337 lines
9.7 KiB
Python
337 lines
9.7 KiB
Python
"""
|
|
class Renderer
|
|
|
|
Generates HTML from parsed token stream. Each instance has independent
|
|
copy of rules. Those can be rewritten with ease. Also, you can add new
|
|
rules if you create plugin and adds new token types.
|
|
"""
|
|
from __future__ import annotations
|
|
|
|
from collections.abc import Sequence
|
|
import inspect
|
|
from typing import Any, ClassVar, Protocol
|
|
|
|
from .common.utils import escapeHtml, unescapeAll
|
|
from .token import Token
|
|
from .utils import EnvType, OptionsDict
|
|
|
|
|
|
class RendererProtocol(Protocol):
|
|
__output__: ClassVar[str]
|
|
|
|
def render(
|
|
self, tokens: Sequence[Token], options: OptionsDict, env: EnvType
|
|
) -> Any:
|
|
...
|
|
|
|
|
|
class RendererHTML(RendererProtocol):
|
|
"""Contains render rules for tokens. Can be updated and extended.
|
|
|
|
Example:
|
|
|
|
Each rule is called as independent static function with fixed signature:
|
|
|
|
::
|
|
|
|
class Renderer:
|
|
def token_type_name(self, tokens, idx, options, env) {
|
|
# ...
|
|
return renderedHTML
|
|
|
|
::
|
|
|
|
class CustomRenderer(RendererHTML):
|
|
def strong_open(self, tokens, idx, options, env):
|
|
return '<b>'
|
|
def strong_close(self, tokens, idx, options, env):
|
|
return '</b>'
|
|
|
|
md = MarkdownIt(renderer_cls=CustomRenderer)
|
|
|
|
result = md.render(...)
|
|
|
|
See https://github.com/markdown-it/markdown-it/blob/master/lib/renderer.js
|
|
for more details and examples.
|
|
"""
|
|
|
|
__output__ = "html"
|
|
|
|
def __init__(self, parser: Any = None):
|
|
self.rules = {
|
|
k: v
|
|
for k, v in inspect.getmembers(self, predicate=inspect.ismethod)
|
|
if not (k.startswith("render") or k.startswith("_"))
|
|
}
|
|
|
|
def render(
|
|
self, tokens: Sequence[Token], options: OptionsDict, env: EnvType
|
|
) -> str:
|
|
"""Takes token stream and generates HTML.
|
|
|
|
:param tokens: list on block tokens to render
|
|
:param options: params of parser instance
|
|
:param env: additional data from parsed input
|
|
|
|
"""
|
|
result = ""
|
|
|
|
for i, token in enumerate(tokens):
|
|
if token.type == "inline":
|
|
if token.children:
|
|
result += self.renderInline(token.children, options, env)
|
|
elif token.type in self.rules:
|
|
result += self.rules[token.type](tokens, i, options, env)
|
|
else:
|
|
result += self.renderToken(tokens, i, options, env)
|
|
|
|
return result
|
|
|
|
def renderInline(
|
|
self, tokens: Sequence[Token], options: OptionsDict, env: EnvType
|
|
) -> str:
|
|
"""The same as ``render``, but for single token of `inline` type.
|
|
|
|
:param tokens: list on block tokens to render
|
|
:param options: params of parser instance
|
|
:param env: additional data from parsed input (references, for example)
|
|
"""
|
|
result = ""
|
|
|
|
for i, token in enumerate(tokens):
|
|
if token.type in self.rules:
|
|
result += self.rules[token.type](tokens, i, options, env)
|
|
else:
|
|
result += self.renderToken(tokens, i, options, env)
|
|
|
|
return result
|
|
|
|
def renderToken(
|
|
self,
|
|
tokens: Sequence[Token],
|
|
idx: int,
|
|
options: OptionsDict,
|
|
env: EnvType,
|
|
) -> str:
|
|
"""Default token renderer.
|
|
|
|
Can be overridden by custom function
|
|
|
|
:param idx: token index to render
|
|
:param options: params of parser instance
|
|
"""
|
|
result = ""
|
|
needLf = False
|
|
token = tokens[idx]
|
|
|
|
# Tight list paragraphs
|
|
if token.hidden:
|
|
return ""
|
|
|
|
# Insert a newline between hidden paragraph and subsequent opening
|
|
# block-level tag.
|
|
#
|
|
# For example, here we should insert a newline before blockquote:
|
|
# - a
|
|
# >
|
|
#
|
|
if token.block and token.nesting != -1 and idx and tokens[idx - 1].hidden:
|
|
result += "\n"
|
|
|
|
# Add token name, e.g. `<img`
|
|
result += ("</" if token.nesting == -1 else "<") + token.tag
|
|
|
|
# Encode attributes, e.g. `<img src="foo"`
|
|
result += self.renderAttrs(token)
|
|
|
|
# Add a slash for self-closing tags, e.g. `<img src="foo" /`
|
|
if token.nesting == 0 and options["xhtmlOut"]:
|
|
result += " /"
|
|
|
|
# Check if we need to add a newline after this tag
|
|
if token.block:
|
|
needLf = True
|
|
|
|
if token.nesting == 1 and (idx + 1 < len(tokens)):
|
|
nextToken = tokens[idx + 1]
|
|
|
|
if nextToken.type == "inline" or nextToken.hidden: # noqa: SIM114
|
|
# Block-level tag containing an inline tag.
|
|
#
|
|
needLf = False
|
|
|
|
elif nextToken.nesting == -1 and nextToken.tag == token.tag:
|
|
# Opening tag + closing tag of the same type. E.g. `<li></li>`.
|
|
#
|
|
needLf = False
|
|
|
|
result += ">\n" if needLf else ">"
|
|
|
|
return result
|
|
|
|
@staticmethod
|
|
def renderAttrs(token: Token) -> str:
|
|
"""Render token attributes to string."""
|
|
result = ""
|
|
|
|
for key, value in token.attrItems():
|
|
result += " " + escapeHtml(key) + '="' + escapeHtml(str(value)) + '"'
|
|
|
|
return result
|
|
|
|
def renderInlineAsText(
|
|
self,
|
|
tokens: Sequence[Token] | None,
|
|
options: OptionsDict,
|
|
env: EnvType,
|
|
) -> str:
|
|
"""Special kludge for image `alt` attributes to conform CommonMark spec.
|
|
|
|
Don't try to use it! Spec requires to show `alt` content with stripped markup,
|
|
instead of simple escaping.
|
|
|
|
:param tokens: list on block tokens to render
|
|
:param options: params of parser instance
|
|
:param env: additional data from parsed input
|
|
"""
|
|
result = ""
|
|
|
|
for token in tokens or []:
|
|
if token.type == "text":
|
|
result += token.content
|
|
elif token.type == "image":
|
|
if token.children:
|
|
result += self.renderInlineAsText(token.children, options, env)
|
|
elif token.type == "softbreak":
|
|
result += "\n"
|
|
|
|
return result
|
|
|
|
###################################################
|
|
|
|
def code_inline(
|
|
self, tokens: Sequence[Token], idx: int, options: OptionsDict, env: EnvType
|
|
) -> str:
|
|
token = tokens[idx]
|
|
return (
|
|
"<code"
|
|
+ self.renderAttrs(token)
|
|
+ ">"
|
|
+ escapeHtml(tokens[idx].content)
|
|
+ "</code>"
|
|
)
|
|
|
|
def code_block(
|
|
self,
|
|
tokens: Sequence[Token],
|
|
idx: int,
|
|
options: OptionsDict,
|
|
env: EnvType,
|
|
) -> str:
|
|
token = tokens[idx]
|
|
|
|
return (
|
|
"<pre"
|
|
+ self.renderAttrs(token)
|
|
+ "><code>"
|
|
+ escapeHtml(tokens[idx].content)
|
|
+ "</code></pre>\n"
|
|
)
|
|
|
|
def fence(
|
|
self,
|
|
tokens: Sequence[Token],
|
|
idx: int,
|
|
options: OptionsDict,
|
|
env: EnvType,
|
|
) -> str:
|
|
token = tokens[idx]
|
|
info = unescapeAll(token.info).strip() if token.info else ""
|
|
langName = ""
|
|
langAttrs = ""
|
|
|
|
if info:
|
|
arr = info.split(maxsplit=1)
|
|
langName = arr[0]
|
|
if len(arr) == 2:
|
|
langAttrs = arr[1]
|
|
|
|
if options.highlight:
|
|
highlighted = options.highlight(
|
|
token.content, langName, langAttrs
|
|
) or escapeHtml(token.content)
|
|
else:
|
|
highlighted = escapeHtml(token.content)
|
|
|
|
if highlighted.startswith("<pre"):
|
|
return highlighted + "\n"
|
|
|
|
# If language exists, inject class gently, without modifying original token.
|
|
# May be, one day we will add .deepClone() for token and simplify this part, but
|
|
# now we prefer to keep things local.
|
|
if info:
|
|
# Fake token just to render attributes
|
|
tmpToken = Token(type="", tag="", nesting=0, attrs=token.attrs.copy())
|
|
tmpToken.attrJoin("class", options.langPrefix + langName)
|
|
|
|
return (
|
|
"<pre><code"
|
|
+ self.renderAttrs(tmpToken)
|
|
+ ">"
|
|
+ highlighted
|
|
+ "</code></pre>\n"
|
|
)
|
|
|
|
return (
|
|
"<pre><code"
|
|
+ self.renderAttrs(token)
|
|
+ ">"
|
|
+ highlighted
|
|
+ "</code></pre>\n"
|
|
)
|
|
|
|
def image(
|
|
self,
|
|
tokens: Sequence[Token],
|
|
idx: int,
|
|
options: OptionsDict,
|
|
env: EnvType,
|
|
) -> str:
|
|
token = tokens[idx]
|
|
|
|
# "alt" attr MUST be set, even if empty. Because it's mandatory and
|
|
# should be placed on proper position for tests.
|
|
if token.children:
|
|
token.attrSet("alt", self.renderInlineAsText(token.children, options, env))
|
|
else:
|
|
token.attrSet("alt", "")
|
|
|
|
return self.renderToken(tokens, idx, options, env)
|
|
|
|
def hardbreak(
|
|
self, tokens: Sequence[Token], idx: int, options: OptionsDict, env: EnvType
|
|
) -> str:
|
|
return "<br />\n" if options.xhtmlOut else "<br>\n"
|
|
|
|
def softbreak(
|
|
self, tokens: Sequence[Token], idx: int, options: OptionsDict, env: EnvType
|
|
) -> str:
|
|
return (
|
|
("<br />\n" if options.xhtmlOut else "<br>\n") if options.breaks else "\n"
|
|
)
|
|
|
|
def text(
|
|
self, tokens: Sequence[Token], idx: int, options: OptionsDict, env: EnvType
|
|
) -> str:
|
|
return escapeHtml(tokens[idx].content)
|
|
|
|
def html_block(
|
|
self, tokens: Sequence[Token], idx: int, options: OptionsDict, env: EnvType
|
|
) -> str:
|
|
return tokens[idx].content
|
|
|
|
def html_inline(
|
|
self, tokens: Sequence[Token], idx: int, options: OptionsDict, env: EnvType
|
|
) -> str:
|
|
return tokens[idx].content
|