examples: add SHA256 checksum to uploads

examples/aws-nodejs/index.js

@@ -13,6 +13,11 @@ const port = process.env.PORT ?? 8080
 const accessControlAllowOrigin = '*' // You should define the actual domain(s) that are allowed to make requests.
 const bodyParser = require('body-parser')
 
+const unhoistableHeaders = new Set([
+  'x-amz-sdk-checksum-algorithm',
+  'x-amz-checksum-sha256',
+])
+
 const {
   S3Client,
   AbortMultipartUploadCommand,
@@ -109,16 +114,24 @@ const signOnServer = (req, res, next) => {
   // For the sake of simplification, we skip that check in this example.
 
   const Key = `${crypto.randomUUID()}-${req.body.filename}`
-  const { contentType } = req.body
+  const { contentType, ChecksumSHA256 } = req.body
 
   getSignedUrl(
     getS3Client(),
     new PutObjectCommand({
       Bucket: process.env.COMPANION_AWS_BUCKET,
       Key,
       ContentType: contentType,
+      ChecksumAlgorithm: 'SHA256',
+      ChecksumSHA256,
     }),
-    { expiresIn },
+    {
+      expiresIn,
+      // If not supplied, the presigner moves all the AWS-specific headers
+      // (starting with `x-amz-`) to the request query string.
+      // If supplied, these headers remain in the presigned request's header.
+      unhoistableHeaders,
+    },
   ).then((url) => {
     res.setHeader('Access-Control-Allow-Origin', accessControlAllowOrigin)
     res.json({
@@ -152,6 +165,7 @@ app.post('/s3/multipart', (req, res, next) => {
     Key,
     ContentType: type,
     Metadata: metadata,
+    ChecksumAlgorithm: 'SHA256',
   }
 
   const command = new CreateMultipartUploadCommand(params)
@@ -176,7 +190,7 @@ function validatePartNumber(partNumber) {
 }
 app.get('/s3/multipart/:uploadId/:partNumber', (req, res, next) => {
   const { uploadId, partNumber } = req.params
-  const { key } = req.query
+  const { key, sha256 } = req.query
 
   if (!validatePartNumber(partNumber)) {
     return res
@@ -201,12 +215,20 @@ app.get('/s3/multipart/:uploadId/:partNumber', (req, res, next) => {
       Key: key,
       UploadId: uploadId,
       PartNumber: partNumber,
-      Body: '',
+      ChecksumSHA256: sha256,
     }),
-    { expiresIn },
+    {
+      expiresIn,
+      // If not supplied, the presigner moves all the AWS-specific headers
+      // (starting with `x-amz-`) to the request query string.
+      // If supplied, these headers remain in the presigned request's header.
+      unhoistableHeaders,
+    },
   ).then((url) => {
     res.setHeader('Access-Control-Allow-Origin', accessControlAllowOrigin)
-    res.json({ url, expires: expiresIn })
+    res.json({ url, expires: expiresIn, headers: {
+      'x-amz-checksum-sha256': sha256,
+    } })
   }, next)
 })
 
@@ -264,7 +286,12 @@ app.post('/s3/multipart/:uploadId/complete', (req, res, next) => {
   const client = getS3Client()
   const { uploadId } = req.params
   const { key } = req.query
-  const { parts } = req.body
+
+  const parts = Array.from(req.body.parts[0].ETag, (ETag, i) => ({
+    ETag,
+    PartNumber: req.body.parts[0].PartNumber[i],
+    ChecksumSHA256: req.body.parts[0].ChecksumSHA256[i],
+  }))
 
   if (typeof key !== 'string') {
     return res

examples/aws-nodejs/public/withCustomEndpoints.html

@@ -43,7 +43,18 @@ <h1>AWS upload example</h1>
         // return JSON.stringify(data)
         // You'd also have to add `Content-Type` header with value `application/json`.
       }
+      async function computeHash(blob) {
+        const hashBuffer = await crypto.subtle.digest(
+          'SHA-256',
+          await blob.arrayBuffer(),
+        )
+        const stringifiedHash = String.fromCharCode(
+          ...new Uint8Array(hashBuffer),
+        )
+        return btoa(stringifiedHash)
+      }
       {
+        const cache = Object.create(null)
         const MiB = 0x10_00_00
 
         const uppy = new Uppy()
@@ -55,18 +66,7 @@ <h1>AWS upload example</h1>
             id: 'myAWSPlugin',
 
             // Files that are more than 100MiB should be uploaded in multiple parts.
-            shouldUseMultipart: (file) => file.size > 100 * MiB,
-
-            /**
-             * This method tells Uppy how to retrieve a temporary token for signing on the client.
-             * Signing on the client is optional, you can also do the signing from the server.
-             */
-            async getTemporarySecurityCredentials({ signal }) {
-              const response = await fetch('/s3/sts', { signal })
-              if (!response.ok)
-                throw new Error('Unsuccessful request', { cause: response })
-              return response.json()
-            },
+            shouldUseMultipart: true,
 
             // ========== Non-Multipart Uploads ==========
 
@@ -76,13 +76,7 @@ <h1>AWS upload example</h1>
              * you don't need to implement it.
              */
             async getUploadParameters(file, options) {
-              if (typeof crypto?.subtle === 'object') {
-                // If WebCrypto is available, let's do signing from the client.
-                return uppy
-                  .getPlugin('myAWSPlugin')
-                  .createSignedURL(file, options)
-              }
-
+              const ChecksumSHA256 = await computeHash(file.data)
               // Send a request to our Express.js signing endpoint.
               const response = await fetch('/s3/sign', {
                 method: 'POST',
@@ -92,6 +86,7 @@ <h1>AWS upload example</h1>
                 body: serialize({
                   filename: file.name,
                   contentType: file.type,
+                  ChecksumSHA256,
                 }),
                 signal: options.signal,
               })
@@ -110,6 +105,8 @@ <h1>AWS upload example</h1>
                 // Provide content type header required by S3
                 headers: {
                   'Content-Type': file.type,
+                  'x-amz-checksum-sha256': ChecksumSHA256,
+                  'x-amz-sdk-checksum-algorithm': 'SHA256',
                 },
               }
             },
@@ -170,14 +167,7 @@ <h1>AWS upload example</h1>
             },
 
             async signPart(file, options) {
-              if (typeof crypto?.subtle === 'object') {
-                // If WebCrypto, let's do signing from the client.
-                return uppy
-                  .getPlugin('myAWSPlugin')
-                  .createSignedURL(file, options)
-              }
-
-              const { uploadId, key, partNumber, signal } = options
+              const { uploadId, key, partNumber, signal, body } = options
 
               signal?.throwIfAborted()
 
@@ -186,10 +176,12 @@ <h1>AWS upload example</h1>
                   'Cannot sign without a key, an uploadId, and a partNumber',
                 )
               }
+              const sha256 = await computeHash(body)
+              cache[uploadId + partNumber] = sha256
 
               const filename = encodeURIComponent(key)
               const response = await fetch(
-                `/s3/multipart/${uploadId}/${partNumber}?key=${filename}`,
+                `/s3/multipart/${uploadId}/${partNumber}?key=${filename}&sha256=${encodeURIComponent(sha256)}`,
                 { signal },
               )
 
@@ -234,7 +226,13 @@ <h1>AWS upload example</h1>
                   headers: {
                     accept: 'application/json',
                   },
-                  body: serialize({ parts }),
+                  body: serialize({
+                    parts: parts.map(({ ETag, PartNumber }) => {
+                      const ChecksumSHA256 = cache[uploadId + PartNumber]
+                      delete cache[uploadId + PartNumber]
+                      return { ETag, PartNumber, ChecksumSHA256 }
+                    }),
+                  }),
                   signal,
                 },
               )