Learn how to query global demographic information and display it on a map.
The ArcGIS GeoEnrichment service provides global demographic data for 170 countries and regions. To get globally available information, you use the Key data collection, which returns information for the total population, total households, average household size, and total population for males and females for a study area.
In this tutorial, use the MapLibre ArcGIS plugin to display a map and ArcGIS REST JS to access the GeoEnrichment service and display global data for Eastern Europe.
Prerequisites
You need an ArcGIS Location Platform or ArcGIS Online account.
Steps
Get the starter app
Select a type of authentication and follow the steps to create a new app.
Choose API key authentication if you:
- Want the easiest way to get started.
- Want to build public applications that access ArcGIS Location Services and secure items.
- Have an ArcGIS Location Platform or ArcGIS Online account.
Choose user authentication if you:
- Want to build private applications.
- Require application users to sign in with their own ArcGIS account and access resources their behalf.
- Have an ArcGIS Online account.
To learn more about both types of authentication, go to Authentication.
Set up authentication
Set developer credentials
Use the API key or OAuth developer credentials so your application can access ArcGIS services.
Add references to ArcGIS REST JS
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Reference the
requestanddemographicsmodules from ArcGIS REST JS.Use dark colors for code blocks <head> <title>MapLibre ArcGIS tutorial: Query demographic data</title> <meta charset="utf-8"> <meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no"> <!-- Load MapLibre GL JS from CDN --> <script src="https://unpkg.com/maplibre-gl@5.23.0/dist/maplibre-gl.js"></script> <link href="https://unpkg.com/maplibre-gl@5.23.0/dist/maplibre-gl.css" rel="stylesheet"> <!-- Load MapLibre ArcGIS from CDN --> <script src="https://unpkg.com/@esri/maplibre-arcgis@1.1.0/dist/umd/maplibre-arcgis.min.js"></script> <script src="https://unpkg.com/@esri/arcgis-rest-request@4/dist/bundled/request.umd.js"></script> <script src="https://unpkg.com/@esri/arcgis-rest-demographics@4/dist/bundled/demographics.umd.js"></script> <style> html, body, #map { padding: 0; margin: 0; height: 100%; width: 100%; font-family: Arial, Helvetica, sans-serif; font-size: 14px; color: #323232; } </style> </head>
Update the map position
The GeoEnrichment service has data sources for many countries around the world, including most of Europe. Change the position of the map to center on eastern Europe.
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Update the
centerparameter to[18.88, 47.33]and setzoomto 5.Use dark colors for code blocks Copy /* 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; const map = new maplibregl.Map({ container: "map", // the id of the div element zoom: 5, // starting zoom center: [18.88, 47.33] // starting location [longitude, latitude] }); const basemapStyle = maplibreArcGIS.BasemapStyle.applyStyle(map, { style: "arcgis/outdoor", token: accessToken });
Add a click event handler
You need a location before calling the GeoEnrichment service. To get a location, you can add a handler to the Map's click event. The click handler will be called with an object containing a Lng.
You can change the mouse cursor to a crosshair to make it easier to click precisely. Use map.get to get the canvas, then modify its style property.
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After the map initialization code, set the mouse cursor style to
crosshair.Use dark colors for code blocks const map = new maplibregl.Map({ container: "map", // the id of the div element zoom: 5, // starting zoom center: [18.88, 47.33] // starting location [longitude, latitude] }); const basemapStyle = maplibreArcGIS.BasemapStyle.applyStyle(map, { style: "arcgis/outdoor", token: accessToken }); map.getCanvas().style.cursor = "crosshair"; -
Add an
asynchandler for theclickevent.Use dark colors for code blocks map.getCanvas().style.cursor = "crosshair"; map.on("click", async (e) => { // e.lngLat contains the clicked location });
Execute the query
You pass one or more study areas to query to specify the location of your query. To query a buffer around a point, pass a geometry object with x and y parameters. The default search radius is one mile.
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Create a new authentication object from your access token.
Use dark colors for code blocks const map = new maplibregl.Map({ container: "map", // the id of the div element zoom: 5, // starting zoom center: [18.88, 47.33] // starting location [longitude, latitude] }); const basemapStyle = maplibreArcGIS.BasemapStyle.applyStyle(map, { style: "arcgis/outdoor", token: accessToken }); const authentication = arcgisRest.ApiKeyManager.fromKey(accessToken); -
Inside the click handler, call
query. Set theDemographic Data studyparameter to a point geometry made from the event'sAreas lngproperty. Set theLat dataparameter to toCollections ["to obtain global data.Key Global Facts"] queryis an asynchronous function. UsingDemographic Data await, and declaring the click handlerasync, means the rest of the click handler will wait for a response from the GeoEnrichment service before continuing.Use dark colors for code blocks map.on("click", async (e) => { // e.lngLat contains the clicked location const response = await arcgisRest.queryDemographicData({ studyAreas: [ { geometry: { x: e.lngLat.lng, y: e.lngLat.lat } } ], dataCollections: ["KeyGlobalFacts"], authentication: authentication }); });
Show a pop-up
If the query is successful, the response will contain a results array with a value containing a Feature. The Feature contains attributes such as population within the study area, the number of males and females, and the average household size. A message will display if there is no data available for a location selected.
You can use a pop-up to show the results of the query at the location where you clicked on the map.
To add a pop-up to the map, you use the Popup class in MapLibre GL JS. See the Display a pop-up tutorial for more information.
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Set a variable containing the contents of the pop-up, using values from the query response.
Use dark colors for code blocks const response = await arcgisRest.queryDemographicData({ studyAreas: [ { geometry: { x: e.lngLat.lng, y: e.lngLat.lat } } ], dataCollections: ["KeyGlobalFacts"], authentication: authentication }); let message; const featureSet = response.results[0].value.FeatureSet; if (featureSet.length > 0 && featureSet[0].features.length > 0) { const attributes = featureSet[0].features[0].attributes; message = "<b>Data for a 1 mile search radius</b><br>" + [ `Population: ${attributes.TOTPOP.toLocaleString()}`, `Males: ${attributes.TOTMALES.toLocaleString()}`, `Females: ${attributes.TOTFEMALES.toLocaleString()}`, `Average household size: ${attributes.AVGHHSZ}` ].join("<br>"); } else { message = "Data not available for this location."; } -
Create a
Popupto display amessagecontaining demographic attributes, and add it to the map at the clicked location.Use dark colors for code blocks } else { message = "Data not available for this location."; } return new maplibregl.Popup().setHTML(message).setLngLat(e.lngLat).addTo(map);
Run the app
Run the app.
You should now see a map centered over eastern Europe. Click on the map to query for demographic data and view the results in a popup.What's next?
Learn how to use additional location services in these tutorials:
