logging - Why, What & How We Log Description The npm CLI has various mechanisms for showing different levels of information back to end-users for certain commands, configurations & environments. Setting Log File Location All logs are written to a debug log, with the path to that file printed if the execution of a command fails. The default location of the logs directory is a directory named _logs inside the npm cache. This can be changed with the logs-dir config option. Log files will be removed from the logs-dir when the number of log files exceeds logs-max, with the oldest logs being deleted first. To turn off logs completely set --logs-max=0. Setting Log Levels loglevel loglevel is a global argument/config that can be set to determine the type of information to be displayed. The default value of loglevel is "notice" but there are several lev- els/types of logs available, including: o "silent" o "error" o "warn" o "notice" o "http" o "timing" o "info" o "verbose" o "silly" All logs pertaining to a level proceeding the current setting will be shown. Aliases The log levels listed above have various corresponding aliases, includ- ing: o -d: --loglevel info o --dd: --loglevel verbose o --verbose: --loglevel verbose o --ddd: --loglevel silly o -q: --loglevel warn o --quiet: --loglevel warn o -s: --loglevel silent o --silent: --loglevel silent foreground-scripts The npm CLI began hiding the output of lifecycle scripts for npm install as of v7. Notably, this means you will not see logs/output from packages that may be using "install scripts" to display information back to you or from your own project's scripts defined in package.json. If you'd like to change this behavior & log this output you can set foreground-scripts to true. Timing Information The --timing config can be set which does two things: 1. Always shows the full path to the debug log regardless of command exit status 2. Write timing information to a timing file in the cache or logs-dir This file is a newline delimited list of JSON objects that can be inspected to see timing data for each task in a npm CLI run. Registry Response Headers npm-notice The npm CLI reads from & logs any npm-notice headers that are returned from the configured registry. This mechanism can be used by third-party registries to provide useful information when network-dependent requests occur. This header is not cached, and will not be logged if the request is served from the cache. Logs and Sensitive Information The npm CLI makes a best effort to redact the following from terminal output and log files: o Passwords inside basic auth URLs o npm tokens However, this behavior should not be relied on to keep all possible sensitive information redacted. If you are concerned about secrets in your log file or terminal output, you can use --loglevel=silent and --logs-max=0 to ensure no logs are written to your terminal or filesys- tem. See also o npm help config
Please see following description for synopsis
LOGGING(7) LOGGING(7)
NAME
Logging - Why, What & How We Log
Description
The npm CLI has various mechanisms for showing different levels of
information back to end-users for certain commands, configurations &
environments.
Setting Log File Location
All logs are written to a debug log, with the path to that file printed
if the execution of a command fails.
The default location of the logs directory is a directory named _logs
inside the npm cache. This can be changed with the logs-dir config
option.
Log files will be removed from the logs-dir when the number of log
files exceeds logs-max, with the oldest logs being deleted first.
To turn off logs completely set --logs-max=0.
Setting Log Levels
loglevel
loglevel is a global argument/config that can be set to determine the
type of information to be displayed.
The default value of loglevel is "notice" but there are several lev-
els/types of logs available, including:
o "silent"
o "error"
o "warn"
o "notice"
o "http"
o "timing"
o "info"
o "verbose"
o "silly"
All logs pertaining to a level proceeding the current setting will be
shown.
Aliases
The log levels listed above have various corresponding aliases, includ-
ing:
o -d: --loglevel info
o --dd: --loglevel verbose
o --verbose: --loglevel verbose
o --ddd: --loglevel silly
o -q: --loglevel warn
o --quiet: --loglevel warn
o -s: --loglevel silent
o --silent: --loglevel silent
foreground-scripts
The npm CLI began hiding the output of lifecycle scripts for npm
install as of v7. Notably, this means you will not see logs/output from
packages that may be using "install scripts" to display information
back to you or from your own project's scripts defined in package.json.
If you'd like to change this behavior & log this output you can set
foreground-scripts to true.
Timing Information
The --timing config can be set which does two things:
1. Always shows the full path to the debug log regardless of command
exit status
2. Write timing information to a timing file in the cache or logs-dir
This file is a newline delimited list of JSON objects that can be
inspected to see timing data for each task in a npm CLI run.
Registry Response Headers
npm-notice
The npm CLI reads from & logs any npm-notice headers that are returned
from the configured registry. This mechanism can be used by third-party
registries to provide useful information when network-dependent
requests occur.
This header is not cached, and will not be logged if the request is
served from the cache.
Logs and Sensitive Information
The npm CLI makes a best effort to redact the following from terminal
output and log files:
o Passwords inside basic auth URLs
o npm tokens
However, this behavior should not be relied on to keep all possible
sensitive information redacted. If you are concerned about secrets in
your log file or terminal output, you can use --loglevel=silent and
--logs-max=0 to ensure no logs are written to your terminal or filesys-
tem.
See also
o npm help config
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
+---------------+--------------------------+
|ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+---------------+--------------------------+
|Availability | runtime/nodejs/nodejs-18 |
+---------------+--------------------------+
|Stability | Pass-thru volatile |
+---------------+--------------------------+
NOTES
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at
https://github.com/oracle/solaris-userland. The original community
source was downloaded from https://github.com/nodejs/node/ar-
chive/v18.1.0.zip.
Further information about this software can be found on the open source
community website at https://github.com/nodejs/node.
April 2022 LOGGING(7)