Upload to multiple servers, delete from servers when removing in dialog

Introduces a dedicated blossom service to tie everything together

app/components/place-photo-item.gjs

@@ -2,31 +2,17 @@ import Component from '@glimmer/component';
 import { tracked } from '@glimmer/tracking';
 import { inject as service } from '@ember/service';
 import { task } from 'ember-concurrency';
-import { EventFactory } from 'applesauce-core';
 import Icon from '#components/icon';
 import { on } from '@ember/modifier';
 import { fn } from '@ember/helper';
 
-const DEFAULT_BLOSSOM_SERVER = 'https://blossom.nostr.build';
-
-function bufferToHex(buffer) {
-  return Array.from(new Uint8Array(buffer))
-    .map((b) => b.toString(16).padStart(2, '0'))
-    .join('');
-}
-
 export default class PlacePhotoItem extends Component {
-  @service nostrAuth;
-  @service nostrData;
+  @service blossom;
 
   @tracked thumbnailUrl = '';
   @tracked error = '';
   @tracked isUploaded = false;
 
-  get blossomServer() {
-    return this.nostrData.blossomServers[0] || DEFAULT_BLOSSOM_SERVER;
-  }
-
   constructor() {
     super(...arguments);
     if (this.args.file) {
@@ -45,8 +31,6 @@ export default class PlacePhotoItem extends Component {
   uploadTask = task(async (file) => {
     this.error = '';
     try {
-      if (!this.nostrAuth.isConnected) throw new Error('Not connected');
-
       const dim = await new Promise((resolve) => {
         const img = new Image();
         img.onload = () => resolve(`${img.width}x${img.height}`);
@@ -54,65 +38,17 @@ export default class PlacePhotoItem extends Component {
         img.src = this.thumbnailUrl;
       });
 
-      const buffer = await file.arrayBuffer();
-      const hashBuffer = await crypto.subtle.digest('SHA-256', buffer);
-      const payloadHash = bufferToHex(hashBuffer);
-
-      let serverUrl = this.blossomServer;
-      if (serverUrl.endsWith('/')) {
-        serverUrl = serverUrl.slice(0, -1);
-      }
-      const uploadUrl = `${serverUrl}/upload`;
-
-      const factory = new EventFactory({ signer: this.nostrAuth.signer });
-      const now = Math.floor(Date.now() / 1000);
-      const serverHostname = new URL(serverUrl).hostname;
-
-      const authTemplate = {
-        kind: 24242,
-        created_at: now,
-        content: 'Upload photo for place',
-        tags: [
-          ['t', 'upload'],
-          ['x', payloadHash],
-          ['expiration', String(now + 3600)],
-          ['server', serverHostname],
-        ],
-      };
-
-      const authEvent = await factory.sign(authTemplate);
-      const base64 = btoa(JSON.stringify(authEvent));
-      const base64url = base64
-        .replace(/\+/g, '-')
-        .replace(/\//g, '_')
-        .replace(/=+$/, '');
-      const authHeader = `Nostr ${base64url}`;
-
-      // eslint-disable-next-line warp-drive/no-external-request-patterns
-      const response = await fetch(uploadUrl, {
-        method: 'PUT',
-        headers: {
-          Authorization: authHeader,
-          'X-SHA-256': payloadHash,
-        },
-        body: file,
-      });
-
-      if (!response.ok) {
-        const text = await response.text();
-        throw new Error(`Upload failed (${response.status}): ${text}`);
-      }
-
-      const result = await response.json();
+      const result = await this.blossom.upload(file);
       this.isUploaded = true;
 
       if (this.args.onSuccess) {
         this.args.onSuccess({
           file,
           url: result.url,
-          type: file.type,
+          fallbackUrls: result.fallbackUrls,
+          type: result.type,
           dim,
-          hash: payloadHash,
+          hash: result.hash,
         });
       }
     } catch (e) {

app/components/place-photo-upload.gjs

@@ -4,6 +4,7 @@ import { action } from '@ember/object';
 import { inject as service } from '@ember/service';
 import { on } from '@ember/modifier';
 import { EventFactory } from 'applesauce-core';
+import { task } from 'ember-concurrency';
 import Geohash from 'latlon-geohash';
 import PlacePhotoItem from './place-photo-item';
 import Icon from '#components/icon';
@@ -12,6 +13,8 @@ import { or, not } from 'ember-truth-helpers';
 export default class PlacePhotoUpload extends Component {
   @service nostrAuth;
   @service nostrRelay;
+  @service blossom;
+  @service toast;
 
   @tracked files = [];
   @tracked uploadedPhotos = [];
@@ -74,12 +77,26 @@ export default class PlacePhotoUpload extends Component {
 
   @action
   removeFile(fileToRemove) {
+    const photoData = this.uploadedPhotos.find((p) => p.file === fileToRemove);
     this.files = this.files.filter((f) => f !== fileToRemove);
     this.uploadedPhotos = this.uploadedPhotos.filter(
       (p) => p.file !== fileToRemove
     );
+
+    if (photoData && photoData.hash && photoData.url) {
+      this.deletePhotoTask.perform(photoData);
+    }
   }
 
+  deletePhotoTask = task(async (photoData) => {
+    try {
+      if (!photoData.hash) return;
+      await this.blossom.delete(photoData.hash);
+    } catch (e) {
+      this.toast.show(`Failed to delete photo from server: ${e.message}`, 5000);
+    }
+  });
+
   @action
   async publish() {
     if (!this.nostrAuth.isConnected) {
@@ -117,17 +134,21 @@ export default class PlacePhotoUpload extends Component {
       }
 
       for (const photo of this.uploadedPhotos) {
-        const imeta = [
-          'imeta',
-          `url ${photo.url}`,
-          `m ${photo.type}`,
-          'alt A photo of a place',
-        ];
+        const imeta = ['imeta', `url ${photo.url}`];
 
-        if (photo.dim) {
-          imeta.splice(3, 0, `dim ${photo.dim}`);
+        if (photo.fallbackUrls && photo.fallbackUrls.length > 0) {
+          for (const fallbackUrl of photo.fallbackUrls) {
+            imeta.push(`url ${fallbackUrl}`);
+          }
         }
 
+        imeta.push(`m ${photo.type}`);
+
+        if (photo.dim) {
+          imeta.push(`dim ${photo.dim}`);
+        }
+
+        imeta.push('alt A photo of a place');
         tags.push(imeta);
       }
 

app/services/blossom.js

@@ -0,0 +1,166 @@
+import Service, { inject as service } from '@ember/service';
+import { EventFactory } from 'applesauce-core';
+
+export const DEFAULT_BLOSSOM_SERVER = 'https://blossom.nostr.build';
+
+function bufferToHex(buffer) {
+  return Array.from(new Uint8Array(buffer))
+    .map((b) => b.toString(16).padStart(2, '0'))
+    .join('');
+}
+
+function getBlossomUrl(serverUrl, path) {
+  let url = serverUrl || DEFAULT_BLOSSOM_SERVER;
+  if (url.endsWith('/')) {
+    url = url.slice(0, -1);
+  }
+  return path.startsWith('/') ? `${url}${path}` : `${url}/${path}`;
+}
+
+export default class BlossomService extends Service {
+  @service nostrAuth;
+  @service nostrData;
+
+  get servers() {
+    const servers = this.nostrData.blossomServers;
+    return servers.length ? servers : [DEFAULT_BLOSSOM_SERVER];
+  }
+
+  async _getAuthHeader(action, hash, serverUrl) {
+    const factory = new EventFactory({ signer: this.nostrAuth.signer });
+    const now = Math.floor(Date.now() / 1000);
+    const serverHostname = new URL(serverUrl).hostname;
+
+    const authTemplate = {
+      kind: 24242,
+      created_at: now,
+      content: action === 'upload' ? 'Upload photo for place' : 'Delete photo',
+      tags: [
+        ['t', action],
+        ['x', hash],
+        ['expiration', String(now + 3600)],
+        ['server', serverHostname],
+      ],
+    };
+
+    const authEvent = await factory.sign(authTemplate);
+    const base64 = btoa(JSON.stringify(authEvent));
+    const base64url = base64
+      .replace(/\+/g, '-')
+      .replace(/\//g, '_')
+      .replace(/=+$/, '');
+    return `Nostr ${base64url}`;
+  }
+
+  async _uploadToServer(file, hash, serverUrl) {
+    const uploadUrl = getBlossomUrl(serverUrl, 'upload');
+    const authHeader = await this._getAuthHeader('upload', hash, serverUrl);
+
+    // eslint-disable-next-line warp-drive/no-external-request-patterns
+    const response = await fetch(uploadUrl, {
+      method: 'PUT',
+      headers: {
+        Authorization: authHeader,
+        'X-SHA-256': hash,
+      },
+      body: file,
+    });
+
+    if (!response.ok) {
+      const text = await response.text();
+      throw new Error(`Upload failed (${response.status}): ${text}`);
+    }
+
+    return response.json();
+  }
+
+  async upload(file) {
+    if (!this.nostrAuth.isConnected) throw new Error('Not connected');
+
+    const buffer = await file.arrayBuffer();
+    const hashBuffer = await crypto.subtle.digest('SHA-256', buffer);
+    const payloadHash = bufferToHex(hashBuffer);
+
+    const servers = this.servers;
+    const mainServer = servers[0];
+    const fallbackServers = servers.slice(1);
+
+    // Start all uploads concurrently
+    const mainPromise = this._uploadToServer(file, payloadHash, mainServer);
+    const fallbackPromises = fallbackServers.map((serverUrl) =>
+      this._uploadToServer(file, payloadHash, serverUrl)
+    );
+
+    // Main server MUST succeed
+    const mainResult = await mainPromise;
+
+    // Fallback servers can fail, but we log the warnings
+    const fallbackResults = await Promise.allSettled(fallbackPromises);
+    const fallbackUrls = [];
+
+    for (let i = 0; i < fallbackResults.length; i++) {
+      const result = fallbackResults[i];
+      if (result.status === 'fulfilled') {
+        fallbackUrls.push(result.value.url);
+      } else {
+        console.warn(
+          `Fallback upload to ${fallbackServers[i]} failed:`,
+          result.reason
+        );
+      }
+    }
+
+    return {
+      url: mainResult.url,
+      fallbackUrls,
+      hash: payloadHash,
+      type: file.type,
+    };
+  }
+
+  async _deleteFromServer(hash, serverUrl) {
+    const deleteUrl = getBlossomUrl(serverUrl, hash);
+    const authHeader = await this._getAuthHeader('delete', hash, serverUrl);
+
+    // eslint-disable-next-line warp-drive/no-external-request-patterns
+    const response = await fetch(deleteUrl, {
+      method: 'DELETE',
+      headers: {
+        Authorization: authHeader,
+      },
+    });
+
+    if (!response.ok) {
+      const text = await response.text();
+      throw new Error(text || response.statusText);
+    }
+  }
+
+  async delete(hash) {
+    if (!this.nostrAuth.isConnected) throw new Error('Not connected');
+
+    const servers = this.servers;
+    const mainServer = servers[0];
+    const fallbackServers = servers.slice(1);
+
+    const mainPromise = this._deleteFromServer(hash, mainServer);
+    const fallbackPromises = fallbackServers.map((serverUrl) =>
+      this._deleteFromServer(hash, serverUrl)
+    );
+
+    // Main server MUST succeed
+    await mainPromise;
+
+    // Fallback servers can fail, log warnings
+    const fallbackResults = await Promise.allSettled(fallbackPromises);
+    for (let i = 0; i < fallbackResults.length; i++) {
+      const result = fallbackResults[i];
+      if (result.status === 'rejected') {
+        console.warn(
+          `Fallback delete from ${fallbackServers[i]} failed:`,
+          result.reason
+        );
+      }
+    }
+  }
+}