Generating Documentation
Skydoc

Generating Documentation

The following are some examples of how to use Stardoc.

Single File

Suppose you have a project containing Stardoc rules you want to document:

[workspace]/
    WORKSPACE
    checkstyle/
        BUILD
        checkstyle.bzl

To generate documentation for the rules in checkstyle.bzl, add the following target to rules/BUILD:

load("@io_bazel_skydoc//stardoc:stardoc.bzl", "stardoc")

stardoc(
    name = "checkstyle-docs",
    input = "checkstyle.bzl",
    out = "checkstyle_doc.md",
)

Running bazel build //checkstyle:checkstyle-docs will generate a markdown file containing documentation for all Starlark rules defined in checkstyle.bzl.

To generate a subset of rules defined in checkstyle.bzl, you may specify which rule names you specifically want documentation for using the symbol_names attribute of the stardoc rule. If symbol_names is specified, only rules matching a name in symbol_names will be documented:

load("@io_bazel_skydoc//stardoc:stardoc.bzl", "stardoc")

stardoc(
    name = "checkstyle-docs",
    input = "checkstyle.bzl",
    out = "checkstyle_doc.md",
    symbol_names = ["checkstyle_rule", "other_rule"],
)

Files with Dependencies

If you would like to generate documentation for a .bzl with dependencies on other .bzl files, use the bzl_library rule to create logical collections of Starlark sources and depend on these libraries via the deps attribute of your stardoc target.

Suppose your project has the following structure:

[workspace]/
    WORKSPACE
    BUILD
    checkstyle/
        BUILD
        checkstyle.bzl
    lua/
        BUILD
        lua.bzl
        luarocks.bzl

...and suppose your target .bzl file depends on other .bzl files in your workspace:

checkstyle/checkstyle.bzl:

load("//lua:lua.bzl", "lua_utility")

lua_utility()

checkstyle_rule = rule(
    ...
)

In this case, you can have a bzl_library target in lua/BUILD:

lua/BUILD:

load("@bazel_skylib//:bzl_library.bzl", "bzl_library")

bzl_library(
    name = "lua-rules",
    srcs = [
        "lua.bzl",
        "luarocks.bzl",
    ],
)

To build documentation for checkstyle.bzl, specify the bzl_library target as a dependency of the stardoc target:

checkstyle/BUILD:

load("@io_bazel_skydoc//stardoc:stardoc.bzl", "stardoc")

stardoc(
    name = "checkstyle-docs",
    input = "checkstyle.bzl",
    out = "checkstyle_doc.md",
    deps = ["//lua:lua-rules"],
)

Multiple Files

If you would like to generate documentation for multiple .bzl files in various packages in your workspace, you will need to create a single .bzl file that depends on all those .bzl files. You can then explicitly whitelist rules for which you would like documentation to be generated.

For example, you may want to generate documentation for foo_rule, bar_rule, and baz_rule, all in different .bzl files. First, you would create a single .bzl file which loads these files:

doc_hub.bzl:

load("//foo:foo.bzl", "foo_rule")
load("//bar:bar.bzl", "bar_rule")
load("//baz:baz.bzl", "baz_rule")

# No need for any implementation here. The rules need only be loaded.

A single skydoc target can then be used to generate their documentation:

BUILD:

load("@io_bazel_skydoc//stardoc:stardoc.bzl", "stardoc")

stardoc(
    name = "my-docs",
    input = "doc_hub.bzl",
    out = "docs.md",
    symbol_names = ["foo_rule", "bar_rule", "baz_rule"],
)