kibana/docs/dev-tools/grokdebugger/index.asciidoc
florent-leborgne 8e7fb7a77e
[Docs] Update nav instructions and sample data installation to accommodate for the solution views (#199163)
This PR:
- updates navigation instructions to accommodate for the navigation
changes related to solution views.
- updates instructions for adding sample data to rely on the
integrations page instead of the home page, that only exists with the
classic solution view
- updates references to the home page to avoid confusing users using one
of the new solution views

Closes: https://github.com/elastic/platform-docs-team/issues/529
Closes: https://github.com/elastic/platform-docs-team/issues/540
2024-11-08 11:10:32 +01:00

121 lines
4.6 KiB
Text

[role="xpack"]
[[xpack-grokdebugger]]
== Debug grok expressions
You can build and debug grok patterns in the {kib} *Grok Debugger*
before you use them in your data processing pipelines. Grok is a pattern
matching syntax that you can use to parse arbitrary text and
structure it. Grok is good for parsing syslog, apache, and other
webserver logs, mysql logs, and in general, any log format that is
written for human consumption.
Grok patterns are supported in {es} {ref}/runtime.html[runtime fields], the {es}
{ref}/grok-processor.html[grok ingest processor], and the {ls}
{logstash-ref}/plugins-filters-grok.html[grok filter]. For syntax, see
{ref}/grok.html[Grokking grok].
The {stack} ships with more than 120 reusable grok patterns. For a complete
list of patterns, see
https://github.com/elastic/elasticsearch/tree/master/libs/grok/src/main/resources/patterns[{es}
grok patterns] and
https://github.com/logstash-plugins/logstash-patterns-core/tree/master/patterns[{ls}
grok patterns].
Because
{es} and {ls} share the same grok implementation and pattern
libraries, any grok pattern that you create in the *Grok Debugger* will work
in both {es} and {ls}.
[float]
[[grokdebugger-getting-started]]
=== Get started
This example walks you through using the *Grok Debugger*. This tool
is automatically enabled in {kib}.
NOTE: If you're using {stack-security-features}, you must have the `manage_pipeline`
permission to use the Grok Debugger.
. Find the *Grok Debugger* by navigating to the *Developer tools* page using the
navigation menu or the <<kibana-navigation-search,global search field>>.
. In *Sample Data*, enter a message that is representative of the data that you
want to parse. For example:
+
[source,ruby]
-------------------------------------------------------------------------------
55.3.244.1 GET /index.html 15824 0.043
-------------------------------------------------------------------------------
. In *Grok Pattern*, enter the grok pattern that you want to apply to the data.
+
To parse the log line in this example, use:
+
[source,ruby]
-------------------------------------------------------------------------------
%{IP:client} %{WORD:method} %{URIPATHPARAM:request} %{NUMBER:bytes} %{NUMBER:duration}
-------------------------------------------------------------------------------
. Click **Simulate**.
+
You'll see the simulated event that results from applying the grok
pattern.
+
[role="screenshot"]
image::dev-tools/grokdebugger/images/grok-debugger-overview.png["Grok Debugger"]
//TODO: Update LS and ingest node docs with pointers to the new grok debugger. Replace references to the Heroku app.
[float]
[[grokdebugger-custom-patterns]]
=== Test custom patterns
If the default grok pattern dictionary doesn't contain the patterns you need,
you can define, test, and debug custom patterns using the *Grok Debugger*.
Custom patterns that you enter in the *Grok Debugger* are not saved. Custom patterns
are only available for the current debugging session and have no side effects.
Follow this example to define a custom pattern.
. In *Sample Data*, enter the following sample message:
+
[source,ruby]
-------------------------------------------------------------------------------
Jan 1 06:25:43 mailserver14 postfix/cleanup[21403]: BEF25A72965: message-id=<20130101142543.5828399CCAF@mailserver14.example.com>
-------------------------------------------------------------------------------
. Enter this grok pattern:
+
[source,ruby]
-------------------------------------------------------------------------------
%{SYSLOGBASE} %{POSTFIX_QUEUEID:queue_id}: %{MSG:syslog_message}
-------------------------------------------------------------------------------
+
Notice that the grok pattern references custom patterns called `POSTFIX_QUEUEID`
and `MSG`.
. Expand **Custom Patterns** and enter pattern definitions for the custom
patterns that you want to use in the grok expression. You must specify each pattern definition
on its own line.
+
For this example, you must specify pattern definitions
for `POSTFIX_QUEUEID` and `MSG`:
+
[source,ruby]
-------------------------------------------------------------------------------
POSTFIX_QUEUEID [0-9A-F]{10,11}
MSG message-id=<%{GREEDYDATA}>
-------------------------------------------------------------------------------
. Click **Simulate**.
+
You'll see the simulated output event that results from applying
the grok pattern that contains the custom pattern:
+
[role="screenshot"]
image::dev-tools/grokdebugger/images/grok-debugger-custom-pattern.png["Debugging a custom pattern"]
+
If an error occurs, you can continue iterating over
the custom pattern until the output matches the event
that you expect.