fix: can send FormData with File. (#16576)

2026-04-28 19:00:03 -05:00 · 2021-05-24 23:07:44 +09:00
parent c4aaa58744
commit c2588798a0
4 changed files with 82 additions and 1 deletions
@@ -499,6 +499,32 @@ describe('src/cy/commands/request', () => {
          expect(dec.decode(response.body)).to.contain('1,2,3,4')
        })
      })
+
+      it('can send FormData with File', () => {
+        const formData = new FormData()
+
+        formData.set('file', new File(['1,2,3,4'], 'upload.txt'), 'upload.txt')
+        formData.set('name', 'Tony Stark')
+        cy.request({
+          method: 'POST',
+          url: 'http://localhost:3500/dump-form-data',
+          body: formData,
+          headers: {
+            'content-type': 'multipart/form-data',
+          },
+        })
+        .then((response) => {
+          expect(response.status).to.equal(200)
+          // When user-passed body to the Nodejs server is a Buffer,
+          // Nodejs doesn't provide any decoder in the response.
+          // So, we need to decode it ourselves.
+          const dec = new TextDecoder()
+          const result = dec.decode(response.body)
+
+          expect(result).to.contain('Tony Stark')
+          expect(result).to.contain('upload.txt')
+        })
+      })
    })

    describe('subjects', () => {
@@ -6,6 +6,8 @@ const http = require('http')
 const httpsProxy = require('@packages/https-proxy')
 const path = require('path')
 const Promise = require('bluebird')
+const multer = require('multer')
+const upload = multer({ dest: 'cypress/_test-output/' })

 const PATH_TO_SERVER_PKG = path.dirname(require.resolve('@packages/server'))
 const httpPorts = [3500, 3501]
@@ -144,6 +146,10 @@ const createApp = (port) => {
    return res.send(`<html><body>it worked!<br>request body:<br>${req.body.toString()}</body></html>`)
  })

+  app.all('/dump-form-data', upload.single('file'), (req, res) => {
+    return res.send(`<html><body>it worked!<br>request body:<br>${JSON.stringify(req.body)}<br>original name:<br>${req.file.originalname}</body></html>`)
+  })
+
  app.get('/status-404', (req, res) => {
    return res
    .status(404)
@@ -59,6 +59,7 @@
    "minimist": "1.2.5",
    "mocha": "7.0.1",
    "morgan": "1.9.1",
+    "multer": "1.4.2",
    "ordinal": "1.0.3",
    "react-15.6.1": "npm:react@15.6.1",
    "react-16.0.0": "npm:react@16.0.0",
@@ -282,13 +282,61 @@ module.exports = (Commands, Cypress, cy, state, config) => {
        // Check if body is Blob.
        // construct.name is added because the parent of the Blob is not the same Blob
        // if it's generated from the test spec code.
-        if (requestOpts.body instanceof Blob || requestOpts?.body?.constructor.name === 'Blob') {
+        if (requestOpts.body instanceof Blob || requestOpts.body?.constructor.name === 'Blob') {
          requestOpts.bodyIsBase64Encoded = true

          return Cypress.Blob.blobToBase64String(requestOpts.body).then((str) => {
            requestOpts.body = str
          })
        }
+
+        // https://github.com/cypress-io/cypress/issues/1647
+        // Handle if body is FormData
+        if (requestOpts.body instanceof FormData || requestOpts.body?.constructor.name === 'FormData') {
+          const boundary = '----CypressFormDataBoundary'
+
+          // reset content-type
+          if (requestOpts.headers) {
+            delete requestOpts.headers[Object.keys(requestOpts).find((key) => key.toLowerCase() === 'content-type')]
+          } else {
+            requestOpts.headers = {}
+          }
+
+          // boundary is required for form data
+          // @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Methods/POST
+          requestOpts.headers['content-type'] = `multipart/form-data; boundary=${boundary}`
+
+          // socket.io ignores FormData.
+          // So, we need to encode the data into base64 string format.
+          const formBody = []
+
+          requestOpts.body.forEach((value, key) => {
+            // HTTP line break style is \r\n.
+            // @see https://stackoverflow.com/questions/5757290/http-header-line-break-style
+            if (value instanceof File || value?.constructor.name === 'File') {
+              formBody.push(`--${boundary}\r\n`)
+              formBody.push(`Content-Disposition: form-data; name="${key}"; filename="${value.name}"\r\n`)
+              formBody.push(`Content-Type: ${value.type || 'application/octet-stream'}\r\n`)
+              formBody.push('\r\n')
+              formBody.push(value)
+              formBody.push('\r\n')
+            } else {
+              formBody.push(`--${boundary}\r\n`)
+              formBody.push(`Content-Disposition: form-data; name="${key}"\r\n`)
+              formBody.push('\r\n')
+              formBody.push(value)
+              formBody.push('\r\n')
+            }
+          })
+
+          formBody.push(`--${boundary}--\r\n`)
+
+          requestOpts.bodyIsBase64Encoded = true
+
+          return Cypress.Blob.blobToBase64String(new Blob(formBody)).then((str) => {
+            requestOpts.body = str
+          })
+        }
      })
      .then(() => {
        return Cypress.backend('http:request', requestOpts)