A full-featured
koa
body parser middleware. Supportsmultipart
,urlencoded
, andjson
request bodies. Provides the same functionality as Express's bodyParser -multer
.
Install with npm
npm install koa-body
- can handle requests such as:
- multipart/form-data
- application/x-www-form-urlencoded
- application/json
- application/json-patch+json
- application/vnd.api+json
- application/csp-report
- text/xml
- option for patch to Koa or Node, or either
- file uploads
- body, fields and files size limiting
npm install koa koa-body # Note that Koa requires Node.js 7.6.0+ for async/await support
index.js:
const Koa = require('koa');
const { koaBody } = require('koa-body');
const app = new Koa();
app.use(koaBody());
app.use((ctx) => {
ctx.body = `Request Body: ${JSON.stringify(ctx.request.body)}`;
});
app.listen(3000);
node index.js
curl -i https://localhost:3000/users -d "name=test"
Output:
HTTP/1.1 200 OK
Content-Type: text/plain; charset=utf-8
Content-Length: 29
Date: Wed, 03 May 2017 02:09:44 GMT
Connection: keep-alive
Request Body: {"name":"test"}%
For a more comprehensive example, see examples/multipart.js
Usage with koa-router
It's generally better to only parse the body as needed, if using a router that supports middleware composition, we can inject it only for certain routes.
const Koa = require('koa');
const app = new Koa();
const router = require('koa-router')();
const { koaBody } = require('koa-body');
router.post('/users', koaBody(), (ctx) => {
console.log(ctx.request.body);
// => POST body
ctx.body = JSON.stringify(ctx.request.body);
});
app.use(router.routes());
app.listen(3000);
console.log('curl -i https://localhost:3000/users -d "name=test"');
For unsupported text body type, for example, text/xml
, you can use the unparsed request body at ctx.request.body
. For the text content type, the includeUnparsed
setting is not required.
// xml-parse.js:
const Koa = require('koa');
const { koaBody } = require('koa-body');
const convert = require('xml-js');
const app = new Koa();
app.use(koaBody());
app.use((ctx) => {
const obj = convert.xml2js(ctx.request.body);
ctx.body = `Request Body: ${JSON.stringify(obj)}`;
});
app.listen(3000);
node xml-parse.js
curl -i https://localhost:3000/users -H "Content-Type: text/xml" -d '<?xml version="1.0"?><catalog id="1"></catalog>'
Output:
HTTP/1.1 200 OK
Content-Type: text/plain; charset=utf-8
Content-Length: 135
Date: Tue, 09 Jun 2020 11:17:38 GMT
Connection: keep-alive
Request Body: {"declaration":{"attributes":{"version":"1.0"}},"elements":[{"type":"element","name":"catalog","attributes":{"id":"1"}}]}%
Options available for
koa-body
. Four custom options, and others are fromraw-body
andformidable
.
patchNode
{Boolean} Patch request body to Node'sctx.req
, defaultfalse
patchKoa
{Boolean} Patch request body to Koa'sctx.request
, defaulttrue
jsonLimit
{String|Integer} The byte (if integer) limit of the JSON body, default1mb
formLimit
{String|Integer} The byte (if integer) limit of the form body, default56kb
textLimit
{String|Integer} The byte (if integer) limit of the text body, default56kb
encoding
{String} Sets encoding for incoming form fields, defaultutf-8
multipart
{Boolean} Parse multipart bodies, defaultfalse
urlencoded
{Boolean} Parse urlencoded bodies, defaulttrue
text
{Boolean} Parse text bodies, such as XML, defaulttrue
json
{Boolean} Parse JSON bodies, defaulttrue
jsonStrict
{Boolean} Toggles co-body strict mode; if set to true - only parses arrays or objects, defaulttrue
includeUnparsed
{Boolean} Toggles co-body returnRawBody option; if set to true, for form encoded and JSON requests the raw, unparsed request body will be attached toctx.request.body
using aSymbol
(see details), defaultfalse
formidable
{Object} Options to pass to the formidable multipart parseronError
{Function} Custom error handle, if throw an error, you can customize the response - onError(error, context), default will throwparsedMethods
{String[]} Declares the HTTP methods where bodies will be parsed, default['POST', 'PUT', 'PATCH']
. Replacesstrict
option.
see https://tools.ietf.org/html/draft-ietf-httpbis-p2-semantics-19#section-6.3
GET
,HEAD
, andDELETE
requests have no defined semantics for the request body, but this doesn't mean they may not be valid in certain use cases.- koa-body is strict by default, parsing only
POST
,PUT
, andPATCH
requests - you may use either the enumeration or strings to chose which methods to parse: For example,
HttpMethodEnum.PATCH
Uploaded files are accessible via ctx.request.files
.
Some applications require cryptographic verification of request bodies, for example webhooks from slack or stripe. The unparsed body can be accessed if includeUnparsed
is true
in koa-body's options. When enabled, import the symbol for accessing the request body from unparsed = require('koa-body/unparsed.js')
, or define your own accessor using unparsed = Symbol.for('unparsedBody')
. Then the unparsed body is available using ctx.request.body[unparsed]
.
See node-formidable for a full list of options
maxFields
{Integer} Limits the number of fields that the querystring parser will decode, default1000
maxFieldsSize
{Integer} Limits the amount of memory all fields together (except files) can allocate in bytes. If this value is exceeded, an 'error' event is emitted, default2mb (2 * 1024 * 1024)
uploadDir
{String} Sets the directory for placing file uploads in, defaultos.tmpDir()
keepExtensions
{Boolean} Files written touploadDir
will include the extensions of the original files, defaultfalse
hashAlgorithm
{String} If you want checksums calculated for incoming files, set this to either'sha1'
or'md5'
, defaultfalse
multiples
{Boolean} Multiple file uploads or no, defaulttrue
onFileBegin
{Function} Special callback on file begin. The function is executed directly by formidable. It can be used to rename files before saving them to disk. See the docs
Please see the Changelog for a summary of changes.
$ npm test
The MIT License, 2014 Charlike Mike Reagent (@tunnckoCore) and Daryl Lau (@daryllau)