Extract AttachmentUpload

app/javascript/activetext/attachment_upload.js

@@ -0,0 +1,45 @@
+import { DirectUpload } from "activestorage"
+
+export class AttachmentUpload {
+  constructor(attachment, element) {
+    this.attachment = attachment
+    this.element = element
+    this.directUpload = new DirectUpload(attachment.file, this.directUploadUrl, this)
+  }
+
+  start() {
+    this.directUpload.create(this.directUploadDidComplete.bind(this))
+  }
+
+  directUploadWillStoreFileWithXHR(xhr) {
+    xhr.upload.addEventListener("progress", event => {
+      const progress = event.loaded / event.total * 100
+      this.attachment.setUploadProgress(progress)
+    })
+  }
+
+  directUploadDidComplete(error, attributes) {
+    if (error) {
+      throw new Error(`Direct upload failed: ${error}`)
+    }
+
+    this.attachment.setAttributes({
+      sgid: attributes.attachable_sgid,
+      url: this.createBlobUrl(attributes.signed_id, attributes.filename)
+    })
+  }
+
+  createBlobUrl(signedId, filename) {
+    return this.blobUrlTemplate
+      .replace(":signed_id", signedId)
+      .replace(":filename", encodeURIComponent(filename))
+  }
+
+  get directUploadUrl() {
+    return this.element.dataset.directUploadUrl
+  }
+
+  get blobUrlTemplate() {
+    return this.element.dataset.blobUrlTemplate
+  }
+}

app/javascript/activetext/index.js

@@ -1,34 +1,11 @@
 import * as Trix from "trix"
-import { DirectUpload } from "activestorage"
+import { AttachmentUpload } from "./attachment_upload"
 
 addEventListener("trix-attachment-add", event => {
-  const { attachment } = event
-  if (!attachment.file) return
+  const { attachment, target } = event
 
-  const { directUploadUrl, blobUrlTemplate } = event.target.dataset
-
-  const delegate = {
-    directUploadWillStoreFileWithXHR: (xhr) => {
-      xhr.upload.addEventListener("progress", event => {
-        const progress = event.loaded / event.total * 100
-        attachment.setUploadProgress(progress)
-      })
+  if (attachment.file) {
+    const upload = new AttachmentUpload(attachment, target)
+    upload.start()
   }
-  }
-
-  const directUpload = new DirectUpload(attachment.file, directUploadUrl, delegate)
-
-  directUpload.create((error, attributes) => {
-    if (error) {
-      console.warn("Failed to store file for attachment", attachment, error)
-    } else {
-      const sgid = attributes.attachable_sgid
-
-      const url = blobUrlTemplate
-        .replace(":signed_id", attributes.signed_id)
-        .replace(":filename", encodeURIComponent(attributes.filename))
-
-      attachment.setAttributes({ sgid, url })
-    }
-  })
 })