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date | title | slug | weight | toc | draft | menu |
---|---|---|---|---|---|---|
2019-04-02T17:06:00+01:00 | Advanced: Logging Configuration | logging-configuration | 55 | true | false | [{sidebar [{parent advanced} {name Logging Configuration} {weight 55} {identifier logging-configuration}]}] |
Logging Configuration
The logging framework has been revamped in Gitea 1.9.0.
{{< toc >}}
Log Groups
The fundamental thing to be aware of in Gitea is that there are several log groups:
- The "Default" logger
- The Macaron logger
- The Router logger
- The Access logger
- The XORM logger
There is also the go log logger.
The go log logger
Go provides its own extremely basic logger in the log
package,
however, this is not sufficient for our purposes as it does not provide
a way of logging at multiple levels, nor does it provide a good way of
controlling where these logs are logged except through setting of a
writer.
We have therefore redirected this logger to our Default logger, and we will log anything that is logged using the go logger at the INFO level.
The "Default" logger
Calls to log.Info
, log.Debug
, log.Error
etc. from the code.gitea.io/gitea/modules/log
package will log to this logger.
You can configure the outputs of this logger by setting the MODE
value in the [log]
section of the configuration.
Each output sublogger is configured in a separate [log.sublogger.default]
which inherits from the sublogger [log.sublogger]
section and from the
generic [log]
section, but there are certain default values. These will
not be inherited from the [log]
section:
FLAGS
isstdflags
(Equal todate,time,medfile,shortfuncname,levelinitial
)FILE_NAME
will default to%(ROOT_PATH)/gitea.log
EXPRESSION
will default to""
PREFIX
will default to""
The provider type of the sublogger can be set using the MODE
value in
its subsection, but will default to the name. This allows you to have
multiple subloggers that will log to files.
The "Macaron" logger
By default Macaron will log to its own go log
instance. This writes
to os.Stdout
. You can redirect this log to a Gitea configurable logger
through setting the REDIRECT_MACARON_LOG
setting in the [log]
section which you can configure the outputs of by setting the MACARON
value in the [log]
section of the configuration. MACARON
defaults
to file
if unset.
Please note, the macaron logger will log at INFO
level, setting the
LEVEL
of this logger to WARN
or above will result in no macaron logs.
Each output sublogger for this logger is configured in
[log.sublogger.macaron]
sections. There are certain default values
which will not be inherited from the [log]
or relevant
[log.sublogger]
sections:
FLAGS
isstdflags
(Equal todate,time,medfile,shortfuncname,levelinitial
)FILE_NAME
will default to%(ROOT_PATH)/macaron.log
EXPRESSION
will default to""
PREFIX
will default to""
NB: You can redirect the macaron logger to send its events to the gitea
log using the value: MACARON = ,
The "Router" logger
There are two types of Router log. By default Macaron send its own
router log which will be directed to Macaron's go log
, however if you
REDIRECT_MACARON_LOG
you will enable Gitea's router log. You can
disable both types of Router log by setting DISABLE_ROUTER_LOG
.
If you enable the redirect, you can configure the outputs of this
router log by setting the ROUTER
value in the [log]
section of the
configuration. ROUTER
will default to console
if unset. The Gitea
Router logs the same data as the Macaron log but has slightly different
coloring. It logs at the Info
level by default, but this can be
changed if desired by setting the ROUTER_LOG_LEVEL
value.
Please note, setting the LEVEL
of this logger to a level above
ROUTER_LOG_LEVEL
will result in no router logs.
Each output sublogger for this logger is configured in
[log.sublogger.router]
sections. There are certain default values
which will not be inherited from the [log]
or relevant
[log.sublogger]
sections:
FILE_NAME
will default to%(ROOT_PATH)/router.log
FLAGS
defaults todate,time
EXPRESSION
will default to""
PREFIX
will default to""
NB: You can redirect the router logger to send its events to the Gitea
log using the value: ROUTER = ,
The "Access" logger
The Access logger is a new logger for version 1.9. It 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 Gitea can now log accesses in a standard log format so standard tools may be used.
You can enable this logger using ENABLE_ACCESS_LOG
. Its outputs are
configured by setting the ACCESS
value in the [log]
section of the
configuration. ACCESS
defaults to file
if unset.
Each output sublogger for this logger is configured in
[log.sublogger.access]
sections. There are certain default values
which will not be inherited from the [log]
or relevant
[log.sublogger]
sections:
FILE_NAME
will default to%(ROOT_PATH)/access.log
FLAGS
defaults to `` or NoneEXPRESSION
will default to""
PREFIX
will default to""
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.
NB: You can redirect the access logger to send its events to the Gitea
log using the value: ACCESS = ,
The ACCESS_LOG_TEMPLATE
This value represent a go template. It's default value is:
{{.Ctx.RemoteAddr}} - {{.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 themacaron.Context
Identity
is theSignedUserName
or"-"
if the user is not logged inStart
is the start time of the requestResponseWriter
is themacaron.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.
The "XORM" logger
The XORM logger is a long-standing logger that exists to collect XORM
log events. It is enabled by default but can be switched off by setting
ENABLE_XORM_LOG
to false
in the [log]
section. Its outputs are
configured by setting the XORM
value in the [log]
section of the
configuration. XORM
defaults to ,
if unset, meaning it is redirected
to the main Gitea log.
XORM will log SQL events by default. This can be changed by setting
the LOG_SQL
value to false
in the [database]
section.
Each output sublogger for this logger is configured in
[log.sublogger.xorm]
sections. There are certain default values
which will not be inherited from the [log]
or relevant
[log.sublogger]
sections:
FILE_NAME
will default to%(ROOT_PATH)/xorm.log
FLAGS
defaults todate,time
EXPRESSION
will default to""
PREFIX
will default to""
Log outputs
Gitea provides 4 possible log outputs:
console
- Log toos.Stdout
oros.Stderr
file
- Log to a fileconn
- Log to a keep-alive TCP connectionsmtp
- Log via email
Certain configuration is common to all modes of log output:
LEVEL
is the lowest level that this output will log. This value is inherited from[log]
and in the case of the non-default loggers from[log.sublogger]
.STACKTRACE_LEVEL
is the lowest level that this output will print a stacktrace. This value is inherited.MODE
is the mode of the log output. It will default to the sublogger name. Thus[log.console.macaron]
will default toMODE = console
.COLORIZE
will default totrue
forconsole
as described, otherwise it will default tofalse
.
Non-inherited default values
There are several values which are not inherited as described above but
rather default to those specific to type of logger, these are:
EXPRESSION
, FLAGS
, PREFIX
and FILE_NAME
.
EXPRESSION
EXPRESSION
represents a regular expression that log events must match to be logged by the sublogger. 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 sublogger's goroutine not the logging event subroutine. Therefore it can be complicated.
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.
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. Overridesfuncname
.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
- Provided level in brackets[INFO]
medfile
- Last 20 characters of the filename - equivalent toshortfile,longfile
.stdflags
- Equivalent todate,time,medfile,shortfuncname,levelinitial
Console mode
For loggers in console mode, COLORIZE
will default to true
if not
on windows, or the windows terminal can be set into ANSI mode or is a
cygwin or Msys pipe.
If STDERR
is set to true
the logger will use os.Stderr
instead of
os.Stdout
.
File mode
The FILE_NAME
defaults as described above. If set it will be relative
to the provided ROOT_PATH
in the master [log]
section.
Other values:
LOG_ROTATE
: true: Rotate the log files.MAX_SIZE_SHIFT
: 28: Maximum size shift of a single file, 28 represents 256Mb.DAILY_ROTATE
: true: Rotate logs daily.MAX_DAYS
: 7: Delete the log file after n daysCOMPRESS
: true: Compress old log files by default with gzipCOMPRESSION_LEVEL
: -1: Compression level
Conn mode
RECONNECT_ON_MSG
: false: Reconnect host for every single message.RECONNECT
: false: Try to reconnect when connection is lost.PROTOCOL
: tcp: Set the protocol, either "tcp", "unix" or "udp".ADDR
: :7020: Sets the address to connect to.
SMTP mode
It is not recommended to use this logger to send general logging
messages. However, you could perhaps set this logger to work on FATAL
.
USER
: User email address to send from.PASSWD
: Password for the smtp server.HOST
: 127.0.0.1:25: The SMTP host to connect to.RECEIVERS
: Email addresses to send to.SUBJECT
: Diagnostic message from Gitea
Debugging problems
When submitting logs in Gitea issues it is often helpful to submit merged logs obtained by either by redirecting the console log to a file or copying and pasting it. To that end it is recommended to set your logging to:
[database]
LOG_SQL = false ; SQL logs are rarely helpful unless we specifically ask for them
...
[log]
MODE = console
LEVEL = debug ; please set the level to debug when we are debugging a problem
REDIRECT_MACARON_LOG = true
MACARON = console
ROUTER = console
COLORIZE = false ; this can be true if you can strip out the ansi coloring
Sometimes it will be helpful get some specific TRACE
level logging retricted
to messages that match a specific EXPRESSION
. Adjusting the MODE
in the
[log]
section to MODE = console,traceconsole
to add a new logger output
traceconsole
and then adding its corresponding section would be helpful:
[log.traceconsole] ; traceconsole here is just a name
MODE = console ; this is the output that the traceconsole writes to
LEVEL = trace
EXPRESSION = ; putting a string here will restrict this logger to logging only those messages that match this expression
(It's worth noting that log messages that match the expression at or above debug level will get logged twice so don't worry about that.)
STACKTRACE_LEVEL
should generally be left unconfigured (and hence kept at
none
). There are only very specific occasions when it useful.
Empty Configuration
The empty configuration is equivalent to:
[log]
ROOT_PATH = %(GITEA_WORK_DIR)/log
MODE = console
LEVEL = Info
STACKTRACE_LEVEL = None
REDIRECT_MACARON_LOG = false
ENABLE_ACCESS_LOG = false
ENABLE_XORM_LOG = true
XORM = ,
[log.console]
MODE = console
LEVEL = %(LEVEL)
STACKTRACE_LEVEL = %(STACKTRACE_LEVEL)
FLAGS = stdflags
PREFIX =
COLORIZE = true # Or false if your windows terminal cannot color
This is equivalent to sending all logs to the console, with default go log being sent to the console log too.
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 gitea to release and reopen it's logging files and connections by sending SIGUSR1
to the
running process, or running gitea manager logging release-and-reopen
.
Alternatively, you may wish to pause and resume logging - this can be accomplished through the use of the
gitea manager logging pause
and gitea 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 gitea considerably whilst paused - therefore it is
recommended that pausing only done for a very short period of time.
Adding and removing logging whilst Gitea is running
It is possible to add and remove logging whilst Gitea is running using the gitea manager logging add
and remove
subcommands.
This functionality can only adjust running log systems and cannot be used to start the access, macaron or router loggers if they
were not already initialised. If you wish to start these systems you are advised to adjust the app.ini and (gracefully) restart
the Gitea 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.
Log colorization
Logs to the console will be colorized by default when not running on Windows. Terminal sniffing will occur on Windows and if it is determined that we are running on a terminal capable of color we will colorize.
Further, on *nix it is becoming common to have file logs that are colored by default. Therefore file logs will be colorised by default when not running on Windows.
You can switch on or off colorization by using the COLORIZE
value.
From a development point of view. If you write
log.Info("A %s string", "formatted")
the formatted
part of the log
message will be Bolded on colorized logs.
You can change this by either rendering the formatted string yourself.
Or you can wrap the value in a log.ColoredValue
struct.
The log.ColoredValue
struct contains a pointer to value, a pointer to
string of bytes which should represent a color and second set of reset
bytes. Pointers were chosen to prevent copying of large numbers of
values. There are several helper methods:
log.NewColoredValue
takes a value and 0 or more color attributes that represent the color. If 0 are provided it will default to a cached bold. Note, it is recommended that color bytes constructed from attributes should be cached if this is a commonly used log message.log.NewColoredValuePointer
takes a pointer to a value, and 0 or more color attributes that represent the color.log.NewColoredValueBytes
takes a value and a pointer to an array of bytes representing the color.
These functions will not double wrap a log.ColoredValue
. They will
also set the resetBytes
to the cached resetBytes
.
The colorBytes
and resetBytes
are not exported to prevent
accidental overwriting of internal values.
ColorFormat & ColorFormatted
Structs may implement the log.ColorFormatted
interface by implementing the ColorFormat(fmt.State)
function.
If a log.ColorFormatted
struct is logged with %-v
format, its ColorFormat
will be used instead of the usual %v
. The full fmt.State
will be passed to allow implementers to look at additional flags.
In order to help implementers provide ColorFormat
methods. There is a
log.ColorFprintf(...)
function in the log module that will wrap values in log.ColoredValue
and recognise %-v
.
In general it is recommended not to make the results of this function too verbose to help increase its versatility. Usually this should simply be an ID
:Name
. If you wish to make a more verbose result, it is recommended to use %-+v
as your marker.
Log Spoofing protection
In order to protect the logs from being spoofed with cleverly
constructed messages. Newlines are now prefixed with a tab and control
characters except those used in an ANSI CSI are escaped with a
preceding \
and their octal value.
Creating a new named logger group
Should a developer wish to create a new named logger, NEWONE
. It is
recommended to add an ENABLE_NEWONE_LOG
value to the [log]
section, and to add a new NEWONE
value for the modes.
A function like func newNewOneLogService()
is recommended to manage
construction of the named logger. e.g.
func newNewoneLogService() {
EnableNewoneLog = Cfg.Section("log").Key("ENABLE_NEWONE_LOG").MustBool(false)
Cfg.Section("log").Key("NEWONE").MustString("file") // or console? or "," if you want to send this to default logger by default
if EnableNewoneLog {
options := newDefaultLogOptions()
options.filename = filepath.Join(LogRootPath, "newone.log")
options.flags = "stdflags"
options.bufferLength = Cfg.Section("log").Key("BUFFER_LEN").MustInt64(10000)
generateNamedLogger("newone", options)
}
}
You should then add newOneLogService
to NewServices()
in
modules/setting/setting.go
Using logrotate
instead of built-in log rotation
Gitea 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
tofalse
in yourapp.ini
. - Install
logrotate
. - Configure
logrotate
to match your deployment requirements, seeman 8 logrotate
for configuration syntax details. In thepostrotate/endscript
block send Gitea aUSR1
signal viakill -USR1
orkill -10
, or rungitea manager logging release-and-reopen
(with the appropriate environment). Ensure that your configurations apply to all files emitted by Gitea loggers as described in the above sections. - Always do
logrotate /etc/logrotate.conf --debug
to test your configurations.
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
.