GetNonIntersectedSpans refactoring (#751)

server/spec/models/detection_model.jest.ts

@@ -1,5 +1,5 @@
 import { TEST_ANALYTIC_UNIT_ID } from '../utils_for_tests/analytic_units';
-import { buildSpans, insertSpans, clearSpansDB, convertSpansToOptions } from '../utils_for_tests/detection_spans';
+import { insertSpans, clearSpansDB, convertSpansToOptions } from '../utils_for_tests/detection_spans';
 
 import * as Detection from '../../src/models/detection_model';
 
@@ -67,9 +67,3 @@ describe('getIntersectedSpans', () => {
   });
 });
 
-describe('getSpanBorders', () => {
-  it('should sort and find span borders', () => {
-    const borders = Detection.getSpanBorders(buildSpans(INITIAL_SPANS_CONFIGS));
-    expect(borders).toEqual([1, 3, 3, 4]);
-  });
-});

server/spec/utils/spans.jest.ts

@@ -1,35 +1,51 @@
-import { getNonIntersectedSpans } from '../../src/utils/spans';
+import { cutSpanWithSpans } from '../../src/utils/spans';
 
 import 'jest';
 
-describe('getNonIntersectedSpans', function() {
-
-  let spanBorders = [3, 5, 6, 8, 10, 20];
-  
-  it('functional test', function() {  
-    expect(getNonIntersectedSpans(4, 11, spanBorders)).toEqual([{from: 5, to: 6}, {from: 8, to: 10}]);
-    expect(getNonIntersectedSpans(5, 11, spanBorders)).toEqual([{from: 5, to: 6}, {from: 8, to: 10}]);
-    expect(getNonIntersectedSpans(4, 10, spanBorders)).toEqual([{from: 5, to: 6}, {from: 8, to: 10}]);
-    expect(getNonIntersectedSpans(5, 10, spanBorders)).toEqual([{from: 5, to: 6}, {from: 8, to: 10}]);
-    expect(getNonIntersectedSpans(4, 20, spanBorders)).toEqual([{from: 5, to: 6}, {from: 8, to: 10}]);
-    expect(getNonIntersectedSpans(4, 21, spanBorders)).toEqual([{from: 5, to: 6}, {from: 8, to: 10}, {from: 20, to: 21}]);
-    expect(getNonIntersectedSpans(2, 20, spanBorders)).toEqual([{from: 2, to: 3}, {from: 5, to: 6}, {from: 8, to: 10}]);
-    expect(getNonIntersectedSpans(2, 21, spanBorders)).toEqual([{from: 2, to: 3}, {from: 5, to: 6}, {from: 8, to: 10}, {from: 20, to: 21}]);
-    expect(getNonIntersectedSpans(3, 11, spanBorders)).toEqual([{from: 5, to: 6}, {from: 8, to: 10}]);
-    expect(getNonIntersectedSpans(3, 20, spanBorders)).toEqual([{from: 5, to: 6}, {from: 8, to: 10}]);
-    expect(getNonIntersectedSpans(3, 20, spanBorders)).toEqual([{from: 5, to: 6}, {from: 8, to: 10}]);
-    expect(getNonIntersectedSpans(4, 7, [3, 5, 6, 8])).toEqual([{from: 5, to: 6}]);
+
+function cutSpan(from: number, to: number, cuts: [number, number][]): [number, number][] {
+  return cutSpanWithSpans(
+    { from: from, to: to },
+    cuts.map(([from, to]) => ({ from, to }))
+  ).map(({ from, to }) => [from, to]);
+}
+
+describe('cutSpanWithSpans', function() {
+
+  it('should find spans in simple non-intersected borders', function() {
+    let cutSpans = [[3, 5], [6, 8], [10, 20]] as [number, number][];
+
+    expect(cutSpan(4, 11, cutSpans)).toEqual([[5, 6], [8, 10]]);
+    expect(cutSpan(5, 11, cutSpans)).toEqual([[5, 6], [8, 10]]);
+    expect(cutSpan(4, 10, cutSpans)).toEqual([[5, 6], [8, 10]]);
+    expect(cutSpan(5, 10, cutSpans)).toEqual([[5, 6], [8, 10]]);
+    expect(cutSpan(4, 20, cutSpans)).toEqual([[5, 6], [8, 10]]);
+    expect(cutSpan(4, 21, cutSpans)).toEqual([[5, 6], [8, 10], [20, 21]]);
+    expect(cutSpan(2, 20, cutSpans)).toEqual([[2, 3], [5, 6], [8, 10]]);
+    expect(cutSpan(2, 21, cutSpans)).toEqual([[2, 3], [5, 6], [8, 10], [20, 21]]);
+    expect(cutSpan(3, 11, cutSpans)).toEqual([[5, 6], [8, 10]]);
+    expect(cutSpan(3, 20, cutSpans)).toEqual([[5, 6], [8, 10]]);
+    expect(cutSpan(4, 7, [[3, 5], [6, 8]])).toEqual([[5, 6]]);
+  });
+
+  it('should handle empty input spans list case', function() {
+    expect(cutSpan(4, 10, [])).toEqual([[4, 10]]);
+  });
+
+  it('should handle case when from and to are inside of one big span', function() {
+    expect(cutSpan(4, 10, [[1, 20]])).toEqual([]);
+    expect(cutSpan(4, 10, [[1, 10]])).toEqual([]);
+    expect(cutSpan(4, 10, [[4, 20]])).toEqual([]);
+    expect(cutSpan(4, 10, [[4, 10]])).toEqual([]);
   });
 
-  it('empty borders list', function() {
-    expect(getNonIntersectedSpans(4, 10, [])).toEqual([]);
+  it('should be ready to get not-sorted cuts', function() {
+    expect(cutSpan(0, 20, [[3, 5], [1, 2]])).toEqual([[0, 1], [2, 3], [5, 20]]);
+    expect(cutSpan(0, 20, [[3, 5], [1, 2], [0.1, 0.5]])).toEqual([[0, 0.1], [0.5, 1], [2, 3], [5, 20]]);
   });
 
-  it('all in span', function() {
-    expect(getNonIntersectedSpans(4, 10, [1, 20])).toEqual([]);
-    expect(getNonIntersectedSpans(4, 10, [1, 10])).toEqual([]);
-    expect(getNonIntersectedSpans(4, 10, [4, 20])).toEqual([]);
-    expect(getNonIntersectedSpans(4, 10, [4, 10])).toEqual([]);
+  it('should be ready to get overlayed cuts', function() {
+    expect(cutSpan(0, 20, [[3, 5], [4, 10]])).toEqual([[0,3], [10, 20]]);
   });
 
 });

server/src/controllers/analytics_controller.ts

@@ -10,7 +10,7 @@ import { AlertService } from '../services/alert_service';
 import { HASTIC_API_KEY } from '../config';
 import { DataPuller } from '../services/data_puller';
 import { getGrafanaUrl } from '../utils/grafana';
-import { getNonIntersectedSpans } from '../utils/spans';
+import { cutSpanWithSpans } from '../utils/spans';
 
 import { queryByMetric, GrafanaUnavailable, DatasourceUnavailable } from 'grafana-datasource-kit';
 
@@ -564,9 +564,7 @@ export async function getDetectionSpans(
     }
   }
 
-  const spanBorders = Detection.getSpanBorders(readySpans);
-
-  let newDetectionSpans = getNonIntersectedSpans(from, to, spanBorders);
+  let newDetectionSpans = cutSpanWithSpans({ from, to }, readySpans);
   if(newDetectionSpans.length === 0) {
     return [ new Detection.DetectionSpan(analyticUnitId, from, to, Detection.DetectionStatus.READY) ];
   }

server/src/models/detection_model.ts

@@ -2,7 +2,6 @@ import { AnalyticUnitId } from './analytic_units';
 import { Collection, makeDBQ } from '../services/data_service';
 
 import * as _ from 'lodash';
-import { getNonIntersectedSpans } from '../utils/spans';
 
 let db = makeDBQ(Collection.DETECTION_SPANS);
 
@@ -137,22 +136,6 @@ export async function insertSpan(span: DetectionSpan) {
   return db.insertOne(spanToInsert);
 }
 
-/**
- * Sorts spans by `from` field and @returns an array of their borders 
- */
-// TODO: remove after getNonIntersectedSpans refactoring
-export function getSpanBorders(spans: DetectionSpan[]): number[] {
-  let spanBorders: number[] = [];
-
-  _.sortBy(spans.map(span => span.toObject()), 'from')
-    .forEach(span => {
-      spanBorders.push(span.from);
-      spanBorders.push(span.to);
-    });
-
-  return spanBorders;
-}
-
 export function clearSpans(analyticUnitId: AnalyticUnitId) {
   return db.removeMany({ analyticUnitId });
 }

server/src/utils/spans.ts

@@ -2,53 +2,62 @@
 
 import * as _ from 'lodash';
 
+
 export declare type Span = {
   from: number,
   to: number
 }
 
-// TODO: move from utils and refactor
-export function getNonIntersectedSpans(from: number, to: number, spanBorders: number[]): Span[] {
-  // spanBorders array must be sorted ascending
-  let isFromProcessed = false;
-  let alreadyDetected = false;
-  let startDetectionRange = null;
-  let result: Span[] = [];
-
-  for(var border of spanBorders) {
-    if(!isFromProcessed && border >= from) {
-      isFromProcessed = true;
-      if(border === from) {
-        if(alreadyDetected) {
-          startDetectionRange = from;
-        }
-      } else {
-          if(!alreadyDetected) {
-          startDetectionRange = from;
-        }
-      }
-    }
+// TODO: move from utils and use generator
+/**
+ *
+ * @param inputSpan a big span which we will cut
+ * @param cutSpans spans which to cut the inputSpan. Spans can overlay.
+ *
+ * @returns array of spans which are holes
+ */
+export function cutSpanWithSpans(inputSpan: Span, cutSpans: Span[]): Span[] {
+  if(cutSpans.length === 0) {
+    return [inputSpan];
+  }
 
-    if(border >= to) {
-      if(!alreadyDetected) {
-        result.push({ from: startDetectionRange, to });
+  // we sort and merge out cuts to normalize it
+  cutSpans = _.sortBy(cutSpans, s => s.from);
+  var mergedSortedCuts =_.reduce(cutSpans, 
+    ((acc: Span[], s: Span) => {
+      if(acc.length === 0) return [s];
+      let last = acc[acc.length - 1];
+      if(s.to <= last.to) return acc;
+      if(s.from <= last.to) {
+        last.to = s.to;
+        return acc;
       }
-      break;
+      acc.push(s);
+      return acc;
+    }), []
+  );
+
+  // this is what we get if we cut `mergedSortedCuts` from (-Infinity, Infinity)
+  var holes = mergedSortedCuts.map((cut, i) => {
+    let from = -Infinity;
+    let to = cutSpans[0].from;
+    if(i > 0) {
+      from = mergedSortedCuts[i - 1].to;
+      to = cut.from;
     }
-
-    if(alreadyDetected) { //end of already detected region, start point for new detection
-      startDetectionRange = border;
-    } else { //end of new detection region
-      if(startDetectionRange !== null) {
-        result.push({ from: startDetectionRange, to: border});
-      }
+    return { from, to }
+  }).concat({
+    from: mergedSortedCuts[mergedSortedCuts.length - 1].to,
+    to: Infinity
+  });
+
+  return _(holes).map(c => {
+    if(c.to <= inputSpan.from) return undefined;
+    if(inputSpan.to <= c.from) return undefined;
+    return {
+      from: Math.max(c.from, inputSpan.from),
+      to: Math.min(c.to, inputSpan.to),
     }
-    alreadyDetected = !alreadyDetected;
-  }
-
-  if(border < to) {
-    result.push({ from: startDetectionRange, to });
-  }
+  }).compact().value();
 
-  return result;
 }