ci: Pick up the right branches when building a windows image

Now we will pick up the right gstreamer branch + namespace when
building an image, and also the right (matching, if any) cerbero
branch + namespace.

This solves the bootstrapping issue when doing an image update that
requires coordination between gstreamer and cerbero.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5043>

.gitlab-ci.yml

@@ -180,14 +180,12 @@ windows amd64 docker:
     - "2022"
   script:
     # We need to pass an array and to resolve the env vars, so we can't use a variable:
-    - $DOCKER_BUILD_ARGS = @("--build-arg", "DEFAULT_BRANCH=$GST_UPSTREAM_BRANCH")
-
-    - "& ci/docker/windows/container.ps1 $CI_REGISTRY $CI_REGISTRY_USER $CI_REGISTRY_PASSWORD $WINDOWS_IMAGE $WINDOWS_UPSTREAM_IMAGE $DOCKERFILE"
-    - |
-      if (!($?)) {
-        echo "Failed to build the image"
-        Exit 1
-      }
+    - $DOCKER_BUILD_ARGS = @(`
+        "--build-arg", "DEFAULT_BRANCH=$GST_UPSTREAM_BRANCH", `
+        "--build-arg", "CI_PROJECT_NAMESPACE=$CI_PROJECT_NAMESPACE", `
+        "--build-arg", "CI_COMMIT_REF_NAME=$CI_COMMIT_REF_NAME" `
+      )
+    - ci/docker/windows/container.ps1 $CI_REGISTRY $CI_REGISTRY_USER $CI_REGISTRY_PASSWORD $WINDOWS_IMAGE $WINDOWS_UPSTREAM_IMAGE $DOCKERFILE
 
 
 # ---- Preparation ----- #

ci/docker/windows/Dockerfile

@@ -54,7 +54,7 @@ RUN C:\upgrade_msys2.ps1
 
 RUN C:\msys64\msys2_shell.cmd -ucrt64 -defterm -here -no-start -use-full-path -lc 'pacman -S --noconfirm mingw-w64-ucrt-x86_64-toolchain ninja'
 
-RUN python -m pip install meson==1.1.1
+RUN python -m pip install meson==1.1.1 python-gitlab
 
 RUN 'git config --global user.email "cirunner@gstreamer.freedesktop.org"; git config --global user.name "GStreamer CI system"'
 
@@ -62,9 +62,15 @@ COPY install_rust.ps1 C:\
 RUN C:\install_rust.ps1
 
 ARG DEFAULT_BRANCH="main"
+ARG CI_PROJECT_NAMESPACE
+ARG CI_COMMIT_REF_NAME
 
+ENV CI_PROJECT_NAMESPACE=$CI_PROJECT_NAMESPACE
+ENV CI_COMMIT_REF_NAME=$CI_COMMIT_REF_NAME
 COPY prepare_gst_env.ps1 C:\
 RUN C:\prepare_gst_env.ps1
 
+ENV CI="true"
+COPY get_cerbero_clone_args.py C:\
 COPY prepare_cerbero_env.sh  C:\
 RUN C:\msys64\msys2_shell.cmd -ucrt64 -defterm -here -no-start -use-full-path -lc "C:/prepare_cerbero_env.sh"

ci/docker/windows/get_cerbero_clone_args.py

@@ -0,0 +1,27 @@
+#!/usr/bin/python3
+
+import os
+import gitlab
+
+
+server = 'https://gitlab.freedesktop.org'
+gl = gitlab.Gitlab(server)
+branch = os.environ.get('DEFAULT_BRANCH', 'main')
+project = f'gstreamer/cerbero'
+# We do not want to run on (often out of date) user upstream branch
+if os.environ["CI_COMMIT_REF_NAME"] != os.environ['DEFAULT_BRANCH']:
+    try:
+        try_project = f'{os.environ["CI_PROJECT_NAMESPACE"]}/cerbero'
+        match_branch = os.environ["CI_COMMIT_REF_NAME"]
+        # Search for matching branches, return only if the branch name matches
+        # exactly
+        proj = gl.projects.get(try_project)
+        for b in proj.branches.list(search=match_branch, iterator=True):
+            if match_branch == b.name:
+                project = try_project
+                branch = b.name
+                break
+    except gitlab.exceptions.GitlabGetError:
+        pass
+
+print(f'-b {branch} {server}/{project}', end='')

ci/docker/windows/prepare_cerbero_env.sh

@@ -2,8 +2,12 @@
 
 set -eux
 
-cd C:/
-git clone -b ${DEFAULT_BRANCH} https://gitlab.freedesktop.org/gstreamer/cerbero.git C:/cerbero
+# Clone `-b main gstreamer/cerbero` by default, but if running on a gstreamer
+# branch in another namespace that has a corresponding cerbero branch by the
+# same name, clone that instead.
+clone_args="$(py -3 C:/get_cerbero_clone_args.py)"
+echo "Cloning Cerbero using $clone_args"
+git clone $clone_args C:/cerbero
 cd C:/cerbero
 
 echo 'local_sources="C:/cerbero/cerbero-sources"' > localconf.cbc

ci/docker/windows/prepare_gst_env.ps1

@@ -14,8 +14,13 @@ $secure_pw = ConvertTo-SecureString $plaintext_pw -AsPlainText -Force
 C:\msys64\ucrt64\bin\openssl.exe pkcs12 -export -nokeys -out $env:TEMP\certs.pfx -in $cert_pem -passout pass:$plaintext_pw
 Import-PfxCertificate -Password $secure_pw  -CertStoreLocation Cert:\LocalMachine\Root -FilePath $env:TEMP\certs.pfx
 
-Write-Host "Cloning GStreamer"
-git clone -b $env:DEFAULT_BRANCH https://gitlab.freedesktop.org/gstreamer/gstreamer.git C:\gstreamer
+$namespace = "gstreamer"
+if ($env:CI_COMMIT_REF_NAME -ne $env:DEFAULT_BRANCH) {
+  $namespace = $env:CI_PROJECT_NAMESPACE
+}
+$url = "https://gitlab.freedesktop.org/$namespace/gstreamer.git"
+Write-Host "Cloning GStreamer branch $env:CI_COMMIT_REF_NAME from $url"
+git clone -b $env:CI_COMMIT_REF_NAME $url C:\gstreamer
 
 # download the subprojects to try and cache them
 Write-Host "Downloading subprojects"