Enable metrics dashboards to be rearranged

- Add feature to have panels drag and drop using vuedraggable
- Enable draggable panels have a different appearance
- Add property to enable feature, disabled by default
- Add vuedraggable as a dependency

app/assets/javascripts/monitoring/components/dashboard.vue

 <script>
+import _ from 'underscore';
+import { mapActions, mapState } from 'vuex';
+import VueDraggable from 'vuedraggable';
 import {
   GlButton,
   GlDropdown,
@@ -8,8 +11,6 @@ import {
   GlModalDirective,
   GlTooltipDirective,
 } from '@gitlab/ui';
-import _ from 'underscore';
-import { mapActions, mapState } from 'vuex';
 import { __, s__ } from '~/locale';
 import Icon from '~/vue_shared/components/icon.vue';
 import { getParameterValues, mergeUrlParams } from '~/lib/utils/url_utility';
@@ -26,6 +27,7 @@ let sidebarMutationObserver;
 
 export default {
   components: {
+    VueDraggable,
     MonitorTimeSeriesChart,
     MonitorSingleStatChart,
     PanelType,
@@ -151,6 +153,11 @@ export default {
       required: false,
       default: false,
     },
+    rearrangePanelsAvailable: {
+      type: Boolean,
+      required: false,
+      default: false,
+    },
   },
   data() {
     return {
@@ -160,6 +167,7 @@ export default {
       selectedTimeWindowKey: '',
       formIsValid: null,
       timeWindows: {},
+      isRearrangingPanels: false,
     };
   },
   computed: {
@@ -183,6 +191,9 @@ export default {
     selectedDashboardText() {
       return this.currentDashboard || this.firstDashboard.display_name;
     },
+    showRearrangePanelsBtn() {
+      return !this.showEmptyState && this.rearrangePanelsAvailable;
+    },
     addingMetricsAvailable() {
       return IS_EE && this.canAddMetrics && !this.showEmptyState;
     },
@@ -274,6 +285,11 @@ export default {
       this.$toast.show(__('Link copied'));
     },
     // TODO: END
+    removeGraph(metrics, graphIndex) {
+      // At present graphs will not be removed, they should removed using the vuex store
+      // See https://gitlab.com/gitlab-org/gitlab/issues/27835
+      metrics.splice(graphIndex, 1);
+    },
     generateLink(group, title, yLabel) {
       const dashboard = this.currentDashboard || this.firstDashboard.path;
       const params = _.pick({ dashboard, group, title, y_label: yLabel }, value => value != null);
@@ -287,6 +303,9 @@ export default {
         this.elWidth = this.$el.clientWidth;
       }, sidebarAnimationDuration);
     },
+    toggleRearrangingPanels() {
+      this.isRearrangingPanels = !this.isRearrangingPanels;
+    },
     setFormValidity(isValid) {
       this.formIsValid = isValid;
     },
@@ -389,15 +408,27 @@ export default {
         </template>
 
         <gl-form-group
-          v-if="addingMetricsAvailable || externalDashboardUrl.length"
+          v-if="addingMetricsAvailable || showRearrangePanelsBtn || externalDashboardUrl.length"
           label-for="prometheus-graphs-dropdown-buttons"
           class="dropdown-buttons col-lg d-lg-flex align-items-end"
         >
           <div id="prometheus-graphs-dropdown-buttons">
+            <gl-button
+              v-if="showRearrangePanelsBtn"
+              :pressed="isRearrangingPanels"
+              new-style
+              variant="default"
+              class="mr-2 mt-1 js-rearrange-button"
+              @click="toggleRearrangingPanels"
+            >
+              {{ __('Arrange charts') }}
+            </gl-button>
             <gl-button
               v-if="addingMetricsAvailable"
               v-gl-modal="$options.addMetric.modalId"
-              class="mr-2 mt-1 js-add-metric-button text-success border-success"
+              new-style
+              variant="outline-success"
+              class="mr-2 mt-1 js-add-metric-button"
             >
               {{ $options.addMetric.title }}
             </gl-button>
@@ -451,17 +482,42 @@ export default {
         :collapse-group="groupHasData(groupData)"
       >
         <template v-if="additionalPanelTypesEnabled">
-          <panel-type
+          <vue-draggable
+            :list="groupData.metrics"
+            group="metrics-dashboard"
+            :component-data="{ attrs: { class: 'row mx-0 w-100' } }"
+            :disabled="!isRearrangingPanels"
+          >
+            <div
               v-for="(graphData, graphIndex) in groupData.metrics"
               :key="`panel-type-${graphIndex}`"
-            class="col-12 col-lg-6 pb-3"
-            :clipboard-text="generateLink(groupData.group, graphData.title, graphData.y_label)"
+              class="col-12 col-lg-6 px-2 mb-2 draggable"
+              :class="{ 'draggable-enabled': isRearrangingPanels }"
+            >
+              <div class="position-relative draggable-panel js-draggable-panel">
+                <div
+                  v-if="isRearrangingPanels"
+                  class="draggable-remove js-draggable-remove p-2 w-100 position-absolute d-flex justify-content-end"
+                  @click="removeGraph(groupData.metrics, graphIndex)"
+                >
+                  <a class="mx-2 p-2 draggable-remove-link" :aria-label="__('Remove')"
+                    ><icon name="close"
+                  /></a>
+                </div>
+
+                <panel-type
+                  :clipboard-text="
+                    generateLink(groupData.group, graphData.title, graphData.y_label)
+                  "
                   :graph-data="graphData"
                   :dashboard-width="elWidth"
                   :alerts-endpoint="alertsEndpoint"
                   :prometheus-alerts-available="prometheusAlertsAvailable"
                   :index="`${index}-${graphIndex}`"
                 />
+              </div>
+            </div>
+          </vue-draggable>
         </template>
         <template v-else>
           <monitor-time-series-chart

app/assets/javascripts/monitoring/components/graph_group.vue

@@ -52,7 +52,7 @@ export default {
     <div
       v-if="collapseGroup"
       v-show="collapseGroup && showGroup"
-      class="card-body prometheus-graph-group"
+      class="card-body prometheus-graph-group p-0"
     >
       <slot></slot>
     </div>

app/assets/stylesheets/pages/prometheus.scss

@@ -15,6 +15,37 @@
   }
 }
 
+.draggable {
+  &.draggable-enabled {
+    .draggable-panel {
+      border: $gray-200 1px solid;
+      border-radius: $border-radius-default;
+      margin: -1px;
+      cursor: grab;
+    }
+
+    .prometheus-graph {
+      // Make dragging easier by disabling use of chart
+      pointer-events: none;
+    }
+  }
+
+  &.sortable-chosen .draggable-panel {
+    background: $white-light;
+    box-shadow: 0 0 4px $gray-500;
+  }
+
+  .draggable-remove {
+    z-index: 1;
+
+    .draggable-remove-link {
+      cursor: pointer;
+      color: $gray-600;
+      background-color: $white-light;
+    }
+  }
+}
+
 .prometheus-panel {
   margin-top: 20px;
 }
@@ -22,11 +53,11 @@
 .prometheus-graph-group {
   display: flex;
   flex-wrap: wrap;
-  padding: $gl-padding / 2;
+  margin-top: $gl-padding-8;
 }
 
 .prometheus-graph {
-  padding: $gl-padding / 2;
+  padding: $gl-padding-8;
 }
 
 .prometheus-graph-embed {

changelogs/unreleased/27835-move-and-resize-panels-in-dashboard-save-to-branch.yml

+---
+title: Add property to enable metrics dashboards to be rearranged
+merge_request: 16605
+author:
+type: changed

locale/gitlab.pot

@@ -1889,6 +1889,9 @@ msgstr ""
 msgid "Are you sure? This will invalidate your registered applications and U2F devices."
 msgstr ""
 
+msgid "Arrange charts"
+msgstr ""
+
 msgid "Artifact ID"
 msgstr ""
 

spec/javascripts/monitoring/components/dashboard_spec.js

 import Vue from 'vue';
 import { shallowMount, createLocalVue } from '@vue/test-utils';
 import { GlToast } from '@gitlab/ui';
+import VueDraggable from 'vuedraggable';
 import MockAdapter from 'axios-mock-adapter';
 import Dashboard from '~/monitoring/components/dashboard.vue';
 import { timeWindows, timeWindowsKeyNames } from '~/monitoring/constants';
@@ -51,11 +52,6 @@ describe('Dashboard', () => {
       <div class="layout-page"></div>
     `);
 
-    window.gon = {
-      ...window.gon,
-      ee: false,
-    };
-
     store = createStore();
     mock = new MockAdapter(axios);
     DashboardComponent = Vue.extend(Dashboard);
@@ -378,7 +374,101 @@ describe('Dashboard', () => {
     });
   });
 
-  // https://gitlab.com/gitlab-org/gitlab-foss/issues/66922
+  describe('drag and drop function', () => {
+    let wrapper;
+    let expectedPanelCount; // also called metrics, naming to be improved: https://gitlab.com/gitlab-org/gitlab/issues/31565
+    const findDraggables = () => wrapper.findAll(VueDraggable);
+    const findEnabledDraggables = () => findDraggables().filter(f => !f.attributes('disabled'));
+    const findDraggablePanels = () => wrapper.findAll('.js-draggable-panel');
+    const findRearrangeButton = () => wrapper.find('.js-rearrange-button');
+
+    beforeEach(done => {
+      mock.onGet(mockApiEndpoint).reply(200, metricsGroupsAPIResponse);
+      expectedPanelCount = metricsGroupsAPIResponse.data.reduce(
+        (acc, d) => d.metrics.length + acc,
+        0,
+      );
+      store.dispatch('monitoringDashboard/setFeatureFlags', { additionalPanelTypesEnabled: true });
+
+      wrapper = shallowMount(DashboardComponent, {
+        localVue,
+        sync: false,
+        propsData: { ...propsData, hasMetrics: true },
+        store,
+      });
+
+      // not using $nextTicket becuase we must wait for the dashboard
+      // to be populated with the mock data results.
+      setTimeout(done);
+    });
+
+    it('wraps vuedraggable', () => {
+      expect(findDraggablePanels().exists()).toBe(true);
+      expect(findDraggablePanels().length).toEqual(expectedPanelCount);
+    });
+
+    it('is disabled by default', () => {
+      expect(findRearrangeButton().exists()).toBe(false);
+      expect(findEnabledDraggables().length).toBe(0);
+    });
+
+    describe('when rearrange is enabled', () => {
+      beforeEach(done => {
+        wrapper.setProps({ rearrangePanelsAvailable: true });
+        wrapper.vm.$nextTick(done);
+      });
+
+      it('displays rearrange button', () => {
+        expect(findRearrangeButton().exists()).toBe(true);
+      });
+
+      describe('when rearrange button is clicked', () => {
+        const findFirstDraggableRemoveButton = () =>
+          findDraggablePanels()
+            .at(0)
+            .find('.js-draggable-remove');
+
+        beforeEach(done => {
+          findRearrangeButton().vm.$emit('click');
+          wrapper.vm.$nextTick(done);
+        });
+
+        it('it enables draggables', () => {
+          expect(findRearrangeButton().attributes('pressed')).toBeTruthy();
+          expect(findEnabledDraggables()).toEqual(findDraggables());
+        });
+
+        it('shows a remove button, which removes a panel', done => {
+          expect(findFirstDraggableRemoveButton().isEmpty()).toBe(false);
+
+          expect(findDraggablePanels().length).toEqual(expectedPanelCount);
+          findFirstDraggableRemoveButton().trigger('click');
+
+          wrapper.vm.$nextTick(() => {
+            // At present graphs will not be removed in backend
+            // See https://gitlab.com/gitlab-org/gitlab/issues/27835
+            expect(findDraggablePanels().length).toEqual(expectedPanelCount - 1);
+            done();
+          });
+        });
+
+        it('it disables draggables when clicked again', done => {
+          findRearrangeButton().vm.$emit('click');
+          wrapper.vm.$nextTick(() => {
+            expect(findRearrangeButton().attributes('pressed')).toBeFalsy();
+            expect(findEnabledDraggables().length).toBe(0);
+            done();
+          });
+        });
+      });
+    });
+
+    afterEach(() => {
+      wrapper.destroy();
+    });
+  });
+
+  // https://gitlab.com/gitlab-org/gitlab-ce/issues/66922
   // eslint-disable-next-line jasmine/no-disabled-tests
   xdescribe('link to chart', () => {
     let wrapper;