api: Keep stdout and stderr separate

This prevents a rare parse error in case PHP emits a warning, which would mangle
the (also produced) JSON output otherwise.

Signed-off-by: Martin Lehmann <[email protected]>

nextcloud_news_updater/api/cli.py

@@ -1,4 +1,4 @@
-from subprocess import check_output, CalledProcessError, STDOUT
+from subprocess import check_output, CalledProcessError, PIPE
 from typing import List, Any
 
 from nextcloud_news_updater.api.api import Api, Feed
@@ -9,7 +9,7 @@
 
 class Cli:
     def run(self, commands: List[str]) -> bytes:
-        return check_output(commands, stderr=STDOUT)
+        return check_output(commands, stderr=PIPE)
 
 
 class CliApi(Api):
@@ -81,7 +81,7 @@ def run_command(self, command: List[str]) -> None:
             self.logger.error("Command '%s' returned %d with output: '%s'" %
                               (' '. join(command),
                                e.returncode,
-                               e.output.decode().strip()))
+                               e.stderr.decode().strip()))
 
     def update_feed(self, feed: Feed) -> None:
         command = self.api.update_feed_command + [str(feed.feed_id),