status-im
/
timbre
mirror of https://github.com/status-im/timbre.git
2
0
Fork 0
Code Issues Projects Releases Wiki Activity

Update README

This commit is contained in:
Peter Taoussanis 2013-11-30 20:19:56 +07:00
parent 16d2345367
commit 29113cc203
2 changed files with 120 additions and 95 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

200
README.md
View File

@ -1,13 +1,14 @@
**[API docs](http://ptaoussanis.github.io/timbre/)** | **[CHANGELOG](https://github.com/ptaoussanis/timbre/blob/master/CHANGELOG.md)** | [contact & contributing](#contact--contribution) | [other Clojure libs](https://www.taoensso.com/clojure-libraries) | [Twitter](https://twitter.com/#!/ptaoussanis) | current [semantic](http://semver.org/) version:
```clojure
[com.taoensso/timbre "2.7.1"] ; Stable
[com.taoensso/timbre "3.0.0-beta1"] ; Development, non-breaking - see CHANGELOG for details
[com.taoensso/timbre "3.0.0-RC1"] ; Non-breaking upgrade - see CHANGELOG for details
```
Appender authors: please see [here](https://github.com/ptaoussanis/timbre/issues/41) about migrating Timbre 2.x appenders to 3.x's recommended style.
# Timbre, a (sane) Clojure logging & profiling library
Logging with Java can be maddeningly, unnecessarily hard. Particularly if all you want is something *simple that works out-the-box*. Timbre is an attempt to bring functional, Clojure-y goodness to all your logging needs. **No XML!**
Logging with Java can be maddeningly, unnecessarily hard. Particularly if all you want is something *simple that works out-the-box*. Timbre brings functional, Clojure-y goodness to all your logging needs. **No XML!**
## What's in the box™?
* Small, uncomplicated **all-Clojure** library.
@ -18,7 +19,7 @@ Logging with Java can be maddeningly, unnecessarily hard. Particularly if all yo
* Sensible built-in appenders including simple **email appender**.
* Tunable **rate limit** and **asynchronous** logging support.
* Robust **namespace filtering**.
* **[tools.logging](https://github.com/clojure/tools.logging) support** (optional).
* [tools.logging](https://github.com/clojure/tools.logging) support (optional, useful when integrating with legacy logging systems).
* Dead-simple, logging-level-aware **logging profiler**.
## Getting started
@ -28,13 +29,13 @@ Logging with Java can be maddeningly, unnecessarily hard. Particularly if all yo
Add the necessary dependency to your [Leiningen](http://leiningen.org/) `project.clj` and use the supplied ns-import helper:
```clojure
[com.taoensso/timbre "2.7.1"] ; project.clj
[com.taoensso/timbre "3.0.0-RC1"] ; project.clj
(ns my-app (:require [taoensso.timbre :as timbre])) ; Your ns
(timbre/refer-timbre) ; Provides useful Timbre aliases in this ns
```
The `refer-timbre` call is a convenience fn and executes:
The `refer-timbre` call is a convenience fn that executes:
```clojure
(require '[taoensso.timbre :as timbre
:refer (log trace debug info warn error fatal report
@ -49,39 +50,16 @@ The `refer-timbre` call is a convenience fn and executes:
By default, Timbre gives you basic print output to `*out*`/`*err*` at a `debug` logging level:
```clojure
(info "This will print")
=> nil
(info "This will print") => nil
%> 2012-May-28 17:26:11:444 +0700 localhost INFO [my-app] - This will print
(spy :info (* 5 4 3 2 1))
=> 120
(spy :info (* 5 4 3 2 1)) => 120
%> 2012-May-28 17:26:14:138 +0700 localhost INFO [my-app] - (* 5 4 3 2 1) 120
(trace "This won't print due to insufficient logging level")
=> nil
(trace "This won't print due to insufficient logging level") => nil
```
There's little overhead for checking logging levels:
```clojure
(time (trace (Thread/sleep 5000)))
%> "Elapsed time: 0.054 msecs"
(time (when false))
%> "Elapsed time: 0.051 msecs"
```
And _no_ overhead when using a compile-time logging level (set `TIMBRE_LOG_LEVEL` environment variable):
```clojure
(time (dotimes [_ 1000000000] (trace (Thread/sleep 5000))))
%> "Elapsed time: 387.159 msecs"
(time (dotimes [_ 1000000000] nil))
%> "Elapsed time: 389.231 msecs"
```
First-argument exceptions generate a stack trace:
First-argument exceptions generate a nicely cleaned-up stack trace using [io.aviso.exception](https://github.com/AvisoNovate/pretty).
```clojure
(info (Exception. "Oh noes") "arg1" "arg2")
@ -94,47 +72,100 @@ java.lang.Exception: Oh noes
### Configuration
Configuring Timbre is a breeze. Let's check out (some of) the defaults:
This is the biggest win over Java logging utilities IMO. Here's `timbre/example-config` (also Timbre's default config):
```clojure
@timbre/config
=>
{:ns-whitelist [] ; Use patterns like "my-app.*"
:ns-blacklist []
(def example-config
"APPENDERS
An appender is a map with keys:
:doc ; (Optional) string.
:min-level ; (Optional) keyword, or nil (no minimum level).
:enabled? ; (Optional).
:async? ; (Optional) dispatch using agent (good for slow appenders).
:rate-limit ; (Optional) [ncalls-limit window-ms].
:fmt-output-opts ; (Optional) extra opts passed to `fmt-output-fn`.
:fn ; (fn [appender-args-map]), with keys described below.
;; Fns to transform/filter appender fn args before dispatching to appenders:
:middleware []
An appender's fn takes a single map with keys:
:level ; Keyword.
:error? ; Is level an 'error' level?.
:throwable ; java.lang.Throwable.
:args ; Raw logging macro args (as given to `info`, etc.).
:message ; Stringified logging macro args, or nil.
:output ; Output of `fmt-output-fn`, used by built-in appenders
; as final, formatted appender output. Appenders may (but
; are not obligated to) use this as their output.
:ap-config ; `shared-appender-config`.
:profile-stats ; From `profile` macro.
:instant ; java.util.Date.
:timestamp ; String generated from :timestamp-pattern, :timestamp-locale.
:hostname ; String.
:ns ; String.
:timestamp-pattern "yyyy-MMM-dd HH:mm:ss ZZ" ; SimpleDateFormat pattern
:timestamp-locale nil ; A Locale object, or nil
MIDDLEWARE
Middleware are fns (applied right-to-left) that transform the map
dispatched to appender fns. If any middleware returns nil, no dispatching
will occur (i.e. the event will be filtered).
:appenders
{:standard-out { <...> }
:spit { <...> }
<...> }
The `example-config` code contains further settings and details.
See also `set-config!`, `merge-config!`, `set-level!`."
:shared-appender-config {}}
{;;; Control log filtering by namespace patterns (e.g. ["my-app.*"]).
;;; Useful for turning off logging in noisy libraries, etc.
:ns-whitelist []
:ns-blacklist []
;; Fns (applied right-to-left) to transform/filter appender fn args.
;; Useful for obfuscating credentials, pattern filtering, etc.
:middleware []
;;; Control :timestamp format
:timestamp-pattern "yyyy-MMM-dd HH:mm:ss ZZ" ; SimpleDateFormat pattern
:timestamp-locale nil ; A Locale object, or nil
;; Output formatter used by built-in appenders. Custom appenders may (but are
;; not required to use) its output (:output). Extra per-appender opts can be
;; supplied as an optional second (map) arg.
:fmt-output-fn
(fn [{:keys [level throwable message timestamp hostname ns]}
;; Any extra appender-specific opts:
& [{:keys [nofonts?] :as appender-fmt-output-opts}]]
;; <timestamp> <hostname> <LEVEL> [<ns>] - <message> <throwable>
(format "%s %s %s [%s] - %s%s"
timestamp hostname (-> level name str/upper-case) ns (or message "")
(or (stacktrace throwable "\n" (when nofonts? {})) "")))
:shared-appender-config {} ; Provided to all appenders via :ap-config key
:appenders
{:standard-out
{:doc "Prints to *out*/*err*. Enabled by default."
:min-level nil :enabled? true :async? false :rate-limit nil
:fn (fn [{:keys [error? output]}]
(binding [*out* (if error? *err* *out*)]
(str-println output)))}
:spit
{:doc "Spits to `(:spit-filename :shared-appender-config)` file."
:min-level nil :enabled? false :async? false :rate-limit nil
:fn (fn [{:keys [ap-config output]}]
(when-let [filename (:spit-filename ap-config)]
(try (spit filename output :append true)
(catch java.io.IOException _))))}}})
```
Easily adjust the current logging level:
A few things to note:
```clojure
(timbre/set-level! :warn)
```
* Appenders are trivial to write & configure - **they're just fns**. It's Timbre's job to dispatch useful args to appenders when appropriate, it's their job to do something interesting with them.
* Being 'just fns', appenders have basically limitless potential: write to your database, send a message over the network, check some other state (e.g. environment config) before making a choice, etc.
And the default timestamp formatting for log messages:
The **logging level** may be set:
* At compile-time: (`TIMBRE_LOG_LEVEL` environment variable).
* Via an atom: `(timbre/set-level! <level>)`. (Usual method).
* Via dynamic thread-level binding: `(timbre/with-log-level <level> ...)`.
```clojure
(timbre/set-config! [:timestamp-pattern] "yyyy-MMM-dd HH:mm:ss ZZ")
(timbre/set-config! [:timestamp-locale] (java.util.Locale/GERMAN))
```
A compile-time level offers _zero-overhead_ performance since it'll cause insufficient logging calls to disappear completely at compile-time. Usually you won't need/want to bother: Timbre offers very decent performance with runtime level checks (~15msecs/10k checks on my Macbook Air).
Filter logging output by namespaces:
```clojure
(timbre/set-config! [:ns-whitelist] ["some.library.core" "my-app.*"])
```
**The source code includes a fully-annotated example config** (as `timbre/example-config`) that gives further details on these and other features.
For common-case ease-of-use, **all logging utils use a global atom for their config**. This is configurable with `timbre/set-config!`, `timbre/merge-config!`. The lower-level `log` and `logf` macros also take an optional first-arg config map for greater flexibility (e.g. **during testing**).
### Built-in appenders
@ -148,7 +179,7 @@ Filter logging output by namespaces:
#### Email ([Postal](https://github.com/drewr/postal)) appender
```clojure
;; [com.draines/postal "1.9.2"] ; Add to project.clj dependencies
;; [com.draines/postal "1.9.2"] ; Add to project.clj deps
;; (:require [taoensso.timbre.appenders (postal :as postal-appender)]) ; Add to ns
(timbre/set-config! [:appenders :postal]
@ -162,32 +193,27 @@ Filter logging output by namespaces:
{:from "me@draines.com" :to "foo@example.com"}}))
```
#### Other included appenders
A number of appenders are included out-the-box for: Android, Carmine (Redis), IRC, sockets, MongoDB, and rotating files.
These are all located in the `taoensso.timbre.appenders.x` namespaces - please see the relevant docstrings for details.
### Custom appenders
Writing a custom appender is (really) very easy:
#### Redis ([Carmine](https://github.com/ptaoussanis/carmine)) appender
```clojure
(timbre/set-config!
[:appenders :my-appender]
{:doc "Hello-world appender"
:min-level :debug
:enabled? true
:async? false
:rate-limit nil
:fn (fn [{:keys [ap-config level throwable output] :as args}]
(when-not (:my-production-mode? ap-config)
(println "Hello world!:" output)))
;; [com.taoensso/carmine "2.4.0"] ; Add to project.clj deps
;; (:require [taoensso.timbre.appenders (:carmine :as car-appender)]) ; Add to ns
(timbre/set-config! [:appenders :carmine] (postal-appenders/make-carmine-appender))
```
And because appender fns are just regular Clojure fns, you have *unlimited power*: write to your database, send a message over the network, check some other state (e.g. environment config) before making a choice, etc.
This gives us an appender that logs serialized entries as follows:
* Logs only the most recent instance of each unique entry.
* Limits the number of entries per level (configurable).
* Sorts entries by date of most recent occurence.
See the `timbre/example-config` annotated code for lots more information on appenders.
Entries are serialized with their raw logging arguments and so well suited for Clojure's usual seq tools (`filter`, `map`, `group-by`, etc.). Even exceptions are maintained and queryable later. A simple query utility is provided: `car-appender/query-entries`.
#### Other included appenders
A number of 3rd-party appenders are included out-the-box for: Android, IRC, sockets, MongoDB, and rotating files. These are all located in the `taoensso.timbre.appenders.x` namespaces - **please see the relevant docstrings for details**.
Thanks to their respective authors! Just give me a shout if you've got an appender you'd like to have added.
## Profiling
@ -208,15 +234,13 @@ Wrap forms that you'd like to profile with the `p` macro and give them a name:
(p :mult (reduce * nums))
(p :div (reduce / nums)))))
(my-fn)
=> 42
(my-fn) => 42
```
The `profile` macro can now be used to log times for any wrapped forms:
```clojure
(profile :info :Arithmetic (dotimes [n 100] (my-fn)))
=> "Done!"
(profile :info :Arithmetic (dotimes [n 100] (my-fn))) => "Done!"
%> 2012-Jul-03 20:46:17 +0700 localhost INFO [my-app] - Profiling my-app/Arithmetic
Name Calls Min Max MAD Mean Total% Total
my-app/slow-sleep 100 2ms 2ms 31μs 2ms 57 231ms

15
src/taoensso/timbre.clj
View File

@ -100,19 +100,20 @@
:fn ; (fn [appender-args-map]), with keys described below.
An appender's fn takes a single map with keys:
:level ; Keyword
:level ; Keyword.
:error? ; Is level an 'error' level?
:throwable ; java.lang.Throwable
:throwable ; java.lang.Throwable.
:args ; Raw logging macro args (as given to `info`, etc.).
:message ; Stringified logging macro args, or nil.
:output ; Output of `fmt-output-fn`, used by built-in appenders
; as final, formatted appender output.
; as final, formatted appender output. Appenders may (but
; are not obligated to) use this as their output.
:ap-config ; `shared-appender-config`.
:profile-stats ; From `profile` macro.
:instant ; java.util.Date
:timestamp ; String generated from :timestamp-pattern, :timestamp-locale
:hostname ; String
:ns ; String
:instant ; java.util.Date.
:timestamp ; String generated from :timestamp-pattern, :timestamp-locale.
:hostname ; String.
:ns ; String.
MIDDLEWARE
Middleware are fns (applied right-to-left) that transform the map