Project-OSRM · DennisOSRM · May 3, 2026 · Feb 16, 2025 · May 3, 2026 · May 3, 2026
diff --git a/docker/entrypoint.sh b/docker/entrypoint.sh
@@ -58,6 +58,17 @@ cat > /usr/share/nginx/html/config.json << EOF
 }
 EOF
 
+# Inject OSRM_ENVIRONMENT into index.html meta tag to signal client to load config.json
+if [ -f /usr/share/nginx/html/index.html ]; then
+  TMPFILE=$(mktemp)
+  awk -v env="$OSRM_ENVIRONMENT" '{
+    if ($0 ~ /<meta name="osrm-environment"/) {
+      sub(/content="[^"]*"/, "content=\"" env "\"")
+    }
+    print
+  }' /usr/share/nginx/html/index.html > "$TMPFILE" && mv "$TMPFILE" /usr/share/nginx/html/index.html || true
+fi
+
 # Execute the default command (nginx) or any command passed to the container
 if [ "$#" -eq 0 ]; then
   exec nginx -g "daemon off;"

diff --git a/index.html b/index.html
@@ -8,6 +8,7 @@
     <link rel='stylesheet' href="css/leaflet.css" />
     <link rel="stylesheet" href="css/fonts.css" />
     <link href='css/site.css' rel='stylesheet' />
+    <meta name="osrm-environment" content="">
 
   </head>
   <body>
@@ -59,7 +60,13 @@
           });
         }
 
-        loadConfig().then(loadBundle);
+        var envMeta = document.querySelector('meta[name="osrm-environment"]');
+        if (envMeta && envMeta.content === 'docker') {
+          loadConfig().then(loadBundle);
+        } else {
+          // Not running in Docker — skip fetching config.json to avoid noisy 404s
+          loadBundle();
+        }
       })();
     </script>
   </body>

diff --git a/src/leaflet_options.js b/src/leaflet_options.js
@@ -228,9 +228,43 @@ function getZoom() {
   return parsedZoom;
 }
 
-// Get language from config
+// Get language, prefer browser settings when available; fallback to 'en'.
+// Precedence (effective): URL param (handled in index.js) > browser language > 'en'
 function getLanguage() {
-  return config.OSRM_LANGUAGE || 'en';
+  try {
+    if (typeof window !== 'undefined' && window.navigator) {
+      var nav = window.navigator;
+      var candidates = [];
+
+      if (Array.isArray(nav.languages)) {
+        candidates = candidates.concat(nav.languages);
+      }
+      if (nav.language) candidates.push(nav.language);
+      if (nav.userLanguage) candidates.push(nav.userLanguage); // IE fallback
+
+      var localization = require('./localization');
+      for (var i = 0; i < candidates.length; i++) {
+        var lang = candidates[i];
+        if (!lang) continue;
+        lang = lang.trim();
+        // exact match (e.g., 'pt-BR')
+        if (localization.get(lang)) {
+          return lang;
+        }
+        // primary subtag match (e.g., 'en-US' -> 'en')
+        var short = lang.split('-')[0];
+        if (localization.get(short)) {
+          return short;
+        }
+      }
+    }
+  } catch (e) {
+    // Ignore detection errors and fall back to default
+    console.warn('Error detecting browser language:', e);
+  }
+
+  // Fallback to English when no browser language matches
+  return 'en';
 }
 
 // Get default layer from config

diff --git a/test/leaflet_options.test.js b/test/leaflet_options.test.js
@@ -198,20 +198,52 @@ describe('leaflet_options — runtime configuration overrides', () => {
     });
   });
 
-  describe('OSRM_LANGUAGE override', () => {
-    test('uses custom language when provided', () => {
-      global.window = { osrmConfig: { OSRM_LANGUAGE: 'de' } };
+  describe('language precedence (URL > browser > en)', () => {
+    test('uses browser language exact match', () => {
+      global.window = { navigator: { languages: ['de'], language: 'de' } };
       const leafletOptions = require('../src/leaflet_options');
       expect(leafletOptions.defaultState.language).toBe('de');
       delete global.window;
     });
 
-    test('defaults to en when language not provided', () => {
-      global.window = { osrmConfig: {} };
+    test('uses primary subtag when regional locale provided (en-US -> en)', () => {
+      global.window = { navigator: { languages: ['en-US'], language: 'en-US' } };
+      const leafletOptions = require('../src/leaflet_options');
+      expect(leafletOptions.defaultState.language).toBe('en');
+      delete global.window;
+    });
+
+    test('prefers first candidate in navigator.languages array', () => {
+      global.window = { navigator: { languages: ['fr-CA', 'de'], language: 'fr-CA' } };
+      const leafletOptions = require('../src/leaflet_options');
+      expect(leafletOptions.defaultState.language).toBe('fr');
+      delete global.window;
+    });
+
+    test('matches exact regional variant when available (pt-BR)', () => {
+      global.window = { navigator: { languages: ['pt-BR'], language: 'pt-BR' } };
+      const leafletOptions = require('../src/leaflet_options');
+      expect(leafletOptions.defaultState.language).toBe('pt-BR');
+      delete global.window;
+    });
+
+    test('falls back to English when no supported browser languages', () => {
+      global.window = { navigator: { languages: ['xx','yy'], language: 'xx' } };
       const leafletOptions = require('../src/leaflet_options');
       expect(leafletOptions.defaultState.language).toBe('en');
       delete global.window;
     });
+
+    test('URL param (hl) takes precedence over browser default when merged', () => {
+      // Simulate browser default 'en' but URL param asks for 'de'
+      global.window = { navigator: { languages: ['en'], language: 'en' } };
+      const leafletOptions = require('../src/leaflet_options');
+      const links = require('../src/links');
+      const parsed = links.parse('hl=de');
+      const merged = Object.assign({}, leafletOptions.defaultState, parsed);
+      expect(merged.language).toBe('de');
+      delete global.window;
+    });
   });
 
   describe('OSRM_LABEL and OSRM_DEFAULT_LAYER overrides', () => {