feat: support upload note image api

nodejs/README.md

@@ -117,6 +117,23 @@ const updatedNote = await client.getNote('note-id', { etag })
 // If the note hasn't changed, the response will have status 304
 ```
 
+### Image Upload
+
+Upload an image to a note with `uploadNoteImage`. The API returns the uploaded image link in `data.link`.
+
+```javascript
+// Browser: pass a File from an <input type="file">
+const uploaded = await client.uploadNoteImage('note-id', file)
+console.log(uploaded.data.link)
+
+// Node.js 18+: pass a Blob and optional filename
+const image = new Blob([imageBuffer], { type: 'image/png' })
+const uploadedFromNode = await client.uploadNoteImage('note-id', image, {
+  filename: 'diagram.png'
+})
+console.log(uploadedFromNode.data.link)
+```
+
 ## API
 
 See the [code](./src/index.ts) and [typings](./src/type.ts). The API client is written in TypeScript, so you can get auto-completion and type checking in any TypeScript Language Server powered editor or IDE.
@@ -143,7 +160,7 @@ npm run test:e2e
 
 Set `HACKMD_E2E_MUTATIONS=1` to run write tests against your account:
 
-- **Notes:** create → get → update (title, content, tags) → list → delete.
+- **Notes:** create → get → update (title, content, tags) → upload fixture image → list → delete.
 - **Folders:** one integration test runs create (root + nested) → get → update → list → folder-order round-trip (skipped if that API returns 404) → delete. If **POST `/folders`** returns 404 (common before full production rollout), the test exits early with a warning; use staging or `HACKMD_E2E_FOLDERS=0`.
 
 ```bash

nodejs/src/index.ts

@@ -26,6 +26,8 @@ import {
   UpdateFolderOrderBody,
   UpdateTeamFolderBody,
   UpdateUserFolderBody,
+  UploadNoteImageOptions,
+  UploadNoteImageResponse,
 } from './type'
 import * as HackMDErrors from './error'
 
@@ -70,9 +72,6 @@ export class API {
 
     this.axios = axios.create({
       baseURL: hackmdAPIEndpointURL,
-      headers:{
-        "Content-Type": "application/json",
-      },
       timeout: options.timeout
     })
 
@@ -209,6 +208,16 @@ export class API {
     return this.unwrapData(this.axios.delete<SingleNote>(`notes/${noteId}`), options.unwrapData) as unknown as OptionReturnType<Opt, SingleNote>
   }
 
+  async uploadNoteImage<Opt extends UploadNoteImageOptions> (noteId: string, image: Blob, options = defaultOption as Opt): Promise<OptionReturnType<Opt, UploadNoteImageResponse>> {
+    const formData = new FormData()
+    formData.append('image', image, options.filename ?? undefined)
+
+    return this.unwrapData(
+      this.axios.post<UploadNoteImageResponse>(`notes/${noteId}/images`, formData),
+      options.unwrapData,
+    ) as unknown as OptionReturnType<Opt, UploadNoteImageResponse>
+  }
+
   async getTeams<Opt extends RequestOptions> (options = defaultOption as Opt): Promise<OptionReturnType<Opt, GetUserTeams>> {
     return this.unwrapData(this.axios.get<GetUserTeams>("teams"), options.unwrapData) as unknown as OptionReturnType<Opt, GetUserTeams>
   }

nodejs/src/type.ts

@@ -114,6 +114,17 @@ export type CreateUserNote = SingleNote
 export type UpdateUserNote = void
 export type DeleteUserNote = void
 
+export type UploadNoteImageResponse = {
+  data: {
+    link: string
+  }
+}
+
+export type UploadNoteImageOptions = {
+  unwrapData?: boolean
+  filename?: string
+}
+
 // Teams
 export type GetUserTeams = Team[]
 

nodejs/tests/api.spec.ts

@@ -143,6 +143,41 @@ test('updateFolderOrder sends order payload', async () => {
   })
 })
 
+test('uploadNoteImage sends image as multipart form data', async () => {
+  let uploaded: FormDataEntryValue | null = null
+  let contentType: string | null = null
+
+  server.use(
+    http.post('https://api.hackmd.io/v1/notes/test-note-id/images', async ({ request }) => {
+      contentType = request.headers.get('content-type')
+      const formData = await request.formData()
+      uploaded = formData.get('image')
+
+      return HttpResponse.json({
+        data: {
+          link: 'https://hackmd.io/_uploads/test-image.png',
+        },
+      })
+    }),
+  )
+
+  const response = await client.uploadNoteImage(
+    'test-note-id',
+    new Blob(['test image'], { type: 'image/png' }),
+    { filename: 'test-image.png' },
+  )
+
+  expect(contentType).toContain('multipart/form-data')
+  expect(uploaded).toBeInstanceOf(Blob)
+  const uploadedBlob = uploaded as unknown as Blob
+  expect(uploadedBlob.type).toBe('image/png')
+  expect(response).toEqual({
+    data: {
+      link: 'https://hackmd.io/_uploads/test-image.png',
+    },
+  })
+})
+
 test('should support updating team note title and tags metadata', async () => {
   const updatedTags = ['team', 'metadata']
   let requestBody: unknown

nodejs/tests/e2e/api.e2e.spec.ts

@@ -1,3 +1,4 @@
+import { readFileSync } from 'fs'
 import type { ApiFolderOrder } from '../../src'
 import { API } from '../../src'
 import { HttpResponseError } from '../../src/error'
@@ -144,6 +145,19 @@ describe('HackMD API (live e2e)', () => {
         }
       })
 
+      it('uploadNoteImage uploads an image to the note', async () => {
+        const image = readFileSync('tests/fixtures/hackmd-cute-logo.png')
+
+        const uploaded = await client.uploadNoteImage(
+          noteId,
+          new Blob([new Uint8Array(image)], { type: 'image/png' }),
+          { filename: `hackmd-cute-logo-${stamp}.png` },
+        )
+
+        expect(uploaded.data.link).toEqual(expect.any(String))
+        expect(uploaded.data.link.length).toBeGreaterThan(0)
+      })
+
       it('getNoteList includes the note', async () => {
         const list = await client.getNoteList()
         const found = list.find(n => n.id === noteId)