chore: allow any JSON object to be saved in blob store (#901)

The blob store will need to store additional metadata, such as audio
duration, in the future. This changes its `metadata` type to any JSON
object to allow this.

It also adds a test for `blobStore.entry()` to ensure metadata is saved.

This change shouldn't affect the external API because the blob store is
not directly exposed. It's used internally by `BlobApi`, which did not
change.

src/blob-store/index.js

@@ -4,6 +4,7 @@ import util from 'node:util'
 import { discoveryKey } from 'hypercore-crypto'
 import { TypedEmitter } from 'tiny-typed-emitter'
 import { LiveDownload } from './live-download.js'
+/** @import { JsonObject } from 'type-fest' */
 /** @import { Readable as NodeReadable } from 'node:stream' */
 /** @import { Readable as StreamxReadable, Writable } from 'streamx' */
 /** @import { BlobId } from '../types.js' */
@@ -200,7 +201,7 @@ export class BlobStore {
    * @param {Omit<BlobId, 'driveId'>} blobId
    * @param {Buffer} blob
    * @param {object} [options]
-   * @param {{mimeType: string}} [options.metadata] Metadata to store with the blob
+   * @param {JsonObject} [options.metadata] Metadata to store with the blob
    * @returns {Promise<string>} discovery key as hex string of hyperdrive where blob is stored
    */
   async put({ type, variant, name }, blob, options) {
@@ -212,7 +213,7 @@ export class BlobStore {
   /**
    * @param {Omit<BlobId, 'driveId'>} blobId
    * @param {object} [options]
-   * @param {{mimeType: string}} [options.metadata] Metadata to store with the blob
+   * @param {JsonObject} [options.metadata] Metadata to store with the blob
    * @returns {Writable & { driveId: string }}
    */
   createWriteStream({ type, variant, name }, options) {

src/fastify-plugins/blobs.js

@@ -102,6 +102,7 @@ async function routes(fastify, options) {
       // Extract the 'mimeType' property of the metadata and use it for the response header if found
       if (
         metadata &&
+        typeof metadata === 'object' &&
         'mimeType' in metadata &&
         typeof metadata.mimeType === 'string'
       ) {

test/blob-store/blob-store.js

@@ -153,6 +153,32 @@ test('blobStore.createWriteStream(blobId) and blobStore.createReadStream(blobId)
   assert.deepEqual(bndlbuf, diskbuf, 'should be equal')
 })
 
+test('blobStore.entry includes metadata if present', async () => {
+  const { blobStore } = testenv()
+
+  const blobId = /** @type {const} */ ({
+    type: 'photo',
+    variant: 'original',
+    name: 'test-file',
+  })
+  const ws = blobStore.createWriteStream(blobId, {
+    metadata: {
+      foo: 'bar',
+      baz: [1, 2, 3],
+    },
+  })
+  await pipeline(fs.createReadStream(new URL(import.meta.url)), ws)
+
+  const entry = await blobStore.entry({
+    ...blobId,
+    driveId: ws.driveId,
+  })
+  assert.deepEqual(entry?.value.metadata, {
+    foo: 'bar',
+    baz: [1, 2, 3],
+  })
+})
+
 test('blobStore.createReadStream should not wait', async () => {
   const { blobStore } = testenv()
   const expected = await readFile(new URL(import.meta.url))

types/hyperdrive.d.ts

@@ -4,6 +4,7 @@ declare module 'hyperdrive' {
   import Hyperblobs, { BlobId } from 'hyperblobs'
   import { Readable, Writable } from 'streamx'
   import { TypedEmitter } from 'tiny-typed-emitter'
+  import { JsonValue } from 'type-fest'
 
   interface HyperdriveOptions {
     onwait: () => void
@@ -39,7 +40,7 @@ declare module 'hyperdrive' {
         executable: boolean // whether the blob at path is an executable
         linkname: null | string // if entry not symlink, otherwise a string to the entry this links to
         blob: BlobId // a Hyperblob id that can be used to fetch the blob associated with this entry
-        metadata: null | object
+        metadata: JsonValue
       }
     }
   }