d47c7fa12b
This makes the awkward withDoctype utility obsolete which is much nicer.
Technically, this is a BREAKING CHANGE since it was possible to create
valid documents without an <html> tag before:
withDoctype (lib.concatStrings [ (<head> { } …) (<body> { } …) ])
I don't think this usecase is worth preserving since this can just be
written as
<html> { } [ (<head> { } …) (<body> { } …) ]
and omitting the <html> tag is not recommended since it should be used
to set the language of the document (which we didn't in the example
above).
Change-Id: Idc5104ce88fe8bee965c076229b79387915c3605
Reviewed-on: https://cl.tvl.fyi/c/depot/+/12907
Autosubmit: sterni <sternenseemann@systemli.org>
Reviewed-by: sterni <sternenseemann@systemli.org>
Tested-by: BuildkiteCI
Reviewed-by: tazjin <tazjin@tvl.su>
127 lines
3.5 KiB
Nix
127 lines
3.5 KiB
Nix
# SPDX-FileCopyrightText: Copyright © 2021, 2024 sterni
|
|
# SPDX-License-Identifier: MIT
|
|
#
|
|
# This file provides a cursed HTML DSL for nix which works by overloading
|
|
# the NIX_PATH lookup operation via angle bracket operations, e. g. `<nixpkgs>`.
|
|
|
|
{ ... }:
|
|
|
|
let
|
|
/* Escape everything we have to escape in an HTML document if either
|
|
in a normal context or an attribute string (`<>&"'`).
|
|
|
|
A shorthand for this function called `esc` is also provided.
|
|
|
|
Type: string -> string
|
|
|
|
Example:
|
|
|
|
escapeMinimal "<hello>"
|
|
=> "<hello>"
|
|
*/
|
|
escapeMinimal = builtins.replaceStrings
|
|
[ "<" ">" "&" "\"" "'" ]
|
|
[ "<" ">" "&" """ "'" ];
|
|
|
|
/* Return a string with a correctly rendered tag of the given name,
|
|
with the given attributes which are automatically escaped.
|
|
|
|
If the content argument is `null`, the tag will have no children nor a
|
|
closing element. If the content argument is a string it is used as the
|
|
content as is (unescaped). If the content argument is a list, its
|
|
elements are concatenated (recursively if necessary).
|
|
|
|
`renderTag` is only an internal function which is reexposed as `__findFile`
|
|
to allow for much neater syntax than calling `renderTag` everywhere:
|
|
|
|
```nix
|
|
{ depot, ... }:
|
|
let
|
|
inherit (depot.users.sterni.nix.html) __findFile esc;
|
|
in
|
|
|
|
<html> {} [
|
|
(<head> {} (<title> {} (esc "hello world")))
|
|
(<body> {} [
|
|
(<h1> {} (esc "hello world"))
|
|
(<p> {} (esc "foo bar"))
|
|
])
|
|
]
|
|
|
|
```
|
|
|
|
As you can see, the need to call a function disappears, instead the
|
|
`NIX_PATH` lookup operation via `<foo>` is overloaded, so it becomes
|
|
`renderTag "foo"` automatically.
|
|
|
|
Since the content argument may contain the result of other `renderTag`
|
|
calls, we can't escape it automatically. Instead this must be done manually
|
|
using `esc`.
|
|
|
|
If the tag is "html", e.g. in case of `<html> { } …`, "<!DOCTYPE html> will
|
|
be prepended to the normal rendering of the text.
|
|
|
|
Type: string -> attrs<string> -> (list<string> | string | null) -> string
|
|
|
|
Example:
|
|
|
|
<link> {
|
|
rel = "stylesheet";
|
|
href = "/css/main.css";
|
|
type = "text/css";
|
|
} null
|
|
|
|
renderTag "link" {
|
|
rel = "stylesheet";
|
|
href = "/css/main.css";
|
|
type = "text/css";
|
|
} null
|
|
|
|
=> "<link href=\"/css/main.css\" rel=\"stylesheet\" type=\"text/css\"/>"
|
|
|
|
<p> {} [
|
|
"foo "
|
|
(<strong> {} "bar")
|
|
]
|
|
|
|
renderTag "p" {} "foo <strong>bar</strong>"
|
|
=> "<p>foo <strong>bar</strong></p>"
|
|
*/
|
|
renderTag = tag: attrs: content:
|
|
let
|
|
attrs' = builtins.concatStringsSep "" (
|
|
builtins.map
|
|
(n:
|
|
" ${escapeMinimal n}=\"${escapeMinimal (toString attrs.${n})}\""
|
|
)
|
|
(builtins.attrNames attrs)
|
|
);
|
|
content' =
|
|
if builtins.isList content
|
|
then builtins.concatStringsSep "" (flatten content)
|
|
else content;
|
|
in
|
|
(if tag == "html" then "<!DOCTYPE html>" else "") +
|
|
(if content == null
|
|
then "<${tag}${attrs'}/>"
|
|
else "<${tag}${attrs'}>${content'}</${tag}>");
|
|
|
|
/* Deprecated, does nothing.
|
|
*/
|
|
withDoctype = doc: builtins.trace
|
|
"WARN: withDoctype no longer does anything, `<html> { } [ … ]` takes care of rendering <!DOCTYPE html>"
|
|
doc;
|
|
|
|
/* Taken from <nixpkgs/lib/lists.nix>. */
|
|
flatten = x:
|
|
if builtins.isList x
|
|
then builtins.concatMap (y: flatten y) x
|
|
else [ x ];
|
|
|
|
in
|
|
{
|
|
inherit escapeMinimal renderTag withDoctype;
|
|
|
|
__findFile = _: renderTag;
|
|
esc = escapeMinimal;
|
|
}
|