Tutorial: Query features (spatial)

Learn how to execute a spatial query to access polygon features from a feature service.

Make a spatial query using API key authentication

A feature layer can contain a large number of features stored in ArcGIS. To access a subset of these features, you can execute an SQL or spatial query, either together or individually. The results can contain the attributes, geometry, or both for each record. SQL and spatial queries are useful when a feature layer is very large and you want to access only a subset of its data.

In this tutorial, you sketch a feature on the map and use ArcGIS REST JS to perform a spatial query against the LA County Parcels hosted feature layer. The layer contains ±2.4 million features. The spatial query returns all of the parcels that intersect the sketched feature.

Prerequisites

An ArcGIS Location Platform or ArcGIS Online account.

Steps

Get the starter app

Select a type of authentication below and follow the steps to create a new application.

You can choose one of the following to create a new CodePen:

Option 1: Complete the Display a scene tutorial; or,
Option 2: Start from the Display a scene tutorial .

Set up authentication

Create developer credentials in your portal for the type of authentication you selected.

Create a new API key credential with the correct privileges to access the resources used in this tutorial.

Go to the Create an API key tutorial and create an API key with the following privilege(s):
- Privileges
  - Location services > Basemaps
Copy the API key access token to your clipboard when prompted.

Set developer credentials

Use the API key or OAuth developer credentials created in the previous step in your application.

Add <script> elements in the HTML <body> and create an accessToken variable to store your access token. Set YOUR_ACCESS_TOKEN with the access token you previously copied from your API key credentials.

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  <script>

    /* Use for API key authentication */
    const accessToken = "YOUR_ACCESS_TOKEN";

  </script>
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Set the defaultAccessToken included with Cesium to authenticate requests to the ArcGIS services used in this tutorial.

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  <script>

    /* Use for API key authentication */
    const accessToken = "YOUR_ACCESS_TOKEN";

    Cesium.ArcGisMapService.defaultAccessToken = accessToken;

  </script>
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In both the index.html and callback.html files, set the properties of clientId and redirectUri with the client ID and redirect URL of your OAuth credentials.

index.html
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    /* Use for user authentication */
    const clientId = "YOUR_CLIENT_ID"; // Your client ID from OAuth credentials
    const redirectUri = "YOUR_REDIRECT_URI"; // The redirect URL registered in your OAuth credentials
    const session = await arcgisRest.ArcGISIdentityManager.beginOAuth2({
      clientId,
      redirectUri,
      portal: "https://www.arcgis.com/sharing/rest" // Your portal URL
    })

    const accessToken = session.token;

callback.html
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    arcgisRest.ArcGISIdentityManager.completeOAuth2({
      clientId: "YOUR_CLIENT_ID", // Your client ID from OAuth credentials
      redirectUri: "YOUR_REDIRECT_URI", // The redirect URL registered in your OAuth credentials
      portal: "https://www.arcgis.com/sharing/rest" // Your portal URL
    })

Run the app and ensure you can sign in successfully.

If you are unable to sign in, make sure you have the correct redirect URL and port. This URL varies based on your application and typically takes the format of https://<server>[:port]/callback.html or http://my-arcgis-app:/auth. For example, if you are running an application on http://127.0.0.1:5500/, set http://127.0.0.1:5500/callback.html as your redirect URL in the index.html and callback.html file and your developer credential. They all have to match!

Set the defaultAccessToken included with Cesium to authenticate requests to the ArcGIS services used in this tutorial.

index.html
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    Cesium.ArcGisMapService.defaultAccessToken = accessToken;

Get a Cesium ion access token

All Cesium applications must use an access token provided through Cesium ion. This token allows you to access assets such as Cesium World Terrain in your application.

Go to your Cesium ion dashboard to generate an access token. Copy the key to your clipboard.

Create a cesiumAccessToken variable and replace YOUR_CESIUM_ACCESS_TOKEN with the access token you copied from the Cesium ion dashboard.

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  <script>

    /* Use for API key authentication */
    const accessToken = "YOUR_ACCESS_TOKEN";

    // or

    /* Use for user authentication */
    // const session = await arcgisRest.ArcGISIdentityManager.beginOAuth2({
    //   clientId: "YOUR_CLIENT_ID", // Your client ID from OAuth credentials
    //   redirectUri: "YOUR_REDIRECT_URI", // The redirect URL registered in your OAuth credentials
    //   portal: "YOUR_PORTAL_URL" // Your portal URL
    // })

    // const accessToken = session.token;

    Cesium.ArcGisMapService.defaultAccessToken = accessToken;

    const cesiumAccessToken = "YOUR_CESIUM_ACCESS_TOKEN";

  </script>

Configure Cesium.Ion.defaultAccessToken with the Cesium access token to validate the application.

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  <script>

    /* Use for API key authentication */
    const accessToken = "YOUR_ACCESS_TOKEN";

    // or

    /* Use for user authentication */
    // const session = await arcgisRest.ArcGISIdentityManager.beginOAuth2({
    //   clientId: "YOUR_CLIENT_ID", // Your client ID from OAuth credentials
    //   redirectUri: "YOUR_REDIRECT_URI", // The redirect URL registered in your OAuth credentials
    //   portal: "YOUR_PORTAL_URL" // Your portal URL
    // })

    // const accessToken = session.token;

    Cesium.ArcGisMapService.defaultAccessToken = accessToken;

    const cesiumAccessToken = "YOUR_CESIUM_ACCESS_TOKEN";

    Cesium.Ion.defaultAccessToken = cesiumAccessToken;

  </script>

Add references to ArcGIS REST JS

In the <head> element, reference the feature-service and request packages from ArcGIS REST JS.

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    <script src="https://cesium.com/downloads/cesiumjs/releases/1.125/Build/Cesium/Cesium.js"></script>
    <link href="https://cesium.com/downloads/cesiumjs/releases/1.125/Build/Cesium/Widgets/widgets.css" rel="stylesheet">

    <script src="https://unpkg.com/@esri/arcgis-rest-request@4/dist/bundled/request.umd.js"></script>
    <script src="https://unpkg.com/@esri/arcgis-rest-feature-service@4/dist/bundled/feature-service.umd.js"></script>

In the <body>, create an arcgisRest.ApiKeyManager using your access token to authenticate requests to the feature service.

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    /* Use for API key authentication */
    const accessToken = "YOUR_ACCESS_TOKEN";

    // or

    /* Use for user authentication */
    // const session = await arcgisRest.ArcGISIdentityManager.beginOAuth2({
    //   clientId: "YOUR_CLIENT_ID", // Your client ID from OAuth credentials
    //   redirectUri: "YOUR_REDIRECT_URI", // The redirect URL registered in your OAuth credentials
    //   portal: "YOUR_PORTAL_URL" // Your portal URL
    // })

    // const accessToken = session.token;

    Cesium.ArcGisMapService.defaultAccessToken = accessToken;

    const authentication = arcgisRest.ApiKeyManager.fromKey(accessToken);

Create a drawing mode selector

Create a <select> HTML element to provide a list of spatial operations for drawing features such as points, lines, or polygons.

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    <div id="cesiumContainer"></div>

    <select id="mode-select">
        <option value="">Choose a type of feature to draw...</option>
        <option value="Point">Draw point</option>
        <option value="Polyline">Draw line</option>
        <option value="Polygon" selected>Draw polygon</option>
    </select>

Style the <select> element so that it displays properly in your application.

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    <script src="https://unpkg.com/@terraformer/arcgis@2.0.7/dist/t-arcgis.umd.js"></script>
    <style>
        html,
        body,
        #cesiumContainer {
            width: 100%;
            height: 100%;
            padding: 0px;
            margin: 0px;
        }

        #mode-select {
            position: absolute;
            top: 8px;
            left: 8px;
            padding: 4px 8px;
            font-size: 16px;
            border-radius: 0;
        }

    </style>

Add a feature layer

Reference the LA County Parcels hosted feature layer in your application to perform a spatial query against. The layer contains ±2.4 million features. The spatial query returns all of the parcels that intersect the sketched feature.

Copy the URL of the LA County Parcels feature layer.

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        const layerName = "LA_County_Parcels";
        const layerURL = "https://services3.arcgis.com/GVgbJbqm8hXASVYi/arcgis/rest/services/" + layerName + "/FeatureServer/0";
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Add the data attribution for the feature layer source.

Go to the LA County Parcels item.
Scroll down to the Credits (Attribution) section and copy its value.

Create an attribution property and paste the attribution value from the item.

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        // Attribution text retrieved from https://arcgis.com/home/item.html?id=a6fdf2ee0e454393a53ba32b9838b303
        viewer.creditDisplay.addStaticCredit(new Cesium.Credit("County of Los Angeles Office of the Assessor", false));
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Create drawing tools

A spatial query is performed by passing a geometry object to a hosted feature layer. Add tools that allow the user of your app to draw point, line, and polygon geometries on the map.

Add methods to draw points, lines, and polygons on the map. The methods will be called based on the drawing mode the user selects.

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        if (!viewer.scene.pickPositionSupported) {
            window.alert("This browser does not support pickPosition.");
        }

        viewer.cesiumWidget.screenSpaceEventHandler.removeInputAction(
            Cesium.ScreenSpaceEventType.LEFT_DOUBLE_CLICK
        );
        function createPoint(worldPosition) {
            const point = viewer.entities.add({
                position: worldPosition,
                point: {
                    color: Cesium.Color.WHITE,
                    pixelSize: 5,
                    heightReference: Cesium.HeightReference.CLAMP_TO_GROUND,
                },
            });
            return point;
        }
        let drawingMode;
        function drawShape(positionData) {
            let shape;
            if (drawingMode === "Polyline") {
                shape = viewer.entities.add({
                    polyline: {
                        positions: positionData,
                        clampToGround: true,
                        width: 3,
                    },
                });
            }
            else if (drawingMode === "Polygon") {
                shape = viewer.entities.add({
                    polygon: {
                        hierarchy: positionData,
                        outline: true,
                        outlineWidth: 10,
                        material: new Cesium.ColorMaterialProperty(
                            Cesium.Color.WHITE.withAlpha(0.4)
                        ),
                    },
                });
            }
            return shape;
        }
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Set up event handlers to initiate drawing in the selected mode (point, polyline, or polygon) when the user clicks. Dynamically update the shape based on mouse clicks and movements.

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        let activeShapePoints = [];
        let activeShape;
        let floatingPoint;
        let newShape = true;

        const handler = new Cesium.ScreenSpaceEventHandler(viewer.canvas);
        handler.setInputAction(function (event) {
            if (!drawingMode) return;
            if (newShape) {
                viewer.entities.removeAll();
                newShape = false;
            }

            const earthPosition = viewer.camera.pickEllipsoid(event.position);
            // `earthPosition` will be undefined if our mouse is not over the globe.
            if (Cesium.defined(earthPosition)) {
                // Points
                if (drawingMode === "Point") {
                    activeShapePoints.push(earthPosition);
                    createPoint(earthPosition);
                    performQuery()
                }
                // Lines and polygons
                else {
                    if (activeShapePoints.length === 0) {
                        floatingPoint = createPoint(earthPosition);
                        activeShapePoints.push(earthPosition);
                        const dynamicPositions = new Cesium.CallbackProperty(function () {
                            if (drawingMode === "Polygon") {
                                return new Cesium.PolygonHierarchy(activeShapePoints);
                            }
                            return activeShapePoints;
                        }, false);
                        activeShape = drawShape(dynamicPositions);
                    }
                    activeShapePoints.push(earthPosition);
                    createPoint(earthPosition);
                }
            }
        }, Cesium.ScreenSpaceEventType.LEFT_CLICK);

        handler.setInputAction(function (event) {
            if (Cesium.defined(floatingPoint)) {
                const newPosition = viewer.camera.pickEllipsoid(event.endPosition);
                if (Cesium.defined(newPosition)) {
                    floatingPoint.position.setValue(newPosition);
                    activeShapePoints.pop();
                    activeShapePoints.push(newPosition);
                }
            }
        }, Cesium.ScreenSpaceEventType.MOUSE_MOVE);
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Add code to terminate the drawing when the user double clicks.

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        handler.setInputAction(function (event) {
            if (Cesium.defined(floatingPoint)) {
                const newPosition = viewer.camera.pickEllipsoid(event.endPosition);
                if (Cesium.defined(newPosition)) {
                    floatingPoint.position.setValue(newPosition);
                    activeShapePoints.pop();
                    activeShapePoints.push(newPosition);
                }
            }
        }, Cesium.ScreenSpaceEventType.MOUSE_MOVE);

        // Redraw the shape so it's not dynamic and remove the dynamic shape.
        function terminateShape() {
            viewer.entities.remove(floatingPoint);
            viewer.entities.remove(activeShape);
            floatingPoint = undefined;
            activeShape = undefined;
            activeShapePoints = [];
            newShape = true;
        }

        // Event listeners
        handler.setInputAction(function (event) {
            if (drawingMode === "Point" || !drawingMode) return;
            activeShapePoints.pop();

        }, Cesium.ScreenSpaceEventType.LEFT_DOUBLE_CLICK);

        const select = document.getElementById("mode-select");
        select.addEventListener("change", () => {
            terminateShape();
            viewer.entities.removeAll();
            drawingMode = select.value;
        })
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Create a helper function that converts the resulting geometries into ArcGIS format. This will be used to query the feature layer.

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        // Process features
        function getArcGISFeature(points) {
            //convert each point to cartesian latlng
            const degrees = []
            for (point of points) {
                const cartographic = Cesium.Cartographic.fromCartesian(point);
                degrees.push([Cesium.Math.toDegrees(cartographic.longitude), Cesium.Math.toDegrees(cartographic.latitude)]);
            }
            let coords;
            let type = drawingMode;
            if (drawingMode === "Point") {
                coords = degrees[0];
            }
            else if (drawingMode === "Polyline") {
                type = "LineString";
                coords = degrees;
            }
            else {
                coords = [degrees];
            }

            const result = Terraformer.geojsonToArcGIS({
                "coordinates": coords,
                "type": type
            })

            return result;

        }
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Query the feature layer

Create an executeQuery function that uses arcgisRest.queryFeatures to query the LA County Parcels feature layer with a geometry. Set the spatialRel parameter of the request to esriSpatialRelIntersects to find parcels that intersect the geometry.

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        function executeQuery(geometry) {

            arcgisRest.queryFeatures({
                url: layerURL,
                authentication,
                f: "geojson",

                geometry: geometry,
                geometryType: "esriGeometry" + drawingMode,
                inSR: 4326,
                spatialRel: "esriSpatialRelIntersects",
                returnGeometry: true

            })

        }
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Call executeQuery using the drawn geometry when the user is finished drawing.

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        }

        function performQuery() {
            viewer.dataSources.removeAll();
            const geometry = getArcGISFeature(activeShapePoints);

            executeQuery(geometry);

            drawShape(activeShapePoints);
            terminateShape()
        }

        // Redraw the shape so it's not dynamic and remove the dynamic shape.
        function terminateShape() {
            viewer.entities.remove(floatingPoint);
            viewer.entities.remove(activeShape);
            floatingPoint = undefined;
            activeShape = undefined;
            activeShapePoints = [];
            newShape = true;
        }

        // Event listeners
        handler.setInputAction(function (event) {
            if (drawingMode === "Point" || !drawingMode) return;
            activeShapePoints.pop();

            performQuery();

        }, Cesium.ScreenSpaceEventType.LEFT_DOUBLE_CLICK);
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Load the resulting features onto the map as a Cesium.GeoJsonDataSource.

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        function executeQuery(geometry) {

            arcgisRest.queryFeatures({
                url: layerURL,
                authentication,
                f: "geojson",

                geometry: geometry,
                geometryType: "esriGeometry" + drawingMode,
                inSR: 4326,
                spatialRel: "esriSpatialRelIntersects",
                returnGeometry: true

            })

                .then((response) => {
                    Cesium.GeoJsonDataSource.load(response).then((data) => {
                        viewer.dataSources.add(data);
                    })
                })

        }
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Run the app

Run the app.

You should be able to draw features on the map and perform spatial queries against the feature layer.

What's next?

Learn how to use additional ArcGIS location services in these tutorials:

Query features (SQL)

Execute a SQL query to access polygon features from a feature service.

Style features

Use data-driven styling to apply symbol colors and styles to features.

Get global data

Query demographic information for locations around the world with the GeoEnrichment service.