Tilt

Tilt is a multi-service dev environment for teams on Kubernetes.

Github repository

Getting started

Run command tilt up in the project directory and go to the Tilt dashboard page. The dashboard will show error because we don't have a Tiltfile yet.

Tilt is controlled using Tiltfile, the first function print prints a string to Tilt logs stream.

print('Hello Tiltfile')
docker_build('pras/simple-python-server', '.')
k8s_yaml('app.yaml')
k8s_resource('simple-python-server', port_forwards=8080)

Prepare application source file, e.g., app.py.

from http.server import BaseHTTPRequestHandler, HTTPServer


class SimpleHTTPRequestHandler(BaseHTTPRequestHandler):
    def do_GET(self):
        self.send_response(200)
        self.end_headers()
        self.wfile.write(b"Hello, World!\n")


server = HTTPServer(("0.0.0.0", 8080), SimpleHTTPRequestHandler)
server.serve_forever()

Function docker_build will build the application based on existing Dockerfile.

FROM python:3.8-slim
WORKDIR /app
COPY . /app
EXPOSE 8080
CMD ["python", "/app/app.py"]

Function k8s_yaml will deploy the container image created from the previous line using manifest file app.yaml.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: simple-python-server
  labels:
    app: simple-python-server
spec:
  selector:
    matchLabels:
      app: simple-python-server
  template:
    metadata:
      labels:
        app: simple-python-server
    spec:
      containers:
        - name: simple-python-server
          image: pras/simple-python-server
          ports:
            - containerPort: 8080

The function k8s_resource will monitor the kubernetes resources with label app: simple-python-server and expose the application using port forwarding to port 8080.