ci-automation/image-changes: Fix some redirection issues

First issue is that on Jenkins, the beginning of the output seems to
be eaten, leaving us only the final part of the reports. This looks
like an issue stemming from redirecting stdout to stdout with
">/dev/stdout". Special case the stdout by not redirecting anything in
such case.

Second issue is that errors printed by the tools we use for generating
the reports go to stderr, so they don't show in the report. So
redirect their stderr to stdout, so the possible errors are visible in
the report file too. We do not want to redirect the stderr of the
print_image_reports function, because that would also capture
debugging stuff from "set -x" that GitHub Actions are using.

ci-automation/image_changes.sh

@@ -83,7 +83,7 @@ function image_changes() (
     echo "Image URL: http://${BUILDCACHE_SERVER}/images/${arch}/${vernum}/flatcar_production_image.bin.bz2"
     echo
     generate_image_changes_report \
-        "${arch}" "${channel}" "${vernum}" /dev/stdout "${fbs_repo}" "${work_directory}" \
+        "${arch}" "${channel}" "${vernum}" '-' "${fbs_repo}" "${work_directory}" \
         "${package_diff_env[@]}" --- "${package_diff_params_b[@]}" -- \
         "${size_changes_env[@]}" --- "${size_changes_params_b[@]}" -- \
         "${show_changes_env[@]}" --- "${show_changes_params_overrides[@]}"
@@ -177,14 +177,21 @@ function generate_image_changes_report() (
         "${show_changes_params[@]}"
     )
 
-    {
+    local print_image_reports_invocation=(
-        # Using "|| :" to avoid failing the job.
+        print_image_reports
-        print_image_reports \
+        "${flatcar_build_scripts_repo}" "${channel_a}" "${version_a}" "${work_directory}"
-            "${flatcar_build_scripts_repo}" "${channel_a}" "${version_a}" "${work_directory}" \
+        "${package_diff_env[@]}" --- "${package_diff_params[@]}" --
-            "${package_diff_env[@]}" --- "${package_diff_params[@]}" -- \
+        "${size_changes_env[@]}" --- "${size_changes_params[@]}" --
-            "${size_changes_env[@]}" --- "${size_changes_params[@]}" -- \
+        "${show_changes_env[@]}" --- "${show_changes_params[@]}"
-            "${show_changes_env[@]}" --- "${show_changes_params[@]}" || :
+    )
-    } >"${report_output}"
+    # Using "|| :" to avoid failing the job.
+    if [[ ${report_output} = '-' ]]; then
+        "${print_image_reports_invocation[@]}" || :
+    else
+        {
+            "${print_image_reports_invocation[@]}" || :
+        } >"${report_output}"
+    fi
 )
 # --
 
@@ -301,25 +308,25 @@ function print_image_reports() {
     env \
         --chdir="${work_directory}" \
         "${package_diff_env[@]}" FILE=flatcar_production_image_packages.txt \
-        "${flatcar_build_scripts_repo}/package-diff" "${package_diff_params[@]}"
+        "${flatcar_build_scripts_repo}/package-diff" "${package_diff_params[@]}" 2>&1
     echo
     echo "Image file changes, compared to ${channel_a} ${version_a}:"
     env \
         --chdir="${work_directory}" \
         "${package_diff_env[@]}" FILE=flatcar_production_image_contents.txt FILESONLY=1 CUTKERNEL=1 \
-        "${flatcar_build_scripts_repo}/package-diff" "${package_diff_params[@]}"
+        "${flatcar_build_scripts_repo}/package-diff" "${package_diff_params[@]}" 2>&1
     echo
     echo "Image kernel config changes, compared to ${channel_a} ${version_a}:"
     env \
         --chdir="${work_directory}" \
         "${package_diff_env[@]}" FILE=flatcar_production_image_kernel_config.txt \
-        "${flatcar_build_scripts_repo}/package-diff" "${package_diff_params[@]}"
+        "${flatcar_build_scripts_repo}/package-diff" "${package_diff_params[@]}" 2>&1
     echo
     echo "Image init ramdisk file changes, compared to ${channel_a} ${version_a}:"
     env \
         --chdir="${work_directory}" \
         "${package_diff_env[@]}" FILE=flatcar_production_image_initrd_contents.txt FILESONLY=1 \
-        "${flatcar_build_scripts_repo}/package-diff" "${package_diff_params[@]}"
+        "${flatcar_build_scripts_repo}/package-diff" "${package_diff_params[@]}" 2>&1
     echo
 
     local size_changes_invocation=(
@@ -329,13 +336,13 @@ function print_image_reports() {
         "${flatcar_build_scripts_repo}/size-change-report.sh"
     )
     echo "Image file size changes, compared to ${channel_a} ${version_a}:"
-    if ! "${size_changes_invocation[@]}" "${size_change_report_params[@]/%/:wtd}"; then
+    if ! "${size_changes_invocation[@]}" "${size_change_report_params[@]/%/:wtd}" 2>&1; then
-        "${size_changes_invocation[@]}" "${size_change_report_params[@]/%/:old}"
+        "${size_changes_invocation[@]}" "${size_change_report_params[@]/%/:old}" 2>&1
     fi
     echo
     echo "Image init ramdisk file size changes, compared to ${channel_a} ${version_a}:"
-    if ! "${size_changes_invocation[@]}" "${size_change_report_params[@]/%/:initrd-wtd}"; then
+    if ! "${size_changes_invocation[@]}" "${size_change_report_params[@]/%/:initrd-wtd}" 2>&1; then
-        "${size_changes_invocation[@]}" "${size_change_report_params[@]/%/:initrd-old}"
+        "${size_changes_invocation[@]}" "${size_change_report_params[@]/%/:initrd-old}" 2>&1
     fi
     echo "Take the total size difference with a grain of salt as normally initrd is compressed, so the actual difference will be smaller."
     echo "To see the actual difference in size, see if there was a report for /boot/flatcar/vmlinuz-a."
@@ -346,7 +353,7 @@ function print_image_reports() {
     env \
         --chdir="${work_directory}" \
         "${package_diff_env[@]}" FILE=flatcar_production_image_contents.txt CALCSIZE=1 \
-        "${flatcar_build_scripts_repo}/package-diff" "${package_diff_params[@]}"
+        "${flatcar_build_scripts_repo}/package-diff" "${package_diff_params[@]}" 2>&1
     echo
 
     local param
@@ -359,7 +366,7 @@ function print_image_reports() {
         "${show_changes_env[@]}" \
         "${flatcar_build_scripts_repo}/show-changes" \
         "${SHOW_CHANGES_NEW_CHANNEL}-${SHOW_CHANGES_NEW_CHANNEL_PREV_VERSION}" \
-        "${SHOW_CHANGES_NEW_VERSION}"
+        "${SHOW_CHANGES_NEW_VERSION}" 2>&1
     # See if a channel transition happened and print the changelog against ${channel_a} ${version_a} which is the previous release
     if [ "${channel_a}" != "${SHOW_CHANGES_NEW_CHANNEL}" ]; then
         env \
@@ -367,7 +374,7 @@ function print_image_reports() {
             "${show_changes_env[@]}" \
             "${flatcar_build_scripts_repo}/show-changes" \
             "${channel_a}-${version_a}" \
-            "${SHOW_CHANGES_NEW_VERSION}"
+            "${SHOW_CHANGES_NEW_VERSION}" 2>&1
     fi
 }
 # --