xds: rename SecretProvider to SslContextProvider and make it non-gene…

…ric (#6349)

xds/src/main/java/io/grpc/xds/sds/SslContextSecretVolumeSecretProvider.java → xds/src/main/java/io/grpc/xds/sds/SecretVolumeSslContextProvider.java

@@ -45,18 +45,18 @@
  * An SslContext provider that uses file-based secrets (secret volume). Used for both server and
  * client SslContexts
  */
-final class SslContextSecretVolumeSecretProvider implements SecretProvider<SslContext> {
+final class SecretVolumeSslContextProvider implements SslContextProvider {
 
   private static final Logger logger =
-      Logger.getLogger(SslContextSecretVolumeSecretProvider.class.getName());
+      Logger.getLogger(SecretVolumeSslContextProvider.class.getName());
 
   private final boolean server;
   @Nullable private final String privateKey;
   @Nullable private final String privateKeyPassword;
   @Nullable private final String certificateChain;
   @Nullable private final CertificateValidationContext certContext;
 
-  private SslContextSecretVolumeSecretProvider(
+  private SecretVolumeSslContextProvider(
       @Nullable String privateKey,
       @Nullable String privateKeyPassword,
       @Nullable String certificateChain,
@@ -106,7 +106,7 @@ static TlsCertificate validateTlsCertificate(
     return tlsCertificate;
   }
 
-  static SslContextSecretVolumeSecretProvider getProviderForServer(
+  static SecretVolumeSslContextProvider getProviderForServer(
       DownstreamTlsContext downstreamTlsContext) {
     checkNotNull(downstreamTlsContext, "downstreamTlsContext");
     CommonTlsContext commonTlsContext = downstreamTlsContext.getCommonTlsContext();
@@ -125,15 +125,15 @@ static SslContextSecretVolumeSecretProvider getProviderForServer(
     }
     String privateKeyPassword =
         tlsCertificate.hasPassword() ? tlsCertificate.getPassword().getInlineString() : null;
-    return new SslContextSecretVolumeSecretProvider(
+    return new SecretVolumeSslContextProvider(
         tlsCertificate.getPrivateKey().getFilename(),
         privateKeyPassword,
         tlsCertificate.getCertificateChain().getFilename(),
         certificateValidationContext,
         /* server= */ true);
   }
 
-  static SslContextSecretVolumeSecretProvider getProviderForClient(
+  static SecretVolumeSslContextProvider getProviderForClient(
       UpstreamTlsContext upstreamTlsContext) {
     checkNotNull(upstreamTlsContext, "upstreamTlsContext");
     CommonTlsContext commonTlsContext = upstreamTlsContext.getCommonTlsContext();
@@ -159,7 +159,7 @@ static SslContextSecretVolumeSecretProvider getProviderForClient(
       }
       certificateChain = tlsCertificate.getCertificateChain().getFilename();
     }
-    return new SslContextSecretVolumeSecretProvider(
+    return new SecretVolumeSslContextProvider(
         privateKey,
         privateKeyPassword,
         certificateChain,
@@ -181,7 +181,7 @@ private static CertificateValidationContext getCertificateValidationContext(
   }
 
   @Override
-  public void addCallback(final Callback<SslContext> callback, Executor executor) {
+  public void addCallback(final Callback callback, Executor executor) {
     checkNotNull(callback, "callback");
     checkNotNull(executor, "executor");
     executor.execute(

xds/src/main/java/io/grpc/xds/sds/SecretProvider.java → xds/src/main/java/io/grpc/xds/sds/SslContextProvider.java

@@ -17,28 +17,30 @@
 package io.grpc.xds.sds;
 
 import io.grpc.Internal;
+import io.netty.handler.ssl.SslContext;
+
 import java.util.concurrent.Executor;
 
 /**
- * A SecretProvider is a "container" or provider of a secret. This is used by gRPC-xds to access
- * secrets, so is not part of the public API of gRPC. This "container" may represent a stream that
- * is receiving the requested secret(s) or it could represent file-system based secret(s) that are
- * dynamic.
+ * A SslContextProvider is a "container" or provider of SslContext. This is used by gRPC-xds to
+ * obtain an SslContext, so is not part of the public API of gRPC. This "container" may represent
+ * a stream that is receiving the requested secret(s) or it could represent file-system based
+ * secret(s) that are dynamic.
  */
 @Internal
-public interface SecretProvider<T> {
+public interface SslContextProvider {
 
-  interface Callback<T> {
-    /** Informs callee of new/updated secret. */
-    void updateSecret(T secret);
+  interface Callback {
+    /** Informs callee of new/updated SslContext. */
+    void updateSecret(SslContext sslContext);
 
     /** Informs callee of an exception that was generated. */
     void onException(Throwable throwable);
   }
 
   /**
-   * Registers a callback on the given executor. The callback will run when secret becomes available
-   * or immediately if the result is already available.
+   * Registers a callback on the given executor. The callback will run when SslContext becomes
+   * available or immediately if the result is already available.
    */
-  void addCallback(Callback<T> callback, Executor executor);
+  void addCallback(Callback callback, Executor executor);
 }

xds/src/main/java/io/grpc/xds/sds/TlsContextManager.java

@@ -19,13 +19,12 @@
 import io.envoyproxy.envoy.api.v2.auth.DownstreamTlsContext;
 import io.envoyproxy.envoy.api.v2.auth.UpstreamTlsContext;
 import io.grpc.Internal;
-import io.netty.handler.ssl.SslContext;
 
 /**
  * Class to manage secrets used to create SSL contexts - this effectively manages SSL contexts
  * (aka TlsContexts) based on inputs we get from xDS. This is used by gRPC-xds to access the
  * SSL contexts/secrets and is not public API.
- * Currently it just creates a new SecretProvider for each call.
+ * Currently it just creates a new SslContextProvider for each call.
  */
 // TODO(sanjaypujare): implement a Map and ref-counting
 @Internal
@@ -43,15 +42,15 @@ public static synchronized TlsContextManager getInstance() {
     return instance;
   }
 
-  /** Creates a SecretProvider. Used for retrieving a server-side SslContext. */
-  public SecretProvider<SslContext> findOrCreateServerSslContextProvider(
+  /** Creates a SslContextProvider. Used for retrieving a server-side SslContext. */
+  public SslContextProvider findOrCreateServerSslContextProvider(
       DownstreamTlsContext downstreamTlsContext) {
-    return SslContextSecretVolumeSecretProvider.getProviderForServer(downstreamTlsContext);
+    return SecretVolumeSslContextProvider.getProviderForServer(downstreamTlsContext);
   }
 
-  /** Creates a SecretProvider. Used for retrieving a client-side SslContext. */
-  public SecretProvider<SslContext> findOrCreateClientSslContextProvider(
+  /** Creates a SslContextProvider. Used for retrieving a client-side SslContext. */
+  public SslContextProvider findOrCreateClientSslContextProvider(
       UpstreamTlsContext upstreamTlsContext) {
-    return SslContextSecretVolumeSecretProvider.getProviderForClient(upstreamTlsContext);
+    return SecretVolumeSslContextProvider.getProviderForClient(upstreamTlsContext);
   }
 }

xds/src/main/java/io/grpc/xds/sds/internal/SdsProtocolNegotiators.java

@@ -29,7 +29,7 @@
 import io.grpc.netty.InternalProtocolNegotiator.ProtocolNegotiator;
 import io.grpc.netty.InternalProtocolNegotiators;
 import io.grpc.netty.NettyChannelBuilder;
-import io.grpc.xds.sds.SecretProvider;
+import io.grpc.xds.sds.SslContextProvider;
 import io.grpc.xds.sds.TlsContextManager;
 import io.netty.channel.ChannelHandler;
 import io.netty.channel.ChannelHandlerAdapter;
@@ -192,11 +192,11 @@ protected void handlerAdded0(final ChannelHandlerContext ctx) {
       final BufferReadsHandler bufferReads = new BufferReadsHandler();
       ctx.pipeline().addBefore(ctx.name(), null, bufferReads);
 
-      SecretProvider<SslContext> sslContextProvider =
+      SslContextProvider sslContextProvider =
           TlsContextManager.getInstance().findOrCreateClientSslContextProvider(upstreamTlsContext);
 
       sslContextProvider.addCallback(
-          new SecretProvider.Callback<SslContext>() {
+          new SslContextProvider.Callback() {
 
             @Override
             public void updateSecret(SslContext sslContext) {
@@ -277,12 +277,12 @@ protected void handlerAdded0(final ChannelHandlerContext ctx) {
       final BufferReadsHandler bufferReads = new BufferReadsHandler();
       ctx.pipeline().addBefore(ctx.name(), null, bufferReads);
 
-      SecretProvider<SslContext> sslContextProvider =
+      SslContextProvider sslContextProvider =
           TlsContextManager.getInstance()
               .findOrCreateServerSslContextProvider(downstreamTlsContext);
 
       sslContextProvider.addCallback(
-          new SecretProvider.Callback<SslContext>() {
+          new SslContextProvider.Callback() {
 
             @Override
             public void updateSecret(SslContext sslContext) {