Format console times when a request has no Accept-Language

src/integration/java/org/jlab/epics2web/ConsoleTest.java

@@ -0,0 +1,62 @@
+package org.jlab.epics2web;
+
+import static org.junit.Assert.assertTrue;
+
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.net.http.WebSocket;
+import java.util.regex.Pattern;
+import org.junit.Test;
+
+/** Tests the /console page. */
+public class ConsoleTest {
+
+  private static final HttpClient HTTP = HttpClient.newHttpClient();
+
+  /**
+   * A request without Accept-Language, such as from a script, gets the console's time format, not
+   * Date.toString(), which JSTL falls back to when it finds no locale. HttpClient sends no
+   * Accept-Language.
+   */
+  @Test
+  public void timesAreFormattedWithoutAcceptLanguage() throws Exception {
+    WebSocket socket =
+        HTTP.newWebSocketBuilder()
+            .buildAsync(
+                URI.create("ws://localhost:8080/epics2web/monitor?clientName=console-test"),
+                new WebSocket.Listener() {})
+            .join();
+
+    try {
+      socket.sendText("{\"type\": \"monitor\", \"pvs\": [\"channel1\"]}", true).join();
+
+      // Monitor row cells: PV, state, last update ("MMM dd yyyy HH:mm:ss - value")
+      Pattern formatted =
+          Pattern.compile(
+              "<td>channel1</td>\\s*<td>[^<]*</td>\\s*<td>[A-Z][a-z]{2} \\d{2} \\d{4}"
+                  + " \\d{2}:\\d{2}:\\d{2} - ");
+
+      long deadline = System.currentTimeMillis() + 5_000;
+      boolean found = false;
+
+      while (!found && System.currentTimeMillis() < deadline) {
+        found = formatted.matcher(get("console").body()).find();
+        if (!found) {
+          Thread.sleep(100);
+        }
+      }
+
+      assertTrue("channel1's last update not formatted on the console", found);
+    } finally {
+      socket.abort();
+    }
+  }
+
+  private static HttpResponse<String> get(String path) throws Exception {
+    return HTTP.send(
+        HttpRequest.newBuilder().uri(URI.create("http://localhost:8080/epics2web/" + path)).build(),
+        HttpResponse.BodyHandlers.ofString());
+  }
+}

src/main/webapp/WEB-INF/web.xml

@@ -20,6 +20,11 @@
         <env-entry-type>java.lang.String</env-entry-type>
         <env-entry-value>@PRODUCTION_RELEASE@</env-entry-value>
     </env-entry> 
+    <context-param>
+        <param-name>jakarta.servlet.jsp.jstl.fmt.fallbackLocale</param-name>
+        <param-value>en-US</param-value>
+        <description>Locale of fmt tags when a request has no Accept-Language; without it they fall back to toString()</description>
+    </context-param>
     <context-param>
         <param-name>org.apache.tomcat.websocket.textBufferSize</param-name>
         <param-value>8192</param-value>