Yourls: Racing condition results in error message as response but still http 200

[schapsl]

Describe the bug
When putting load on yourls, it can happen that it tries to insert the same key again. This results in a db error, which message is send as respone with http 200.

To Reproduce

Put load on service with parallel curl commands;

for i in {1..5}; do curl -w'\n' -sSiv --raw "https://<host>/yourls-api.php?action=shorturl&format=simple&signature=<sig>&url=http%3A%2F%2F<url>" & done

You might want to increase the counter and/or try it several times.

Expected behavior

Catch the db exception, because it could be handled, either

• retry or
• respond with http status 500 (Internal server error) or maybe 503 (service unavailable)

Catch all unkown exceptions and respond with 500, log error.

Actual behavior

Response is the db error message with HTTP/1.1 200 OK

Output

HTTP/1.1 200 OK

 <br />
<b>Fatal error</b>:  Uncaught PDOException: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '1hwza' for key 'PRIMARY' in 
/var/www/html/includes/vendor/aura/sql/src/ExtendedPdo.php:748
Stack trace:
#0 /var/www/html/includes/vendor/aura/sql/src/ExtendedPdo.php(748): PDOStatement-&gt;execute()
#1 /var/www/html/includes/vendor/aura/sql/src/ExtendedPdo.php(306): Aura\Sql\ExtendedPdo-&gt;perform('INSERT INTO `yo...', Array)
#2 /var/www/html/includes/functions.php(161): Aura\Sql\ExtendedPdo-&gt;fetchAffected('INSERT INTO `yo...', Array)
#3 /var/www/html/includes/functions.php(278): yourls_insert_link_in_db('http://www.XXXX...', '1hwza', 'http://www.qweq...')
#4 /var/www/html/includes/functions-api.php(21): yourls_add_new_link('http://www.XXXX...', '1hwza', 'http://www.XXXX...')
#5 /var/www/html/includes/functions-plugins.php(150): yourls_api_action_shorturl(false)
#6 /var/www/html/yourls-api.php(35): yourls_apply_filter('api_action_shor...', false)
#7 {main}
  thrown in <b>/var/www/html/includes/vendor/aura/sql/src/ExtendedPdo.php</b> on line <b>748</b><br />

Versions
1.7.2 on Google Cloud Kubernetes

[ozh]

Yeah, more or less know problem. Might want to check API Concurrency Plugin. Very open to tested patch improving things.

[tantweiler]

This issue seems to pop up with v1.7.3 only. All versions before v1.7.3 don't have this issue. In my point of view definitely a bug.

[tantweiler]

@ozh btw why did you close the issue when this bug is known and still open?

[stefangrund]

Yep, same problem for me running 1.7.4, while everything works fine with 1.7.2, like @tantweiler said.