gitlab-org--gitlab-foss/doc/user/asciidoc.md

511 lines
11 KiB
Markdown
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

---
stage: Create
group: Source Code
info: "To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments"
type: reference, howto
---
# AsciiDoc
GitLab uses the [Asciidoctor](https://asciidoctor.org) gem to convert AsciiDoc content to HTML5.
Consult the [Asciidoctor User Manual](https://asciidoctor.org/docs/user-manual/) for a complete Asciidoctor reference.
## Syntax
Here's a brief reference of the most commonly used AsciiDoc syntax.
You can find the full documentation for the AsciiDoc syntax at <https://asciidoctor.org/docs/>.
### Paragraphs
```plaintext
A normal paragraph.
Line breaks are not preserved.
```
Line comments, which are lines that start with `//`, are skipped:
```plaintext
// this is a comment
```
A blank line separates paragraphs.
A paragraph with the `[%hardbreaks]` option will preserve line breaks:
```plaintext
[%hardbreaks]
This paragraph carries the `hardbreaks` option.
Notice how line breaks are now preserved.
```
An indented (literal) paragraph disables text formatting,
preserves spaces and line breaks, and is displayed in a
monospaced font:
```plaintext
This literal paragraph is indented with one space.
As a consequence, *text formatting*, spaces,
and lines breaks will be preserved.
```
An admonition paragraph grabs the reader's attention:
```plaintext
NOTE: This is a brief reference, please read the full documentation at https://asciidoctor.org/docs/.
TIP: Lists can be indented. Leading whitespace is not significant.
```
### Text Formatting
**Constrained (applied at word boundaries)**
```plaintext
*strong importance* (aka bold)
_stress emphasis_ (aka italic)
`monospaced` (aka typewriter text)
"`double`" and '`single`' typographic quotes
+passthrough text+ (substitutions disabled)
`+literal text+` (monospaced with substitutions disabled)
```
**Unconstrained (applied anywhere)**
```plaintext
**C**reate+**R**ead+**U**pdate+**D**elete
fan__freakin__tastic
``mono``culture
```
**Replacements**
```plaintext
A long time ago in a galaxy far, far away...
(C) 1976 Arty Artisan
I believe I shall--no, actually I won't.
```
**Macros**
```plaintext
// where c=specialchars, q=quotes, a=attributes, r=replacements, m=macros, p=post_replacements, etc.
The European icon:flag[role=blue] is blue & contains pass:[************] arranged in a icon:circle-o[role=yellow].
The pass:c[->] operator is often referred to as the stabby lambda.
Since `pass:[++]` has strong priority in AsciiDoc, you can rewrite pass:c,a,r[C++ => C{pp}].
// activate stem support by adding `:stem:` to the document header
stem:[sqrt(4) = 2]
```
### Attributes
**User-defined attributes**
```plaintext
// define attributes in the document header
:name: value
```
```plaintext
:url-gem: https://rubygems.org/gems/asciidoctor
You can download and install Asciidoctor {asciidoctor-version} from {url-gem}.
C{pp} is not required, only Ruby.
Use a leading backslash to output a word enclosed in curly braces, like \{name}.
```
**Environment attributes**
GitLab sets the following environment attributes:
| Attribute | Description |
| :-------------- | :--------------------------------------------------------------------------------------------------------------------- |
| `docname` | Root name of the source document (no leading path or file extension). |
| `outfilesuffix` | File extension corresponding to the backend output (defaults to `.adoc` to make inter-document cross references work). |
### Links
```plaintext
https://example.org/page[A webpage]
link:../path/to/file.txt[A local file]
xref:document.adoc[A sibling document]
mailto:hello@example.org[Email to say hello!]
```
### Anchors
```plaintext
[[idname,reference text]]
// or written using normal block attributes as `[#idname,reftext=reference text]`
A paragraph (or any block) with an anchor (aka ID) and reftext.
See <<idname>> or <<idname,optional text of internal link>>.
xref:document.adoc#idname[Jumps to anchor in another document].
This paragraph has a footnote.footnote:[This is the text of the footnote.]
```
### Lists
#### Unordered
```plaintext
* level 1
** level 2
*** level 3
**** level 4
***** etc.
* back at level 1
+
Attach a block or paragraph to a list item using a list continuation (which you can enclose in an open block).
.Some Authors
[circle]
- Edgar Allen Poe
- Sheri S. Tepper
- Bill Bryson
```
#### Ordered
```plaintext
. Step 1
. Step 2
.. Step 2a
.. Step 2b
. Step 3
.Remember your Roman numerals?
[upperroman]
. is one
. is two
. is three
```
#### Checklist
```plaintext
* [x] checked
* [ ] not checked
```
#### Callout
```plaintext
// enable callout bubbles by adding `:icons: font` to the document header
[,ruby]
----
puts 'Hello, World!' # <1>
----
<1> Prints `Hello, World!` to the console.
```
#### Description
```plaintext
first term:: description of first term
second term::
description of second term
```
### Document Structure
#### Header
```plaintext
= Document Title
Author Name <author@example.org>
v1.0, 2019-01-01
```
#### Sections
```plaintext
= Document Title (Level 0)
== Level 1
=== Level 2
==== Level 3
===== Level 4
====== Level 5
== Back at Level 1
```
#### Includes
```plaintext
include::basics.adoc[]
// define -a allow-uri-read to allow content to be read from URI
include::https://example.org/installation.adoc[]
```
To guarantee good system performance and prevent malicious documents causing
problems, GitLab enforces a **maximum limit** on the number of include directives
processed in any one document. Currently a total of 32 documents can be
included, a number that is inclusive of transitive dependencies.
### Blocks
```plaintext
--
open - a general-purpose content wrapper; useful for enclosing content to attach to a list item
--
```
```plaintext
// recognized types include CAUTION, IMPORTANT, NOTE, TIP, and WARNING
// enable admonition icons by setting `:icons: font` in the document header
[NOTE]
====
admonition - a notice for the reader, ranging in severity from a tip to an alert
====
```
```plaintext
====
example - a demonstration of the concept being documented
====
```
```plaintext
.Toggle Me
[%collapsible]
====
collapsible - these details are revealed by clicking the title
====
```
```plaintext
****
sidebar - auxiliary content that can be read independently of the main content
****
```
```plaintext
....
literal - an exhibit that features program output
....
```
```plaintext
----
listing - an exhibit that features program input, source code, or the contents of a file
----
```
```plaintext
[,language]
----
source - a listing that is embellished with (colorized) syntax highlighting
----
```
````plaintext
\```language
fenced code - a shorthand syntax for the source block
\```
````
```plaintext
[,attribution,citetitle]
____
quote - a quotation or excerpt; attribution with title of source are optional
____
```
```plaintext
[verse,attribution,citetitle]
____
verse - a literary excerpt, often a poem; attribution with title of source are optional
____
```
```plaintext
++++
pass - content passed directly to the output document; often raw HTML
++++
```
```plaintext
// activate stem support by adding `:stem:` to the document header
[stem]
++++
x = y^2
++++
```
```plaintext
////
comment - content which is not included in the output document
////
```
### Tables
```plaintext
.Table Attributes
[cols=>1h;2d,width=50%,frame=topbot]
|===
| Attribute Name | Values
| options
| header,footer,autowidth
| cols
| colspec[;colspec;...]
| grid
| all \| cols \| rows \| none
| frame
| all \| sides \| topbot \| none
| stripes
| all \| even \| odd \| none
| width
| (0%..100%)
| format
| psv {vbar} csv {vbar} dsv
|===
```
### Colors
Its possible to have color written in `HEX`, `RGB`, or `HSL` format rendered with a color indicator.
Supported formats (named colors are not supported):
- HEX: `` `#RGB[A]` `` or `` `#RRGGBB[AA]` ``
- RGB: `` `RGB[A](R, G, B[, A])` ``
- HSL: `` `HSL[A](H, S, L[, A])` ``
Color written inside backticks will be followed by a color "chip":
```plaintext
- `#F00`
- `#F00A`
- `#FF0000`
- `#FF0000AA`
- `RGB(0,255,0)`
- `RGB(0%,100%,0%)`
- `RGBA(0,255,0,0.3)`
- `HSL(540,70%,50%)`
- `HSLA(540,70%,50%,0.3)`
```
### STEM
To activate equation and formula support,
set the `stem` attribute in the document's header to `latexmath`.
Equations and formulas will be rendered using [KaTeX](https://katex.org/):
```plaintext
:stem: latexmath
latexmath:[C = \alpha + \beta Y^{\gamma} + \epsilon]
[stem]
++++
sqrt(4) = 2
++++
A matrix can be written as stem:[[[a,b\],[c,d\]\]((n),(k))].
```
### Diagrams and flowcharts
It's possible to generate diagrams and flowcharts from text in GitLab using
[Mermaid](https://mermaidjs.github.io/) or [PlantUML](https://plantuml.com).
#### Mermaid
> [Introduced](https://gitlab.com/gitlab-org/gitlab/-/issues/31818) in GitLab 13.3.
Visit the [official page](https://mermaidjs.github.io/) for more details.
If you're new to using Mermaid or need help identifying issues in your Mermaid code,
the [Mermaid Live Editor](https://mermaid-js.github.io/mermaid-live-editor/) is a helpful tool
for creating and resolving issues within Mermaid diagrams.
In order to generate a diagram or flowchart, you should write your text inside the `mermaid` block:
```plaintext
[mermaid]
----
graph LR
A[Square Rect] -- Link text --> B((Circle))
A --> C(Round Rect)
B --> D{Rhombus}
C --> D
----
```
#### Kroki
Kroki supports more than a dozen diagram libraries.
To make Kroki available in GitLab, a GitLab administrator needs to enable it first.
Read more in the [Kroki integration](../administration/integration/kroki.md) page.
Once Kroki is enabled, you can create a wide variety of diagrams in AsciiDoc and Markdown documents.
Here's an example using a GraphViz diagram:
**AsciiDoc**
```plaintext
[graphviz]
....
digraph G {
Hello->World
}
....
```
**Markdown**
````markdown
```graphviz
digraph G {
Hello->World
}
```
````
#### PlantUML
To make PlantUML available in GitLab, a GitLab administrator needs to enable it first.
Read more in [PlantUML & GitLab](../administration/integration/plantuml.md).
Once enabled, you should write your text inside the `plantuml` block:
```plaintext
[plantuml]
----
Bob -> Alice : hello
----
```
### Multimedia
```plaintext
image::screenshot.png[block image,800,450]
Press image:reload.svg[reload,16,opts=interactive] to reload the page.
video::movie.mp4[width=640,start=60,end=140,options=autoplay]
video::aHjpOzsQ9YI[youtube]
video::300817511[vimeo]
```
### Breaks
```plaintext
// thematic break (aka horizontal rule)
---
```
```plaintext
// page break
<<<
```