Files
mermaid/packages/mermaid/src/Diagram.ts
2023-08-21 12:09:38 +05:30

106 lines
3.4 KiB
TypeScript

import * as configApi from './config.js';
import { log } from './logger.js';
import { getDiagram, registerDiagram } from './diagram-api/diagramAPI.js';
import { detectType, getDiagramLoader } from './diagram-api/detectType.js';
import { extractFrontMatter } from './diagram-api/frontmatter.js';
import { UnknownDiagramError } from './errors.js';
import { cleanupComments } from './diagram-api/comments.js';
import type { DetailedError } from './utils.js';
import type { DiagramDefinition } from './diagram-api/types.js';
export type ParseErrorFunction = (err: string | DetailedError | unknown, hash?: any) => void;
/**
* An object representing a parsed mermaid diagram definition.
* @privateRemarks This is exported as part of the public mermaidAPI.
*/
export class Diagram {
type = 'graph';
parser: DiagramDefinition['parser'];
renderer: DiagramDefinition['renderer'];
db: DiagramDefinition['db'];
private init?: DiagramDefinition['init'];
private detectError?: UnknownDiagramError;
constructor(public text: string) {
this.text += '\n';
const cnf = configApi.getConfig();
try {
this.type = detectType(text, cnf);
} catch (e) {
this.type = 'error';
this.detectError = e as UnknownDiagramError;
}
const diagram = getDiagram(this.type);
log.debug('Type ' + this.type);
// Setup diagram
this.db = diagram.db;
this.renderer = diagram.renderer;
this.parser = diagram.parser;
const originalParse = this.parser.parse.bind(this.parser);
// Wrap the jison parse() method to handle extracting frontmatter.
//
// This can't be done in this.parse() because some code
// directly calls diagram.parser.parse(), bypassing this.parse().
//
// Similarly, we can't do this in getDiagramFromText() because some code
// calls diagram.db.clear(), which would reset anything set by
// extractFrontMatter().
this.parser.parse = (text: string) =>
originalParse(cleanupComments(extractFrontMatter(text, this.db, configApi.addDirective)));
this.parser.parser.yy = this.db;
this.init = diagram.init;
this.parse();
}
parse() {
if (this.detectError) {
throw this.detectError;
}
this.db.clear?.();
this.init?.(configApi.getConfig());
this.parser.parse(this.text);
}
async render(id: string, version: string) {
await this.renderer.draw(this.text, id, version, this);
}
getParser() {
return this.parser;
}
getType() {
return this.type;
}
}
/**
* Parse the text asynchronously and generate a Diagram object asynchronously.
* **Warning:** This function may be changed in the future.
* @alpha
* @param text - The mermaid diagram definition.
* @returns A the Promise of a Diagram object.
* @throws {@link UnknownDiagramError} if the diagram type can not be found.
* @privateRemarks This is exported as part of the public mermaidAPI.
*/
export const getDiagramFromText = async (text: string): Promise<Diagram> => {
const type = detectType(text, configApi.getConfig());
try {
// Trying to find the diagram
getDiagram(type);
} catch (error) {
const loader = getDiagramLoader(type);
if (!loader) {
throw new UnknownDiagramError(`Diagram ${type} not found.`);
}
// Diagram not available, loading it.
// new diagram will try getDiagram again and if fails then it is a valid throw
const { id, diagram } = await loader();
registerDiagram(id, diagram);
}
return new Diagram(text);
};