feat(api): allow multiple input files

src/index.ts

@@ -7,7 +7,7 @@ import { getDir } from './lib/helpers';
 import { convertMdToPdf } from './lib/md-to-pdf';
 import { serveDirectory } from './lib/serve-dir';
 
-type Input = ContentInput | PathInput;
+type Input = ContentInput | PathInput | PathsInput;
 
 interface ContentInput {
 	content: string;
@@ -17,17 +17,24 @@ interface PathInput {
 	path: string;
 }
 
+interface PathsInput {
+	paths: string[];
+}
+
 const hasContent = (input: Input): input is ContentInput => 'content' in input;
 const hasPath = (input: Input): input is PathInput => 'path' in input;
+const hasPaths = (input: Input): input is PathsInput => 'paths' in input;
 
 /**
  * Convert a markdown file to PDF.
  */
 export async function mdToPdf(input: ContentInput | PathInput, config?: Partial<PdfConfig>): Promise<PdfOutput>;
 export async function mdToPdf(input: ContentInput | PathInput, config?: Partial<HtmlConfig>): Promise<HtmlOutput>;
-export async function mdToPdf(input: Input, config: Partial<Config> = {}): Promise<Output> {
-	if (!hasContent(input) && !hasPath(input)) {
-		throw new Error('The input is missing one of the properties "content" or "path".');
+export async function mdToPdf(input: PathsInput, config?: Partial<PdfConfig>): Promise<PdfOutput[]>;
+export async function mdToPdf(input: PathsInput, config?: Partial<HtmlConfig>): Promise<HtmlOutput[]>;
+export async function mdToPdf(input: Input, config: Partial<Config> = {}): Promise<Output | Output[]> {
+	if (!hasContent(input) && !hasPath(input) && !hasPaths(input)) {
+		throw new Error('The input is missing one of the properties "content", "path" or "paths".');
 	}
 
 	if (!config.port) {
@@ -38,7 +45,11 @@ export async function mdToPdf(input: Input, config: Partial<Config> = {}): Promi
 		config.basedir = 'path' in input ? getDir(input.path) : process.cwd();
 	}
 
-	if (!config.dest) {
+	if (hasPaths(input) && config.dest) {
+		console.warn('WARNING: config.dest will be ignored when converting multiple files.');
+	}
+
+	if (!config.dest || hasPaths(input)) {
 		config.dest = '';
 	}
 
@@ -50,11 +61,14 @@ export async function mdToPdf(input: Input, config: Partial<Config> = {}): Promi
 
 	const server = await serveDirectory(mergedConfig);
 
-	const pdf = await convertMdToPdf(input, mergedConfig);
+	const result =
+		hasContent(input) || hasPath(input)
+			? await convertMdToPdf(input, mergedConfig)
+			: await Promise.all(input.paths.map(async (path) => convertMdToPdf({ path }, mergedConfig)));
 
 	server.close();
 
-	return pdf;
+	return result;
 }
 
 export default mdToPdf;

src/test/api.spec.ts

@@ -69,3 +69,17 @@ test('compile the MathJax test', async (t) => {
 	t.true(text.startsWith('Formulas with MathJax'));
 	t.true(text.includes('a≠0'));
 });
+
+test('compile multiple files to pdf', async (t) => {
+	const testFile = resolve(__dirname, 'basic', 'test.md');
+
+	const pdfs = await mdToPdf({ paths: [testFile, testFile] });
+
+	t.is(pdfs.length, 2);
+
+	t.is(pdfs[0].filename, '');
+	t.is(pdfs[1].filename, '');
+
+	t.truthy(pdfs[0].content instanceof Buffer);
+	t.truthy(pdfs[1].content instanceof Buffer);
+});

src/test/api.type-spec.ts

@@ -5,9 +5,15 @@ import { HtmlOutput, PdfOutput } from '../lib/generate-output';
 (async () => {
 	expectType<PdfOutput>(await mdToPdf({ content: 'foo' }));
 	expectType<PdfOutput>(await mdToPdf({ path: 'foo.md' }));
-
+	expectType<PdfOutput[]>(await mdToPdf({ paths: ['foo.md'] }));
 	expectType<PdfOutput>(await mdToPdf({ path: 'foo.md' }, { as_html: false }));
 
 	expectType<HtmlOutput>(await mdToPdf({ content: 'foo' }, { as_html: true }));
 	expectType<HtmlOutput>(await mdToPdf({ path: 'foo.md' }, { as_html: true }));
+	expectType<HtmlOutput[]>(await mdToPdf({ paths: ['foo.md'] }, { as_html: true }));
+
+	expectType<string | undefined>((await mdToPdf({ content: 'foo' })).filename);
+
+	expectType<Buffer>((await mdToPdf({ content: 'foo' })).content);
+	expectType<string>((await mdToPdf({ content: 'foo' }, { as_html: true })).content);
 })();