Depseek NPM | npm.io

depseek

Seeks for dependency references in JS/TS code

Motivation

Dep extraction is a common task for many tools solved in different ways from regexps to AST parsing. This implementation relies on streams to make controllable memory consumption.

Status

Working draft

Key features

Uses stream-based reader
Points exact dependency references by offset
Handles string literal and comments
Captures bound comments (optional)

Usage

npm i depseek

Usage

import fs from 'fs'
import {depseek} from 'depseek'

const stream = fs.createReadStream('index.js')
const deps = await depseek(stream)

// returns
[
  { type: 'dep', value: 'node:fs', index: 17 },
  { type: 'dep', value: 'foo', index: 34 },
  { type: 'dep', value: 'q', index: 92 }
  // ...
]

Options

By default depseek extracts only require and import arguments. You can also capture bound comments.

const depsAndComments = await depseek(stream, {comments: true})

[
  { type: 'dep', value: 'node:fs', index: 17 },
  { type: 'dep', value: 'foo', index: 34 },
  { type: 'comment', value: ' @1.0.0', index: 46 }
  //...
]

Stream buffer size set to 1000 by default. You can change the limit by passing bufferSize.

const deps = await depseek(stream, {bufferSize: 10000})

Sync

Streams are aimed at intensive bulk operations. If you need to process just a few files, you can use depseekSync.

import fs from 'node:fs'
import { depseekSync } from 'depseek'

const contents = fs.readFileSync('index.js', 'utf8') // Buffer or string
const deps = depseekSync(contents)

`patchRefs`

The one more utility is patchRefs that replaces dependency references with a given value.

import {patchRefs} from 'depseek'

const patcher = (v: string) => v.startsWith('.') ? v + '.js' : v
const input = `
import {foo} from './foo'
import {bar} from "./bar"
import {baz} from 'baz'
`

patchRefs(input, patcher)
// gives as a result:
`
import {foo} from './foo.js'
import {bar} from "./bar.js"
import {baz} from 'baz'
`