[BEAM-11805] Fix spanner test issues

sdks/java/io/google-cloud-platform/src/main/java/org/apache/beam/sdk/io/gcp/spanner/SpannerAccessor.java

@@ -41,6 +41,8 @@
 import io.grpc.ClientCall;
 import io.grpc.ClientInterceptor;
 import io.grpc.MethodDescriptor;
+import java.net.MalformedURLException;
+import java.net.URL;
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
@@ -187,7 +189,7 @@ private static SpannerAccessor createAndConnect(SpannerConfig spannerConfig) {
     ValueProvider<String> host = spannerConfig.getHost();
     if (host != null) {
       builder.setHost(host.get());
-      instantiatingGrpcChannelProvider.setEndpoint(host.get());
+      instantiatingGrpcChannelProvider.setEndpoint(getEndpoint(host.get()));
     }
     ValueProvider<String> emulatorHost = spannerConfig.getEmulatorHost();
     if (emulatorHost != null) {
@@ -199,7 +201,7 @@ private static SpannerAccessor createAndConnect(SpannerConfig spannerConfig) {
        * InstantiatingGrpcChannelProvider will override the settings provided.
        * The section below and all associated artifacts will be removed once the bug
        * that prevents setting user-agent is fixed.
-       * https://github.com/googleapis/java-spanner/pull/747
+       * https://github.com/googleapis/java-spanner/pull/871
        *
        * Code to be replaced:
        * builder.setHeaderProvider(FixedHeaderProvider.create("user-agent", userAgentString));
@@ -230,6 +232,17 @@ public Map<String, String> getHeaders() {
         spanner, databaseClient, databaseAdminClient, batchClient, spannerConfig);
   }
 
+  private static String getEndpoint(String host) {
+    URL url;
+    try {
+      url = new URL(host);
+    } catch (MalformedURLException e) {
+      throw new IllegalArgumentException("Invalid host: " + host, e);
+    }
+    return String.format(
+        "%s:%s", url.getHost(), url.getPort() < 0 ? url.getDefaultPort() : url.getPort());
+  }
+
   public DatabaseClient getDatabaseClient() {
     return databaseClient;
   }