Rewrite with handling of the Collector thing

tasks/determine-image-tag-task.yaml

@@ -45,33 +45,83 @@ spec:
 
       set -euo pipefail
 
-      dnf -y install git make
+      function main() {
+        dnf -y install git make
+
+        fail_build_if_git_is_dirty
+
+        local suffix="$(params.TAG_SUFFIX)"
+        local source_branch="$(params.SOURCE_BRANCH)"
+
+        local image_tag
+        image_tag="$(determine_tag)"
+
+        echo -n "${image_tag}${suffix}" | tee "$(results.IMAGE_TAG.path)"
+      }
 
       function fail_build_if_git_is_dirty() {
         echo "Checking that there are no uncommitted changes in the git repo."
         echo "If this command fails, you should see the list of modified files below."
         echo "You need to find the reason and prevent it because otherwise the 'make tag' output will include '-dirty' which likely isn't what you want."
         echo ""
 
-        if git status --porcelain | grep '.' >&2 ; then
+        if git status --porcelain | grep "." >&2 ; then
           >&2 echo "ERROR: Modified files found."
           exit 2
         else
           echo "git repo looks clean."
         fi
       }
 
-      fail_build_if_git_is_dirty
+      function determine_tag() {
+        function log() {
+          # Log to stderr so not to mess up function's printed result.
+          >&2 echo "$@"
+        }
+
+        # 1. Gather data
+
+        local tag_from_tekton=""
+        if [[ "${source_branch}" == refs/tags/* ]]; then
+          tag_from_tekton="${source_branch#refs/tags/}"
+        fi
+        log "Tag from Tekton event: '${tag_from_tekton}'"
+
+        local tag_from_makefile
+        tag_from_makefile="$(make -C "$(params.MAKEFILE_DIRECTORY)" --quiet --no-print-directory tag)"
+        log "Tag reported by Makefile: '${tag_from_makefile}'"
+
+        local tags_from_git
+        tags_from_git="$(git tag --points-at)"
+        local -a tags_from_git_arr
+        readarray tags_from_git_arr <<< "${tags_from_git}"
+        log "Tags seen by git: '${tags_from_git_arr[*]}'"
+
+        local git_describe_output
+        git_describe_output="$(git describe --tags --abbrev=10 --dirty --long)"
+        log "Long git describe output: '${git_describe_output}'"
+
+        # 2. Decide
 
-      source_branch="$(params.SOURCE_BRANCH)"
-      suffix="$(params.TAG_SUFFIX)"
+        if [[ -n "${tag_from_tekton}" ]]; then
+          log "This seems to be a tekton tag push event, using ${tag_from_tekton} for the tag."
+          echo "${tag_from_tekton}"
+          return
+        fi
+
+        # Handle the special case in the Collector repo.
+        if printf '%s\0' "${tags_from_git_arr[@]}" | grep -qzFx -- "${tag_from_makefile}"; then
+          log "This is not a tag push event but Makefile reports literally the git tag ${tag_from_makefile}."
+          log "This happens when a build was triggered not by a tag push event but the commit is tagged and when the Makefile doesn't use '--long' with 'git describe'."
+          log "We should use a different image tag for this build in order to not mix results with a build that was triggered by a tag push event and which will tag its images as ${tag_from_makefile}."
+          log "Using ${git_describe_output} for the tag."
+          echo "${git_describe_output}"
+          return
+        fi
 
-      if [[ "${source_branch}" == refs/tags/* ]]; then
-        echo "${source_branch} seems to be a build of a git tag, will use this git tag."
-        image_tag="${source_branch#refs/tags/}"
-      else
-        # Otherwise, delegate the work to Makefiles.
-        image_tag="$(make -C "$(params.MAKEFILE_DIRECTORY)" --quiet --no-print-directory tag)"
-      fi
+        log "Using Makefile output ${tag_from_makefile} for the tag."
+        echo "${tag_from_makefile}"
+        return
+      }
 
-      echo -n "${image_tag}${suffix}" | tee "$(results.IMAGE_TAG.path)"
+      main