Add Knative metrics to Prometheus

23 files changed, 629 insertions, 186 deletions

diff --git a/app/assets/javascripts/serverless/components/area.vue b/app/assets/javascripts/serverless/components/area.vue
new file mode 100644
index 00000000000..32c9d6eccb8
--- /dev/null
+++ b/app/assets/javascripts/serverless/components/area.vue
@@ -0,0 +1,146 @@
+<script>
+import { GlAreaChart } from '@gitlab/ui/dist/charts';
+import { debounceByAnimationFrame } from '~/lib/utils/common_utils';
+import dateFormat from 'dateformat';
+import { X_INTERVAL } from '../constants';
+import { validateGraphData } from '../utils';
+
+let debouncedResize;
+
+export default {
+  components: {
+    GlAreaChart,
+  },
+  inheritAttrs: false,
+  props: {
+    graphData: {
+      type: Object,
+      required: true,
+      validator: validateGraphData,
+    },
+    containerWidth: {
+      type: Number,
+      required: true,
+    },
+  },
+  data() {
+    return {
+      tooltipPopoverTitle: '',
+      tooltipPopoverContent: '',
+      width: this.containerWidth,
+    };
+  },
+  computed: {
+    chartData() {
+      return this.graphData.queries.reduce((accumulator, query) => {
+        accumulator[query.unit] = query.result.reduce((acc, res) => acc.concat(res.values), []);
+        return accumulator;
+      }, {});
+    },
+    extractTimeData() {
+      return this.chartData.requests.map(data => data.time);
+    },
+    generateSeries() {
+      return {
+        name: 'Invocations',
+        type: 'line',
+        data: this.chartData.requests.map(data => [data.time, data.value]),
+        symbolSize: 0,
+      };
+    },
+    getInterval() {
+      const { result } = this.graphData.queries[0];
+
+      if (result.length === 0) {
+        return 1;
+      }
+
+      const split = result[0].values.reduce(
+        (acc, pair) => (pair.value > acc ? pair.value : acc),
+        1,
+      );
+
+      return split < X_INTERVAL ? split : X_INTERVAL;
+    },
+    chartOptions() {
+      return {
+        xAxis: {
+          name: 'time',
+          type: 'time',
+          axisLabel: {
+            formatter: date => dateFormat(date, 'h:MM TT'),
+          },
+          data: this.extractTimeData,
+          nameTextStyle: {
+            padding: [18, 0, 0, 0],
+          },
+        },
+        yAxis: {
+          name: this.yAxisLabel,
+          nameTextStyle: {
+            padding: [0, 0, 36, 0],
+          },
+          splitNumber: this.getInterval,
+        },
+        legend: {
+          formatter: this.xAxisLabel,
+        },
+        series: this.generateSeries,
+      };
+    },
+    xAxisLabel() {
+      return this.graphData.queries.map(query => query.label).join(', ');
+    },
+    yAxisLabel() {
+      const [query] = this.graphData.queries;
+      return `${this.graphData.y_label} (${query.unit})`;
+    },
+  },
+  watch: {
+    containerWidth: 'onResize',
+  },
+  beforeDestroy() {
+    window.removeEventListener('resize', debouncedResize);
+  },
+  created() {
+    debouncedResize = debounceByAnimationFrame(this.onResize);
+    window.addEventListener('resize', debouncedResize);
+  },
+  methods: {
+    formatTooltipText(params) {
+      const [seriesData] = params.seriesData;
+      this.tooltipPopoverTitle = dateFormat(params.value, 'dd mmm yyyy, h:MMTT');
+      this.tooltipPopoverContent = `${this.yAxisLabel}: ${seriesData.value[1]}`;
+    },
+    onResize() {
+      const { width } = this.$refs.areaChart.$el.getBoundingClientRect();
+      this.width = width;
+    },
+  },
+};
+</script>
+
+<template>
+  <div class="prometheus-graph">
+    <div class="prometheus-graph-header">
+      <h5 ref="graphTitle" class="prometheus-graph-title">{{ graphData.title }}</h5>
+      <div ref="graphWidgets" class="prometheus-graph-widgets"><slot></slot></div>
+    </div>
+    <gl-area-chart
+      ref="areaChart"
+      v-bind="$attrs"
+      :data="[]"
+      :option="chartOptions"
+      :format-tooltip-text="formatTooltipText"
+      :width="width"
+      :include-legend-avg-max="false"
+    >
+      <template slot="tooltipTitle">
+        {{ tooltipPopoverTitle }}
+      </template>
+      <template slot="tooltipContent">
+        {{ tooltipPopoverContent }}
+      </template>
+    </gl-area-chart>
+  </div>
+</template>
diff --git a/app/assets/javascripts/serverless/components/function_details.vue b/app/assets/javascripts/serverless/components/function_details.vue
index 4f89ad69129..b8906cfca4e 100644
--- a/app/assets/javascripts/serverless/components/function_details.vue
+++ b/app/assets/javascripts/serverless/components/function_details.vue
@@ -1,39 +1,77 @@
 <script>
+import _ from 'underscore';
+import { mapState, mapActions, mapGetters } from 'vuex';
 import PodBox from './pod_box.vue';
 import Url from './url.vue';
+import AreaChart from './area.vue';
+import MissingPrometheus from './missing_prometheus.vue';
 
 export default {
   components: {
     PodBox,
     Url,
+    AreaChart,
+    MissingPrometheus,
   },
   props: {
     func: {
       type: Object,
       required: true,
     },
+    hasPrometheus: {
+      type: Boolean,
+      required: false,
+      default: false,
+    },
+    clustersPath: {
+      type: String,
+      required: true,
+    },
+    helpPath: {
+      type: String,
+      required: true,
+    },
+  },
+  data() {
+    return {
+      elWidth: 0,
+    };
   },
   computed: {
     name() {
       return this.func.name;
     },
     description() {
-      return this.func.description;
+      return _.isString(this.func.description) ? this.func.description : '';
     },
     funcUrl() {
       return this.func.url;
     },
     podCount() {
-      return this.func.podcount || 0;
+      return Number(this.func.podcount) || 0;
     },
+    ...mapState(['graphData', 'hasPrometheusData']),
+    ...mapGetters(['hasPrometheusMissingData']),
+  },
+  created() {
+    this.fetchMetrics({
+      metricsPath: this.func.metricsUrl,
+      hasPrometheus: this.hasPrometheus,
+    });
+  },
+  mounted() {
+    this.elWidth = this.$el.clientWidth;
+  },
+  methods: {
+    ...mapActions(['fetchMetrics']),
   },
 };
 </script>
 
 <template>
   <section id="serverless-function-details">
-    <h3>{{ name }}</h3>
-    <div class="append-bottom-default">
+    <h3 class="serverless-function-name">{{ name }}</h3>
+    <div class="append-bottom-default serverless-function-description">
       <div v-for="(line, index) in description.split('\n')" :key="index">{{ line }}</div>
     </div>
     <url :uri="funcUrl" />
@@ -52,5 +90,13 @@ export default {
       </p>
     </div>
     <div v-else><p>No pods loaded at this time.</p></div>
+
+    <area-chart v-if="hasPrometheusData" :graph-data="graphData" :container-width="elWidth" />
+    <missing-prometheus
+      v-if="!hasPrometheus || hasPrometheusMissingData"
+      :help-path="helpPath"
+      :clusters-path="clustersPath"
+      :missing-data="hasPrometheusMissingData"
+    />
   </section>
 </template>
diff --git a/app/assets/javascripts/serverless/components/function_row.vue b/app/assets/javascripts/serverless/components/function_row.vue
index 773d18781fd..4b3bb078eae 100644
--- a/app/assets/javascripts/serverless/components/function_row.vue
+++ b/app/assets/javascripts/serverless/components/function_row.vue
@@ -1,4 +1,5 @@
 <script>
+import _ from 'underscore';
 import Timeago from '~/vue_shared/components/time_ago_tooltip.vue';
 import Url from './url.vue';
 import { visitUrl } from '~/lib/utils/url_utility';
@@ -19,6 +20,10 @@ export default {
       return this.func.name;
     },
     description() {
+      if (!_.isString(this.func.description)) {
+        return '';
+      }
+
       const desc = this.func.description.split('\n');
       if (desc.length > 1) {
         return desc[1];
diff --git a/app/assets/javascripts/serverless/components/functions.vue b/app/assets/javascripts/serverless/components/functions.vue
index 4bde409f906..f9b4e789563 100644
--- a/app/assets/javascripts/serverless/components/functions.vue
+++ b/app/assets/javascripts/serverless/components/functions.vue
@@ -1,5 +1,6 @@
 <script>
-import { GlSkeletonLoading } from '@gitlab/ui';
+import { mapState, mapActions, mapGetters } from 'vuex';
+import { GlLoadingIcon } from '@gitlab/ui';
 import FunctionRow from './function_row.vue';
 import EnvironmentRow from './environment_row.vue';
 import EmptyState from './empty_state.vue';
@@ -9,14 +10,9 @@ export default {
     EnvironmentRow,
     FunctionRow,
     EmptyState,
-    GlSkeletonLoading,
+    GlLoadingIcon,
   },
   props: {
-    functions: {
-      type: Object,
-      required: true,
-      default: () => ({}),
-    },
     installed: {
       type: Boolean,
       required: true,
@@ -29,17 +25,23 @@ export default {
       type: String,
       required: true,
     },
-    loadingData: {
-      type: Boolean,
-      required: false,
-      default: true,
-    },
-    hasFunctionData: {
-      type: Boolean,
-      required: false,
-      default: true,
+    statusPath: {
+      type: String,
+      required: true,
     },
   },
+  computed: {
+    ...mapState(['isLoading', 'hasFunctionData']),
+    ...mapGetters(['getFunctions']),
+  },
+  created() {
+    this.fetchFunctions({
+      functionsPath: this.statusPath,
+    });
+  },
+  methods: {
+    ...mapActions(['fetchFunctions']),
+  },
 };
 </script>
 
@@ -47,14 +49,16 @@ export default {
   <section id="serverless-functions">
     <div v-if="installed">
       <div v-if="hasFunctionData">
-        <template v-if="loadingData">
-          <div v-for="j in 3" :key="j" class="gl-responsive-table-row"><gl-skeleton-loading /></div>
-        </template>
+        <gl-loading-icon
+          v-if="isLoading"
+          :size="2"
+          class="prepend-top-default append-bottom-default"
+        />
         <template v-else>
           <div class="groups-list-tree-container">
             <ul class="content-list group-list-tree">
               <environment-row
-                v-for="(env, index) in functions"
+                v-for="(env, index) in getFunctions"
                 :key="index"
                 :env="env"
                 :env-name="index"
diff --git a/app/assets/javascripts/serverless/components/missing_prometheus.vue b/app/assets/javascripts/serverless/components/missing_prometheus.vue
new file mode 100644
index 00000000000..6c19434f202
--- /dev/null
+++ b/app/assets/javascripts/serverless/components/missing_prometheus.vue
@@ -0,0 +1,63 @@
+<script>
+import { GlButton, GlLink } from '@gitlab/ui';
+import { s__ } from '../../locale';
+
+export default {
+  components: {
+    GlButton,
+    GlLink,
+  },
+  props: {
+    clustersPath: {
+      type: String,
+      required: true,
+    },
+    helpPath: {
+      type: String,
+      required: true,
+    },
+    missingData: {
+      type: Boolean,
+      required: true,
+    },
+  },
+  computed: {
+    missingStateClass() {
+      return this.missingData ? 'missing-prometheus-state' : 'empty-prometheus-state';
+    },
+    prometheusHelpPath() {
+      return `${this.helpPath}#prometheus-support`;
+    },
+    description() {
+      return this.missingData
+        ? s__(`ServerlessDetails|Invocation metrics loading or not available at this time.`)
+        : s__(
+            `ServerlessDetails|Function invocation metrics require Prometheus to be installed first.`,
+          );
+    },
+  },
+};
+</script>
+
+<template>
+  <div class="row" :class="missingStateClass">
+    <div class="col-12">
+      <div class="text-content">
+        <h4 class="state-title text-left">{{ s__(`ServerlessDetails|Invocations`) }}</h4>
+        <p class="state-description">
+          {{ description }}
+          <gl-link :href="prometheusHelpPath">{{
+            s__(`ServerlessDetails|More information`)
+          }}</gl-link
+          >.
+        </p>
+
+        <div v-if="!missingData" class="text-left">
+          <gl-button :href="clustersPath" variant="success">
+            {{ s__('ServerlessDetails|Install Prometheus') }}
+          </gl-button>
+        </div>
+      </div>
+    </div>
+  </div>
+</template>
diff --git a/app/assets/javascripts/serverless/constants.js b/app/assets/javascripts/serverless/constants.js
new file mode 100644
index 00000000000..35f77205f2c
--- /dev/null
+++ b/app/assets/javascripts/serverless/constants.js
@@ -0,0 +1,3 @@
+export const MAX_REQUESTS = 3; // max number of times to retry
+
+export const X_INTERVAL = 5; // Reflects the number of verticle bars on the x-axis
diff --git a/app/assets/javascripts/serverless/serverless_bundle.js b/app/assets/javascripts/serverless/serverless_bundle.js
index 47a510d5fb5..2d3f086ffee 100644
--- a/app/assets/javascripts/serverless/serverless_bundle.js
+++ b/app/assets/javascripts/serverless/serverless_bundle.js
@@ -1,13 +1,7 @@
-import Visibility from 'visibilityjs';
 import Vue from 'vue';
-import { s__ } from '../locale';
-import Flash from '../flash';
-import Poll from '../lib/utils/poll';
-import ServerlessStore from './stores/serverless_store';
-import ServerlessDetailsStore from './stores/serverless_details_store';
-import GetFunctionsService from './services/get_functions_service';
 import Functions from './components/functions.vue';
 import FunctionDetails from './components/function_details.vue';
+import { createStore } from './store';
 
 export default class Serverless {
   constructor() {
@@ -19,10 +13,12 @@ export default class Serverless {
         serviceUrl,
         serviceNamespace,
         servicePodcount,
+        serviceMetricsUrl,
+        prometheus,
+        clustersPath,
+        helpPath,
       } = document.querySelector('.js-serverless-function-details-page').dataset;
       const el = document.querySelector('#js-serverless-function-details');
-      this.store = new ServerlessDetailsStore();
-      const { store } = this;
 
       const service = {
         name: serviceName,
@@ -31,20 +27,19 @@ export default class Serverless {
         url: serviceUrl,
         namespace: serviceNamespace,
         podcount: servicePodcount,
+        metricsUrl: serviceMetricsUrl,
       };
 
-      this.store.updateDetailedFunction(service);
       this.functionDetails = new Vue({
         el,
-        data() {
-          return {
-            state: store.state,
-          };
-        },
+        store: createStore(),
         render(createElement) {
           return createElement(FunctionDetails, {
             props: {
-              func: this.state.functionDetail,
+              func: service,
+              hasPrometheus: prometheus !== undefined,
+              clustersPath,
+              helpPath,
             },
           });
         },
@@ -54,95 +49,27 @@ export default class Serverless {
         '.js-serverless-functions-page',
       ).dataset;
 
-      this.service = new GetFunctionsService(statusPath);
-      this.knativeInstalled = installed !== undefined;
-      this.store = new ServerlessStore(this.knativeInstalled, clustersPath, helpPath);
-      this.initServerless();
-      this.functionLoadCount = 0;
-
-      if (statusPath && this.knativeInstalled) {
-        this.initPolling();
-      }
-    }
-  }
-
-  initServerless() {
-    const { store } = this;
-    const el = document.querySelector('#js-serverless-functions');
-
-    this.functions = new Vue({
-      el,
-      data() {
-        return {
-          state: store.state,
-        };
-      },
-      render(createElement) {
-        return createElement(Functions, {
-          props: {
-            functions: this.state.functions,
-            installed: this.state.installed,
-            clustersPath: this.state.clustersPath,
-            helpPath: this.state.helpPath,
-            loadingData: this.state.loadingData,
-            hasFunctionData: this.state.hasFunctionData,
-          },
-        });
-      },
-    });
-  }
-
-  initPolling() {
-    this.poll = new Poll({
-      resource: this.service,
-      method: 'fetchData',
-      successCallback: data => this.handleSuccess(data),
-      errorCallback: () => Serverless.handleError(),
-    });
-
-    if (!Visibility.hidden()) {
-      this.poll.makeRequest();
-    } else {
-      this.service
-        .fetchData()
-        .then(data => this.handleSuccess(data))
-        .catch(() => Serverless.handleError());
-    }
-
-    Visibility.change(() => {
-      if (!Visibility.hidden() && !this.destroyed) {
-        this.poll.restart();
-      } else {
-        this.poll.stop();
-      }
-    });
-  }
-
-  handleSuccess(data) {
-    if (data.status === 200) {
-      this.store.updateFunctionsFromServer(data.data);
-      this.store.updateLoadingState(false);
-    } else if (data.status === 204) {
-      /* Time out after 3 attempts to retrieve data */
-      this.functionLoadCount += 1;
-      if (this.functionLoadCount === 3) {
-        this.poll.stop();
-        this.store.toggleNoFunctionData();
-      }
+      const el = document.querySelector('#js-serverless-functions');
+      this.functions = new Vue({
+        el,
+        store: createStore(),
+        render(createElement) {
+          return createElement(Functions, {
+            props: {
+              installed: installed !== undefined,
+              clustersPath,
+              helpPath,
+              statusPath,
+            },
+          });
+        },
+      });
     }
   }
 
-  static handleError() {
-    Flash(s__('Serverless|An error occurred while retrieving serverless components'));
-  }
-
   destroy() {
     this.destroyed = true;
 
-    if (this.poll) {
-      this.poll.stop();
-    }
-
     this.functions.$destroy();
     this.functionDetails.$destroy();
   }
diff --git a/app/assets/javascripts/serverless/services/get_functions_service.js b/app/assets/javascripts/serverless/services/get_functions_service.js
deleted file mode 100644
index 303b42dc66c..00000000000
--- a/app/assets/javascripts/serverless/services/get_functions_service.js
+++ /dev/null
@@ -1,11 +0,0 @@
-import axios from '~/lib/utils/axios_utils';
-
-export default class GetFunctionsService {
-  constructor(endpoint) {
-    this.endpoint = endpoint;
-  }
-
-  fetchData() {
-    return axios.get(this.endpoint);
-  }
-}
diff --git a/app/assets/javascripts/serverless/store/actions.js b/app/assets/javascripts/serverless/store/actions.js
new file mode 100644
index 00000000000..826501c9022
--- /dev/null
+++ b/app/assets/javascripts/serverless/store/actions.js
@@ -0,0 +1,113 @@
+import * as types from './mutation_types';
+import axios from '~/lib/utils/axios_utils';
+import statusCodes from '~/lib/utils/http_status';
+import { backOff } from '~/lib/utils/common_utils';
+import createFlash from '~/flash';
+import { MAX_REQUESTS } from '../constants';
+
+export const requestFunctionsLoading = ({ commit }) => commit(types.REQUEST_FUNCTIONS_LOADING);
+export const receiveFunctionsSuccess = ({ commit }, data) =>
+  commit(types.RECEIVE_FUNCTIONS_SUCCESS, data);
+export const receiveFunctionsNoDataSuccess = ({ commit }) =>
+  commit(types.RECEIVE_FUNCTIONS_NODATA_SUCCESS);
+export const receiveFunctionsError = ({ commit }, error) =>
+  commit(types.RECEIVE_FUNCTIONS_ERROR, error);
+
+export const receiveMetricsSuccess = ({ commit }, data) =>
+  commit(types.RECEIVE_METRICS_SUCCESS, data);
+export const receiveMetricsNoPrometheus = ({ commit }) =>
+  commit(types.RECEIVE_METRICS_NO_PROMETHEUS);
+export const receiveMetricsNoDataSuccess = ({ commit }, data) =>
+  commit(types.RECEIVE_METRICS_NODATA_SUCCESS, data);
+export const receiveMetricsError = ({ commit }, error) =>
+  commit(types.RECEIVE_METRICS_ERROR, error);
+
+export const fetchFunctions = ({ dispatch }, { functionsPath }) => {
+  let retryCount = 0;
+
+  dispatch('requestFunctionsLoading');
+
+  backOff((next, stop) => {
+    axios
+      .get(functionsPath)
+      .then(response => {
+        if (response.status === statusCodes.NO_CONTENT) {
+          retryCount += 1;
+          if (retryCount < MAX_REQUESTS) {
+            next();
+          } else {
+            stop(null);
+          }
+        } else {
+          stop(response.data);
+        }
+      })
+      .catch(stop);
+  })
+    .then(data => {
+      if (data !== null) {
+        dispatch('receiveFunctionsSuccess', data);
+      } else {
+        dispatch('receiveFunctionsNoDataSuccess');
+      }
+    })
+    .catch(error => {
+      dispatch('receiveFunctionsError', error);
+      createFlash(error);
+    });
+};
+
+export const fetchMetrics = ({ dispatch }, { metricsPath, hasPrometheus }) => {
+  let retryCount = 0;
+
+  if (!hasPrometheus) {
+    dispatch('receiveMetricsNoPrometheus');
+    return;
+  }
+
+  backOff((next, stop) => {
+    axios
+      .get(metricsPath)
+      .then(response => {
+        if (response.status === statusCodes.NO_CONTENT) {
+          retryCount += 1;
+          if (retryCount < MAX_REQUESTS) {
+            next();
+          } else {
+            dispatch('receiveMetricsNoDataSuccess');
+            stop(null);
+          }
+        } else {
+          stop(response.data);
+        }
+      })
+      .catch(stop);
+  })
+    .then(data => {
+      if (data === null) {
+        return;
+      }
+
+      const updatedMetric = data.metrics;
+      const queries = data.metrics.queries.map(query => ({
+        ...query,
+        result: query.result.map(result => ({
+          ...result,
+          values: result.values.map(([timestamp, value]) => ({
+            time: new Date(timestamp * 1000).toISOString(),
+            value: Number(value),
+          })),
+        })),
+      }));
+
+      updatedMetric.queries = queries;
+      dispatch('receiveMetricsSuccess', updatedMetric);
+    })
+    .catch(error => {
+      dispatch('receiveMetricsError', error);
+      createFlash(error);
+    });
+};
+
+// prevent babel-plugin-rewire from generating an invalid default during karma tests
+export default () => {};
diff --git a/app/assets/javascripts/serverless/store/getters.js b/app/assets/javascripts/serverless/store/getters.js
new file mode 100644
index 00000000000..071f663d9d2
--- /dev/null
+++ b/app/assets/javascripts/serverless/store/getters.js
@@ -0,0 +1,10 @@
+import { translate } from '../utils';
+
+export const hasPrometheusMissingData = state => state.hasPrometheus && !state.hasPrometheusData;
+
+// Convert the function list into a k/v grouping based on the environment scope
+
+export const getFunctions = state => translate(state.functions);
+
+// prevent babel-plugin-rewire from generating an invalid default during karma tests
+export default () => {};
diff --git a/app/assets/javascripts/serverless/store/index.js b/app/assets/javascripts/serverless/store/index.js
new file mode 100644
index 00000000000..5f72060633e
--- /dev/null
+++ b/app/assets/javascripts/serverless/store/index.js
@@ -0,0 +1,18 @@
+import Vue from 'vue';
+import Vuex from 'vuex';
+import * as actions from './actions';
+import * as getters from './getters';
+import mutations from './mutations';
+import createState from './state';
+
+Vue.use(Vuex);
+
+export const createStore = () =>
+  new Vuex.Store({
+    actions,
+    getters,
+    mutations,
+    state: createState(),
+  });
+
+export default createStore();
diff --git a/app/assets/javascripts/serverless/store/mutation_types.js b/app/assets/javascripts/serverless/store/mutation_types.js
new file mode 100644
index 00000000000..25b2f7ac38a
--- /dev/null
+++ b/app/assets/javascripts/serverless/store/mutation_types.js
@@ -0,0 +1,9 @@
+export const REQUEST_FUNCTIONS_LOADING = 'REQUEST_FUNCTIONS_LOADING';
+export const RECEIVE_FUNCTIONS_SUCCESS = 'RECEIVE_FUNCTIONS_SUCCESS';
+export const RECEIVE_FUNCTIONS_NODATA_SUCCESS = 'RECEIVE_FUNCTIONS_NODATA_SUCCESS';
+export const RECEIVE_FUNCTIONS_ERROR = 'RECEIVE_FUNCTIONS_ERROR';
+
+export const RECEIVE_METRICS_NO_PROMETHEUS = 'RECEIVE_METRICS_NO_PROMETHEUS';
+export const RECEIVE_METRICS_SUCCESS = 'RECEIVE_METRICS_SUCCESS';
+export const RECEIVE_METRICS_NODATA_SUCCESS = 'RECEIVE_METRICS_NODATA_SUCCESS';
+export const RECEIVE_METRICS_ERROR = 'RECEIVE_METRICS_ERROR';
diff --git a/app/assets/javascripts/serverless/store/mutations.js b/app/assets/javascripts/serverless/store/mutations.js
new file mode 100644
index 00000000000..991f32a275d
--- /dev/null
+++ b/app/assets/javascripts/serverless/store/mutations.js
@@ -0,0 +1,38 @@
+import * as types from './mutation_types';
+
+export default {
+  [types.REQUEST_FUNCTIONS_LOADING](state) {
+    state.isLoading = true;
+  },
+  [types.RECEIVE_FUNCTIONS_SUCCESS](state, data) {
+    state.functions = data;
+    state.isLoading = false;
+    state.hasFunctionData = true;
+  },
+  [types.RECEIVE_FUNCTIONS_NODATA_SUCCESS](state) {
+    state.isLoading = false;
+    state.hasFunctionData = false;
+  },
+  [types.RECEIVE_FUNCTIONS_ERROR](state, error) {
+    state.error = error;
+    state.hasFunctionData = false;
+    state.isLoading = false;
+  },
+  [types.RECEIVE_METRICS_SUCCESS](state, data) {
+    state.isLoading = false;
+    state.hasPrometheusData = true;
+    state.graphData = data;
+  },
+  [types.RECEIVE_METRICS_NODATA_SUCCESS](state) {
+    state.isLoading = false;
+    state.hasPrometheusData = false;
+  },
+  [types.RECEIVE_METRICS_ERROR](state, error) {
+    state.hasPrometheusData = false;
+    state.error = error;
+  },
+  [types.RECEIVE_METRICS_NO_PROMETHEUS](state) {
+    state.hasPrometheusData = false;
+    state.hasPrometheus = false;
+  },
+};
diff --git a/app/assets/javascripts/serverless/store/state.js b/app/assets/javascripts/serverless/store/state.js
new file mode 100644
index 00000000000..afc3f37d7ba
--- /dev/null
+++ b/app/assets/javascripts/serverless/store/state.js
@@ -0,0 +1,13 @@
+export default () => ({
+  error: null,
+  isLoading: true,
+
+  // functions
+  functions: [],
+  hasFunctionData: true,
+
+  // function_details
+  hasPrometheus: true,
+  hasPrometheusData: false,
+  graphData: {},
+});
diff --git a/app/assets/javascripts/serverless/stores/serverless_details_store.js b/app/assets/javascripts/serverless/stores/serverless_details_store.js
deleted file mode 100644
index 5394d2cded1..00000000000
--- a/app/assets/javascripts/serverless/stores/serverless_details_store.js
+++ /dev/null
@@ -1,11 +0,0 @@
-export default class ServerlessDetailsStore {
-  constructor() {
-    this.state = {
-      functionDetail: {},
-    };
-  }
-
-  updateDetailedFunction(func) {
-    this.state.functionDetail = func;
-  }
-}
diff --git a/app/assets/javascripts/serverless/stores/serverless_store.js b/app/assets/javascripts/serverless/stores/serverless_store.js
deleted file mode 100644
index 816d55a03f9..00000000000
--- a/app/assets/javascripts/serverless/stores/serverless_store.js
+++ /dev/null
@@ -1,29 +0,0 @@
-export default class ServerlessStore {
-  constructor(knativeInstalled = false, clustersPath, helpPath) {
-    this.state = {
-      functions: {},
-      hasFunctionData: true,
-      loadingData: true,
-      installed: knativeInstalled,
-      clustersPath,
-      helpPath,
-    };
-  }
-
-  updateFunctionsFromServer(upstreamFunctions = []) {
-    this.state.functions = upstreamFunctions.reduce((rv, func) => {
-      const envs = rv;
-      envs[func.environment_scope] = (rv[func.environment_scope] || []).concat([func]);
-
-      return envs;
-    }, {});
-  }
-
-  updateLoadingState(loadingData) {
-    this.state.loadingData = loadingData;
-  }
-
-  toggleNoFunctionData() {
-    this.state.hasFunctionData = false;
-  }
-}
diff --git a/app/assets/javascripts/serverless/utils.js b/app/assets/javascripts/serverless/utils.js
new file mode 100644
index 00000000000..8b9e96ce9aa
--- /dev/null
+++ b/app/assets/javascripts/serverless/utils.js
@@ -0,0 +1,23 @@
+// Validate that the object coming in has valid query details and results
+export const validateGraphData = data =>
+  data.queries &&
+  Array.isArray(data.queries) &&
+  data.queries.filter(query => {
+    if (Array.isArray(query.result)) {
+      return query.result.filter(res => Array.isArray(res.values)).length === query.result.length;
+    }
+
+    return false;
+  }).length === data.queries.length;
+
+export const translate = functions =>
+  functions.reduce(
+    (acc, func) =>
+      Object.assign(acc, {
+        [func.environment_scope]: (acc[func.environment_scope] || []).concat([func]),
+      }),
+    {},
+  );
+
+// prevent babel-plugin-rewire from generating an invalid default during karma tests
+export default () => {};
diff --git a/app/controllers/projects/serverless/functions_controller.rb b/app/controllers/projects/serverless/functions_controller.rb
index 39eca10134f..8c3d141c888 100644
--- a/app/controllers/projects/serverless/functions_controller.rb
+++ b/app/controllers/projects/serverless/functions_controller.rb
@@ -7,19 +7,14 @@ module Projects
 
       before_action :authorize_read_cluster!
 
-      INDEX_PRIMING_INTERVAL = 15_000
-      INDEX_POLLING_INTERVAL = 60_000
-
       def index
         respond_to do |format|
           format.json do
             functions = finder.execute
 
             if functions.any?
-              Gitlab::PollingInterval.set_header(response, interval: INDEX_POLLING_INTERVAL)
               render json: serialize_function(functions)
             else
-              Gitlab::PollingInterval.set_header(response, interval: INDEX_PRIMING_INTERVAL)
               head :no_content
             end
           end
@@ -33,6 +28,8 @@ module Projects
 
       def show
         @service = serialize_function(finder.service(params[:environment_id], params[:id]))
+        @prometheus = finder.has_prometheus?(params[:environment_id])
+
         return not_found if @service.nil?
 
         respond_to do |format|
@@ -44,10 +41,24 @@ module Projects
         end
       end
 
+      def metrics
+        respond_to do |format|
+          format.json do
+            metrics = finder.invocation_metrics(params[:environment_id], params[:id])
+
+            if metrics.nil?
+              head :no_content
+            else
+              render json: metrics
+            end
+          end
+        end
+      end
+
       private
 
       def finder
-        Projects::Serverless::FunctionsFinder.new(project.clusters)
+        Projects::Serverless::FunctionsFinder.new(project)
       end
 
       def serialize_function(function)
diff --git a/app/finders/projects/serverless/functions_finder.rb b/app/finders/projects/serverless/functions_finder.rb
index 2f2816a4a08..d9802598c64 100644
--- a/app/finders/projects/serverless/functions_finder.rb
+++ b/app/finders/projects/serverless/functions_finder.rb
@@ -3,8 +3,9 @@
 module Projects
   module Serverless
     class FunctionsFinder
-      def initialize(clusters)
-        @clusters = clusters
+      def initialize(project)
+        @clusters = project.clusters
+        @project = project
       end
 
       def execute
@@ -19,6 +20,23 @@ module Projects
         knative_service(environment_scope, name)&.first
       end
 
+      def invocation_metrics(environment_scope, name)
+        return unless prometheus_adapter&.can_query?
+
+        cluster = clusters_with_knative_installed.preload_knative.find do |c|
+          environment_scope == c.environment_scope
+        end
+
+        func = ::Serverless::Function.new(@project, name, cluster.platform_kubernetes&.actual_namespace)
+        prometheus_adapter.query(:knative_invocation, func)
+      end
+
+      def has_prometheus?(environment_scope)
+        clusters_with_knative_installed.preload_knative.to_a.any? do |cluster|
+          environment_scope == cluster.environment_scope && cluster.application_prometheus_available?
+        end
+      end
+
       private
 
       def knative_service(environment_scope, name)
@@ -55,6 +73,12 @@ module Projects
       def clusters_with_knative_installed
         @clusters.with_knative_installed
       end
+
+      # rubocop: disable CodeReuse/ServiceClass
+      def prometheus_adapter
+        @prometheus_adapter ||= ::Prometheus::AdapterService.new(@project).prometheus_adapter
+      end
+      # rubocop: enable CodeReuse/ServiceClass
     end
   end
 end
diff --git a/app/models/serverless/function.rb b/app/models/serverless/function.rb
new file mode 100644
index 00000000000..5d4f8e0c9e2
--- /dev/null
+++ b/app/models/serverless/function.rb
@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+
+module Serverless
+  class Function
+    attr_accessor :name, :namespace
+
+    def initialize(project, name, namespace)
+      @project = project
+      @name = name
+      @namespace = namespace
+    end
+
+    def id
+      @project.id.to_s + "/" + @name + "/" + @namespace
+    end
+
+    def self.find_by_id(id)
+      array = id.split("/")
+      project = Project.find_by_id(array[0])
+      name = array[1]
+      namespace = array[2]
+
+      self.new(project, name, namespace)
+    end
+  end
+end
diff --git a/app/serializers/projects/serverless/service_entity.rb b/app/serializers/projects/serverless/service_entity.rb
index c98dc1a1c4a..a46f8af1466 100644
--- a/app/serializers/projects/serverless/service_entity.rb
+++ b/app/serializers/projects/serverless/service_entity.rb
@@ -32,6 +32,13 @@ module Projects
         service.dig('podcount')
       end
 
+      expose :metrics_url do |service|
+        project_serverless_metrics_path(
+          request.project,
+          service.dig('environment_scope'),
+          service.dig('metadata', 'name')) + ".json"
+      end
+
       expose :created_at do |service|
         service.dig('metadata', 'creationTimestamp')
       end
diff --git a/app/views/projects/serverless/functions/index.html.haml b/app/views/projects/serverless/functions/index.html.haml
index 635580eac5c..9c69aedfbfc 100644
--- a/app/views/projects/serverless/functions/index.html.haml
+++ b/app/views/projects/serverless/functions/index.html.haml
@@ -5,7 +5,10 @@
 - status_path = project_serverless_functions_path(@project, format: :json)
 - clusters_path = project_clusters_path(@project)
 
-.serverless-functions-page.js-serverless-functions-page{ data: { status_path: status_path, installed: @installed, clusters_path: clusters_path, help_path: help_page_path('user/project/clusters/serverless/index') } }
+.serverless-functions-page.js-serverless-functions-page{ data: { status_path: status_path,
+  installed: @installed,
+  clusters_path: clusters_path,
+  help_path: help_page_path('user/project/clusters/serverless/index') } }
 
 %div{ class: [container_class, ('limit-container-width' unless fluid_layout)] }
   .js-serverless-functions-notice
diff --git a/app/views/projects/serverless/functions/show.html.haml b/app/views/projects/serverless/functions/show.html.haml
index 29737b7014a..d1fe208ce60 100644
--- a/app/views/projects/serverless/functions/show.html.haml
+++ b/app/views/projects/serverless/functions/show.html.haml
@@ -1,14 +1,19 @@
 - @no_container = true
 - @content_class = "limit-container-width" unless fluid_layout
+- clusters_path = project_clusters_path(@project)
+- help_path = help_page_path('user/project/clusters/serverless/index')
 
 - add_to_breadcrumbs('Serverless', project_serverless_functions_path(@project))
 
 - page_title @service[:name]
 
-.serverless-function-details-page.js-serverless-function-details-page{ data: { service: @service.as_json } }
+.serverless-function-details-page.js-serverless-function-details-page{ data: { service: @service.as_json,
+  prometheus: @prometheus,
+  clusters_path: clusters_path,
+  help_path: help_path } }
+
 %div{ class: [container_class, ('limit-container-width' unless fluid_layout)] }
-  .top-area.adjust
-    .serverless-function-details#js-serverless-function-details
+  .serverless-function-details#js-serverless-function-details
 
   .js-serverless-function-notice
     .flash-container