File size: 5,252 Bytes
d1ceb73 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 |
"""Machinery for documenting traitlets config options with Sphinx.
This includes:
- A Sphinx extension defining directives and roles for config options.
- A function to generate an rst file given an Application instance.
To make this documentation, first set this module as an extension in Sphinx's
conf.py::
extensions = [
# ...
'traitlets.config.sphinxdoc',
]
Autogenerate the config documentation by running code like this before
Sphinx builds::
from traitlets.config.sphinxdoc import write_doc
from myapp import MyApplication
writedoc('config/options.rst', # File to write
'MyApp config options', # Title
MyApplication()
)
The generated rST syntax looks like this::
.. configtrait:: Application.log_datefmt
Description goes here.
Cross reference like this: :configtrait:`Application.log_datefmt`.
"""
from __future__ import annotations
import typing as t
from collections import defaultdict
from textwrap import dedent
from traitlets import HasTraits, Undefined
from traitlets.config.application import Application
from traitlets.utils.text import indent
def setup(app: t.Any) -> dict[str, t.Any]:
"""Registers the Sphinx extension.
You shouldn't need to call this directly; configure Sphinx to use this
module instead.
"""
app.add_object_type("configtrait", "configtrait", objname="Config option")
return {"parallel_read_safe": True, "parallel_write_safe": True}
def interesting_default_value(dv: t.Any) -> bool:
if (dv is None) or (dv is Undefined):
return False
if isinstance(dv, (str, list, tuple, dict, set)):
return bool(dv)
return True
def format_aliases(aliases: list[str]) -> str:
fmted = []
for a in aliases:
dashes = "-" if len(a) == 1 else "--"
fmted.append(f"``{dashes}{a}``")
return ", ".join(fmted)
def class_config_rst_doc(cls: type[HasTraits], trait_aliases: dict[str, t.Any]) -> str:
"""Generate rST documentation for this class' config options.
Excludes traits defined on parent classes.
"""
lines = []
classname = cls.__name__
for _, trait in sorted(cls.class_traits(config=True).items()):
ttype = trait.__class__.__name__
fullname = classname + "." + (trait.name or "")
lines += [".. configtrait:: " + fullname, ""]
help = trait.help.rstrip() or "No description"
lines.append(indent(dedent(help)) + "\n")
# Choices or type
if "Enum" in ttype:
# include Enum choices
lines.append(indent(":options: " + ", ".join("``%r``" % x for x in trait.values))) # type:ignore[attr-defined]
else:
lines.append(indent(":trait type: " + ttype))
# Default value
# Ignore boring default values like None, [] or ''
if interesting_default_value(trait.default_value):
try:
dvr = trait.default_value_repr()
except Exception:
dvr = None # ignore defaults we can't construct
if dvr is not None:
if len(dvr) > 64:
dvr = dvr[:61] + "..."
# Double up backslashes, so they get to the rendered docs
dvr = dvr.replace("\\n", "\\\\n")
lines.append(indent(":default: ``%s``" % dvr))
# Command line aliases
if trait_aliases[fullname]:
fmt_aliases = format_aliases(trait_aliases[fullname])
lines.append(indent(":CLI option: " + fmt_aliases))
# Blank line
lines.append("")
return "\n".join(lines)
def reverse_aliases(app: Application) -> dict[str, list[str]]:
"""Produce a mapping of trait names to lists of command line aliases."""
res = defaultdict(list)
for alias, trait in app.aliases.items():
res[trait].append(alias)
# Flags also often act as aliases for a boolean trait.
# Treat flags which set one trait to True as aliases.
for flag, (cfg, _) in app.flags.items():
if len(cfg) == 1:
classname = next(iter(cfg))
cls_cfg = cfg[classname]
if len(cls_cfg) == 1:
traitname = next(iter(cls_cfg))
if cls_cfg[traitname] is True:
res[classname + "." + traitname].append(flag)
return res
def write_doc(path: str, title: str, app: Application, preamble: str | None = None) -> None:
"""Write a rst file documenting config options for a traitlets application.
Parameters
----------
path : str
The file to be written
title : str
The human-readable title of the document
app : traitlets.config.Application
An instance of the application class to be documented
preamble : str
Extra text to add just after the title (optional)
"""
trait_aliases = reverse_aliases(app)
with open(path, "w") as f:
f.write(title + "\n")
f.write(("=" * len(title)) + "\n")
f.write("\n")
if preamble is not None:
f.write(preamble + "\n\n")
for c in app._classes_inc_parents():
f.write(class_config_rst_doc(c, trait_aliases))
f.write("\n")
|