mirror of
https://github.com/mermaid-js/mermaid.git
synced 2025-10-23 07:59:39 +02:00
b7d31adda4
The `node16` module resolution requires imports to use the `.js` file extension in type definitions. `@rollup/plugin-typescript` is needed to make this work with the Vite setup used by Mermaid. The module option for Mermaid internally is set to `nodenext`. This is needed to support `.json` imports. Note that setting `module` to `node16` or `nodenext` implies a matching `moduleResolution` value.
41 lines
1.5 KiB
TypeScript
41 lines
1.5 KiB
TypeScript
import { DiagramDb } from './types.js';
|
|
// The "* as yaml" part is necessary for tree-shaking
|
|
import * as yaml from 'js-yaml';
|
|
|
|
// Match Jekyll-style front matter blocks (https://jekyllrb.com/docs/front-matter/).
|
|
// Based on regex used by Jekyll: https://github.com/jekyll/jekyll/blob/6dd3cc21c40b98054851846425af06c64f9fb466/lib/jekyll/document.rb#L10
|
|
// Note that JS doesn't support the "\A" anchor, which means we can't use
|
|
// multiline mode.
|
|
// Relevant YAML spec: https://yaml.org/spec/1.2.2/#914-explicit-documents
|
|
export const frontMatterRegex = /^-{3}\s*[\n\r](.*?)[\n\r]-{3}\s*[\n\r]+/s;
|
|
|
|
type FrontMatterMetadata = {
|
|
title?: string;
|
|
};
|
|
|
|
/**
|
|
* Extract and parse frontmatter from text, if present, and sets appropriate
|
|
* properties in the provided db.
|
|
* @param text - The text that may have a YAML frontmatter.
|
|
* @param db - Diagram database, could be of any diagram.
|
|
* @returns text with frontmatter stripped out
|
|
*/
|
|
export function extractFrontMatter(text: string, db: DiagramDb): string {
|
|
const matches = text.match(frontMatterRegex);
|
|
if (matches) {
|
|
const parsed: FrontMatterMetadata = yaml.load(matches[1], {
|
|
// To keep things simple, only allow strings, arrays, and plain objects.
|
|
// https://www.yaml.org/spec/1.2/spec.html#id2802346
|
|
schema: yaml.FAILSAFE_SCHEMA,
|
|
}) as FrontMatterMetadata;
|
|
|
|
if (parsed?.title) {
|
|
db.setDiagramTitle?.(parsed.title);
|
|
}
|
|
|
|
return text.slice(matches[0].length);
|
|
} else {
|
|
return text;
|
|
}
|
|
}
|