Okteto Cloud gives instant access to secure Kubernetes namespaces to enable developers to code, build, and run Kubernetes applications entirely in the cloud.
This tutorial will show you how to develop and debug a Python sample application running in Okteto Cloud.
- Install the Okteto CLI >= 1.9.0. Follow this guide if you haven't done it yet.
- Configure Access to your Okteto Cloud Namespace using the Okteto CLI or using the Okteto Cloud UI.
Step 1: Deploy the Python Sample App
Get a local version of the Python Sample App by executing the following commands:
$ git clone https://github.com/okteto/python-getting-started$ cd python-getting-started
k8s.yml file contains the Kubernetes manifests of the Python Sample App.
Deploy a dev version of the application by executing:
$ kubectl apply -f k8s.yml
deployment.apps "hello-world" createdservice "hello-world" created
Log into Okteto Cloud and click on the URL of the application:
Did you notice that you are accessing your application through an HTTPs endpoint? This is because Okteto Cloud will automatically create them for you when you deploy your application. Cool no 😎?
Step 2: Create your okteto manifest
To start developing on the Python Sample App you first need to create an okteto manifest. With the Python Sample App deployed, run the following command to create your okteto manifest:
$ okteto init
This command walks you through creating an okteto manifest.It only covers the most common items, and tries to guess sensible defaults.See https://okteto.com/docs/reference/manifest for the official documentation about the okteto manifest.Use the arrow keys to navigate: ↓ ↑ → ←Select the deployment you want to develop:▸ hello-worldUse default values
okteto init command will scan the available deployments in your Kubernetes namespace, and ask you to pick one.
hello-world deployment. It's the one we deployed on the previous step.
✓ hello-world✓ Deployment 'hello-world' successfully analyzed✓ okteto manifest (okteto.yml) createdi Run 'okteto up' to activate your development container
okteto init command creates the following
name: hello-worldimage: okteto/python:3command: bashvolumes:- /root/.cache/pipsync:- .:/usr/src/appforward:- 8080:8080reverse:- 9000:9000resources:limits:cpu: "1"memory: 2Gi
This file defines how to activate a development container for the Python Sample App:
name: the name of the Kubernetes deployment you want to put on development mode.
image: the image used by the development container. More information on development images here.
command: the start command of the development container.
volumes: a list of paths in your development container to be mounted as persistent volumes. This is useful to persist the pip cache.
sync: the folders that will be synchronized between your local machine and the development container.
forward: a list of ports to forward from your development container.
reverse: a list of ports to reverse forward from your development container to your local machine.
resources: the resources configuration (CPU and memory) of the development container.
okteto init command creates a
.stignore file to indicate which files shouldn't be synchronized to your development container.
This is useful to avoid virtual environments, build artifacts or git metadata.
Step 3: Activate your development container
Next, execute the following command to activate your development container:
$ okteto up
✓ Development container activated✓ Files synchronizedNamespace: cindyName: hello-worldSSH: 60224 -> 2222Forward: 8080 -> 8080Reverse: 9000 <- 9000Welcome to your development container. Happy coding!cindy:hello-world app>
Working in your development container is the same as working on your local machine. Start by creating a virtual environment:
cindy:hello-world app> python -m venv env
and activate it:
cindy:hello-world app> source env/bin/activate
Install your pip dependencies (your dependencies will be persisted in future
okteto up executions):
(env) cindy:hello-world app> pip install -r requirements.txt
Collecting Click==7.0Downloading Click-7.0-py2.py3-none-any.whl (81 kB)|████████████████████████████████| 81 kB 2.7 MB/sCollecting Flask==1.1.1Downloading Flask-1.1.1-py2.py3-none-any.whl (94 kB)|████████████████████████████████| 94 kB 2.8 MB/sCollecting itsdangerous==1.1.0Downloading itsdangerous-1.1.0-py2.py3-none-any.whl (16 kB)Collecting Jinja2==2.10.3Downloading Jinja2-2.10.3-py2.py3-none-any.whl (125 kB)|████████████████████████████████| 125 kB 24.0 MB/sCollecting MarkupSafe==1.1.1Downloading MarkupSafe-1.1.1.tar.gz (19 kB)Collecting pydevd-pycharm==192.7142.79Downloading pydevd-pycharm-192.7142.79.tar.gz (3.2 MB)|████████████████████████████████| 3.2 MB 23.2 MB/sCollecting Werkzeug==0.16.0Downloading Werkzeug-0.16.0-py2.py3-none-any.whl (327 kB)|████████████████████████████████| 327 kB 34.3 MB/sUsing legacy 'setup.py install' for MarkupSafe, since package 'wheel' is not installed.Using legacy 'setup.py install' for pydevd-pycharm, since package 'wheel' is not installed.Installing collected packages: Click, MarkupSafe, Jinja2, Werkzeug, itsdangerous, Flask, pydevd-pycharmRunning setup.py install for MarkupSafe ... doneRunning setup.py install for pydevd-pycharm ... doneSuccessfully installed Click-7.0 Flask-1.1.1 Jinja2-2.10.3 MarkupSafe-1.1.1 Werkzeug-0.16.0 itsdangerous-1.1.0 pydevd-pycharm-192.7142.79
Start the application in development mode by running the following command:
cindy:hello-world app> python app.py
Starting hello-world server...* Serving Flask app "app" (lazy loading)* Environment: development* Debug mode: on* Running on http://0.0.0.0:8080/ (Press CTRL+C to quit)
Go back to the browser, and reload the page to test that your application is running.
Step 4: Develop directly on Okteto Cloud
app.py file in your favorite local IDE and modify the response message on line 7 to be Hello world from the cluster!.
Save your changes.
@app.route('/')def hello_world():return 'Hello World from the cluster!'}
Okteto will synchronize your changes to your development container in Kubernetes. Flask's auto-reloader will detect the changes automatically and restart the application with the new code.
* Detected change in '/usr/src/app/app.py', reloading* Restarting with statStarting hello-world server...* Debugger is active!* Debugger PIN: 308-916-374
Go back to the browser and reload the page. Your code changes were instantly applied. No commit, build or push required 😎!
Step 5: Debug directly in Okteto Cloud
Okteto enables you to debug your applications directly from your favorite IDE. Let's take a look at how that works in one of python's most popular IDE's, PyCharm.
For VS Code users, this document explains how to configure the debugger with
First, open the project in PyCharm, remove the comments on
if __name__ == '__main__':print('Starting hello-world server...')# comment out to use Pycharm's remote debuggerattach()app.run(host='0.0.0.0', port=8080)
Second, launch the Remote Debug Server by clicking on the Debug button on the top right.
Ensure that the Debug Tool Window shows the
Waiting for process connection.. message. This message will be shown until you launch your app on the development container shell and it connects to the Debug Server.
Starting hello-world server...* Serving Flask app "app" (lazy loading)* Environment: development* Debug mode: on* Running on http://0.0.0.0:8080/ (Press CTRL+C to quit)* Restarting with statStarting hello-world server...Connecting to debugger...
On your local machine, switch to the Debug Tool Window. Once the app connects it will show the connection to the pydev debugger.
resume button to let the execution continue.
Add a breakpoint on
app.py, line 10. Go back to the browser, and reload the page.
The execution will halt at your breakpoint. You can then inspect the request, the available variables, etc.
Your code is executing in Okteto Cloud, but you can debug it from your local machine without any extra services or tools. Pretty cool no? 😉
Congratulations, you just developed your first application in Okteto Cloud 🚀.
Okteto lets you develop your applications directly on Kubernetes. This way you can:
- Eliminate integration issues by developing in a realistic environment
- Test your application end to end as fast as you type code
- No more CPU cycles wasted in your machine. Develop at the speed of the cloud!
Ready to develop your application on Okteto Cloud? Read our step by step tutorial on how to configure an Okteto Pipeline to deploy realistic environments for your application in just one click.