(prometheus) instant query support

public/app/plugins/datasource/prometheus/datasource.ts

@@ -100,6 +100,7 @@ export class PrometheusDatasource {
       var query: any = {};
       query.expr = this.templateSrv.replace(target.expr, options.scopedVars, self.interpolateQueryExpr);
       query.requestId = options.panelId + target.refId;
+      query.format = target.format;
 
       var interval = this.templateSrv.replace(target.interval, options.scopedVars) || options.interval;
       var intervalFactor = target.intervalFactor || 1;
@@ -115,7 +116,11 @@ export class PrometheusDatasource {
     }
 
     var allQueryPromise = _.map(queries, query => {
-      return this.performTimeSeriesQuery(query, start, end);
+      if (query.format === 'time_series') {
+        return this.performTimeSeriesQuery(query, start, end);
+      } else {
+        return this.performInstantQuery(query, end);
+      }
     });
 
     return this.$q.all(allQueryPromise).then(responseList => {
@@ -131,7 +136,11 @@ export class PrometheusDatasource {
           result.push(self.transformMetricDataToTable(response.data.data.result));
         } else {
           for (let metricData of response.data.data.result) {
-            result.push(self.transformMetricData(metricData, activeTargets[index], start, end));
+            if (response.data.data.resultType === 'matrix') {
+              result.push(self.transformMetricData(metricData, activeTargets[index], start, end));
+            } else if (response.data.data.resultType === 'vector') {
+              result.push(self.transformInstantMetricData(metricData, activeTargets[index]));
+            }
           }
         }
       });
@@ -158,6 +167,11 @@ export class PrometheusDatasource {
     return this._request('GET', url, query.requestId);
   }
 
+  performInstantQuery(query, time) {
+    var url = '/api/v1/query?query=' + encodeURIComponent(query.expr) + '&time=' + time;
+    return this._request('GET', url, query.requestId);
+  }
+
   performSuggestQuery(query, cache = false) {
     var url = '/api/v1/label/__name__/values';
 
@@ -342,6 +356,13 @@ export class PrometheusDatasource {
     return table;
   }
 
+  transformInstantMetricData(md, options) {
+    var dps = [], metricLabel = null;
+    metricLabel = this.createMetricLabel(md.metric, options);
+    dps.push([parseFloat(md.value[1]), md.value[0] * 1000]);
+    return { target: metricLabel, datapoints: dps };
+  }
+
   createMetricLabel(labelData, options) {
     if (_.isUndefined(options) || _.isEmpty(options.legendFormat)) {
       return this.getOriginalMetricName(labelData);

public/app/plugins/datasource/prometheus/query_ctrl.ts

@@ -36,6 +36,7 @@ class PrometheusQueryCtrl extends QueryCtrl {
     this.formats = [
       {text: 'Time series', value: 'time_series'},
       {text: 'Table', value: 'table'},
+      {text: 'Instant', value: 'instant'},
     ];
 
     this.updateLink();

public/app/plugins/datasource/prometheus/specs/datasource_specs.ts

@@ -26,7 +26,7 @@ describe('PrometheusDatasource', function() {
                       '&start=1443438675&end=1443460275&step=60';
     var query = {
       range: { from: moment(1443438674760), to: moment(1443460274760) },
-      targets: [{ expr: 'test{job="testjob"}' }],
+      targets: [{ expr: 'test{job="testjob"}', format: 'time_series' }],
       interval: '60s'
     };
     var response = {
@@ -62,7 +62,7 @@ describe('PrometheusDatasource', function() {
                       '&start=' + start + '&end=' + end + '&step=' + step;
     var query = {
       range: { from: moment(1443438674760), to: moment(1443460274760) },
-      targets: [{ expr: 'test{job="testjob"}' }],
+      targets: [{ expr: 'test{job="testjob"}', format: 'time_series' }],
       interval: '60s'
     };
     var response = {
@@ -119,7 +119,40 @@ describe('PrometheusDatasource', function() {
       expect(results.data[1].datapoints[3][0]).to.be(null);
     });
   });
-  describe('When performing annotationQuery', function() {
+  describe('When querying prometheus with one target and format = instant', function () {
+    var results;
+    var urlExpected = 'proxied/api/v1/query?query=' +
+      encodeURIComponent('test{job="testjob"}') +
+      '&time=1443460275';
+    var query = {
+      range: { from: moment(1443438674760), to: moment(1443460274760) },
+      targets: [{ expr: 'test{job="testjob"}', format: 'instant' }],
+      interval: '60s'
+    };
+    var response = {
+      status: "success",
+      data: {
+        resultType: "vector",
+        result: [{
+          metric: { "__name__": "test", job: "testjob" },
+          value: [1443454528, "3846"]
+        }]
+      }
+    };
+    beforeEach(function () {
+      ctx.$httpBackend.expect('GET', urlExpected).respond(response);
+      ctx.ds.query(query).then(function (data) { results = data; });
+      ctx.$httpBackend.flush();
+    });
+    it('should generate the correct query', function () {
+      ctx.$httpBackend.verifyNoOutstandingExpectation();
+    });
+    it('should return series list', function () {
+      expect(results.data.length).to.be(1);
+      expect(results.data[0].target).to.be('test{job="testjob"}');
+    });
+  });
+  describe('When performing annotationQuery', function () {
     var results;
     var urlExpected = 'proxied/api/v1/query_range?query=' +
                       encodeURIComponent('ALERTS{alertstate="firing"}') +