This example uses OpenLayers v10.9.0. The latest is v.
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#### OSM XML

vector 86 osmxml 1 loading 8 server 5 strategy 2 bbox 5 maptiler 26

#####

Example of using the OSM XML source.

OSM XML vector data is loaded dynamically from a the Overpass API using a bbox strategy. Note that panning and zooming will eventually lead to "Too many requests" errors from the Overpass API.

##### main.js

    import Map from 'ol/Map.js';
    import View from 'ol/View.js';
    import OSMXML from 'ol/format/OSMXML.js';
    import TileLayer from 'ol/layer/Tile.js';
    import VectorLayer from 'ol/layer/Vector.js';
    import {bbox as bboxStrategy} from 'ol/loadingstrategy.js';
    import {transformExtent} from 'ol/proj.js';
    import ImageTile from 'ol/source/ImageTile.js';
    import VectorSource from 'ol/source/Vector.js';
    import CircleStyle from 'ol/style/Circle.js';
    import Fill from 'ol/style/Fill.js';
    import Stroke from 'ol/style/Stroke.js';
    import Style from 'ol/style/Style.js';

    let map = null;

    const styles = {
      'amenity': {
        'parking': new Style({
          stroke: new Stroke({
            color: 'rgba(170, 170, 170, 1.0)',
            width: 1,
          }),
          fill: new Fill({
            color: 'rgba(170, 170, 170, 0.3)',
          }),
        }),
      },
      'building': {
        '.*': new Style({
          zIndex: 100,
          stroke: new Stroke({
            color: 'rgba(246, 99, 79, 1.0)',
            width: 1,
          }),
          fill: new Fill({
            color: 'rgba(246, 99, 79, 0.3)',
          }),
        }),
      },
      'highway': {
        'service': new Style({
          stroke: new Stroke({
            color: 'rgba(255, 255, 255, 1.0)',
            width: 2,
          }),
        }),
        '.*': new Style({
          stroke: new Stroke({
            color: 'rgba(255, 255, 255, 1.0)',
            width: 3,
          }),
        }),
      },
      'landuse': {
        'forest|grass|allotments': new Style({
          stroke: new Stroke({
            color: 'rgba(140, 208, 95, 1.0)',
            width: 1,
          }),
          fill: new Fill({
            color: 'rgba(140, 208, 95, 0.3)',
          }),
        }),
      },
      'natural': {
        'tree': new Style({
          image: new CircleStyle({
            radius: 2,
            fill: new Fill({
              color: 'rgba(140, 208, 95, 1.0)',
            }),
            stroke: null,
          }),
        }),
      },
    };

    const vectorSource = new VectorSource({
      format: new OSMXML(),
      loader: function (extent, resolution, projection, success, failure) {
        const epsg4326Extent = transformExtent(extent, projection, 'EPSG:4326');
        const client = new XMLHttpRequest();
        client.open('POST', 'https://overpass-api.de/api/interpreter');
        client.addEventListener('load', function () {
          const features = new OSMXML().readFeatures(client.responseText, {
            featureProjection: map.getView().getProjection(),
          });
          vectorSource.addFeatures(features);
          success(features);
        });
        client.addEventListener('error', failure);
        const query =
          '(node(' +
          epsg4326Extent[1] +
          ',' +
          Math.max(epsg4326Extent[0], -180) +
          ',' +
          epsg4326Extent[3] +
          ',' +
          Math.min(epsg4326Extent[2], 180) +
          ');rel(bn)->.foo;way(bn);node(w)->.foo;rel(bw););out meta;';
        client.send(query);
      },
      strategy: bboxStrategy,
    });

    const vector = new VectorLayer({
      source: vectorSource,
      style: function (feature) {
        for (const key in styles) {
          const value = feature.get(key);
          if (value !== undefined) {
            for (const regexp in styles[key]) {
              if (new RegExp(regexp).test(value)) {
                return styles[key][regexp];
              }
            }
          }
        }
        return null;
      },
    });

    const key = 'Get your own API key at https://www.maptiler.com/cloud/';
    const attributions =
      '<a href="https://www.maptiler.com/copyright/" target="_blank">&copy; MapTiler</a> ' +
      '<a href="https://www.openstreetmap.org/copyright" target="_blank">&copy; OpenStreetMap contributors</a>';

    const raster = new TileLayer({
      source: new ImageTile({
        attributions: attributions,
        url: 'https://api.maptiler.com/maps/satellite/{z}/{x}/{y}.jpg?key=' + key,
        tileSize: 512,
        maxZoom: 20,
      }),
    });

    map = new Map({
      layers: [raster, vector],
      target: document.getElementById('map'),
      view: new View({
        center: [739218, 5906096],
        maxZoom: 19,
        zoom: 17,
      }),
    });

##### index.html

    <!DOCTYPE html>
    <html lang="en">
      <head>
        <meta charset="UTF-8">
        <title>OSM XML</title>
        <link rel="stylesheet" href="node_modules/ol/ol.css">
        <style>
          .map {
            width: 100%;
            height: 400px;
          }
        </style>
      </head>
      <body>
        <div id="map" class="map"></div>

        <script type="module" src="main.js"></script>
      </body>
    </html>

##### package.json

    {
      "name": "vector-osm",
      "dependencies": {
        "ol": "10.9.0"
      },
      "devDependencies": {
        "vite": "^3.2.3"
      },
      "scripts": {
        "start": "vite",
        "build": "vite build"
      }
    }