--- name: "bunyan" section: "1" platform: "linux" package: "node-bunyan" version: "2.0.5+~cs4.4.3-2" release: "Debian 12 (Bookworm)" platforms: ["linux"] url: "https://new.carta.tech/bunyan" --- # bunyan(1) filter and pretty-print Bunyan log file content ## NAME **bunyan** - filter and pretty-print Bunyan log file content ## SYNOPSIS **bunyan** \[OPTIONS\] ... \| **bunyan** \[OPTIONS\] **bunyan** \[OPTIONS\] -p PID ## DESCRIPTION "Bunyan" is **a simple and fast a JSON logging library** for node.js services, a one-JSON-object-per-line log format, and **a bunyan** CLI tool for nicely viewing those logs. This man page describes the latter. ### Pretty-printing A bunyan log file is a stream of JSON objects, optionally interspersed with non-JSON log lines. The primary usage of [bunyan(1)](/bunyan/1.md) is to pretty print, for example: - ``` $ bunyan foo.log # or `cat foo.log | bunyan [2012-02-08T22:56:52.856Z] INFO: myservice/123 on example.com: My message extra: multi line [2012-02-08T22:56:54.856Z] ERROR: myservice/123 on example.com: My message ``` - By default the "long" output format is used. Use the **-o FORMAT** option to emit other formats. E.g.: - ``` $ bunyan foo.log -o short 22:56:52.856Z INFO myservice: My message extra: multi line 22:56:54.856Z ERROR myservice: My message ``` - These will color the output if supported in your terminal. See "OUTPUT FORMATS" below. ### Filtering The **bunyan** CLI can also be used to filter a bunyan log. Use **-l LEVEL** to filter by level: - ``` $ bunyan foo.log -l error # show only ´error´ level records [2012-02-08T22:56:54.856Z] ERROR: myservice/123 on example.com: My message ``` - Use **-c COND** to filter on a JavaScript expression returning true on the record data. In the COND code, **this** refers to the record object: - ``` $ bunyan foo.log -c `this.three` # show records with the ´extra´ field [2012-02-08T22:56:52.856Z] INFO: myservice/123 on example.com: My message extra: multi line ``` - ## OPTIONS - **-h**, **--help** Print this help info and exit. - **--version** Print version of this command and exit. - **-q**, **--quiet** Don´t warn if input isn´t valid JSON. Dtrace options (only on dtrace-supporting platforms): - **-p PID**, **-p NAME** Process bunyan:log-\* probes from the process with the given PID. Can be used multiple times, or specify all processes with ´\*´, or a set of processes whose command & args match a pattern with ´-p NAME´. Filtering options: - **-l**, **--level LEVEL** Only show messages at or above the specified level. You can specify level *names* or numeric values. (See ´Log Levels´ below.) - **-c COND**, **--condition COND** Run each log message through the condition and only show those that resolve to a truish value. E.g. **-c ´this.pid == 123´**. - **--strict** Suppress all but legal Bunyan JSON log lines. By default non-JSON, and non-Bunyan lines are passed through. Output options: - **--color** Colorize output. Defaults to try if output stream is a TTY. - **--no-color** Force no coloring (e.g. terminal doesn´t support it) - **-o FORMAT**, **--output FORMAT** Specify an output format. One of **long** (the default), **short**, **json**, **json-N**, **bunyan** (the native bunyan 0-indent JSON output) or **inspect**. - **-j** Shortcut for **-o json**. - **-L**, **--time local** Display the time field in *local* time, rather than the default UTC time. ## LOG LEVELS In Bunyan log records, then **level** field is a number. For the **-l\|--level** argument the level **names** are supported as shortcuts. In **-c\|--condition** scripts, uppercase symbols like "DEBUG" are defined for convenience. - ``` Level Name Level Number Symbol in COND Scripts trace 10 TRACE debug 20 DEBUG info 30 INFO warn 40 WARN error 50 ERROR fatal 60 FATAL ``` - ## OUTPUT FORMATS ``` FORMAT NAME DESCRIPTION long (default) The default output. Long form. Colored and "pretty". ´req´ and ´res´ and ´err´ fields are rendered specially as an HTTP request, HTTP response and exception stack trace, respectively. For backward compat, the name "paul" also works for this. short Like the default output, but more concise. Some typically redundant fields are ellided. json JSON output, 2-space indentation. json-N JSON output, N-space indentation, e.g. "json-4" bunyan Alias for "json-0", the Bunyan "native" format. inspect Node.js `util.inspect` output. ``` ## DTRACE SUPPORT On systems that support DTrace (e.g., MacOS, FreeBSD, illumos derivatives like SmartOS and OmniOS), Bunyan will create a DTrace provider (**bunyan**) that makes available the following probes: - ``` log-trace log-debug log-info log-warn log-error log-fatal ``` - Each of these probes has a single argument: the string that would be written to the log. Note that when a probe is enabled, it will fire whenever the corresponding function is called, even if the level of the log message is less than that of any stream. See *https://github.com/trentm/node-bunyan#dtrace-support* for more details and the ´-p PID´ option above for convenience usage. ## ENVIRONMENT - **BUNYAN\_NO\_COLOR** Set to a non-empty value to force no output coloring. See ´--no-color´. ## PROJECT & BUGS **bunyan** is written in JavaScript and requires node.js (**node**). The project lives at *https://github.com/trentm/node-bunyan* and is published to npm as "bunyan". - • README, Install notes: *https://github.com/trentm/node-bunyan#readme* - • Report bugs to *https://github.com/trentm/node-bunyan/issues*. - • See the full changelog at: *https://github.com/trentm/node-bunyan/blob/master/CHANGES.md* - ## LICENSE MIT License (see *https://github.com/trentm/node-bunyan/blob/master/LICENSE.txt*) ## COPYRIGHT node-bunyan is Copyright (c) 2012 Joyent, Inc. Copyright (c) 2012 Trent Mick. All rights reserved.