feature: create charm for deployment

Author: edisile

app.py

@@ -0,0 +1,15 @@
+# This file serves as an entry point for the rock image. It is required by the PaaS app charmer.
+# The flask application must be defined in this file under the variable name `app`.
+# See - https://documentation.ubuntu.com/rockcraft/en/latest/reference/extensions/flask-framework/
+import os
+import logging
+
+# canonicalwebteam.flask-base requires SECRET_KEY to be set, this must be done before importing the app
+os.environ["SECRET_KEY"] = os.environ["FLASK_SECRET_KEY"]
+
+# disable talisker logger, as it is not used in this application and clutters logs
+logging.getLogger("talisker.context").disabled = True
+
+from webapp.app import create_app
+
+app = create_app()

charm/.gitignore

@@ -0,0 +1,10 @@
+venv/
+build/
+*.charm
+.tox/
+.coverage
+__pycache__/
+*.py[cod]
+.idea
+.vscode/
+lib/

charm/README.md

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+# The Charm for the snapcraft.io website
+
+This charm was created using the [PaaS App Charmer](https://juju.is/docs/sdk/paas-charm)
+
+## Local development
+
+To work on this charm locally, you first need to set up an environment, follow [this section](https://juju.is/docs/sdk/write-your-first-kubernetes-charm-for-a-flask-app#heading--set-things-up) of the tutorial.
+
+Then, you can run the following command to pack and upload the rock:
+
+```bash
+rockcraft pack
+rockcraft.skopeo --insecure-policy copy --dest-tls-verify=false oci-archive:snapcraft-io*.rock docker://localhost:32000/snapcraft-io:1
+```
+
+This will pack the application into a [rock](https://documentation.ubuntu.com/rockcraft/en/latest/explanation/rocks/) (OCI image) and upload it to the local registry.
+
+You can deploy the charm locally with:
+
+```bash
+cd charm
+charmcraft fetch-libs
+charmcraft pack
+juju deploy ./*.charm --resource flask-app-image=localhost:32000/snapcraft-io:1
+```
+
+This will deploy the charm with the rock image you just uploaded attached as a resource.
+
+once `juju status` reports the charm as `active`, you can test the webserver:
+
+```bash
+curl {IP_OF_SNAPCRAFT_IO_UNIT}:8000
+```
+
+to connect using a browser, the easiest way is to integrate with `nginx-ingress-integrator`:
+
+```bash
+juju deploy nginx-ingress-integrator --trust
+juju config nginx-ingress-integrator service-hostname=snapcraft.local path-routes=/
+juju integrate nginx-ingress-integrator snapcraft-io
+```
+
+You can then add `snapcraft.local` to your `/etc/hosts` file with the IP of the multipass vm:
+
+```bash
+multipass ls # Get the IP of the VM
+echo "{IP_OF_VM} snapcraft.local" | sudo tee -a /etc/hosts
+```
+
+> Note: login will not work using this setup, if you'd like to access publisher pages, change the domain to `staging.snapcraft.io`, but make sure to remove the line from `/etc/hosts/` after you're done.
+
+
+## Design Decisions:
+- To keep the codebase clean and charm libraries updated, they are only fetched before packing the charm in the [Github Actions workflow](https://github.com/canonical/snapcraft.io/blob/main/.github/workflows/publish_charm.yaml#L25).
+- As all our work is open source, the charm is publicly available on [snapcraft](https://charmhub.io/snapcraft-io), the rock image is also included as a resource. This significantly simplifies deployment.

charm/charmcraft.yaml

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+name: snapcraft-io
+
+type: charm
+
+bases:
+  - build-on:
+    - name: ubuntu
+      channel: "22.04"
+    run-on:
+    - name: ubuntu
+      channel: "22.04"
+
+summary: The charm for the snapcraft.io website
+
+description: The charm for the snapcraft.io website, built with the PaaS app charmer
+
+extensions:
+  - flask-framework
+
+requires:
+  tracing:
+    interface: tracing
+    optional: true
+    limit: 1

charm/requirements.txt

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+ops ~= 2.17
+paas-charm>=1.0,<2

charm/src/charm.py

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+#!/usr/bin/env python3
+
+"""Flask Charm entrypoint."""
+
+import logging
+import typing
+
+import ops
+
+import paas_charm.flask
+
+logger = logging.getLogger(__name__)
+
+
+class CharmCharm(paas_charm.flask.Charm):
+    """Flask Charm service."""
+
+    def __init__(self, *args: typing.Any) -> None:
+        """Initialize the instance.
+
+        Args:
+            args: passthrough to CharmBase.
+        """
+        super().__init__(*args)
+
+
+if __name__ == "__main__":
+    ops.main(CharmCharm)

yarn.lock

@@ -3310,9 +3310,9 @@ camelcase@^6.2.0:
   integrity sha512-Gmy6FhYlCY7uOElZUSbxo2UCDH8owEk996gkbrpsgGtrJLM3J7jGxl9Ic7Qwwj4ivOE5AWZWRMecDdF7hqGjFA==
 
 caniuse-lite@^1.0.30001646, caniuse-lite@^1.0.30001688:
-  version "1.0.30001690"
-  resolved "https://registry.yarnpkg.com/caniuse-lite/-/caniuse-lite-1.0.30001690.tgz#f2d15e3aaf8e18f76b2b8c1481abde063b8104c8"
-  integrity sha512-5ExiE3qQN6oF8Clf8ifIDcMRCRE/dMGcETG/XGMD8/XiXm6HXQgQTh1yZYLXXpSOsEUlJm1Xr7kGULZTuGtP/w==
+  version "1.0.30001726"
+  resolved "https://registry.npmjs.org/caniuse-lite/-/caniuse-lite-1.0.30001726.tgz"
+  integrity sha512-VQAUIUzBiZ/UnlM28fSp2CRF3ivUn1BWEvxMcVTNwpw91Py1pGbPIyIKtd+tzct9C3ouceCVdGAXxZOpZAsgdw==
 
 chalk@^3.0.0:
   version "3.0.0"