From d86afe1e97a4cd06c41486a9d465063647d7ecf1 Mon Sep 17 00:00:00 2001 From: Tony Meyer Date: Wed, 18 Dec 2024 22:11:13 +1300 Subject: [PATCH] Remove file that seems to be accidentally commited. --- ...n-of-the-application-behind-your-charm.md# | 124 ------------------ 1 file changed, 124 deletions(-) delete mode 100644 docs/tutorial/from-zero-to-hero-write-your-first-kubernetes-charm/#expose-the-version-of-the-application-behind-your-charm.md# diff --git a/docs/tutorial/from-zero-to-hero-write-your-first-kubernetes-charm/#expose-the-version-of-the-application-behind-your-charm.md# b/docs/tutorial/from-zero-to-hero-write-your-first-kubernetes-charm/#expose-the-version-of-the-application-behind-your-charm.md# deleted file mode 100644 index 2cc19f05e..000000000 --- a/docs/tutorial/from-zero-to-hero-write-your-first-kubernetes-charm/#expose-the-version-of-the-application-behind-your-charm.md# +++ /dev/null @@ -1,124 +0,0 @@ -(expose-the-version-of-the-application-behind-your-charm)= -# Expose the version of the application behind your charm - -> {ref}`From Zero to Hero: Write your first Kubernetes charm ` > Expose the version of the application behind your charm -> -> **See previous: {ref}`Make your charm configurable `** - -````{important} - -This document is part of a series, and we recommend you follow it in sequence. However, you can also jump straight in by checking out the code from the previous branches: - -``` -git clone https://github.com/canonical/juju-sdk-tutorial-k8s.git -cd juju-sdk-tutorial-k8s -git checkout 02_make_your_charm_configurable -git checkout -b 03_set_workload_version -``` - -```` - -In this chapter of the tutorial you will learn how to expose the version of the application (workload) run by the charm -- something that a charm user might find it useful to know. - -**Contents:** - -1. [Define functions to collect the workload application version and set it in the charm](#heading--define-functions-to-collect-the-workload-application-version-and-set-it-in-the-charm) -1. [Declare Python dependencies](#heading--declare-python-dependencies) -1. [Validate your charm](#heading--validate-your-charm) -1. [Review the final code](#heading--review-the-final-code) - -

Define functions to collect the workload application version and set it in the charm

 - -As a first step we need to add two helper functions that will send an HTTP request to our application to get its version. If the container is available, we can send a request using the `requests` Python library and then add class methods to parse the JSON output to get a version string, as shown below: - -- Import the `requests` Python library: - -``` -import requests -``` - -- Add the following class methods: - - -```python -@property -def version(self) -> str: - """Reports the current workload (FastAPI app) version.""" - try: - if self.container.get_services(self.pebble_service_name): - return self._request_version() - # Catching Exception is not ideal, but we don't care much for the error here, and just - # default to setting a blank version since there isn't much the admin can do! - except Exception as e: - logger.warning("unable to get version from API: %s", str(e), exc_info=True) - return "" - -def _request_version(self) -> str: - """Helper for fetching the version from the running workload using the API.""" - resp = requests.get(f"http://localhost:{self.config['server-port']}/version", timeout=10) - return resp.json()["version"] -``` - -Next, we need to update the `_update_layer_and_restart` method to set our workload version. Insert the following lines before setting `ActiveStatus`: - -```python -# Add workload version in Juju status. -self.unit.set_workload_version(self.version) -``` - -

Declare Python dependencies

 - - -Since we've added a third party Python dependency into our project, we need to list it in `requirements.txt`. Edit the file to add the following line: - -``` -requests~=2.28 -``` - -Next time you run `charmcraft` it will fetch this new dependency into the charm package. - - -

Validate your charm

 - -We've exposed the workload version behind our charm. Let's test that it's working! - -First, repack and refresh your charm: - -``` -charmcraft pack -juju refresh \ - --path="./demo-api-charm_ubuntu-22.04-amd64.charm" \ - demo-api-charm --force-units --resource \ - demo-server-image=ghcr.io/canonical/api_demo_server:1.0.1 -``` - -Our charm should fetch the application version and forward it to `juju`. Run `juju status` to check: - -```text -juju status -``` - -Indeed, the version of our workload is now displayed -- see the App block, the Version column: - -```text -Model Controller Cloud/Region Version SLA Timestamp -charm-model tutorial-controller microk8s/localhost 3.0.0 unsupported 12:37:27+01:00 - -App Version Status Scale Charm Channel Rev Address Exposed Message -demo-api-charm 1.0.1 active 1 demo-api-charm 0 10.152.183.233 no - -Unit Workload Agent Address Ports Message -demo-api-charm/0* active idle 10.1.157.75 -``` - -

Review the final code

 - - -For the full code see: [03_set_workload_version](https://github.com/canonical/juju-sdk-tutorial-k8s/tree/03_set_workload_version) - -For a comparative view of the code before and after this doc see: [Comparison](https://github.com/canonical/juju-sdk-tutorial-k8s/compare/02_make_your_charm_configurable...03_set_workload_version) - - -> **See next: {ref}`Integrate your charm with PostgreSQL `** - -> Contributors: @beliaev-maksim \ No newline at end of file