armbian-next: somewhat-better handling/logging when using Docker (don't show two logfiles to inspect)

- do not show path to Docker run-host's logfile, unless the Docker run itself didn't produce logs
- introduce `global_final_exit_code` to allow to maintain/preserve Docker's exit code without triggering an error host-side

lib/functions/cli/cli-docker.sh

@@ -42,8 +42,20 @@ function cli_docker_run() {
 			;;
 
 		*)
+			# this does NOT exit with the same exit code as the docker instance.
+			# instead, it sets the docker_exit_code variable.
+			declare -i docker_exit_code docker_produced_logs=0
 			docker_cli_launch "${ARMBIAN_CLI_RELAUNCH_ARGS[@]}" # MARK: this "re-launches" using the passed params.
+
+			# Set globals to avoid:
+			# 1) showing the controlling host's log; we only want to show a ref to the Docker logfile, unless it didn't produce one.
+			if [[ $docker_produced_logs -gt 0 ]]; then
+				declare -g show_message_after_export="skip" # handled by export_ansi_logs()
+			fi
+			# 2) actually exiting with the same error code as the docker instance, but without triggering an error.
+			declare -g -i global_final_exit_code=$docker_exit_code # handled by .... @TODO
 			;;
+
 	esac
 
 }

lib/functions/host/docker.sh

@@ -407,27 +407,37 @@ function docker_cli_launch() {
 	display_alert "Showing Docker cmdline" "Docker args: '${DOCKER_ARGS[*]}'" "debug"
 
 	display_alert "Relaunching in Docker" "${*}" "debug"
-	display_alert "-----------------Relaunching in Docker-----------------------------------" "here comes the 🐳" "info"
+	display_alert "-----------------Relaunching in Docker------------------------------------" "here comes the 🐳" "info"
 
-	local -i docker_build_result=1
+	local -i docker_build_result
 	if docker run -it "${DOCKER_ARGS[@]}" "${DOCKER_ARMBIAN_INITIAL_IMAGE_TAG}" /bin/bash "${DOCKER_ARMBIAN_TARGET_PATH}/compile.sh" "$@"; then
-		display_alert "-------------Docker Build finished----------------------------------------" "successfully" "info"
-		docker_build_result=0
+		docker_build_result=$? # capture exit code of test done in the line above.
+		display_alert "-------------Docker run finished------------------------------------------" "successfully" "info"
 	else
-		display_alert "-------------Docker Build failed-------------------------------------------" "with errors" "err"
+		docker_build_result=$? # capture exit code of test done 4 lines above.
+		display_alert "-------------Docker run failed--------------------------------------------" "with errors" "err"
 	fi
 
 	# Find and show the path to the log file for the ARMBIAN_BUILD_UUID.
 	local logs_path="${DEST}/logs" log_file
 	log_file="$(find "${logs_path}" -type f -name "*${ARMBIAN_BUILD_UUID}*.*" -print -quit)"
-	display_alert "Build log done inside Docker" "${log_file}" "info"
+	docker_produced_logs=0 # outer scope variable
+	if [[ -f "${log_file}" ]]; then
+		docker_produced_logs=1 # outer scope variable
+		display_alert "Build log done inside Docker" "${log_file}" "debug"
+	else
+		display_alert "Docker Log file for this run" "not found" "err"
+	fi
 
 	# Show and help user understand space usage in Docker volumes.
 	# This is done in a loop; `docker df` fails sometimes (for no good reason).
 	# @TODO: this is very, very slow when the volumes are full. disable.
 	# docker_cli_show_armbian_volumes_disk_usage
 
-	return ${docker_build_result}
+	docker_exit_code="${docker_build_result}" # set outer scope variable -- do NOT exit with error.
+
+	# return ${docker_build_result}
+	return 0 # always exit with success. caller (CLI) will handle the exit code
 }
 
 function docker_cli_show_armbian_volumes_disk_usage() {

lib/functions/logging/export-logs.sh

@@ -104,5 +104,9 @@ function export_ansi_logs() {
 	declare target_relative_to_src
 	target_relative_to_src="$(realpath --relative-to="${SRC}" "${target_file}")"
 
-	display_alert "ANSI log file built; inspect it by running:" "less -RS ${target_relative_to_src}"
+	if [[ "${show_message_after_export:-"yes"}" != "skip" ]]; then
+		display_alert "ANSI log file built; inspect it by running:" "less -RS ${target_relative_to_src}"
+	fi
+	
+	return 0
 }

lib/functions/logging/traps.sh

@@ -77,6 +77,14 @@ function main_trap_handler() {
 
 			# Run the cleanup handlers, always.
 			run_cleanup_handlers || true
+
+			# If global_final_exit_code is set, use it as the exit code. (used by docker CLI handler)
+			if [[ -n "${global_final_exit_code}" ]]; then
+				display_alert "Final exit code" "Final exit code ${global_final_exit_code}" "debug"
+				# disable the trap, so we don't get called again.
+				trap - EXIT
+				exit "${global_final_exit_code}"
+			fi
 			;;
 		*)
 			display_alert "main_trap_handler" "Unknown trap type '${trap_type}'" "err"