rizaldy.club/quartz/plugins/transformers/frontmatter.ts
2023-12-28 08:48:14 -08:00

87 lines
2.4 KiB
TypeScript

import matter from "gray-matter"
import remarkFrontmatter from "remark-frontmatter"
import { QuartzTransformerPlugin } from "../types"
import yaml from "js-yaml"
import toml from "toml"
import { slugTag } from "../../util/path"
import { QuartzPluginData } from "../vfile"
export interface Options {
delims: string | string[]
language: "yaml" | "toml"
oneLineTagDelim: string
}
const defaultOptions: Options = {
delims: "---",
language: "yaml",
oneLineTagDelim: ",",
}
export const FrontMatter: QuartzTransformerPlugin<Partial<Options> | undefined> = (userOpts) => {
const opts = { ...defaultOptions, ...userOpts }
return {
name: "FrontMatter",
markdownPlugins() {
const { oneLineTagDelim } = opts
return [
[remarkFrontmatter, ["yaml", "toml"]],
() => {
return (_, file) => {
const { data } = matter(Buffer.from(file.value), {
...opts,
engines: {
yaml: (s) => yaml.load(s, { schema: yaml.JSON_SCHEMA }) as object,
toml: (s) => toml.parse(s) as object,
},
})
// tag is an alias for tags
if (data.tag) {
data.tags = data.tag
}
// coerce title to string
if (data.title) {
data.title = data.title.toString()
} else if (data.title === null || data.title === undefined) {
data.title = file.stem ?? "Untitled"
}
if (data.tags) {
// coerce to array
if (!Array.isArray(data.tags)) {
data.tags = data.tags
.toString()
.split(oneLineTagDelim)
.map((tag: string) => tag.trim())
}
// remove all non-string tags
data.tags = data.tags
.filter((tag: unknown) => typeof tag === "string" || typeof tag === "number")
.map((tag: string | number) => tag.toString())
}
// slug them all!!
data.tags = [...new Set(data.tags?.map((tag: string) => slugTag(tag)))]
// fill in frontmatter
file.data.frontmatter = data as QuartzPluginData["frontmatter"]
}
},
]
},
}
}
declare module "vfile" {
interface DataMap {
frontmatter: { [key: string]: any } & {
title: string
tags: string[]
}
}
}