chore(spanner): deprecate experimental host option/parameter to replace with Spanner Omni

java-spanner/google-cloud-spanner/clirr-ignored-differences.xml

@@ -910,21 +910,21 @@
     <method>java.lang.Object runTransaction(com.google.cloud.spanner.connection.Connection$TransactionCallable)</method>
   </difference>
 
-  <!-- Added experimental host option -->
+  <!-- Added Spanner Omni option -->
   <difference>
     <differenceType>7012</differenceType>
     <className>com/google/cloud/spanner/SpannerOptions$SpannerEnvironment</className>
-    <method>com.google.auth.oauth2.GoogleCredentials getDefaultExperimentalHostCredentials()</method>
+    <method>com.google.auth.oauth2.GoogleCredentials getDefaultSpannerOmniCredentials()</method>
   </difference>
   <difference>
     <differenceType>7002</differenceType>
     <className>com/google/cloud/spanner/SpannerOptions$SpannerEnvironment</className>
-    <method>com.google.auth.oauth2.GoogleCredentials getDefaultExternalHostCredentials()</method>
+    <method>com.google.auth.oauth2.GoogleCredentials getDefaultSpannerOmniCredentials()</method>
   </difference>
   <difference>
     <differenceType>7002</differenceType>
     <className>com/google/cloud/spanner/SpannerOptions</className>
-    <method>com.google.auth.oauth2.GoogleCredentials getDefaultExternalHostCredentialsFromSysEnv()</method>
+    <method>com.google.auth.oauth2.GoogleCredentials getDefaultSpannerOmniCredentialsFromSysEnv()</method>
   </difference>
 
   <!-- Default sequence kind -->

java-spanner/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SpannerOptions.java

@@ -126,7 +126,8 @@ public class SpannerOptions extends ServiceOptions<Spanner, SpannerOptions> {
   private static final String API_SHORT_NAME = "Spanner";
   private static final String SPANNER_SERVICE_NAME = "spanner";
   private static final String GOOGLE_DEFAULT_UNIVERSE = "googleapis.com";
-  private static final String EXPERIMENTAL_HOST_PROJECT_ID = "default";
+  public static final String SPANNER_OMNI_PROJECT_ID = "default";
+  public static final String DEFAULT_SPANNER_OMNI_INSTANCE_ID = "default";
 
   static final ImmutableSet<String> SCOPES =
       ImmutableSet.of(
@@ -314,6 +315,18 @@ enum TracingFramework {
     OPEN_TELEMETRY
   }
 
+  /**
+   * Specifies the type of Spanner instance to connect to (CLOUD, OMNI, or EMULATOR). Currently,
+   * this is a no-op for most types, but setting it to OMNI is mandatory when connecting to a
+   * Spanner Omni instance.
+   */
+  public enum InstanceType {
+    UNSPECIFIED,
+    CLOUD,
+    OMNI,
+    EMULATOR
+  }
+
   private static final Object lock = new Object();
 
   @GuardedBy("lock")
@@ -874,7 +887,9 @@ protected SpannerOptions(Builder builder) {
         "Number of channels must fall in the range [1, %s], found: %s",
         MAX_CHANNELS,
         numChannels);
-
+    Preconditions.checkArgument(
+        builder.instanceType != InstanceType.OMNI || !Strings.isNullOrEmpty(builder.host),
+        "Host must be set for connecting to Spanner Omni instances");
     transportChannelExecutorThreadNameFormat = builder.transportChannelExecutorThreadNameFormat;
     channelProvider = builder.channelProvider;
     channelEndpointCacheFactory = builder.channelEndpointCacheFactory;
@@ -924,16 +939,17 @@ protected SpannerOptions(Builder builder) {
 
     // Dynamic channel pooling is disabled by default.
     // It is only enabled when:
-    // 1. enableDynamicChannelPool() was explicitly called (or experimentalHost is set and DCP was
+    // 1. enableDynamicChannelPool() was explicitly called (or instance is set to OMNI and DCP was
     //    not explicitly disabled), AND
     // 2. grpc-gcp extension is enabled, AND
     // 3. numChannels was not explicitly set
     boolean dcpRequested =
         builder.dynamicChannelPoolEnabled != null
             ? builder.dynamicChannelPoolEnabled
-            : builder.experimentalHost != null;
+            : builder.instanceType == InstanceType.OMNI;
     if (dcpRequested) {
-      // DCP was enabled (explicitly or via experimentalHost), but respect numChannels if set
+      // DCP was enabled (explicitly or via instance type being OMNI), but respect numChannels if
+      // set
       dynamicChannelPoolEnabled = grpcGcpExtensionEnabled && !builder.numChannelsExplicitlySet;
     } else {
       // DCP is disabled by default, or was explicitly disabled
@@ -976,14 +992,14 @@ protected SpannerOptions(Builder builder) {
     openTelemetry = builder.openTelemetry;
     enableApiTracing = builder.enableApiTracing;
     enableExtendedTracing = builder.enableExtendedTracing;
-    if (builder.experimentalHost != null) {
+    if (builder.instanceType == InstanceType.OMNI) {
       enableBuiltInMetrics = false;
     } else {
       enableBuiltInMetrics = builder.enableBuiltInMetrics;
     }
-    // Enable location API when experimental host is set, unless explicitly disabled
+    // Enable location API when InstanceType is OMNI, unless explicitly disabled
     // via GOOGLE_SPANNER_EXPERIMENTAL_LOCATION_API=false.
-    if (builder.experimentalHost != null) {
+    if (builder.instanceType == InstanceType.OMNI) {
       String locationApiEnvValue = System.getenv(EXPERIMENTAL_LOCATION_API_ENV_VAR);
       enableLocationApi = locationApiEnvValue == null || Boolean.parseBoolean(locationApiEnvValue);
     } else {
@@ -1072,13 +1088,12 @@ default String getMonitoringHost() {
       return null;
     }
 
-    default GoogleCredentials getDefaultExperimentalHostCredentials() {
+    default GoogleCredentials getDefaultSpannerOmniCredentials() {
       return null;
     }
   }
 
-  static final String DEFAULT_SPANNER_EXPERIMENTAL_HOST_CREDENTIALS =
-      "SPANNER_EXPERIMENTAL_HOST_AUTH_TOKEN";
+  static final String DEFAULT_SPANNER_OMNI_CREDENTIALS = "SPANNER_OMNI_AUTH_TOKEN";
 
   /**
    * Default implementation of {@link SpannerEnvironment}. Reads all configuration from environment
@@ -1174,8 +1189,8 @@ public String getMonitoringHost() {
     }
 
     @Override
-    public GoogleCredentials getDefaultExperimentalHostCredentials() {
-      return getOAuthTokenFromFile(System.getenv(DEFAULT_SPANNER_EXPERIMENTAL_HOST_CREDENTIALS));
+    public GoogleCredentials getDefaultSpannerOmniCredentials() {
+      return getOAuthTokenFromFile(System.getenv(DEFAULT_SPANNER_OMNI_CREDENTIALS));
     }
   }
 
@@ -1252,10 +1267,11 @@ public static class Builder
     private boolean enableLocationApi = SpannerOptions.environment.isEnableLocationApi();
     private String monitoringHost = SpannerOptions.environment.getMonitoringHost();
     private SslContext mTLSContext = null;
-    private String experimentalHost = null;
     private boolean usePlainText = false;
     private TransactionOptions defaultTransactionOptions = TransactionOptions.getDefaultInstance();
     private RequestOptions.ClientContext clientContext;
+    private InstanceType instanceType = InstanceType.UNSPECIFIED;
+    private String host = null;
 
     private static String createCustomClientLibToken(String token) {
       return token + " " + ServiceOptions.getGoogApiClientLibName();
@@ -1794,27 +1810,48 @@ public Builder setDecodeMode(DecodeMode decodeMode) {
 
     @Override
     public Builder setHost(String host) {
-      super.setHost(host);
+      this.host = host;
+      if (this.instanceType == InstanceType.OMNI
+          && !Strings.isNullOrEmpty(this.host)
+          && this.usePlainText) {
+        Preconditions.checkArgument(
+            !this.host.startsWith("https:"),
+            "Please remove the 'https:' protocol prefix from the host string when using plain text"
+                + " communication");
+        if (!this.host.startsWith("http")) {
+          this.host = "http://" + this.host;
+        }
+      }
+      super.setHost(this.host);
       // Setting a host should override any SPANNER_EMULATOR_HOST setting.
       setEmulatorHost(null);
       return this;
     }
 
+    /** @deprecated Use {@link #setType(InstanceType)} instead. */
+    @Deprecated
+    @ObsoleteApi("Use setHost(String).setType(InstanceType.OMNI) instead")
     @ExperimentalApi("https://github.com/googleapis/java-spanner/pull/3676")
     public Builder setExperimentalHost(String host) {
-      if (this.usePlainText) {
-        Preconditions.checkArgument(
-            !host.startsWith("https:"),
-            "Please remove the 'https:' protocol prefix from the host string when using plain text"
-                + " communication");
-        if (!host.startsWith("http")) {
-          host = "http://" + host;
-        }
+      if (!Strings.isNullOrEmpty(host)) {
+        setType(InstanceType.OMNI);
+      }
+      setHost(host);
+      return this;
+    }
+
+    /**
+     * Specifies the type of Spanner instance to connect to (CLOUD, OMNI, or EMULATOR). Currently,
+     * this is a no-op for most types, but setting it to OMNI is mandatory when connecting to a
+     * Spanner Omni instance.
+     */
+    public Builder setType(InstanceType instanceType) {
+      this.instanceType = instanceType;
+      if (instanceType == InstanceType.OMNI) {
+        setBuiltInMetricsEnabled(false);
+        super.setProjectId(SPANNER_OMNI_PROJECT_ID);
+        setSessionPoolOption(SessionPoolOptions.newBuilder().setExperimentalHost().build());
       }
-      super.setHost(host);
-      super.setProjectId(EXPERIMENTAL_HOST_PROJECT_ID);
-      setSessionPoolOption(SessionPoolOptions.newBuilder().setExperimentalHost().build());
-      this.experimentalHost = host;
       return this;
     }
 
@@ -1916,14 +1953,13 @@ public Builder setEmulatorHost(String emulatorHost) {
     }
 
     /**
-     * Configures mTLS authentication using the provided client certificate and key files. mTLS is
-     * only supported for experimental spanner hosts.
+     * Configures mTLS authentication using the provided client certificate and key files. mTLS via
+     * useClientCert is only supported for Spanner Omni instances.
      *
      * @param clientCertificate Path to the client certificate file.
      * @param clientCertificateKey Path to the client private key file.
      * @throws SpannerException If an error occurs while configuring the mTLS context
      */
-    @ExperimentalApi("https://github.com/googleapis/java-spanner/pull/3574")
     public Builder useClientCert(String clientCertificate, String clientCertificateKey) {
       try {
         this.mTLSContext =
@@ -1941,14 +1977,13 @@ public Builder useClientCert(String clientCertificate, String clientCertificateK
      * credentials to {@link com.google.cloud.NoCredentials} to avoid sending authentication over an
      * unsecured channel.
      */
-    @ExperimentalApi("https://github.com/googleapis/java-spanner/pull/4264")
     public Builder usePlainText() {
       this.usePlainText = true;
       this.setChannelConfigurator(ManagedChannelBuilder::usePlaintext)
           .setCredentials(NoCredentials.getInstance());
-      if (this.experimentalHost != null) {
+      if (this.instanceType == InstanceType.OMNI) {
         // Re-apply host settings to ensure http:// is prepended.
-        setExperimentalHost(this.experimentalHost);
+        setHost(this.host);
       }
       return this;
     }
@@ -2124,7 +2159,7 @@ public Builder setDefaultClientContext(RequestOptions.ClientContext clientContex
     @Override
     public SpannerOptions build() {
       // Set the host of emulator has been set.
-      if (emulatorHost != null && experimentalHost == null) {
+      if (emulatorHost != null && this.instanceType != InstanceType.OMNI) {
         if (!emulatorHost.startsWith("http")) {
           emulatorHost = "http://" + emulatorHost;
         }
@@ -2134,8 +2169,8 @@ public SpannerOptions build() {
         this.setChannelConfigurator(ManagedChannelBuilder::usePlaintext);
         // As we are using plain text, we should never send any credentials.
         this.setCredentials(NoCredentials.getInstance());
-      } else if (experimentalHost != null && credentials == null) {
-        credentials = environment.getDefaultExperimentalHostCredentials();
+      } else if (this.instanceType == InstanceType.OMNI && credentials == null) {
+        credentials = environment.getDefaultSpannerOmniCredentials();
       }
       if (this.numChannels == null) {
         this.numChannels =
@@ -2177,8 +2212,8 @@ public static void useDefaultEnvironment() {
   }
 
   @InternalApi
-  public static GoogleCredentials getDefaultExperimentalCredentialsFromSysEnv() {
-    return getOAuthTokenFromFile(System.getenv(DEFAULT_SPANNER_EXPERIMENTAL_HOST_CREDENTIALS));
+  public static GoogleCredentials getDefaultSpannerOmniCredentialsFromSysEnv() {
+    return getOAuthTokenFromFile(System.getenv(DEFAULT_SPANNER_OMNI_CREDENTIALS));
   }
 
   private static @Nullable GoogleCredentials getOAuthTokenFromFile(@Nullable String file) {

java-spanner/google-cloud-spanner/src/main/java/com/google/cloud/spanner/connection/ClientSideStatementValueConverters.java

@@ -26,6 +26,7 @@
 import com.google.cloud.spanner.Options.RpcPriority;
 import com.google.cloud.spanner.SpannerException;
 import com.google.cloud.spanner.SpannerExceptionFactory;
+import com.google.cloud.spanner.SpannerOptions;
 import com.google.cloud.spanner.TimestampBound;
 import com.google.cloud.spanner.TimestampBound.Mode;
 import com.google.cloud.spanner.connection.PgTransactionMode.AccessMode;
@@ -895,4 +896,31 @@ public Dialect convert(String value) {
       return values.get(value);
     }
   }
+
+  static class InstanceTypeConverter
+      implements ClientSideStatementValueConverter<SpannerOptions.InstanceType> {
+    static final InstanceTypeConverter INSTANCE = new InstanceTypeConverter();
+
+    private final CaseInsensitiveEnumMap<SpannerOptions.InstanceType> values =
+        new CaseInsensitiveEnumMap<>(SpannerOptions.InstanceType.class);
+
+    private InstanceTypeConverter() {}
+
+    /** Constructor needed for reflection. */
+    public InstanceTypeConverter(String allowedValues) {}
+
+    @Override
+    public Class<SpannerOptions.InstanceType> getParameterClass() {
+      return SpannerOptions.InstanceType.class;
+    }
+
+    @Override
+    public SpannerOptions.InstanceType convert(String value) {
+      SpannerOptions.InstanceType converted = values.get(value);
+      if (converted == SpannerOptions.InstanceType.UNSPECIFIED) {
+        return null;
+      }
+      return converted;
+    }
+  }
 }