3.6 KiB
| title |
|---|
| log (Caddyfile directive) |
log
Enables and configures HTTP request logging (also known as access logs).
Syntax
log {
output <writer_module> ...
format <encoder_module> ...
level <level>
}
- output configures a where to write the logs to. See Output modules below. Default:
stderr - format describes how to encode, or format, the logs. See Format modules below. Default
console - level is the minimum entry level to log. Default:
INFO
Output modules
The output subdirective lets you customize where logs get written. It appears within a log block.
stderr
Standard error (console, default).
output stderr
stdout
Standard output (console).
output stdout
discard
No output.
output discard
file
A file. By default, log files are rotated ("rolled") to prevent disk space exhaustion.
output file <filename> {
roll_disabled
roll_size <size>
roll_keep <num>
roll_keep_for <days>
}
- <filename> is the path to the log file.
- roll_disabled disables log rolling. This can lead to disk space depletion, so only use this if your log files are maintained some other way.
- roll_size is the size at which to roll the log file. Default:
100MiB - roll_keep is how many log files to keep before deleting the oldest ones. Default:
10 - roll_keep_for is how long to keep rolled files. Default: 90 days
net
A network socket.
output net <address>
- <address> is the address to write logs to.
Format modules
The format subdirective lets you customize how logs get encoded (formatted). It appears within a log block.
In addition to the syntax for each individual encoder, these common properties can be set on most encoders:
{
message_key <key>
level_key <key>
time_key <key>
name_key <key>
caller_key <key>
stacktrace_key <key>
line_ending <char>
time_format <format>
level_format <format>
}
- message_key The key for the message field of the log entry. Default:
message - level_key The key for the level field of the log entry. Default:
level - time_key The key for the time field of the log entry. Default:
time - name_key The key for the name field of the log entry (i.e. the name of the logger itself). Default:
name - caller_key The key for the caller field of the log entry.
- stacktrace_key The key for the stacktrace field of the log entry.
- line_ending The line endings to use.
- time_format The format for timestamps.
- level_format The format for levels.
console
The console encoder formats the log entry for human readability while preserving some structure.
output console
json
Formats each log entry as a JSON object.
output json
logfmt
Formats each log entry as logfmt.
output logfmt
single_field
Writes only a single field from the structure log entry. Useful if one of the fields has all the information you need.
output single_field <field_name>
- <field_name> is the name of the field whose value to use as the log entry.
Examples
Enable access logging (to the console):
log
Write logs to a file (with log rolling, which is enabled by default):
log {
output file /var/log/access.log
}
Customize log rolling:
log {
output file /var/log/access.log {
roll_size 1gb
roll_keep 5
}
}
Use common log format (deprecated, but can be useful for older setups):
log {
format single_field common_log
}