# Flask Integration URL: /kida/docs/tutorials/flask-integration/ Section: tutorials Description: Use Kida templates with Flask web framework --- > For a complete page index, fetch /kida/llms.txt. Integrate Kida templates into your Flask application. ## Prerequisites - Python 3.14+ - Flask installed - Basic Flask knowledge ## Step 1: Install Dependencies ```bash pip install flask kida ``` ## Step 2: Configure Kida with Flask Create a Flask app with Kida templates: ```python from flask import Flask, request from kida import Environment, FileSystemLoader app = Flask(__name__) # Configure Kida environment kida_env = Environment( loader=FileSystemLoader("templates/"), autoescape=True, ) # Add Flask-specific globals kida_env.add_global("url_for", lambda *a, **kw: "#") # Replace with real url_for kida_env.add_global("request", request) ``` ## Step 3: Create a Render Helper ```python from flask import make_response def render_template(template_name, **context): """Render a Kida template.""" template = kida_env.get_template(template_name) html = template.render(**context) return make_response(html) ``` ## Step 4: Use in Routes ```python @app.route("/") def home(): return render_template("home.html", title="Welcome") @app.route("/users/") def user_profile(name): user = get_user(name) return render_template("profile.html", user=user) ``` ## Step 5: Create Templates **templates/base.html:** ```kida {% block title %}My App{% end %}

{% block content %}{% end %}

``` **templates/home.html:** ```kida {% extends "base.html" %} {% block title %}{{ title }}{% end %} {% block content %}

Welcome to the site!

{% end %} ``` ## Complete Example ```python from flask import Flask, request, make_response from kida import Environment, FileSystemLoader app = Flask(__name__) # Kida environment with caching kida_env = Environment( loader=FileSystemLoader("templates/"), autoescape=True, cache_size=100, auto_reload=app.debug, # Only reload in debug mode ) def render_template(template_name, **context): template = kida_env.get_template(template_name) html = template.render(**context) response = make_response(html) response.headers["Content-Type"] = "text/html" return response @app.route("/") def home(): return render_template("home.html", title="Home") @app.route("/about") def about(): return render_template("about.html", title="About") if __name__ == "__main__": app.run(debug=True) ``` ## Custom Filters for Flask ```python from datetime import datetime from flask import url_for as flask_url_for # Add Flask's url_for kida_env.add_global("url_for", flask_url_for) # Add custom filters @kida_env.filter() def format_datetime(value, format="%Y-%m-%d"): if isinstance(value, datetime): return value.strftime(format) return value @kida_env.filter() def pluralize(count, singular, plural=None): if plural is None: plural = singular + "s" return singular if count == 1 else plural ``` Use in templates: ```kida {{ post.date | format_datetime("%B %d, %Y") }} {{ count }} {{ count | pluralize("item") }} ``` ## Error Handling ```python from kida import TemplateError @app.errorhandler(TemplateError) def handle_template_error(error): app.logger.error(f"Template error: {error}") return render_template("error.html", error=str(error)), 500 ``` ## Production Configuration ```python # Production settings kida_env = Environment( loader=FileSystemLoader("templates/"), autoescape=True, auto_reload=False, # Don't check for changes cache_size=400, # Larger cache ) # Clear cache on deploy @app.cli.command() def clear_cache(): """Clear template cache.""" kida_env.clear_cache() print("Template cache cleared.") ``` ## FastAPI Integration Kida works similarly with FastAPI: ```python from fastapi import FastAPI from fastapi.responses import HTMLResponse from kida import Environment, FileSystemLoader app = FastAPI() kida_env = Environment(loader=FileSystemLoader("templates/")) @app.get("/", response_class=HTMLResponse) def home(): template = kida_env.get_template("home.html") return template.render(title="FastAPI + Kida") ``` ## Next Steps - [[docs/extending/custom-filters|Custom Filters]] — Build domain-specific filters - [[docs/usage/escaping|Escaping]] — HTML security - [[docs/about/performance|Performance]] — Production optimization