1 files changed, 78 insertions, 0 deletions
diff --git a/app/assets/javascripts/issue_show/issue_title.js b/app/assets/javascripts/issue_show/issue_title.js
new file mode 100644
index 00000000000..1184c8956dc
--- /dev/null
+++ b/app/assets/javascripts/issue_show/issue_title.js
@@ -0,0 +1,78 @@
+import Visibility from 'visibilityjs';
+import Poll from './../lib/utils/poll';
+import Service from './services/index';
+
+export default {
+  props: {
+    initialTitle: { required: true, type: String },
+    endpoint: { required: true, type: String },
+  },
+  data() {
+    const resource = new Service(this.$http, this.endpoint);
+
+    const poll = new Poll({
+      resource,
+      method: 'getTitle',
+      successCallback: (res) => {
+        this.renderResponse(res);
+      },
+      errorCallback: (err) => {
+        if (process.env.NODE_ENV !== 'production') {
+          // eslint-disable-next-line no-console
+          console.error('ISSUE SHOW TITLE REALTIME ERROR', err);
+        } else {
+          throw new Error(err);
+        }
+      },
+    });
+
+    return {
+      poll,
+      timeoutId: null,
+      title: this.initialTitle,
+    };
+  },
+  methods: {
+    fetch() {
+      this.poll.makeRequest();
+
+      Visibility.change(() => {
+        if (!Visibility.hidden()) {
+          this.poll.restart();
+        } else {
+          this.poll.stop();
+        }
+      });
+    },
+    renderResponse(res) {
+      const body = JSON.parse(res.body);
+      this.triggerAnimation(body);
+    },
+    triggerAnimation(body) {
+      const { title } = body;
+
+      /**
+      * since opacity is changed, even if there is no diff for Vue to update
+      * we must check the title even on a 304 to ensure no visual change
+      */
+      if (this.title === title) return;
+
+      this.$el.style.opacity = 0;
+
+      this.timeoutId = setTimeout(() => {
+        this.title = title;
+
+        this.$el.style.transition = 'opacity 0.2s ease';
+        this.$el.style.opacity = 1;
+
+        clearTimeout(this.timeoutId);
+      }, 100);
+    },
+  },
+  created() {
+    this.fetch();
+  },
+  template: `
+    <h2 class='title' v-html='title'></h2>
+  `,
+};