rspamc learn fails for already learned messages

[stbuehler]

Classification (Please choose one option):

• Crash/Hang/Data loss
• WebUI/Usability
• Serious bug
• Ordinary bug
• Feature
• Enhancement

Reproducibility (Please choose one option):

• Always
• Sometimes
• Rarely
• Unable
• I didn’t try
• Not applicable

Rspamd version:

1.8.3-1~stretch

Operation system, CPU:

Debian stretch, amd64

Description (Please provide a descriptive summary of the issue):

rspamc learn fails (with exit code 1) for already learned messages (RSPAMD_TASK_FLAG_ALREADY_LEARNED):

# rspamc learn_spam
[...]
Results for file: stdin (0.004 seconds)
HTTP error: 404, <...> has been already learned as spam, ignore it
# echo $?
1

Expected results:

The exit code should be 0; learning didn't change the database because it didn't have to, not because something was wrong.

[c-rosenberg]

d8c8fd5#diff-02786adb24b9071288d5a4f3456bdb64 fixed this.

# apt-cache policy rspamd                                                                                                                                                                     
rspamd:
  Installed: 1.8.3-1~stretch

# rspamc learn_spam file
Results for file: file (0.044 seconds)
error = "<...> has been already learned as spam, ignore it";
filename = "file";
scan_time = 0.044001;

# echo $?
0

And the same when using curl.

[sbergman27]

This is a significant issue for users of, say, Dovecot Antispam. I had to write a wrapper script to check for a return code of 1 and return a 0 in that case. Otherwise, users are unable to move previously seen emails in or out of "Junk", or out of the "unsure" folder. rspamc really needs to return a 0 in the case of previously seen emails.