forgejo-docs/docs/admin/logging-documentation.md

title	license	origin_url
Logging Configuration	Apache-2.0	e865de1e9d/docs/content/administration/logging-config.en-us.md

The logging configuration of Forgejo mainly consists of 3 types of components:

• The [log] section for general configuration
• [log.<mode-name>] sections for the configuration of different log writers to output logs, aka: "writer mode", the mode name is also used as "writer name".
• The [log] section can also contain sub-logger configurations following the key schema logger.<logger-name>.<CONFIG-KEY>

There is a fully functional log output by default, so it is not necessary to define one.

The [log] section

Configuration of logging facilities in Forgejo happen in the [log] section and its subsections.

In the top level [log] section the following configurations can be placed:

• ROOT_PATH: (Default: %(GITEA_WORK_DIR)/log): Base path for log files
• MODE: (Default: console) List of log outputs to use for the Default logger.
• LEVEL: (Default: Info) Least severe log events to persist, case-insensitive. Possible values are: Trace, Debug, Info, Warn, Error, Fatal.
• STACKTRACE_LEVEL: (Default: None) For this and more severe events the stacktrace will be printed upon getting logged.

And it can contain the following sub-loggers:

• logger.default.MODE: (Default: ,): List of log outputs to use for the default logger.
• logger.router.MODE: (Default: ,): List of log outputs to use for the Router logger.
• logger.access.MODE: (Default: <empty>) List of log outputs to use for the Access logger. By default, the access logger is disabled.
• logger.xorm.MODE: (Default: ,) List of log outputs to use for the XORM logger.

Setting a comma (,) to sub-logger's mode means making it use the default global MODE.

Quick samples

Default (empty) Configuration

The empty configuration is equivalent to default:

[log]
ROOT_PATH = %(GITEA_WORK_DIR)/log
MODE = console
LEVEL = Info
STACKTRACE_LEVEL = None
logger.default.MODE = ,
logger.router.MODE = ,
logger.xorm.MODE = ,
logger.access.MODE =

; this is the config options of "console" mode (used by MODE=console above)
[log.console]
MODE = console
FLAGS = stdflags
PREFIX =
COLORIZE = true

This is equivalent to sending all logs to the console, with default Golang log being sent to the console log too.

This is only a sample, and it is the default, do not need to write it into your configuration file.

Disable Router logs and record some access logs to file

The Router logger is disabled, the access logs (>=Warn) goes into access.log:

[log]
logger.router.MODE =
logger.access.MODE = access-file

[log.access-file]
MODE = file
LEVEL = Warn
FILE_NAME = access.log

Set different log levels for different modes

Default logs (>=Warn) goes into gitea.log, while Error logs goes into file-error.log:

[log]
LEVEL = Warn
MODE = file, file-error

; by default, the "file" mode will record logs to %(log.ROOT_PATH)/gitea.log, so we don't need to set it
; [log.file]
; by default, the MODE (actually it's the output writer of this logger) is taken from the section name, so we don't need to set it either
; MODE = file

[log.file-error]
MODE = file
LEVEL = Error
FILE_NAME = file-error.log

Log outputs (mode and writer)

Forgejo provides the following log output writers:

• console - Log to stdout (or stderr if it is set in the config)
• file - Log to a file
• conn - Log to a socket (network or unix)

Common configuration

Certain configuration is common to all modes of log output:

• MODE is the mode of the log output writer. It will default to the mode name in the ini section. Thus [log.console] will default to MODE = console.
• LEVEL is the lowest level that this output will log.
• STACKTRACE_LEVEL is the lowest level that this output will print a stacktrace.
• COLORIZE will default to true for console if writing to the terminal (see below), otherwise it will default to false.

EXPRESSION

EXPRESSION represents a regular expression that log events must match to be logged by the output writer. Either the log message, (with colors removed), must match or the longfilename:linenumber:functionname must match. NB: the whole message or string doesn't need to completely match.

Please note this expression will be run in the writer's goroutine but not the logging event goroutine.

FLAGS

FLAGS represents the preceding logging context information that is printed before each message. It is a comma-separated string set. The order of values does not matter.

It defaults to stdflags (= date,time,medfile,shortfuncname,levelinitial). Except for the access log which defaults to none

Possible values are:

• none or , - No flags.
• date - the date in the local time zone: 2009/01/23.
• time - the time in the local time zone: 01:23:23.
• microseconds - microsecond resolution: 01:23:23.123123. Assumes time.
• longfile - full file name and line number: /a/b/c/d.go:23.
• shortfile - final file name element and line number: d.go:23.
• funcname - function name of the caller: runtime.Caller().
• shortfuncname - last part of the function name. Overrides funcname.
• utc - if date or time is set, use UTC rather than the local time zone.
• levelinitial - initial character of the provided level in brackets eg. [I] for info.
• level - level in brackets [INFO].
• levelprefix - journald-style log level prefix, such as <5> for "info".
• gopid - the Goroutine-PID of the context.
• medfile - last 20 characters of the filename - equivalent to shortfile,longfile.
• stdflags - equivalent to date,time,medfile,shortfuncname,levelinitial.
• journaldflags - equivalent to levelprefix.

Console mode

In this mode the logger will forward log messages to the stdout and stderr streams attached to the Forgejo process.

For loggers in console mode, COLORIZE will default to true when appropriate:

• not on Windows, if the output is connected to a tty;
• on Windows, if the output is connected to either a Windows terminal that can be switched into ANSI mode (Windows 10+), or a Cygwin/MSYS terminal.

Settings:

• STDERR: false: Whether the logger should print to stderr instead of stdout.

journald mode

As an extension to the console mode, if Forgejo detects that stdout and/or stderr are connected to systemd-journald (which will happen automatically when Forgejo is running under systemd), the defaults will change:

• STDERR will default to true if stderr is connected to systemd-journald;
• FLAGS will default to journaldflags if the chosen stream is connected to systemd-journald.

When FLAGS = journaldflags is used, instead of decorating log entries with color or a textual representation of severity (e.g. [INFO] or [ERROR]), Forgejo will annotate each log entry with a machine-readable log level prefix that is captured by journald, enabling native filtering capabilities (e.g. run journalctl -u forgejo -p err to only show errors or worse).

In short, if Forgejo is running under systemd, it is recommended to leave the logging configuration at their defaults, which will use MODE = console and adjust formatting to reduce clutter and enable native log level filtering.

File mode

In this mode the logger will save log messages to a file.

Settings:

• FILE_NAME: The file to write the log events to, relative to ROOT_PATH, Default to %(ROOT_PATH)/gitea.log. Exception: access log will default to %(ROOT_PATH)/access.log.
• MAX_SIZE_SHIFT: 28: Maximum size shift of a single file. 28 represents 256Mb. For details see below.
• LOG_ROTATE true: Whether to rotate the log files. If false, log files will always be appended.
• DAILY_ROTATE: true: Whether to rotate logs daily.
• MAX_DAYS: 7: Delete rotated log files after this number of days.
• COMPRESS: true: Whether to compress old log files by default with gzip.
• COMPRESSION_LEVEL: -1: Compression level. For details see below.

MAX_SIZE_SHIFT defines the maximum size of a file by left shifting 1 the given number of times (1 << x).

The useful values of COMPRESSION_LEVEL are from 1 to (and including) 9, where higher numbers mean better compression. Beware that better compression might come with higher resource usage. Must be preceded with a - sign.

Conn mode

In this mode the logger will send log messages over a network socket.

Settings:

• ADDR: :7020: Sets the address to connect to.
• PROTOCOL: tcp: Set the protocol, either "tcp", "unix" or "udp".
• RECONNECT: false: Try to reconnect when connection is lost.
• RECONNECT_ON_MSG: false: Reconnect host for every single message.

The "Router" logger

The Router logger logs the following message types when Forgejo's route handlers work:

• started messages will be logged at TRACE level
• polling/completed routers will be logged at INFO. Exception: "/assets" static resource requests are also logged at TRACE.
• slow routers will be logged at WARN
• failed routers will be logged at WARN

The "XORM" logger

To make XORM outputs SQL logs, the LOG_SQL in [database] section should also be set to true.

The "Access" logger

The Access logger provides a NCSA Common Log compliant log format. It's highly configurable but caution should be taken when changing its template. The main benefit of this logger is that Forgejo can now log accesses in a standard log format so standard tools may be used.

You can enable this logger using logger.access.MODE = ....

If desired the format of the Access logger can be changed by changing the value of the ACCESS_LOG_TEMPLATE.

Please note, the access logger will log at INFO level, setting the LEVEL of this logger to WARN or above will result in no access logs.

The ACCESS_LOG_TEMPLATE

This value represents a go template. Its default value is

{{.Ctx.RemoteHost}} - {{.Identity}} {{.Start.Format "[02/Jan/2006:15:04:05 -0700]" }} "{{.Ctx.Req.Method}} {{.Ctx.Req.URL.RequestURI}} {{.Ctx.Req.Proto}}" {{.ResponseWriter.Status}} {{.ResponseWriter.Size}} "{{.Ctx.Req.Referer}}" "{{.Ctx.Req.UserAgent}}"`

The template is passed following options:

• Ctx is the context.Context
• Identity is the SignedUserName or "-" if the user is not logged in
• Start is the start time of the request
• ResponseWriter is the http.ResponseWriter

Caution must be taken when changing this template as it runs outside of the standard panic recovery trap. The template should also be as simple as it runs for every request.

Releasing-and-Reopening, Pausing and Resuming logging

If you are running on Unix you may wish to release-and-reopen logs in order to use logrotate or other tools. It is possible force Forgejo to release and reopen it's logging files and connections by sending SIGUSR1 to the running process, or running forgejo manager logging release-and-reopen.

Alternatively, you may wish to pause and resume logging - this can be accomplished through the use of the forgejo manager logging pause and forgejo manager logging resume commands. Please note that whilst logging is paused log events below INFO level will not be stored and only a limited number of events will be stored. Logging may block, albeit temporarily, slowing Forgejo considerably whilst paused - therefore it is recommended that pausing only done for a very short period of time.

Adding and removing logging whilst Forgejo is running

It is possible to add and remove logging whilst Forgejo is running using the forgejo manager logging add and remove subcommands. This functionality can only adjust running log systems and cannot be used to start the access or router loggers if they were not already initialized. If you wish to start these systems you are advised to adjust the app.ini and (gracefully) restart the Forgejo service.

The main intention of these commands is to easily add a temporary logger to investigate problems on running systems where a restart may cause the issue to disappear.

Using logrotate instead of built-in log rotation

Forgejo includes built-in log rotation, which should be enough for most deployments. However, if you instead want to use the logrotate utility:

• Disable built-in log rotation by setting LOG_ROTATE to false in your app.ini.
• Install logrotate.
• Configure logrotate to match your deployment requirements, see man 8 logrotate for configuration syntax details. In the postrotate/endscript block send Forgejo a USR1 signal via kill -USR1 or kill -10 to the forgejo process itself, or run forgejo manager logging release-and-reopen (with the appropriate environment). Ensure that your configurations apply to all files emitted by Forgejo loggers as described in the above sections.
• Always do logrotate /etc/logrotate.conf --debug to test your configurations.
• If you are using docker and are running from outside the container you can use docker exec -u $OS_USER $CONTAINER_NAME sh -c 'forgejo manager logging release-and-reopen' or docker exec $CONTAINER_NAME sh -c '/bin/s6-svc -1 /etc/s6/gitea/' or send USR1 directly to the Forgejo process itself.

The next logrotate jobs will include your configurations, so no restart is needed. You can also immediately reload logrotate with logrotate /etc/logrotate.conf --force.