From 9cf30e74e6c43e1d450c1dd94ce43751e7834f7c Mon Sep 17 00:00:00 2001
From: John Cowen <johncowen@users.noreply.github.com>
Date: Mon, 30 Nov 2020 15:05:16 +0000
Subject: [PATCH] ui: Nestable DataSources (plus glimmer upgrade) (#9275)

---
 .../app/components/data-source/README.mdx     |  85 ++++++-
 .../app/components/data-source/index.hbs      |  26 +-
 .../app/components/data-source/index.js       | 226 +++++++++++-------
 .../app/services/data-source/service.js       |  19 +-
 .../components/data-source-test.js            |  41 ++--
 5 files changed, 275 insertions(+), 122 deletions(-)

diff --git a/ui/packages/consul-ui/app/components/data-source/README.mdx b/ui/packages/consul-ui/app/components/data-source/README.mdx
index 0c19966279..da886c759f 100644
--- a/ui/packages/consul-ui/app/components/data-source/README.mdx
+++ b/ui/packages/consul-ui/app/components/data-source/README.mdx
@@ -2,11 +2,14 @@
 
 ```handlebars
 <DataSource
-  @src="/dc/nspace/services"
+  @src="/nspace/dc/services"
   @loading="eager"
+  @disabled={{false}}
   @onchange={{action (mut items) value="data"}}
   @onerror={{action (mut error) value="error"}}
-/>
+as |source|>
+  <source.Source @src="" />
+</DataSource>
 ```
 
 ### Arguments
@@ -15,6 +18,7 @@
 | --- | --- | --- | --- |
 | `src` | `String` | | The source to subscribe to updates to, this should map to a string based URI |
 | `loading` | `String` | eager | Allows the browser to defer loading offscreen DataSources (`eager\|lazy`). Setting to `lazy` only loads the data when the DataSource is visible in the DOM (inc. `display: none\|block;`) |
+| `disabled` | `Boolean` | true | When disabled the DataSource is closed |
 | `open` | `Boolean` | false | Force the DataSource to open, used to force non-blocking data to refresh (has no effect for blocking data) |
 | `onchange` | `Function` |  | The action to fire when the data changes. Emits an Event-like object with a `data` property containing the data. |
 | `onerror` | `Function` |  | The action to fire when an error occurs. Emits ErrorEvent object with an `error` property containing the Error. |
@@ -30,23 +34,31 @@ Behind the scenes in the Consul UI we map URIs back to our `ember-data` backed `
 `DataSource` is not just restricted to HTTP API data, and can be configured to listen for data changes using a variety of methods and sources. For example we have also configured `DataSource` to listen to `LocalStorage` changes using the `settings://` pseudo-protocol in the URI (See examples below).
 
 
-### Example
+### Examples
 
-Straightforward usage can use `mut` to easily update data within a template
+Straightforward usage can use `mut` to easily update data within a template using an event handler approach.
 
 ```handlebars
   {{! listen for HTTP API changes}}
-  <DataSource @src="/dc/nspace/services"
+  <DataSource
+    @src="/nspace/dc/services"
     @onchange={{action (mut items) value="data"}}
     @onerror={{action (mut error) value="error"}}
   />
+  {{#if error}}
+    Something went wrong!
+  {{/if}}
+  {{#if (not items)}}
+    Loading...
+  {{/if}}
   {{! the value of items will change whenever the data changes}}
   {{#each items as |item|}}
     {{item.Name}} {{! < Prints the item name }}
   {{/each}}
 
   {{! listen for Settings (local storage) changes}}
-  <DataSource @src="settings://consul:token"
+  <DataSource
+    @src="settings://consul:token"
     @onchange={{action (mut token) value="data"}}
     @onerror={{action (mut error) value="error"}}
   />
@@ -54,6 +66,67 @@ Straightforward usage can use `mut` to easily update data within a template
   {{token.AccessorID}} {{! < Prints the token AccessorID }}
 ```
 
+A property approach to easily update data within a template
+
+```handlebars
+  {{! listen for HTTP API changes}}
+  <DataSource
+    @src="/nspace/dc/services"
+  as |source|>
+    {{#if source.error}}
+      Something went wrong!
+    {{/if}}
+    {{#if (not source.data)}}
+      Loading...
+    {{/if}}
+    {{! the value of items will change whenever the data changes}}
+    {{#each source.data as |item|}}
+      {{item.Name}} {{! < Prints the item name }}
+    {{/each}}
+  </DataSource>
+```
+
+Both approaches can be used in tandem.
+
+DataSources can also be recursively nested for loading in series as opposed to in parallel. Nested DataSources will not start loading until the immediate parent has loaded (ie. it has data) as they are not placed into the DOM until this has happened. However, if a DataSource has started loading, and the immediate parent errors, the nested DataSource will stop receiving updates yet it and its properties will remain accessible within the DOM.
+
+```handlebars
+
+  {{! straightforwards error/loading states}}
+  {{#if error}}
+    Something went wrong!
+  {{else if (not loaded)}}
+    Loading...
+  {{/if}}
+
+  {{! listen for HTTP API changes}}
+  <DataSource
+    @src="/nspace/dc/services"
+    @onerror={{action (mut error) value="error"}}
+  as |source|>
+
+    <source.Source
+      @src="/nspace/dc/service/{{source.data.firstObject.Name}}"
+      @onerror={{action (mut error) value="error"}}
+    as |source|>
+
+      {{source.data.Service.Service.Name}} <== Detailed information for the first service
+
+      <source.Source
+        @src="/nspace/dc/proxy/for-service/{{source.data.Service.ID}}"
+        @onerror={{action (mut error) value="error"}}
+        @onchange={{action (mut loaded) true}}
+      as |source|>
+
+        {{source.data.DestinationName}}
+
+      </source.Source>
+
+    </source.Source>
+
+  </DataSource>
+```
+
 ### See
 
 - [Component Source Code](./index.js)
diff --git a/ui/packages/consul-ui/app/components/data-source/index.hbs b/ui/packages/consul-ui/app/components/data-source/index.hbs
index 3e9f7250ec..de3b6c8de9 100644
--- a/ui/packages/consul-ui/app/components/data-source/index.hbs
+++ b/ui/packages/consul-ui/app/components/data-source/index.hbs
@@ -1,4 +1,24 @@
-{{#if (eq loading "lazy")}}
-{{! in order to use intersection observer we need a DOM element on the page}}
-  <data id={{guid}} aria-hidden="true" style="width: 0;height: 0;font-size: 0;padding: 0;margin: 0;" />
+{{#if (not this.disabled)}}
+  {{#if (eq this.loading "lazy")}}
+    {{! in order to use intersection observer we need a DOM element on the page}}
+    <data
+      {{did-insert this.connect}}
+      aria-hidden="true"
+      style="width: 0;height: 0;font-size: 0;padding: 0;margin: 0;"
+    />
+  {{else}}
+    {{did-insert this.connect}}
+  {{/if}}
+  {{did-update this.attributeChanged 'src' @src}}
+  {{did-update this.attributeChanged 'loading' @loading}}
+  {{will-destroy this.disconnect}}
 {{/if}}
+{{did-update this.attributeChanged 'disabled' @disabled}}
+{{yield (hash
+  data=this.data
+  error=this.error
+  Source=(if this.data
+    (component 'data-source' disabled=(not (eq this.error undefined)))
+    ''
+  )
+)}}
diff --git a/ui/packages/consul-ui/app/components/data-source/index.js b/ui/packages/consul-ui/app/components/data-source/index.js
index e307d81e97..466efce130 100644
--- a/ui/packages/consul-ui/app/components/data-source/index.js
+++ b/ui/packages/consul-ui/app/components/data-source/index.js
@@ -1,6 +1,7 @@
-import Component from '@ember/component';
+import Component from '@glimmer/component';
 import { inject as service } from '@ember/service';
-import { set, get } from '@ember/object';
+import { tracked } from '@glimmer/tracking';
+import { action, get } from '@ember/object';
 import { schedule } from '@ember/runloop';
 
 /**
@@ -22,119 +23,160 @@ const replace = function(
   if (prev !== value) {
     destroy(prev, value);
   }
-  return set(obj, prop, value);
+  return (obj[prop] = value);
 };
 
-export default Component.extend({
-  tagName: '',
+const noop = () => {};
+const optional = op => (typeof op === 'function' ? op : noop);
 
-  data: service('data-source/service'),
-  dom: service('dom'),
-  logger: service('logger'),
+// possible values for @loading=""
+const LOADING = ['eager', 'lazy'];
 
-  onchange: function(e) {},
-  onerror: function(e) {},
+export default class DataSource extends Component {
+  @service('data-source/service') dataSource;
+  @service('dom') dom;
+  @service('logger') logger;
 
-  loading: 'eager',
+  @tracked isIntersecting = false;
+  @tracked data;
+  @tracked error;
 
-  isIntersecting: false,
-
-  init: function() {
-    this._super(...arguments);
+  constructor(owner, args) {
+    super(...arguments);
     this._listeners = this.dom.listeners();
     this._lazyListeners = this.dom.listeners();
-    this.guid = this.dom.guid(this);
-  },
-  willDestroyElement: function() {
-    this.actions.close.apply(this);
-    this._listeners.remove();
-    this._lazyListeners.remove();
-    this._super(...arguments);
-  },
+  }
 
-  didInsertElement: function() {
-    this._super(...arguments);
-    if (this.loading === 'lazy') {
+  get loading() {
+    return LOADING.includes(this.args.loading) ? this.args.loading : LOADING[0];
+  }
+
+  get disabled() {
+    return typeof this.args.disabled !== 'undefined' ? this.args.disabled : false;
+  }
+
+  onchange(e) {
+    this.error = undefined;
+    this.data = e.data;
+    optional(this.args.onchange)(e);
+  }
+
+  onerror(e) {
+    this.error = e.error || e;
+    optional(this.args.onerror)(e);
+  }
+
+  @action
+  connect($el) {
+    // $el is only a DOM node when loading = lazy
+    // otherwise its an array from the did-insert-helper
+    if (!Array.isArray($el)) {
       this._lazyListeners.add(
-        this.dom.isInViewport(this.dom.element(`#${this.guid}`), inViewport => {
-          set(this, 'isIntersecting', inViewport);
+        this.dom.isInViewport($el, inViewport => {
+          this.isIntersecting = inViewport;
           if (!this.isIntersecting) {
-            this.actions.close.bind(this)();
+            this.close();
           } else {
-            this.actions.open.bind(this)();
+            this.open();
           }
         })
       );
-    }
-  },
-  didReceiveAttrs: function() {
-    this._super(...arguments);
-    if (this.loading === 'eager') {
+    } else {
       this._lazyListeners.remove();
+      this.open();
     }
-    if (this.loading === 'eager' || this.isIntersecting) {
-      this.actions.open.apply(this, []);
-    }
-  },
-  actions: {
-    // keep this argumentless
-    open: function() {
-      // get a new source and replace the old one, cleaning up as we go
-      const source = replace(
-        this,
-        'source',
-        this.data.open(this.src, this, this.open),
-        (prev, source) => {
-          // Makes sure any previous source (if different) is ALWAYS closed
-          this.data.close(prev, this);
+  }
+
+  @action
+  disconnect() {
+    this.close();
+    this._listeners.remove();
+    this._lazyListeners.remove();
+  }
+
+  @action
+  attributeChanged([name, value]) {
+    switch (name) {
+      case 'src':
+        if (this.loading === 'eager' || this.isIntersecting) {
+          this.open();
         }
-      );
-      const error = err => {
+        break;
+    }
+  }
+
+  // keep this argumentless
+  @action
+  open() {
+    const src = this.args.src;
+    // get a new source and replace the old one, cleaning up as we go
+    const source = replace(
+      this,
+      'source',
+      this.dataSource.open(src, this, this.open),
+      (prev, source) => {
+        // Makes sure any previous source (if different) is ALWAYS closed
+        this.dataSource.close(prev, this);
+      }
+    );
+    const error = err => {
+      try {
+        const error = get(err, 'error.errors.firstObject') || {};
+        if (get(error, 'status') !== '429') {
+          this.onerror(err);
+        }
+        this.logger.execute(err);
+      } catch (err) {
+        this.logger.execute(err);
+      }
+    };
+    // set up the listeners (which auto cleanup on component destruction)
+    const remove = this._listeners.add(this.source, {
+      message: e => {
         try {
-          const error = get(err, 'error.errors.firstObject');
-          if (get(error || {}, 'status') !== '429') {
-            this.onerror(err);
-          }
-          this.logger.execute(err);
+          this.onchange(e);
         } catch (err) {
-          this.logger.execute(err);
+          error(err);
         }
-      };
-      // set up the listeners (which auto cleanup on component destruction)
-      const remove = this._listeners.add(this.source, {
-        message: e => {
+      },
+      error: e => {
+        error(e);
+      },
+    });
+    replace(this, '_remove', remove);
+    // dispatch the current data of the source if we have any
+    if (typeof source.getCurrentEvent === 'function') {
+      const currentEvent = source.getCurrentEvent();
+      if (currentEvent) {
+        let method;
+        if (typeof currentEvent.error !== 'undefined') {
+          method = 'onerror';
+          this.error = currentEvent.error;
+        } else {
+          this.error = undefined;
+          this.data = currentEvent.data;
+          method = 'onchange';
+        }
+
+        // avoid the re-render error
+        schedule('afterRender', () => {
           try {
-            this.onchange(e);
+            this[method](currentEvent);
           } catch (err) {
             error(err);
           }
-        },
-        error: e => {
-          error(e);
-        },
-      });
-      replace(this, '_remove', remove);
-      // dispatch the current data of the source if we have any
-      if (typeof source.getCurrentEvent === 'function') {
-        const currentEvent = source.getCurrentEvent();
-        if (currentEvent) {
-          schedule('afterRender', () => {
-            try {
-              this.onchange(currentEvent);
-            } catch (err) {
-              error(err);
-            }
-          });
-        }
+        });
       }
-    },
-    // keep this argumentless
-    close: function() {
-      if (typeof this.source !== 'undefined') {
-        this.data.close(this.source, this);
-        replace(this, '_remove', undefined);
-        set(this, 'source', undefined);
-      }
-    },
-  },
-});
+    }
+  }
+
+  // keep this argumentless
+  @action
+  close() {
+    if (typeof this.source !== 'undefined') {
+      this.dataSource.close(this.source, this);
+      replace(this, '_remove', undefined);
+      this.source = undefined;
+    }
+  }
+}
diff --git a/ui/packages/consul-ui/app/services/data-source/service.js b/ui/packages/consul-ui/app/services/data-source/service.js
index 24b7d04625..7e8b2a95ee 100644
--- a/ui/packages/consul-ui/app/services/data-source/service.js
+++ b/ui/packages/consul-ui/app/services/data-source/service.js
@@ -1,5 +1,6 @@
 import Service, { inject as service } from '@ember/service';
 import { proxy } from 'consul-ui/utils/dom/event-source';
+import { schedule } from '@ember/runloop';
 
 import MultiMap from 'mnemonist/multi-map';
 
@@ -37,14 +38,18 @@ export default class DataSourceService extends Service {
   }
 
   willDestroy() {
-    this._listeners.remove();
-    sources.forEach(function(item) {
-      item.close();
+    // the will-destroy helper will fire AFTER services have had willDestroy
+    // called on them, schedule any destroying to fire after the final render
+    schedule('afterRender', () => {
+      this._listeners.remove();
+      sources.forEach(function(item) {
+        item.close();
+      });
+      cache = null;
+      sources = null;
+      usage.clear();
+      usage = null;
     });
-    cache = null;
-    sources = null;
-    usage.clear();
-    usage = null;
   }
 
   source(cb, attrs) {
diff --git a/ui/packages/consul-ui/tests/integration/components/data-source-test.js b/ui/packages/consul-ui/tests/integration/components/data-source-test.js
index 530dbb0a3f..10702240a5 100644
--- a/ui/packages/consul-ui/tests/integration/components/data-source-test.js
+++ b/ui/packages/consul-ui/tests/integration/components/data-source-test.js
@@ -4,8 +4,9 @@ import { clearRender, render, waitUntil } from '@ember/test-helpers';
 import hbs from 'htmlbars-inline-precompile';
 
 import test from 'ember-sinon-qunit/test-support/test';
-import Service from '@ember/service';
+import Service, { inject as service } from '@ember/service';
 
+import DataSourceComponent from 'consul-ui/components/data-source/index';
 import { BlockingEventSource as RealEventSource } from 'consul-ui/utils/dom/event-source';
 
 const createFakeBlockingEventSource = function() {
@@ -43,8 +44,9 @@ module('Integration | Component | data-source', function(hooks) {
     const addEventListener = this.stub();
     const removeEventListener = this.stub();
     let count = 0;
-    const fakeService = Service.extend({
-      open: function(uri, obj) {
+    const fakeService = class extends Service {
+      close = close;
+      open(uri, obj) {
         open(uri);
         const source = new BlockingEventSource();
         source.getCurrentEvent = function() {
@@ -53,17 +55,23 @@ module('Integration | Component | data-source', function(hooks) {
         source.addEventListener = addEventListener;
         source.removeEventListener = removeEventListener;
         return source;
-      },
-      close: close,
-    });
+      }
+    };
     this.owner.register('service:data-source/fake-service', fakeService);
-    this.owner.inject('component:data-source', 'data', 'service:data-source/fake-service');
+    this.owner.register(
+      'component:data-source',
+      class extends DataSourceComponent {
+        @service('data-source/fake-service') dataSource;
+      }
+    );
     this.actions.change = data => {
       count++;
       switch (count) {
         case 1:
           assert.equal(data, 'a', 'change was called first with "a"');
-          setTimeout(() => this.set('src', 'b'), 0);
+          setTimeout(() => {
+            this.set('src', 'b');
+          }, 0);
           break;
         case 2:
           assert.equal(data, 'b', 'change was called second with "b"');
@@ -92,17 +100,22 @@ module('Integration | Component | data-source', function(hooks) {
     const source = new RealEventSource();
     const error = this.stub();
     const close = this.stub();
-    const fakeService = Service.extend({
-      open: function(uri, obj) {
+    const fakeService = class extends Service {
+      close = close;
+      open(uri, obj) {
         source.getCurrentEvent = function() {
           return {};
         };
         return source;
-      },
-      close: close,
-    });
+      }
+    };
     this.owner.register('service:data-source/fake-service', fakeService);
-    this.owner.inject('component:data-source', 'data', 'service:data-source/fake-service');
+    this.owner.register(
+      'component:data-source',
+      class extends DataSourceComponent {
+        @service('data-source/fake-service') dataSource;
+      }
+    );
     this.actions.change = data => {
       source.dispatchEvent({ type: 'error', error: {} });
     };