[Buildroot] [RFC v2] utils/test-pkg: add gitlab-ci support

[Romain Naour]

The gitlab-ci support in test-pkg allow to parallelize the test-pkg
work into several gitlab jobs. It's much faster than local serialized
testing.

The current generate-gitlab-ci-yml script is updated to detect any
branches using a suffix "*-test-pkg" to generate a gitlab-ci pipeline
using the newly introcuded .test_pkg job template.

The test-pkg script is executed in the generated-gitlab-ci job to
create the list of jobs in the child-pipeline. There is no need to
execute test-pkg locally. But we need to add a new --gitlab-ci (-g)
option to generate .config and .config.old files for each
toolchains without building them. All configuration files are keept
as gitlab artifacts for the child-pipeline jobs.
(We can't keep br-test-pkg directory due to a 5 Mo limit size in gilbab)

Only valid toolchains are added to the child-pipeline job list.

To execure test-pkg we need to provide a config snippet to select
the package we want to test. The config snippet must be added to the
last commit log bellow the line "test-pkg config:"
The config snipped is retrieved in generated-gitlab-ci job using
CI_COMMIT_DESCRIPTION gitlab variable.

Signed-off-by: Romain Naour <romain.naour at gmail.com>
Cc: Arnout Vandecappelle (Essensium/Mind) <arnout at mind.be>
---
v2: Rework this patch following Arnout review
    use CI_COMMIT_DESCRIPTION
    remove .config from artifacts but keep images directory since
    it can be useful for further issue investigation
    use the "br-test-pkg" prefix for test-pkg jobs

See:
https://gitlab.com/kubu93/buildroot/-/pipelines/302286694
---
 .gitlab-ci.yml                         |  3 +++
 support/misc/gitlab-ci.yml.in          | 25 +++++++++++++++++++++++++
 support/scripts/generate-gitlab-ci-yml | 19 +++++++++++++++++++
 utils/test-pkg                         | 24 ++++++++++++++++++++----
 4 files changed, 67 insertions(+), 4 deletions(-)

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index e85ac32033..9c8c82ac69 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -13,6 +13,9 @@ generate-gitlab-ci-yml:
   artifacts:
     paths:
       - generated-gitlab-ci.yml
+      - br-test-pkg/*/.config
+      - br-test-pkg/*/.config.old
+      - test-pkg.log
 
 buildroot-pipeline:
   stage: build
diff --git a/support/misc/gitlab-ci.yml.in b/support/misc/gitlab-ci.yml.in
index fcfff5c6aa..5292f3e7f4 100644
--- a/support/misc/gitlab-ci.yml.in
+++ b/support/misc/gitlab-ci.yml.in
@@ -76,3 +76,28 @@
             - test-output/*/.config
             - test-output/*/images/*
 
+.test_pkg:
+    before_script:
+        - TEST_PKG_BUILD=${CI_JOB_NAME}
+    script:
+        - echo "Configure Buildroot for ${TEST_PKG_BUILD}"
+        - make O=${TEST_PKG_BUILD} olddefconfig
+        - make O=${TEST_PKG_BUILD} savedefconfig
+        - make O=${TEST_PKG_BUILD}
+        - echo 'Build buildroot'
+        - |
+            make O=${TEST_PKG_BUILD} > >(tee build.log |grep '>>>') 2>&1 || {
+                echo 'Failed build last output'
+                tail -200 build.log
+                exit 1
+            }
+    artifacts:
+        when: always
+        expire_in: 2 weeks
+        paths:
+            - build.log
+            - br-test-pkg/*/.config
+            - br-test-pkg/*/defconfig
+            - br-test-pkg/*/images/
+            - br-test-pkg/*/build/build-time.log
+            - br-test-pkg/*/build/packages-file-list.txt
diff --git a/support/scripts/generate-gitlab-ci-yml b/support/scripts/generate-gitlab-ci-yml
index 3f498e08fd..5149bd60ee 100755
--- a/support/scripts/generate-gitlab-ci-yml
+++ b/support/scripts/generate-gitlab-ci-yml
@@ -74,12 +74,25 @@ gen_tests() {
             runtimes=( "${CI_COMMIT_REF_NAME##*-}" )
             do_runtime=true
             ;;
+          (*-test-pkg)
+            # Retrieve defconfig from the git commit message
+            echo "$CI_COMMIT_DESCRIPTION" \
+                | sed -n '/^test-pkg config:$/,/^$/p' \
+                > defconfig.frag
+            # Remove "test-pkg config:" line
+            sed -i 1d defconfig.frag
+            # Use -a since we expect the user having already pre-tested the new package
+            # with the default subset of toolchains.
+            ./utils/test-pkg -c defconfig.frag -a -d br-test-pkg -k -g 2>&1 > test-pkg.log
+            toolchains=( $(find br-test-pkg -mindepth 1 -maxdepth 1 -type d '!' -exec test -e "{}/missing.config" ';' -execdir basename '{}' ';') )
+            do_testpkg=yes
         esac
     fi
 
     # If nothing else, at least do the basics to generate a valid pipeline
     if [    -z "${do_defconfigs}" \
          -a -z "${do_runtime}" \
+         -a -z "${do_testpkg}" \
        ]
     then
         do_basics=true
@@ -101,6 +114,12 @@ gen_tests() {
     if ${do_runtime:-false}; then
         printf '%s: { extends: .runtime_test_base }\n' "${runtimes[@]}"
     fi
+
+    if [ -n "${do_testpkg}" ]; then
+        for cfg in "${toolchains[@]}"; do
+            printf '%s: { extends: .test_pkg }\n' "br-test-pkg/${cfg}"
+        done
+    fi
 }
 
 main "${@}"
diff --git a/utils/test-pkg b/utils/test-pkg
index a317d8c17a..ba479c01fa 100755
--- a/utils/test-pkg
+++ b/utils/test-pkg
@@ -12,13 +12,13 @@ do_clean() {
 
 main() {
     local o O opts
-    local cfg dir pkg random toolchains_csv toolchain all number mode
+    local cfg dir pkg random toolchains_csv toolchain all number mode gitlab_ci
     local ret nb nb_skip nb_fail nb_legal nb_tc build_dir keep
     local -a toolchains
     local pkg_br_name
 
-    o='hakc:d:n:p:r:t:'
-    O='help,all,keep,config-snippet:,build-dir:,number:,package:,random:,toolchains-csv:'
+    o='hakgc:d:n:p:r:t:'
+    O='help,all,keep,gitlab-ci,config-snippet:,build-dir:,number:,package:,random:,toolchains-csv:'
     opts="$(getopt -n "${my_name}" -o "${o}" -l "${O}" -- "${@}")"
     eval set -- "${opts}"
 
@@ -27,6 +27,7 @@ main() {
     keep=0
     number=0
     mode=0
+    gitlab_ci=0
     toolchains_csv="${TOOLCHAINS_CSV}"
     while [ ${#} -gt 0 ]; do
         case "${1}" in
@@ -39,6 +40,9 @@ main() {
         (-k|--keep)
             keep=1; shift 1
             ;;
+        (-g|--gitlab-ci)
+            gitlab_ci=1; shift 1
+            ;;
         (-c|--config-snippet)
             cfg="${2}"; shift 2
             ;;
@@ -118,6 +122,11 @@ main() {
         printf "error: no toolchain found (networking issue?)\n" >&2; exit 1
     fi
 
+    if [ ${gitlab_ci} -eq 1  ]; then
+        # Running in gitlab-ci imply keep the build directories.
+        keep=1
+    fi
+
     nb=0
     nb_skip=0
     nb_fail=0
@@ -127,12 +136,13 @@ main() {
         toolchain="$(basename "${toolchainconfig}" .config)"
         build_dir="${dir}/${toolchain}"
         printf "%40s [%*d/%d]: " "${toolchain}" ${#nb_tc} ${nb} ${nb_tc}
-        build_one "${build_dir}" "${toolchainconfig}" "${cfg}" "${pkg}" && ret=0 || ret=${?}
+        build_one "${build_dir}" "${toolchainconfig}" "${cfg}" "${pkg}" "${gitlab_ci}" && ret=0 || ret=${?}
         case ${ret} in
         (0) printf "OK\n";;
         (1) : $((nb_skip++)); printf "SKIPPED\n";;
         (2) : $((nb_fail++)); printf "FAILED\n";;
         (3) : $((nb_legal++)); printf "FAILED\n";;
+        (4) printf "GITLAB CI\n";;
         esac
     done
 
@@ -147,6 +157,7 @@ build_one() {
     local toolchainconfig="${2}"
     local cfg="${3}"
     local pkg="${4}"
+    local gitlab_ci="${5}"
 
     mkdir -p "${dir}"
 
@@ -166,6 +177,11 @@ build_one() {
     # Remove file, it's empty anyway.
     rm -f "${dir}/missing.config"
 
+    # Differ to gitlab pipeline
+    if [ ${gitlab_ci} -eq 1  ]; then
+        return 4
+    fi
+
     if [ -n "${pkg}" ]; then
         if ! make O="${dir}" "${pkg}-dirclean" >> "${dir}/logfile" 2>&1; then
             return 2
-- 
2.31.1