Build separately for each supported series and use binary builds

Charms for OpenStack Yoga supports both Ubuntu Focal and Jammy
which means Python 3.8 and Python 3.10.  Managing dependencies
across those two versions is non-trivial and we need to build
the charm on the series the charm is supposed to support.

Switch to using a binary build which allows pip's dependency
resolution to work.

Change-Id: I1bf4aac08cf7388fec4550d40887a8df45927589

charmcraft.yaml

@@ -2,24 +2,76 @@ type: charm
 
 parts:
   charm:
-    source: src/
-    plugin: reactive
-    build-snaps:
-      - charm
+    build-packages:
+      - tox
+      - git
+      - python3-dev
+      - libffi-dev
+      - libssl-dev
+      - rustc
+      - cargo
     build-environment:
       - CHARM_INTERFACES_DIR: /root/project/interfaces/
       - CHARM_LAYERS_DIR: /root/project/layers/
+      - MAKEFLAGS: -j$(nproc)
+    override-build: |
+      apt-get install ca-certificates -y
+      tox -e build-reactive
+    override-stage: |
+      echo "Copying charm to staging area: $CRAFT_STAGE"
+      NAME=$(ls $CRAFT_PART_BUILD/build/builds)
+      cp -r $CRAFT_PART_BUILD/build/builds/$NAME/* $CRAFT_STAGE/
+    override-prime: |
+      # For some reason, the normal priming chokes on the fact that there's a
+      # hooks directory.
+      cp -r $CRAFT_STAGE/* .
+      # Charmcraft looks for this specific entry point.
+      mkdir -p src
+      touch src/charm.py
+      chmod +x src/charm.py
 
 bases:
   - build-on:
       - name: ubuntu
         channel: "22.04"
-        architectures:
-          - amd64
+        architectures: [amd64]
     run-on:
       - name: ubuntu
         channel: "22.04"
-        architectures: [amd64, s390x, ppc64el, arm64]
+        architectures: [amd64]
       - name: ubuntu
         channel: "22.10"
-        architectures: [amd64, s390x, ppc64el, arm64]
+        architectures: [amd64]
+  - build-on:
+      - name: ubuntu
+        channel: "22.04"
+        architectures: [arm64]
+    run-on:
+      - name: ubuntu
+        channel: "22.04"
+        architectures: [arm64]
+      - name: ubuntu
+        channel: "22.10"
+        architectures: [arm64]
+  - build-on:
+      - name: ubuntu
+        channel: "22.04"
+        architectures: [ppc64el]
+    run-on:
+      - name: ubuntu
+        channel: "22.04"
+        architectures: [ppc64el]
+      - name: ubuntu
+        channel: "22.10"
+        architectures: [ppc64el]
+  - build-on:
+      - name: ubuntu
+        channel: "22.04"
+        architectures: [s390x]
+    run-on:
+      - name: ubuntu
+        channel: "22.04"
+        architectures: [s390x]
+      - name: ubuntu
+        channel: "22.10"
+        architectures: [s390x]

src/tests/bundles/jammy-yoga.yaml

@@ -90,7 +90,7 @@ applications:
     - '7'
 
   designate:
-    charm: ../../../designate.charm
+    charm: ../../../designate_ubuntu-22.04-amd64_ubuntu-22.10-amd64.charm
     num_units: 1
     options:
       nameservers: 'ns1.amuletexample.com. ns2.amuletexample.com.'

src/tests/bundles/jammy-zed.yaml

@@ -90,7 +90,7 @@ applications:
     - '7'
 
   designate:
-    charm: ../../../designate.charm
+    charm: ../../../designate_ubuntu-22.04-amd64_ubuntu-22.10-amd64.charm
     num_units: 1
     options:
       nameservers: 'ns1.amuletexample.com. ns2.amuletexample.com.'

src/tests/bundles/kinetic-zed.yaml

@@ -90,7 +90,7 @@ applications:
     - '7'
 
   designate:
-    charm: ../../../designate.charm
+    charm: ../../../designate_ubuntu-22.04-amd64_ubuntu-22.10-amd64.charm
     num_units: 1
     options:
       nameservers: 'ns1.amuletexample.com. ns2.amuletexample.com.'

tox.ini

@@ -11,18 +11,6 @@ envlist = pep8,py3
 sitepackages = False
 # NOTE: Avoid false positives by not skipping missing interpreters.
 skip_missing_interpreters = False
-# NOTES:
-# * We avoid the new dependency resolver by pinning pip < 20.3, see
-#   https://github.com/pypa/pip/issues/9187
-# * Pinning dependencies requires tox >= 3.2.0, see
-#   https://tox.readthedocs.io/en/latest/config.html#conf-requires
-# * It is also necessary to pin virtualenv as a newer virtualenv would still
-#   lead to fetching the latest pip in the func* tox targets, see
-#   https://stackoverflow.com/a/38133283
-requires =
-  pip < 20.3
-  virtualenv < 20.0
-  setuptools<50.0.0
 
 # NOTE: https://wiki.canonical.com/engineering/OpenStack/InstallLatestToxOnOsci
 minversion = 3.18.0
@@ -33,13 +21,14 @@ setenv = VIRTUAL_ENV={envdir}
          TERM=linux
          JUJU_REPOSITORY={toxinidir}/build
 passenv = no_proxy http_proxy https_proxy JUJU_REPOSITORY
+# We can stop using pip.sh when charmcraft snap includes new version of git:
+# https://github.com/canonical/charmcraft/issues/875
 install_command =
   {toxinidir}/pip.sh install {opts} {packages}
 allowlist_externals =
     charmcraft
     bash
     tox
-    rename.sh
 deps =
     -r{toxinidir}/requirements.txt
 
@@ -49,12 +38,11 @@ deps = -r{toxinidir}/build-requirements.txt
 commands =
     charmcraft clean
     charmcraft -v pack
-    {toxinidir}/rename.sh
 
 [testenv:build-reactive]
 basepython = python3
 commands =
-    charm-build --log-level DEBUG --use-lock-file-branches -o {toxinidir}/build/builds src {posargs}
+    charm-build --log-level DEBUG --use-lock-file-branches --binary-wheels-from-source -o {toxinidir}/build/builds src {posargs}
 
 [testenv:add-build-lock-file]
 basepython = python3