Merge pull request #6971 from TerriaJS/mapserver-emptylayers-precached

`ArcGisMapServerCatalogItem` will now use "pre-cached tiles" if no `layers` are specified.

CHANGES.md

@@ -3,6 +3,7 @@
 #### next release (8.3.10)
 
 - Added `apiColumns` to `ApiTableCatalogItem` - this can now be used to specify `responseDataPath` per table column.
+- `ArcGisMapServerCatalogItem` will now use "pre-cached tiles" if available if no (or all) `layers` are specified.
 - [The next improvement]
 
 #### 8.3.9 - 2023-11-24

lib/Core/arraysAreEqual.ts

@@ -0,0 +1,19 @@
+import isDefined from "./isDefined";
+
+export default function arraysAreEqual<T>(left: T[], right: T[]) {
+  if (left === right) {
+    return true;
+  }
+
+  if (!isDefined(left) || !isDefined(right) || left.length !== right.length) {
+    return false;
+  }
+
+  for (var i = 0; i < left.length; ++i) {
+    if (left[i] !== right[i]) {
+      return false;
+    }
+  }
+
+  return true;
+}

lib/Core/setsAreEqual.ts

@@ -0,0 +1,17 @@
+export function setsAreEqual<T>(left: Set<T> | T[], right: Set<T> | T[]) {
+  if (Array.isArray(left)) left = new Set(left);
+
+  if (Array.isArray(right)) right = new Set(right);
+
+  if (left === right) {
+    return true;
+  }
+
+  if (left.size !== right.size) {
+    return false;
+  }
+
+  const union = new Set([...left, ...right]);
+
+  return union.size === left.size && union.size === right.size;
+}

lib/Models/Catalog/Esri/ArcGisMapServerCatalogItem.ts

@@ -1,17 +1,19 @@
 import i18next from "i18next";
 import uniqWith from "lodash-es/uniqWith";
 import { computed, makeObservable, override, runInAction } from "mobx";
+import moment from "moment";
 import WebMercatorTilingScheme from "terriajs-cesium/Source/Core/WebMercatorTilingScheme";
 import ArcGisMapServerImageryProvider from "terriajs-cesium/Source/Scene/ArcGisMapServerImageryProvider";
 import URI from "urijs";
+import TerriaError, { networkRequestError } from "../../../Core/TerriaError";
 import createDiscreteTimesFromIsoSegments from "../../../Core/createDiscreteTimes";
 import createTransformerAllowUndefined from "../../../Core/createTransformerAllowUndefined";
 import filterOutUndefined from "../../../Core/filterOutUndefined";
 import isDefined from "../../../Core/isDefined";
 import loadJson from "../../../Core/loadJson";
 import replaceUnderscores from "../../../Core/replaceUnderscores";
 import { scaleDenominatorToLevel } from "../../../Core/scaleToDenominator";
-import TerriaError, { networkRequestError } from "../../../Core/TerriaError";
+import { setsAreEqual } from "../../../Core/setsAreEqual";
 import Proj4Definitions from "../../../Map/Vector/Proj4Definitions";
 import CatalogMemberMixin from "../../../ModelMixins/CatalogMemberMixin";
 import DiscretelyTimeVaryingMixin from "../../../ModelMixins/DiscretelyTimeVaryingMixin";
@@ -27,16 +29,15 @@ import LegendTraits, {
 } from "../../../Traits/TraitsClasses/LegendTraits";
 import { RectangleTraits } from "../../../Traits/TraitsClasses/MappableTraits";
 import CreateModel from "../../Definition/CreateModel";
-import createStratumInstance from "../../Definition/createStratumInstance";
 import LoadableStratum from "../../Definition/LoadableStratum";
 import { BaseModel, ModelConstructorParameters } from "../../Definition/Model";
 import StratumFromTraits from "../../Definition/StratumFromTraits";
 import StratumOrder from "../../Definition/StratumOrder";
+import createStratumInstance from "../../Definition/createStratumInstance";
 import getToken from "../../getToken";
 import proxyCatalogItemUrl from "../proxyCatalogItemUrl";
 import MinMaxLevelMixin from "./../../../ModelMixins/MinMaxLevelMixin";
 import { Extent, Layer, MapServer } from "./ArcGisInterfaces";
-import moment from "moment";
 
 const proj4 = require("proj4").default;
 
@@ -552,7 +553,13 @@ export default class ArcGisMapServerCatalogItem extends UrlMixin(
         /** Only used "pre-cached" tiles if we aren't requesting any specific layers
          * If the `layersArray` property is specified, we request individual dynamic layers and ignore the fused map cache.
          */
-        usePreCachedTilesIfAvailable: this.layersArray.length == 0,
+        usePreCachedTilesIfAvailable:
+          this.layersArray.length === 0 ||
+          !this.layers ||
+          setsAreEqual(
+            this.layersArray.map((l) => l.id),
+            stratum.allLayers.map((l) => l.id)
+          ),
         mapServerData: stratum.mapServer,
         token: stratum.token,
         credit: this.attribution

test/Models/Catalog/esri/ArcGisMapServerCatalogItemSpec.ts

@@ -262,6 +262,62 @@ describe("ArcGisMapServerCatalogItem", function () {
           imageryProvider.requestImage(0, 0, 100);
           expect(item.scaleWorkbenchInfo).toBeDefined();
         });
+
+        it("usePreCachedTilesIfAvailable = false if requesting specific layers", async function () {
+          runInAction(() => {
+            item = new ArcGisMapServerCatalogItem("test", new Terria());
+            item.setTrait(CommonStrata.definition, "url", mapServerUrl);
+            item.setTrait(CommonStrata.definition, "layers", "31,32");
+          });
+          await item.loadMapItems();
+
+          expect(item.layersArray.length).toBe(2);
+
+          imageryProvider = item.mapItems[0]
+            .imageryProvider as ArcGisMapServerImageryProvider;
+          expect((imageryProvider as any)._usePreCachedTilesIfAvailable).toBe(
+            false
+          );
+        });
+
+        it("usePreCachedTilesIfAvailable = true if not requesting specific layers", async function () {
+          runInAction(() => {
+            item = new ArcGisMapServerCatalogItem("test", new Terria());
+            item.setTrait(CommonStrata.definition, "url", mapServerUrl);
+            item.setTrait(CommonStrata.definition, "layers", undefined);
+          });
+          await item.loadMapItems();
+          expect(item.layersArray.length).toBe(74);
+
+          imageryProvider = item.mapItems[0]
+            .imageryProvider as ArcGisMapServerImageryProvider;
+          expect((imageryProvider as any)._usePreCachedTilesIfAvailable).toBe(
+            true
+          );
+        });
+
+        it("usePreCachedTilesIfAvailable = true if requesting all layers", async function () {
+          runInAction(() => {
+            item = new ArcGisMapServerCatalogItem("test", new Terria());
+            item.setTrait(CommonStrata.definition, "url", mapServerUrl);
+            item.setTrait(
+              CommonStrata.definition,
+              "layers",
+              new Array(74)
+                .fill(0)
+                .map((_, i) => i)
+                .join(",")
+            );
+          });
+          await item.loadMapItems();
+          expect(item.layersArray.length).toBe(74);
+
+          imageryProvider = item.mapItems[0]
+            .imageryProvider as ArcGisMapServerImageryProvider;
+          expect((imageryProvider as any)._usePreCachedTilesIfAvailable).toBe(
+            true
+          );
+        });
       });
     });