Move debug log dump from ynh_exit_properly to the core after failed app operation

data/helpers.d/utils

@@ -28,43 +28,6 @@ ynh_exit_properly () {
 	# Small tempo to avoid the next message being mixed up with other DEBUG messages
 	sleep 0.5
 
-	ynh_print_err --message="!!\n  $app's script has encountered an error. Its execution was cancelled.\n!!"
-
-	# If the script is executed from the CLI, dump the end of the log that precedes the crash.
-	if [ "$YNH_INTERFACE" == "cli" ]
-	then
-		# Unset xtrace to not spoil the log
-		set +x
-
-		local ynh_log="/var/log/yunohost/yunohost-cli.log"
-
-		# Wait for the log to be fill with the data until the crash.
-		local timeout=0
-		while ! tail --lines=20 "$ynh_log" | grep --quiet "+ ynh_exit_properly"
-		do
-			((timeout++))
-			if [ $timeout -eq 500 ]; then
-				break
-			fi
-		done
-
-		echo -e "\e[34m\e[1mPlease find here an extract of the log before the crash:\e[0m" >&2
-		# Tail the last 30 lines of log of YunoHost
-		# But remove all lines after "ynh_exit_properly"
-		# Remove the timestamp at the beginning of the line
-		# Remove "yunohost.hook..."
-		# Add DEBUG and color it at the beginning of each log line.
-		echo -e "$(tail --lines=30 "$ynh_log" \
-			| sed '1,/+ ynh_exit_properly/!d' \
-			| sed 's/^[[:digit:]: ,-]*//g' \
-			| sed 's/ *yunohost.hook.*\]/ -/g' \
-			| sed 's/^WARNING /&/g' \
-			| sed 's/^DEBUG /&  /g' \
-			| sed 's/^INFO /&   /g' \
-			| sed 's/^/\\e[34m\\e[1m[DEBUG]\\e[0m: /g')" >&2
-		set -x
-	fi
-
 	if type -t ynh_clean_setup > /dev/null; then	# Check if the function exist in the app script.
 		ynh_clean_setup	# Call the function to do specific cleaning for the app.
 	fi

src/yunohost/app.py

@@ -738,6 +738,8 @@ def app_upgrade(app=[], url=None, file=None):
                 error = m18n.n('app_upgrade_script_failed')
                 logger.exception(m18n.n("app_upgrade_failed", app=app_instance_name, error=error))
                 failure_message_with_debug_instructions = operation_logger.error(error)
+                if msettings.get('interface') != 'api':
+                    dump_app_log_extract_for_debugging(operation_logger)
         # Script got manually interrupted ... N.B. : KeyboardInterrupt does not inherit from Exception
         except (KeyboardInterrupt, EOFError):
             upgrade_retcode = -1
@@ -1002,6 +1004,8 @@ def app_install(operation_logger, app, label=None, args=None, no_remove_on_failu
             error = m18n.n('app_install_script_failed')
             logger.exception(m18n.n("app_install_failed", app=app_id, error=error))
             failure_message_with_debug_instructions = operation_logger.error(error)
+            if msettings.get('interface') != 'api':
+                dump_app_log_extract_for_debugging(operation_logger)
     # Script got manually interrupted ... N.B. : KeyboardInterrupt does not inherit from Exception
     except (KeyboardInterrupt, EOFError):
         error = m18n.n('operation_interrupted')
@@ -1118,6 +1122,33 @@ def app_install(operation_logger, app, label=None, args=None, no_remove_on_failu
     hook_callback('post_app_install', args=args_list, env=env_dict)
 
 
+def dump_app_log_extract_for_debugging(operation_logger):
+
+    with open(operation_logger.log_path, "r") as f:
+        lines = f.readlines()
+
+    lines_to_display = []
+    for line in lines:
+
+        if not ": " in line.strip():
+            continue
+
+        # A line typically looks like
+        # 2019-10-19 16:10:27,611: DEBUG - + mysql -u piwigo --password=********** -B piwigo
+        # And we just want the part starting by "DEBUG - "
+        line = line.strip().split(": ", 1)[1]
+        lines_to_display.append(line)
+
+        if line.endswith("+ ynh_exit_properly"):
+            break
+        elif len(lines_to_display) > 20:
+            lines_to_display.pop(0)
+
+    logger.warning("Here's an extract of the logs before the crash. It might help debugging the error:")
+    for line in lines_to_display:
+        logger.info(line)
+
+
 def _migrate_legacy_permissions(app):
 
     from yunohost.permission import user_permission_list, user_permission_update

src/yunohost/backup.py

@@ -36,14 +36,14 @@ from datetime import datetime
 from glob import glob
 from collections import OrderedDict
 
-from moulinette import msignals, m18n
+from moulinette import msignals, m18n, msettings
 from yunohost.utils.error import YunohostError
 from moulinette.utils import filesystem
 from moulinette.utils.log import getActionLogger
 from moulinette.utils.filesystem import read_file, mkdir, write_to_yaml, read_yaml
 
 from yunohost.app import (
-    app_info, _is_installed, _parse_app_instance_name, _patch_php5
+    app_info, _is_installed, _parse_app_instance_name, _patch_php5, dump_app_log_extract_for_debugging
 )
 from yunohost.hook import (
     hook_list, hook_info, hook_callback, hook_exec, CUSTOM_HOOK_FOLDER
@@ -1399,6 +1399,9 @@ class RestoreManager():
             logger.exception(msg)
             operation_logger.error(msg)
 
+            if msettings.get('interface') != 'api':
+                dump_app_log_extract_for_debugging(operation_logger)
+
             self.targets.set_result("apps", app_instance_name, "Error")
 
             remove_script = os.path.join(app_scripts_in_archive, 'remove')