Adds getters to filter results

* Moves search bar next to the button
* Adds minimal styling

app/assets/javascripts/error_tracking/components/error_tracking_list.vue

 <script>
-import { mapActions, mapState } from 'vuex';
-import { GlEmptyState, GlButton, GlLink, GlLoadingIcon, GlTable } from '@gitlab/ui';
+import { mapActions, mapState, mapGetters } from 'vuex';
+import {
+  GlEmptyState,
+  GlButton,
+  GlLink,
+  GlLoadingIcon,
+  GlTable,
+  GlSearchBoxByType,
+} from '@gitlab/ui';
 import Icon from '~/vue_shared/components/icon.vue';
 import TimeAgo from '~/vue_shared/components/time_ago_tooltip.vue';
 import { __ } from '~/locale';
@@ -20,6 +27,7 @@ export default {
     GlLink,
     GlLoadingIcon,
     GlTable,
+    GlSearchBoxByType,
     Icon,
     TimeAgo,
   },
@@ -48,8 +56,17 @@ export default {
       required: true,
     },
   },
+  data() {
+    return {
+      errorSearchQuery: '',
+    };
+  },
   computed: {
     ...mapState(['errors', 'externalUrl', 'loading']),
+    ...mapGetters(['filterErrorsByTitle']),
+    filteredErrors() {
+      return this.errorSearchQuery ? this.filterErrorsByTitle(this.errorSearchQuery) : this.errors;
+    },
   },
   created() {
     if (this.errorTrackingEnabled) {
@@ -71,10 +88,17 @@ export default {
         <gl-loading-icon :size="3" />
       </div>
       <div v-else>
-        <div class="d-flex justify-content-end">
+        <div class="d-flex flex-row justify-content-around bg-secondary border">
+          <gl-search-box-by-type
+            v-model="errorSearchQuery"
+            class="col-lg-10 m-3 p-0"
+            :placeholder="__('Search or filter results...')"
+            type="search"
+            autofocus
+          />
           <gl-button
             v-track-event="trackViewInSentryOptions(externalUrl)"
-            class="my-3 ml-auto"
+            class="m-3"
             variant="primary"
             :href="externalUrl"
             target="_blank"
@@ -84,7 +108,14 @@ export default {
           </gl-button>
         </div>
 
-        <gl-table :items="errors" :fields="$options.fields" :show-empty="true" fixed stacked="sm">
+        <gl-table
+          class="mt-3"
+          :items="filteredErrors"
+          :fields="$options.fields"
+          :show-empty="true"
+          fixed
+          stacked="sm"
+        >
           <template slot="HEAD_events" slot-scope="data">
             <div class="text-md-right">{{ data.label }}</div>
           </template>

app/assets/javascripts/error_tracking/store/getters.js

+export const filterErrorsByTitle = state => errorQuery =>
+  state.errors.filter(error => error.title.match(new RegExp(`${errorQuery}`, 'i')));
+
+export default () => {};

app/assets/javascripts/error_tracking/store/index.js

 import Vue from 'vue';
 import Vuex from 'vuex';
 import * as actions from './actions';
+import * as getters from './getters';
 import mutations from './mutations';
 
 Vue.use(Vuex);
@@ -14,6 +15,7 @@ export const createStore = () =>
     },
     actions,
     mutations,
+    getters,
   });
 
 export default createStore();

changelogs/unreleased/lm-search-list-of-sentry-errors.yml

+---
+title: Search list of Sentry errors by title in Gitlab
+merge_request: 18772
+author:
+type: added

doc/user/project/operations/error_tracking.md

@@ -41,5 +41,6 @@ NOTE: **Note:**
 You will need at least Reporter [permissions](../../permissions.md) to view the Error Tracking list.
 
 The Error Tracking list may be found at **Operations > Error Tracking** in your project's sidebar.
+Errors can be filtered by title.
 
 ![Error Tracking list](img/error_tracking_list.png)

spec/frontend/error_tracking/store/getters_spec.js

+import * as getters from '~/error_tracking/store/getters';
+
+describe('Error Tracking getters', () => {
+  let state;
+
+  const mockErrors = [
+    { title: 'ActiveModel::MissingAttributeError: missing attribute: encrypted_password' },
+    { title: 'Grape::Exceptions::MethodNotAllowed: Grape::Exceptions::MethodNotAllowed' },
+    { title: 'NoMethodError: undefined method `sanitize_http_headers=' },
+    { title: 'NoMethodError: undefined method `pry' },
+  ];
+
+  beforeEach(() => {
+    state = {
+      errors: mockErrors,
+    };
+  });
+
+  describe('search results', () => {
+    it('should return errors filtered by words in title matching the query', () => {
+      const filteredErrors = getters.filterErrorsByTitle(state)('NoMethod');
+
+      expect(filteredErrors).not.toContainEqual(mockErrors[0]);
+      expect(filteredErrors.length).toBe(2);
+    });
+
+    it('should not return results if there is no matching query', () => {
+      const filteredErrors = getters.filterErrorsByTitle(state)('GitLab');
+
+      expect(filteredErrors.length).toBe(0);
+    });
+  });
+});