Init

Author: Andy Leverenz

app/controllers/posts_controller.rb

@@ -0,0 +1,64 @@
+class PostsController < ApplicationController
+  before_action :authenticate_user!, except: [:show, :index]
+  before_action :set_post, only: [:show, :edit, :update, :destroy]
+
+
+  def index
+    @posts = Post.all
+  end
+
+  def show
+  end
+
+  def new
+    @post = Post.new
+  end
+
+  def edit
+  end
+
+  def create
+    @post = Post.new(post_params)
+    @post.user_id = current_user.id
+
+    respond_to do |format|
+      if @post.save
+        format.html { redirect_to @post, notice: 'Post was successfully created.' }
+        format.json { render :show, status: :created, location: @post }
+      else
+        format.html { render :new }
+        format.json { render json: @post.errors, status: :unprocessable_entity }
+      end
+    end
+  end
+
+  def update
+    respond_to do |format|
+      if @post.update(post_params)
+        format.html { redirect_to @post, notice: 'Post was successfully updated.' }
+        format.json { render :show, status: :ok, location: @post }
+      else
+        format.html { render :edit }
+        format.json { render json: @post.errors, status: :unprocessable_entity }
+      end
+    end
+  end
+
+  def destroy
+    @post.destroy
+    respond_to do |format|
+      format.html { redirect_to posts_url, notice: 'Post was successfully destroyed.' }
+      format.json { head :no_content }
+    end
+  end
+
+  private
+
+    def set_post
+      @post = Post.find(params[:id])
+    end
+
+    def post_params
+      params.require(:post).permit(:title, :body, :user_id, :feature_image)
+    end
+end

app/helpers/posts_helper.rb

@@ -0,0 +1,2 @@
+module PostsHelper
+end

app/javascript/controllers/dropzone_controller.js

@@ -0,0 +1,155 @@
+import Dropzone from "dropzone";
+import { Controller } from "stimulus";
+import { DirectUpload } from "@rails/activestorage";
+import {
+  getMetaValue,
+  toArray,
+  findElement,
+  removeElement,
+  insertAfter
+} from "helpers";
+
+export default class extends Controller {
+  static targets = ["input"];
+
+  connect() {
+    this.dropZone = createDropZone(this);
+    this.hideFileInput();
+    this.bindEvents();
+    Dropzone.autoDiscover = false;
+  }
+
+  // Private
+  hideFileInput() {
+    this.inputTarget.disabled = true;
+    this.inputTarget.style.display = "none";
+  }
+
+  bindEvents() {
+    this.dropZone.on("addedfile", file => {
+      setTimeout(() => {
+        file.accepted && createDirectUploadController(this, file).start();
+      }, 500);
+    });
+
+    this.dropZone.on("removedfile", file => {
+      file.controller && removeElement(file.controller.hiddenInput);
+    });
+
+    this.dropZone.on("canceled", file => {
+      file.controller && file.controller.xhr.abort();
+    });
+  }
+
+  get headers() {
+    return { "X-CSRF-Token": getMetaValue("csrf-token") };
+  }
+
+  get url() {
+    return this.inputTarget.getAttribute("data-direct-upload-url");
+  }
+
+  get maxFiles() {
+    return this.data.get("maxFiles") || 1;
+  }
+
+  get maxFileSize() {
+    return this.data.get("maxFileSize") || 256;
+  }
+
+  get acceptedFiles() {
+    return this.data.get("acceptedFiles");
+  }
+
+  get addRemoveLinks() {
+    return this.data.get("addRemoveLinks") || true;
+  }
+}
+
+class DirectUploadController {
+  constructor(source, file) {
+    this.directUpload = createDirectUpload(file, source.url, this);
+    this.source = source;
+    this.file = file;
+  }
+
+  start() {
+    this.file.controller = this;
+    this.hiddenInput = this.createHiddenInput();
+    this.directUpload.create((error, attributes) => {
+      if (error) {
+        removeElement(this.hiddenInput);
+        this.emitDropzoneError(error);
+      } else {
+        this.hiddenInput.value = attributes.signed_id;
+        this.emitDropzoneSuccess();
+      }
+    });
+  }
+
+  createHiddenInput() {
+    const input = document.createElement("input");
+    input.type = "hidden";
+    input.name = this.source.inputTarget.name;
+    insertAfter(input, this.source.inputTarget);
+    return input;
+  }
+
+  directUploadWillStoreFileWithXHR(xhr) {
+    this.bindProgressEvent(xhr);
+    this.emitDropzoneUploading();
+  }
+
+  bindProgressEvent(xhr) {
+    this.xhr = xhr;
+    this.xhr.upload.addEventListener("progress", event =>
+      this.uploadRequestDidProgress(event)
+    );
+  }
+
+  uploadRequestDidProgress(event) {
+    const element = this.source.element;
+    const progress = (event.loaded / event.total) * 100;
+    findElement(
+      this.file.previewTemplate,
+      ".dz-upload"
+    ).style.width = `${progress}%`;
+  }
+
+  emitDropzoneUploading() {
+    this.file.status = Dropzone.UPLOADING;
+    this.source.dropZone.emit("processing", this.file);
+  }
+
+  emitDropzoneError(error) {
+    this.file.status = Dropzone.ERROR;
+    this.source.dropZone.emit("error", this.file, error);
+    this.source.dropZone.emit("complete", this.file);
+  }
+
+  emitDropzoneSuccess() {
+    this.file.status = Dropzone.SUCCESS;
+    this.source.dropZone.emit("success", this.file);
+    this.source.dropZone.emit("complete", this.file);
+  }
+}
+
+function createDirectUploadController(source, file) {
+  return new DirectUploadController(source, file);
+}
+
+function createDirectUpload(file, url, controller) {
+  return new DirectUpload(file, url, controller);
+}
+
+function createDropZone(controller) {
+  return new Dropzone(controller.element, {
+    url: controller.url,
+    headers: controller.headers,
+    maxFiles: controller.maxFiles,
+    maxFilesize: controller.maxFileSize,
+    acceptedFiles: controller.acceptedFiles,
+    addRemoveLinks: controller.addRemoveLinks,
+    autoQueue: false
+  });
+}

app/javascript/controllers/hello_controller.js

@@ -1,9 +1,9 @@
-// Load all the controllers within this directory and all subdirectories. 
+// Load all the controllers within this directory and all subdirectories.
 // Controller files must be named *_controller.js.
 
-import { Application } from "stimulus"
-import { definitionsFromContext } from "stimulus/webpack-helpers"
+import { Application } from "stimulus";
+import { definitionsFromContext } from "stimulus/webpack-helpers";
 
-const application = Application.start()
-const context = require.context("controllers", true, /_controller\.js$/)
-application.load(definitionsFromContext(context))
+const application = Application.start();
+const context = require.context("controllers", true, /_controller\.js$/);
+application.load(definitionsFromContext(context));

app/javascript/controllers/index.js

@@ -0,0 +1,34 @@
+export function getMetaValue(name) {
+  const element = findElement(document.head, `meta[name="${name}"]`);
+  if (element) {
+    return element.getAttribute("content");
+  }
+}
+
+export function findElement(root, selector) {
+  if (typeof root == "string") {
+    selector = root;
+    root = document;
+  }
+  return root.querySelector(selector);
+}
+
+export function toArray(value) {
+  if (Array.isArray(value)) {
+    return value;
+  } else if (Array.from) {
+    return Array.from(value);
+  } else {
+    return [].slice.call(value);
+  }
+}
+
+export function removeElement(el) {
+  if (el && el.parentNode) {
+    el.parentNode.removeChild(el);
+  }
+}
+
+export function insertAfter(el, referenceNode) {
+  return referenceNode.parentNode.insertBefore(el, referenceNode.nextSibling);
+}

app/javascript/helpers/index.js

@@ -1,4 +1,6 @@
-/* Forms */
+@import "dropzone/dist/min/dropzone.min.css";
+@import "dropzone/dist/min/basic.min.css";
+
 .input {
   @apply appearance-none block w-full bg-gray-100 text-gray-700 border border-gray-300 rounded py-3 px-4 leading-tight;
 }
@@ -14,9 +16,21 @@
 .select {
   @apply appearance-none py-3 px-4 pr-8 block w-full bg-gray-100 border border-gray-300 text-gray-700
    rounded leading-tight;
-   -webkit-appearance: none;
+  -webkit-appearance: none;
 }
 
 .select:focus {
   @apply outline-none bg-white border-gray-400;
 }
+
+.dropzone {
+  @apply border-2 rounded-lg border-gray-400 border-dashed;
+
+  &.dz-drag-hover {
+    @apply border-2 rounded-lg border-gray-200 border-dashed;
+
+    .dz-message {
+      opacity: 0.9;
+    }
+  }
+}

app/javascript/stylesheets/components/_forms.scss

@@ -0,0 +1,4 @@
+class Post < ApplicationRecord
+  belongs_to :user
+  has_one_attached :feature_image
+end

app/models/post.rb

@@ -0,0 +1,38 @@
+<%= form_with(model: post, local: true, multipart: true) do |form| %>
+  <% if post.errors.any? %>
+    <div id="error_explanation">
+      <h2><%= pluralize(post.errors.count, "error") %> prohibited this post from being saved:</h2>
+
+      <ul>
+        <% post.errors.full_messages.each do |message| %>
+          <li><%= message %></li>
+        <% end %>
+      </ul>
+    </div>
+  <% end %>
+
+  <div class="mb-6">
+    <%= form.label :title, class: "label" %>
+    <%= form.text_field :title, class: "input" %>
+  </div>
+
+  <div class="mb-6">
+    <%= form.label :body, class: "label" %>
+    <%= form.text_area :body, class: "input" %>
+  </div>
+
+  <div class="mb-6">
+    <%= form.label :feature_image, class: "label" %>
+    <div class="dropzone dropzone-default dz-clickable" data-controller="dropzone" data-dropzone-max-file-size="2" data-dropzone-max-files="1">
+    <%= form.file_field :feature_image, direct_upload: true, data: { target: 'dropzone.input' } %>
+    <div class="dropzone-msg dz-message needsclick text-gray-600">
+      <h3 class="dropzone-msg-title">Drag here to upload or click here to browse</h3>
+      <span class="dropzone-msg-desc text-sm">2 MB file size maximum. Allowed file types png, jpg.</span>
+      </div>
+    </div>
+  </div>
+
+  <div class="mb-6">
+    <%= form.submit  class: "btn-default btn" %>
+  </div>
+<% end %>

app/views/posts/_form.html.erb

@@ -0,0 +1,2 @@
+json.extract! post, :id, :title, :body, :user_id, :created_at, :updated_at
+json.url post_url(post, format: :json)

app/views/posts/_post.json.jbuilder

@@ -0,0 +1,5 @@
+<div class="max-w-2xl m-auto">
+  <h1 class="text-3xl font-bold text-black mb-6">Edit Post</h1>
+
+  <%= render 'form', post: @post %>
+</div>