Support charmcraft 3 and multi platform builds

.github/workflows/check.yaml

@@ -91,7 +91,7 @@ jobs:
         - 'tox -e func -- -v --base ubuntu@24.04 --keep-models'
         juju-channel: ["3.4/stable"]
         exclude:
-        # NOTE(rgildein): The grafana-agent does not support ubuntu@24.04 on arm64. See #347 
+        # NOTE(rgildein): The grafana-agent does not support ubuntu@24.04 on arm64. See #347
         - test-command: 'tox -e func -- -v --base ubuntu@24.04 --keep-models'
           runs-on: [Ubuntu_ARM64_4C_16G_01]
     steps:
@@ -116,7 +116,7 @@ jobs:
         with:
           provider: "lxd"
           juju-channel: ${{ matrix.juju-channel }}
-          charmcraft-channel: "2.x/stable"
+          charmcraft-channel: "3.x/stable"
 
         # This is used by zaza in the functional tests for non-amd64 architectures (if applicable)
       - name: Set zaza juju model constraints for architecture

.github/workflows/promote.yaml

@@ -36,4 +36,4 @@ jobs:
           credentials: ${{ secrets.CHARMHUB_TOKEN }}
           destination-channel: ${{ steps.set-channels.outputs.destination-channel }}
           origin-channel: ${{ steps.set-channels.outputs.origin-channel }}
-          charmcraft-channel: "2.x/stable"
+          charmcraft-channel: "3.x/stable"

.github/workflows/release.yaml

@@ -36,7 +36,7 @@ jobs:
       - name: Pack and upload to charmhub
         uses: canonical/charming-actions/upload-charm@2.6.2
         with:
-          charmcraft-channel: "2.x/stable"
+          charmcraft-channel: "3.x/stable"
           credentials: "${{ secrets.CHARMHUB_TOKEN }}"
           github-token: "${{ secrets.GITHUB_TOKEN }}"
           # Ensure the charm is built in an isolated environment and on the correct base in an lxd container.

charmcraft.yaml

@@ -1,50 +1,22 @@
 # Learn more about charmcraft.yaml configuration at:
 # https://juju.is/docs/sdk/charmcraft-config
 # This is a template `charmcraft.yaml` file for ops charms
-# This file is managed by bootstack-charms-spec and should not be modified
-# within individual charm repos. https://launchpad.net/bootstack-charms-spec
 
 type: charm
 
 parts:
   charm:
+    plugin: charm
+    source: .
     build-packages: [git]
 
-bases:
-  - build-on:
-    - name: ubuntu
-      channel: "22.04"
-      architectures: ["amd64"]
-    run-on:
-      - name: ubuntu
-        channel: "24.04"
-        architectures:
-          - amd64
-      - name: ubuntu
-        channel: "22.04"
-        architectures:
-          - amd64
-      - name: ubuntu
-        channel: "20.04"
-        architectures:
-          - amd64
-  - build-on:
-    - name: ubuntu
-      channel: "22.04"
-      architectures: ["arm64"]
-    run-on:
-      - name: ubuntu
-        channel: "24.04"
-        architectures:
-          - arm64
-      - name: ubuntu
-        channel: "22.04"
-        architectures:
-          - arm64
-      - name: ubuntu
-        channel: "20.04"
-        architectures:
-          - arm64
+platforms:
+  ubuntu@20.04:amd64:
+  ubuntu@22.04:amd64:
+  ubuntu@24.04:amd64:
+  ubuntu@20.04:arm64:
+  ubuntu@22.04:arm64:
+  ubuntu@24.04:arm64:
 
 actions:
   redetect-hardware: