Modern OpenAPI parser written in TypeScript with support for OpenAPI 3.1, OpenAPI 3.0 and Swagger 2.0.
- [x] Written in TypeScript
- [x] Runs in Node.js and in the browser (without any polyfills or configuration)
- [x] Tested with hundreds of real world examples
- [ ] Amazing error output
- [ ] Support for OpenAPI 4.0 👀
npm add @scalar/openapi-parser
import { validate } from '@scalar/openapi-parser'
const file = `{
"openapi": "3.1.0",
"info": {
"title": "Hello World",
"version": "1.0.0"
},
"paths": {}
}`
const { valid, errors } = await validate(file)
console.log(valid)
if (!valid) {
console.log(errors)
}
import { dereference } from '@scalar/openapi-parser'
const specification = `{
"openapi": "3.1.0",
"info": {
"title": "Hello World",
"version": "1.0.0"
},
"paths": {}
}`
const { schema, errors } = await dereference(specification)
The dereference
function accepts an onDereference
callback option that gets called whenever a reference is resolved. This can be useful for tracking which schemas are being dereferenced:
import { dereference } from '@scalar/openapi-parser'
const { schema, errors } = await dereference(specification, {
onDereference: ({ schema, ref }) => {
//
},
})
import { filter } from '@scalar/openapi-parser'
const specification = `{
"openapi": "3.1.0",
"info": {
"title": "Hello World",
"version": "1.0.0"
},
"paths": {}
}`
const { specification } = filter(specification, (schema) => !schema?.['x-internal'])
There’s an upgrade
command to upgrade all your OpenAPI documents to the latest OpenAPI version.
⚠️ The upgrade from Swagger 2.0 is still experimental and probably lacks features.
import { upgrade } from '@scalar/openapi-parser'
const { specification } = upgrade({
swagger: '2.0',
info: {
title: 'Hello World',
version: '1.0.0',
},
paths: {},
})
console.log(specification.openapi)
// Output: 3.1.0
The sanitize()
utility helps ensure your OpenAPI document is valid and complete.
It automatically adds any missing required properties like the OpenAPI version and info object, collects operation tags
and adds them to the global tags array and normalizes security scheme types.
This makes your document as OpenAPI-compliant as possible with minimal effort, handling many common specification requirements automatically.
⚠️ This doesn’t support Swagger 2.0 documents.
import { sanitize } from '@scalar/openapi-parser'
const result = sanitize({
info: {
title: 'Hello World',
},
})
console.log(result)
import { openapi } from '@scalar/openapi-parser'
const specification = …
// New pipeline …
const result = openapi()
// loads the specification …
.load(specification)
// upgrades to OpenAPI 3.1 …
.upgrade()
// removes all internal operations …
.filter((schema) => !schema?.['x-internal'])
// done!
.get()
If you’re more the then/catch type of guy, that’s fine:
import { validate } from '@scalar/openapi-parser'
const specification = …
validate(specification, {
throwOnError: true,
})
.then(result => {
// Success
})
.catch(error => {
// Failure
})
If you just look for our types, you can install the package separately:
npm add @scalar/openapi-types
And use it like this:
import type { OpenAPI } from '@scalar/openapi-types'
const file: OpenAPI.Document = {
openapi: '3.1.0',
info: {
title: 'Hello World',
version: '1.0.0',
},
paths: {},
}
You can reference other files, too. To do that, the parser needs to know what files are available.
import { dereference, load } from '@scalar/openapi-parser'
import { fetchUrls } from '@scalar/openapi-parser/plugins/fetch-urls'
import { readFiles } from '@scalar/openapi-parser/plugins/read-files'
// Load a file and all referenced files
const { filesystem } = await load('./openapi.yaml', {
plugins: [
readFiles(),
fetchUrls({
limit: 5,
}),
],
})
// Instead of just passing a single specification, pass the whole “filesystem”
const result = await dereference(filesystem)
As you see, load()
supports plugins. You can write your own plugin, if you’d like to fetch API defintions from another data source, for example your database. Look at the source code of the readFiles
to learn how this could look like.
Once the fetchUrls
plugin is loaded, you can also just pass an URL:
import { dereference, load } from '@scalar/openapi-parser'
import { fetchUrls } from '@scalar/openapi-parser/plugins/fetch-urls'
// Load a file and all referenced files
const { filesystem } = await load(
'https://cdn.jsdelivr.net/npm/@scalar/galaxy/dist/latest.yaml',
{
plugins: [fetchUrls()],
},
)
If you’re using the package in a browser environment, you may run into CORS issues when fetching from URLs. You can intercept the requests, for example to use a proxy, though:
import { dereference, load } from '@scalar/openapi-parser'
import { fetchUrls } from '@scalar/openapi-parser/plugins/fetch-urls'
// Load a file and all referenced files
const { filesystem } = await load(
'https://cdn.jsdelivr.net/npm/@scalar/galaxy/dist/latest.yaml',
{
plugins: [
fetchUrls({
fetch: (url) => fetch(url.replace('BANANA.net', 'jsdelivr.net')),
}).get('https://cdn.BANANA.net/npm/@scalar/galaxy/dist/latest.yaml'),
],
},
)
We are API nerds. You too? Let’s chat on Discord: https://discord.gg/scalar
Thanks a ton for all the help and inspiration:
- @philsturgeon to make sure we build something we won’t hate.
- We took a lot of inspiration from @seriousme and his package openapi-schema-validator early-on.
- You could consider this package the modern successor of @apidevtools/swagger-parser, we even test against it to make sure we’re getting the same results (where intended).
- We stole a lot of example specification from @mermade to test against.
The source code in this repository is licensed under MIT.