
templates = Jinja2Templates(directory=str(templates_dir))
@router.get("/", response_class=HTMLResponse)
async def home(request: Request, current_user: CurrentUser, db: DbSession):
"""Home/login page."""
if current_user:
return RedirectResponse(url="/dashboard", status_code=302)
return templates.TemplateResponse(
request, "home.html", {"current_user": current_user}
)
@router.post("/", response_class=HTMLResponse)
async def login(
request: Request,
db: DbSession,
email: Annotated[str, Form()],
password: Annotated[str, Form()],
):
"""Handle login form submission."""
user = User.authenticate(db, email, password)
if user:
is_new_user = user.record_login(db)
with new_context():
identify_context(str(user.id))
capture(
"user_logged_in",
properties={
"$set": {"email": user.email, "is_staff": user.is_staff},
"is_new_user": is_new_user,
},
)
# Create session and redirect
response = RedirectResponse(url="/dashboard", status_code=302)
response.set_cookie(
key="session_token",
value=create_session_token(user.id),
httponly=True,
samesite="lax",
)
return response
# Login failed
return templates.TemplateResponse(
request,
"home.html",
{"current_user": None, "error": "Invalid email or password"},
)
@router.get("/signup", response_class=HTMLResponse)
async def signup_page(request: Request, current_user: CurrentUser):
"""User registration page."""
if current_user:
return RedirectResponse(url="/dashboard", status_code=302)
return templates.TemplateResponse(
request, "signup.html", {"current_user": current_user}
)
@router.post("/signup", response_class=HTMLResponse)
async def signup(
request: Request,
db: DbSession,
email: Annotated[str, Form()],
password: Annotated[str, Form()],
password_confirm: Annotated[str, Form()],
):
"""Handle signup form submission."""
error = None
if not email or not password:
error = "Email and password are required"
elif password != password_confirm:
error = "Passwords do not match"
elif User.get_by_email(db, email):
error = "Email already registered"
if error:
return templates.TemplateResponse(
request, "signup.html", {"current_user": None, "error": error}
)
# Create new user
user = User.create_user(db, email=email, password=password, is_staff=False)
with new_context():
identify_context(str(user.id))
capture(
"user_signed_up",
properties={
"$set": {"email": user.email, "is_staff": user.is_staff},
"signup_method": "form",
},
)
# Create session and redirect
response = RedirectResponse(url="/dashboard", status_code=302)
response.set_cookie(
key="session_token",
value=create_session_token(user.id),
httponly=True,
samesite="lax",
)
return response
@router.get("/logout")
async def logout(current_user: RequiredUser):
"""Logout and capture event."""
capture("user_logged_out")
response = RedirectResponse(url="/", status_code=302)
response.delete_cookie(key="session_token")
return response
@router.get("/dashboard", response_class=HTMLResponse)
async def dashboard(
request: Request,
current_user: RequiredUser,
):
"""Dashboard with feature flag demonstration."""
capture("dashboard_viewed", properties={"is_staff": current_user.is_staff})
# Check feature flag
show_new_feature = posthog.feature_enabled(
"new-dashboard-feature",
current_user.email,
person_properties={
"email": current_user.email,
"is_staff": current_user.is_staff,
},
)
# Get feature flag payload
feature_config = posthog.get_feature_flag_payload(
"new-dashboard-feature", current_user.email
)
return templates.TemplateResponse(
request,
"dashboard.html",
{
"current_user": current_user,
"show_new_feature": show_new_feature,
"feature_config": feature_config,
},
)
@router.get("/burrito", response_class=HTMLResponse)
async def burrito(
request: Request,
current_user: RequiredUser,
burrito_count: Annotated[int, Cookie()] = 0,
):
"""Burrito consideration tracker page."""
return templates.TemplateResponse(
request,
"burrito.html",
{"current_user": current_user, "burrito_count": burrito_count},
)
@router.get("/profile", response_class=HTMLResponse)
async def profile(request: Request, current_user: RequiredUser):
"""User profile page."""
capture("profile_viewed")
return templates.TemplateResponse(
request, "profile.html", {"current_user": current_user}
)
@router.post("/profile", response_class=HTMLResponse)
async def update_profile(
request: Request,
db: DbSession,
current_user: RequiredUser,
name: Annotated[str, Form()],
):
"""Handle profile update."""
fields_changed = current_user.update_profile(db, name=name)
if fields_changed:
capture(
"profile_updated",
properties={
"username": current_user.email,
"fields_changed": fields_changed,
},
)
return templates.TemplateResponse(
request,
"profile.html",
{
"current_user": current_user,
"success": "Profile updated" if fields_changed else None,
},
)
app/templates/base.html
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>{% block title %}PostHog FastAPI Example{% endblock %}</title>
<style>
* {
box-sizing: border-box;
margin: 0;
padding: 0;
}
body {
font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
line-height: 1.6;
background-color: #f5f5f5;
color: #333;
}
.container {
max-width: 800px;
margin: 0 auto;
padding: 20px;
}
nav {
background: #1d4ed8;
padding: 15px 20px;
margin-bottom: 30px;
}
nav a {
color: white;
text-decoration: none;
margin-right: 20px;
}
nav a:hover {
text-decoration: underline;
}
.card {
background: white;
border-radius: 8px;
padding: 20px;
margin-bottom: 20px;
box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}
h1, h2, h3 {
margin-bottom: 15px;
color: #1d4ed8;
}
button, .btn {
background: #1d4ed8;
color: white;
border: none;
padding: 10px 20px;
border-radius: 5px;
cursor: pointer;
font-size: 14px;
display: inline-block;
text-decoration: none;
}
button:hover, .btn:hover {
background: #1e40af;
}
button.danger {
background: #dc2626;
}
button.danger:hover {
background: #b91c1c;
}
input {
width: 100%;
padding: 10px;
margin-bottom: 15px;
border: 1px solid #ddd;
border-radius: 5px;
font-size: 14px;
}
.messages {
margin-bottom: 20px;
}
.message {
padding: 10px 15px;
border-radius: 5px;
margin-bottom: 10px;
}
.message.error {
background: #fee2e2;
color: #dc2626;
}
.message.success {
background: #d1fae5;
color: #059669;
}
.feature-flag {
background: #fef3c7;
border: 2px dashed #f59e0b;
padding: 15px;
border-radius: 8px;
margin: 20px 0;
}
code {
background: #f3f4f6;
padding: 2px 6px;
border-radius: 3px;
font-family: monospace;
}
pre {
background: #1e293b;
color: #e2e8f0;
padding: 16px;
border-radius: 8px;
overflow-x: auto;
font-size: 13px;
}
.count {
font-size: 48px;
font-weight: bold;
color: #1d4ed8;
text-align: center;
padding: 20px;
}
table {
width: 100%;
border-collapse: collapse;
margin: 16px 0;
}
th, td {
padding: 12px;
text-align: left;
border-bottom: 1px solid #eee;
}
th {
background: #f8fafc;
font-weight: 600;
}
</style>
</head>
<body>
{% if current_user %}
<nav>
<a href="/dashboard">Dashboard</a>
<a href="/burrito">Burrito</a>
<a href="/profile">Profile</a>
<a href="/logout" style="float: right;">Logout ({{ current_user.email }})</a>
</nav>
{% endif %}
<div class="container">
{% if error %}
<div class="messages">
<div class="message error">{{ error }}</div>
</div>
{% endif %}
{% if success %}
<div class="messages">
<div class="message success">{{ success }}</div>
</div>
{% endif %}
{% block content %}{% endblock %}
</div>
{% block scripts %}{% endblock %}
</body>
</html>
app/templates/burrito.html
{% extends "base.html" %}
{% block title %}Burrito - PostHog FastAPI Example{% endblock %}
{% block content %}
<div class="card">
<h1>Burrito Consideration Tracker</h1>
<p>This page demonstrates custom event tracking with PostHog.</p>
<div class="count" id="burrito-count">{{ burrito_count }}</div>
<p style="text-align: center; color: #666;">Times you've considered a burrito</p>
<div style="text-align: center; margin-top: 20px;">
<button onclick="considerBurrito()">Consider a Burrito</button>
</div>
</div>
<div class="card">
<h3>Code Example</h3>
<pre>
# API endpoint captures the event
with new_context():
identify_context(current_user.email)
capture('burrito_considered', properties={
'total_considerations': burrito_count
})</pre>
</div>
{% endblock %}
{% block scripts %}
<script>
async function considerBurrito() {
try {
const response = await fetch('/api/burrito/consider', {
method: 'POST',
headers: {
'Content-Type': 'application/json'
}
});
const data = await response.json();
if (data.success) {
document.getElementById('burrito-count').textContent = data.count;
}
} catch (error) {
console.error('Error:', error);
}
}
</script>
{% endblock %}
app/templates/dashboard.html
{% extends "base.html" %}
{% block title %}Dashboard - PostHog FastAPI Example{% endblock %}
{% block content %}
<div class="card">
<h1>Dashboard</h1>
<p>Welcome back, {{ current_user.email }}!</p>
</div>
<div class="card">
<h2>Feature Flags</h2>
{% if show_new_feature %}
<div class="feature-flag">
<strong>New Feature Enabled!</strong>
<p>You're seeing this because the <code>new-dashboard-feature</code> flag is enabled for you.</p>
{% if feature_config %}
<p><strong>Feature Configuration:</strong></p>
<pre>{{ feature_config | tojson(indent=2) }}</pre>
{% endif %}
</div>
{% else %}
<p>The <code>new-dashboard-feature</code> flag is not enabled for your account.</p>
{% endif %}
<h3 style="margin-top: 20px;">Code Example</h3>
<pre>
# Check if feature flag is enabled
show_new_feature = posthog.feature_enabled(
'new-dashboard-feature',
user_id,
person_properties={
'email': current_user.email,
'is_staff': current_user.is_staff
}
)
# Get feature flag payload
feature_config = posthog.get_feature_flag_payload(
'new-dashboard-feature',
user_id
)</pre>
</div>
{% endblock %}
app/templates/errors/404.html
{% extends "base.html" %}
{% block title %}Page Not Found - PostHog FastAPI Example{% endblock %}
{% block content %}
<div class="card">
<h1>404 - Page Not Found</h1>
<p>The page you're looking for doesn't exist.</p>
<a href="/" class="btn">Go Home</a>
</div>
{% endblock %}
app/templates/errors/500.html
{% extends "base.html" %}
{% block title %}Server Error - PostHog FastAPI Example{% endblock %}
{% block content %}
<div class="card">
<h1>500 - Internal Server Error</h1>
<p>Something went wrong on our end. Please try again later.</p>
<a href="/" class="btn">Go Home</a>
</div>
{% endblock %}
app/templates/home.html
{% extends "base.html" %}
{% block title %}Login - PostHog FastAPI Example{% endblock %}
{% block content %}
<div class="card">
<h1>Welcome to PostHog FastAPI Example</h1>
<p>This example demonstrates how to integrate PostHog with a FastAPI application.</p>
<form method="POST">
<label for="email">Email</label>
<input type="email" id="email" name="email" required>
<label for="password">Password</label>
<input type="password" id="password" name="password" required>
<button type="submit">Login</button>
</form>
<p style="margin-top: 16px; font-size: 14px; color: #666;">
Don't have an account? <a href="/signup">Sign up here</a>
</p>
<p style="font-size: 14px; color: #666;">
<strong>Tip:</strong> Default credentials are [email protected]/admin
</p>
</div>
<div class="card">
<h2>Features Demonstrated</h2>
<ul style="margin-left: 20px; color: #666;">
<li>User registration and identification</li>
<li>Event tracking</li>
<li>Feature flags</li>
<li>Error tracking</li>
<li>Group analytics</li>
</ul>
</div>
{% endblock %}
app/templates/profile.html
{% extends "base.html" %}
{% block title %}Profile - PostHog FastAPI Example{% endblock %}
{% block content %}
<div class="card">
<h1>Your Profile</h1>
<p>This page demonstrates profile updates and report generation with PostHog.</p>
{% if success %}
<div class="message success">{{ success }}</div>
{% endif %}
<form method="POST" action="/profile">
<table>
<tr>
<th>Email</th>
<td>{{ current_user.email }}</td>
</tr>
<tr>
<th>Name</th>
<td>
<input type="text" name="name" value="{{ current_user.name or '' }}" placeholder="Enter your name">
</td>
</tr>
<tr>
<th>Date Joined</th>
<td>{{ current_user.date_joined.strftime('%Y-%m-%d %H:%M') }}</td>
</tr>
<tr>
<th>Login Count</th>
<td>{{ current_user.login_count }}</td>
</tr>
<tr>
<th>Staff Status</th>
<td>{{ 'Yes' if current_user.is_staff else 'No' }}</td>
</tr>
</table>
<button type="submit">Update Profile</button>
</form>
</div>
<div class="card">
<h2>Activity Reports</h2>
<p>Generate a report of your account activity:</p>
<div style="margin: 20px 0;">
<button onclick="generateReport('summary')">Summary Report</button>
<button onclick="generateReport('detailed')">Detailed Report</button>
</div>
<div id="report-result" style="display: none;" class="message"></div>
</div>
<div class="card">
<h2>Error Tracking Demo</h2>
<p>Click a button to trigger an error and see it captured in PostHog:</p>
<div style="margin: 20px 0;">
<button class="danger" onclick="triggerError('value')">
Trigger ValueError
</button>
<button class="danger" onclick="triggerError('key')">
Trigger KeyError
</button>
<button class="danger" onclick="triggerError('generic')">
Trigger Generic Error
</button>
</div>
<div id="error-result" style="display: none;" class="message"></div>
</div>
<div class="card">
<h3>Code Example</h3>
<pre>
try:
raise ValueError('Invalid value provided')
except Exception as e:
# Capture exception and event with user context
with new_context():
identify_context(current_user.email)
posthog.capture_exception(e)
capture('error_triggered', properties={
'error_type': 'value',
'error_message': str(e)
})</pre>
</div>
{% endblock %}
{% block scripts %}
<script>
async function triggerError(errorType) {
const resultDiv = document.getElementById('error-result');
try {
const formData = new FormData();
formData.append('error_type', errorType);
const response = await fetch('/api/trigger-error', {
method: 'POST',
body: formData
});
const data = await response.json();
resultDiv.style.display = 'block';
resultDiv.className = 'message ' + (data.success ? 'success' : 'error');
resultDiv.textContent = data.message + ': ' + data.error;
} catch (error) {
console.error('Error:', error);
resultDiv.style.display = 'block';
resultDiv.className = 'message error';
resultDiv.textContent = 'Request failed: ' + error.message;
}
}
async function generateReport(reportType) {
const resultDiv = document.getElementById('report-result');
try {
const formData = new FormData();
formData.append('report_type', reportType);
const response = await fetch('/api/reports/activity', {
method: 'POST',
body: formData
});
const data = await response.json();
resultDiv.style.display = 'block';
resultDiv.className = 'message success';
resultDiv.innerHTML = '<strong>' + data.report_type + ' report generated</strong> (' + data.row_count + ' rows)<br><pre>' + JSON.stringify(data.data, null, 2) + '</pre>';
} catch (error) {
console.error('Error:', error);
resultDiv.style.display = 'block';
resultDiv.className = 'message error';
resultDiv.textContent = 'Request failed: ' + error.message;
}
}
</script>
{% endblock %}
app/templates/signup.html
{% extends "base.html" %}
{% block title %}Sign Up - PostHog FastAPI Example{% endblock %}
{% block content %}
<div class="card">
<h1>Create an Account</h1>
<p>Sign up to explore the PostHog FastAPI integration example.</p>
<form method="POST">
<label for="email">Email *</label>
<input type="email" id="email" name="email" required>
<label for="password">Password *</label>
<input type="password" id="password" name="password" required>
<label for="password_confirm">Confirm Password *</label>
<input type="password" id="password_confirm" name="password_confirm" required>
<button type="submit">Sign Up</button>
</form>
<p style="margin-top: 16px; font-size: 14px; color: #666;">
Already have an account? <a href="/">Login here</a>
</p>
</div>
<div class="card">
<h2>PostHog Integration</h2>
<p>When you sign up, the following PostHog events are captured:</p>
<ul style="margin-left: 20px; color: #666;">
<li><code>identify_context()</code> - Associates your email with the context</li>
<li><code>tag()</code> - Sets person properties (email, etc.)</li>
<li><code>user_signed_up</code> event - Tracks the signup action</li>
</ul>
<h3 style="margin-top: 20px;">Code Example</h3>
<pre>
# After creating the user
with new_context():
identify_context(user.email)
tag('email', user.email)
tag('is_staff', user.is_staff)
tag('date_joined', user.date_joined.isoformat())
capture('user_signed_up', properties={'signup_method': 'form'})</pre>
</div>
{% endblock %}
requirements.txt
fastapi>=0.109.0
uvicorn>=0.27.0
sqlalchemy>=2.0.0
python-dotenv>=1.0.0
posthog>=3.0.0
pydantic>=2.0.0
pydantic-settings>=2.0.0
jinja2>=3.0.0
python-multipart>=0.0.9
werkzeug>=3.0.0
itsdangerous>=2.0.0
run.py
"""Development server entry point."""
import uvicorn
if __name__ == "__main__":
uvicorn.run("app.main:app", host="0.0.0.0", port=5002, reload=True)
Requirements and compatibility
Works with: Claude Code, Claude apps, OpenAI Codex, GitHub Copilot, Cursor, Gemini CLI, Kiro, OpenCode, Goose, Amp, Roo Code, JetBrains Junie, Factory Droid, Devin (ex-Windsurf), Mistral Vibe, OpenHands, Letta
“Works with” means the tool reads the open Agent Skills format; a skill written for one tool may use features others lack.
Needs: Needs an MCP server, Needs Python, Needs Node.js
Security
What our scanner noticed· Low risk
- Instructions that use the network
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Attribution and licence
- Created by
- PostHog
- Publisher
- PostHog (Official)
- Source
- PostHog/skills · skills/omnibus/instrument-product-analytics · commit a5d30e7
- Licence
- MIT License (redistribution allowed)
- LICENSE (added by AutoGineer from LICENSE)
- ATTRIBUTION.md (written by AutoGineer)
- Synced
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Download ZIP
The ZIP holds the skill’s files, its licence files and an ATTRIBUTION.md. Download instrument-product-analytics.zip