| import fs from 'fs/promises' |
| import path from 'path' |
| import url from 'url' |
| import type { RawSourceMap } from 'next/dist/compiled/source-map08' |
| import dataUriToBuffer from 'next/dist/compiled/data-uri-to-buffer' |
|
|
| function getSourceMapUrl(fileContents: string): string | null { |
| const regex = /\/\/[#@] ?sourceMappingURL=([^\s'"]+)\s*$/gm |
| let match = null |
| for (;;) { |
| let next = regex.exec(fileContents) |
| if (next == null) { |
| break |
| } |
| match = next |
| } |
| if (!(match && match[1])) { |
| return null |
| } |
| return match[1].toString() |
| } |
|
|
| export async function getSourceMapFromFile( |
| filename: string |
| ): Promise<RawSourceMap | undefined> { |
| filename = filename.startsWith('file://') |
| ? url.fileURLToPath(filename) |
| : filename |
|
|
| let fileContents: string |
|
|
| try { |
| fileContents = await fs.readFile(filename, 'utf-8') |
| } catch (error) { |
| throw new Error(`Failed to read file contents of ${filename}.`, { |
| cause: error, |
| }) |
| } |
|
|
| const sourceUrl = getSourceMapUrl(fileContents) |
|
|
| if (!sourceUrl) { |
| return undefined |
| } |
|
|
| if (sourceUrl.startsWith('data:')) { |
| let buffer: dataUriToBuffer.MimeBuffer |
|
|
| try { |
| buffer = dataUriToBuffer(sourceUrl) |
| } catch (error) { |
| throw new Error(`Failed to parse source map URL for ${filename}.`, { |
| cause: error, |
| }) |
| } |
|
|
| if (buffer.type !== 'application/json') { |
| throw new Error( |
| `Unknown source map type for ${filename}: ${buffer.typeFull}.` |
| ) |
| } |
|
|
| try { |
| return JSON.parse(buffer.toString()) |
| } catch (error) { |
| throw new Error(`Failed to parse source map for ${filename}.`, { |
| cause: error, |
| }) |
| } |
| } |
|
|
| const sourceMapFilename = path.resolve( |
| path.dirname(filename), |
| decodeURIComponent(sourceUrl) |
| ) |
|
|
| try { |
| const sourceMapContents = await fs.readFile(sourceMapFilename, 'utf-8') |
|
|
| return JSON.parse(sourceMapContents.toString()) |
| } catch (error) { |
| throw new Error(`Failed to parse source map ${sourceMapFilename}.`, { |
| cause: error, |
| }) |
| } |
| } |
|
|
