Template structure (#2)

* Add initial charm structure

* Add type hint for Pebble layer and use services attribute

* Change name of the operator

Co-authored-by: Jon Seager <[email protected]>

* Move testing and usage instructions to CONTRIBUTING.md

* Add storage

* Generate postgres user password instead of user provided password

* Add missing imports

* Subscription to on pebble ready event

* Add tests structure from template

* Remove default environment variables

Co-authored-by: Jon Seager <[email protected]>

* Add type hint

Co-authored-by: Daniela Plascencia <[email protected]>

* Change to get container from event workload

* Improve readability of layers and services

Co-authored-by: Mia Altieri <[email protected]>

* Implement peer relation

Co-authored-by: Jon Seager <[email protected]>
Co-authored-by: Daniela Plascencia <[email protected]>
Co-authored-by: Mia Altieri <[email protected]>

.github/workflows/ci.yaml

@@ -0,0 +1,36 @@
+name: Tests
+on: [pull_request, push]
+
+jobs:
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Install dependencies
+        run: python3 -m pip install tox
+      - name: Run linters
+        run: tox -e lint
+  unit-test:
+    name: Unit tests
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Install dependencies
+        run: python -m pip install tox
+      - name: Run tests
+        run: tox -e unit
+  integration-test-microk8s:
+    name: Integration tests (microk8s)
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Setup operator environment
+        uses: charmed-kubernetes/actions-operator@main
+        with:
+          provider: microk8s
+      - name: Run integration tests
+        run: tox -e integration

.gitignore

@@ -0,0 +1,7 @@
+venv/
+build/
+*.charm
+
+.coverage
+__pycache__/
+*.py[cod]

.jujuignore

@@ -0,0 +1,3 @@
+/venv
+*.py[cod]
+*.charm

CONTRIBUTING.md

@@ -0,0 +1,59 @@
+# Contributing
+
+## Overview
+
+This documents explains the processes and practices recommended for contributing enhancements to
+this operator.
+
+- Generally, before developing enhancements to this charm, you should consider [opening an issue
+  ](https://github.com/canonical/postgresql-k8s-operator/issues) explaining your use case.
+- If you would like to chat with us about your use-cases or proposed implementation, you can reach
+  us at [Canonical Mattermost public channel](https://chat.charmhub.io/charmhub/channels/charm-dev)
+  or [Discourse](https://discourse.charmhub.io/).
+- Familiarising yourself with the [Charmed Operator Framework](https://juju.is/docs/sdk) library
+  will help you a lot when working on new features or bug fixes.
+- All enhancements require review before being merged. Code review typically examines
+  - code quality
+  - test coverage
+  - user experience for Juju administrators this charm.
+- Please help us out in ensuring easy to review branches by rebasing your pull request branch onto
+  the `main` branch. This also avoids merge commits and creates a linear Git commit history.
+
+## Developing
+
+You can use the environments created by `tox` for development:
+
+```shell
+tox --notest -e unit
+source .tox/unit/bin/activate
+```
+
+### Testing
+
+```shell
+tox -e fmt           # update your code according to linting rules
+tox -e lint          # code style
+tox -e unit          # unit tests
+tox -e integration   # integration tests
+tox                  # runs 'lint' and 'unit' environments
+```
+
+## Build charm
+
+Build the charm in this git repository using:
+
+```shell
+charmcraft pack
+```
+
+### Deploy
+
+```bash
+# Create a model
+juju add-model dev
+# Enable DEBUG logging
+juju model-config logging-config="<root>=INFO;unit=DEBUG"
+# Deploy the charm
+juju deploy ./postgresql-k8s_ubuntu-20.04-amd64.charm \
+    --resource postgresql-image=ubuntu/postgres
+```

LICENSE

@@ -0,0 +1,202 @@
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README.md

@@ -1 +1,19 @@
-Coming soon
+# PostgreSQL Kubernetes Operator
+
+## Description
+
+The PostgreSQL Kubernetes Operator deploys and operates the [PostgreSQL](https://www.postgresql.org/about/) database on Kubernetes clusters.
+
+This operator provides a Postgres database with replication enabled (one master instance and one or more hot standby replicas). The Operator in this repository is a Python script which wraps the LTS Postgres versions distributed by [Ubuntu](https://hub.docker.com/r/ubuntu/postgres), providing lifecycle management and handling events (install, configure, integrate, remove).
+
+## Usage
+
+As this charm is not yet published, you need to follow the build and deploy instructions from [CONTRIBUTING.md](CONTRIBUTING.md).
+
+## Accessing the database
+
+You can access the database using any PostgreSQL client by connecting on the unit address and port `5432` as user `postgres` with the password shown by the command below.
+
+```bash
+juju run-action postgresql-k8s/0 get-postgres-password --wait
+```

actions.yaml

@@ -0,0 +1,5 @@
+# Copyright 2021 Canonical Ltd.
+# See LICENSE file for licensing details.
+
+get-postgres-password:
+  description: Get the initial postgres user password for the database.

charmcraft.yaml

@@ -0,0 +1,12 @@
+type: "charm"
+bases:
+  - build-on:
+    - name: "ubuntu"
+      channel: "20.04"
+    run-on:
+    - name: "ubuntu"
+      channel: "20.04"
+parts:
+  charm:
+    build-packages:
+      - git

metadata.yaml

@@ -0,0 +1,31 @@
+# Copyright 2021 Canonical Ltd.
+# See LICENSE file for licensing details.
+
+name: postgresql-k8s
+display-name: PostgreSQL K8s
+description: |
+  Charm to operate the PostgreSQL database on Kubernetes clusters
+summary: |
+  Charm to operate the PostgreSQL database on Kubernetes clusters
+
+containers:
+  postgresql:
+    resource: postgresql-image
+    mounts:
+      - storage: pgdata
+        location: /var/lib/postgresql/data/pgdata
+
+resources:
+  postgresql-image:
+    type: oci-image
+    description: OCI image for PostgreSQL (ubuntu/postgres)
+    upstream-source: ubuntu/postgres:12-20.04_beta
+
+peers:
+  postgresql-replicas:
+    interface: postgresql-replicas
+
+storage:
+  pgdata:
+    type: filesystem
+    location: /var/lib/postgresql/data/pgdata