phpsymfonymonologgraylog2gelf

Graylog / Symfony2 / Gelf: How to configure logger to ignore errors?


I'm trying to stream logs from a symfony 2 app to a graylog 2 server using the gelf format.

My monolog configuration looks as follows:

monolog:
    handlers:
          # --- 8< ---
          # ...
          # --- >8 --- 
          graylog:
              type: gelf
              publisher:
                  hostname: my-graylog-server.com
                  port: 12201
              level: debug
              formatter: app.gelf_formatter

When the graylog server is not available, I get (understandably) a connection refused error

[2017-07-28 16:03:25] app.ERROR: Failed to write to socket: fwrite(): send of 153 bytes failed with errno=111 Connection refused (8) [] []

which results in an internal server error (500 response code to the request causing the log).

(See also this question: Prevent Internal Server Error with Symfony 2 / Monolog on failed gelf connection)

gelf-php provides an IngoreErrorTransportLogger, which seems to be build for this exact purpose.

How can I configure this in Symfony's monolog config?


Solution

  • It turns out that Symfony has WhatFailureGroup handler wrapper a handler which ignores errors from the logs of all logging handlers that it wraps.

    Our config now looks like this, it just drops errors during logging (probably not ideal, but better than failing outright due to an error during logging).

    monolog:
        handlers:
              main:
                  type:         fingers_crossed
                  action_level: warning
                  handler:      grouped
              grouped:
                  type:         whatfailuregroup
                  members:      [file, graylog]
              file:
                  type:         stream
                  path:         "%kernel.logs_dir%/%kernel.environment%.log"
                  level:        debug
              graylog:
                  type: gelf
                  publisher:
                      hostname: my-graylog-server.com
                      port: 12201
                  level: debug
                  formatter: app.gelf_formatter
    

    Essentially we replaced type: group with type: whatfailuregroup.