Merge pull request #6481 from dgquintas/compression_md_level_bis

Allow servers to select compression level via initial MD & overall compression cleanup

5 files changed, 76 insertions, 20 deletions

diff --git a/include/grpc++/impl/codegen/call.h b/include/grpc++/impl/codegen/call.h
index 4f550b42a2..d720f27a8f 100644
--- a/include/grpc++/impl/codegen/call.h
+++ b/include/grpc++/impl/codegen/call.h
@@ -47,7 +47,9 @@
 #include <grpc++/impl/codegen/serialization_traits.h>
 #include <grpc++/impl/codegen/status.h>
 #include <grpc++/impl/codegen/string_ref.h>
+
 #include <grpc/impl/codegen/alloc.h>
+#include <grpc/impl/codegen/compression_types.h>
 #include <grpc/impl/codegen/grpc_types.h>
 
 struct grpc_byte_buffer;
@@ -187,6 +189,8 @@ class CallOpSendInitialMetadata {
     flags_ = flags;
     initial_metadata_count_ = metadata.size();
     initial_metadata_ = FillMetadataArray(metadata);
+    // TODO(dgq): expose compression level in API so it can be properly set.
+    maybe_compression_level_.is_set = false;
   }
 
  protected:
@@ -198,6 +202,10 @@ class CallOpSendInitialMetadata {
     op->reserved = NULL;
     op->data.send_initial_metadata.count = initial_metadata_count_;
     op->data.send_initial_metadata.metadata = initial_metadata_;
+    op->data.send_initial_metadata.maybe_compression_level.is_set =
+        maybe_compression_level_.is_set;
+    op->data.send_initial_metadata.maybe_compression_level.level =
+        maybe_compression_level_.level;
   }
   void FinishOp(bool* status, int max_message_size) {
     if (!send_) return;
@@ -209,6 +217,10 @@ class CallOpSendInitialMetadata {
   uint32_t flags_;
   size_t initial_metadata_count_;
   grpc_metadata* initial_metadata_;
+  struct {
+    bool is_set;
+    grpc_compression_level level;
+  } maybe_compression_level_;
 };
 
 class CallOpSendMessage {
diff --git a/include/grpc++/server_builder.h b/include/grpc++/server_builder.h
index 8525cb70cb..54f01d11b5 100644
--- a/include/grpc++/server_builder.h
+++ b/include/grpc++/server_builder.h
@@ -66,29 +66,43 @@ class ServerBuilder {
   /// The service must exist for the lifetime of the \a Server instance returned
   /// by \a BuildAndStart().
   /// Matches requests with any :authority
-  void RegisterService(Service* service);
+  ServerBuilder& RegisterService(Service* service);
 
   /// Register a generic service.
   /// Matches requests with any :authority
-  void RegisterAsyncGenericService(AsyncGenericService* service);
+  ServerBuilder& RegisterAsyncGenericService(AsyncGenericService* service);
 
   /// Register a service. This call does not take ownership of the service.
   /// The service must exist for the lifetime of the \a Server instance returned
   /// by BuildAndStart().
   /// Only matches requests with :authority \a host
-  void RegisterService(const grpc::string& host, Service* service);
+  ServerBuilder& RegisterService(const grpc::string& host, Service* service);
 
   /// Set max message size in bytes.
-  void SetMaxMessageSize(int max_message_size) {
+  ServerBuilder& SetMaxMessageSize(int max_message_size) {
     max_message_size_ = max_message_size;
+    return *this;
   }
 
-  /// Set the compression options to be used by the server.
-  void SetCompressionOptions(const grpc_compression_options& options) {
-    compression_options_ = options;
-  }
+  /// Set the support status for compression algorithms. All algorithms are
+  /// enabled by default.
+  ///
+  /// Incoming calls compressed with an unsupported algorithm will fail with
+  /// GRPC_STATUS_UNIMPLEMENTED.
+  ServerBuilder& SetCompressionAlgorithmSupportStatus(
+      grpc_compression_algorithm algorithm, bool enabled);
+
+  /// The default compression level to use for all channel calls in the
+  /// absence of a call-specific level.
+  ServerBuilder& SetDefaultCompressionLevel(grpc_compression_level level);
+
+  /// The default compression algorithm to use for all channel calls in the
+  /// absence of a call-specific level. Note that it overrides any compression
+  /// level set by \a SetDefaultCompressionLevel.
+  ServerBuilder& SetDefaultCompressionAlgorithm(
+      grpc_compression_algorithm algorithm);
 
-  void SetOption(std::unique_ptr<ServerBuilderOption> option);
+  ServerBuilder& SetOption(std::unique_ptr<ServerBuilderOption> option);
 
   /// Tries to bind \a server to the given \a addr.
   ///
@@ -101,9 +115,9 @@ class ServerBuilder {
   /// number. \a nullptr otherwise.
   ///
   // TODO(dgq): the "port" part seems to be a misnomer.
-  void AddListeningPort(const grpc::string& addr,
-                        std::shared_ptr<ServerCredentials> creds,
-                        int* selected_port = nullptr);
+  ServerBuilder& AddListeningPort(const grpc::string& addr,
+                                  std::shared_ptr<ServerCredentials> creds,
+                                  int* selected_port = nullptr);
 
   /// Add a completion queue for handling asynchronous services
   /// Caller is required to keep this completion queue live until
@@ -144,7 +158,6 @@ class ServerBuilder {
   };
 
   int max_message_size_;
-  grpc_compression_options compression_options_;
   std::vector<std::unique_ptr<ServerBuilderOption>> options_;
   std::vector<std::unique_ptr<NamedService>> services_;
   std::vector<Port> ports_;
@@ -152,6 +165,15 @@ class ServerBuilder {
   std::shared_ptr<ServerCredentials> creds_;
   std::map<grpc::string, std::unique_ptr<ServerBuilderPlugin>> plugins_;
   AsyncGenericService* generic_service_;
+  struct {
+    bool is_set;
+    grpc_compression_level level;
+  } maybe_default_compression_level_;
+  struct {
+    bool is_set;
+    grpc_compression_algorithm algorithm;
+  } maybe_default_compression_algorithm_;
+  uint32_t enabled_compression_algorithms_bitset_;
 };
 
 }  // namespace grpc
diff --git a/include/grpc/compression.h b/include/grpc/compression.h
index 8de4b133d4..22bcf0e302 100644
--- a/include/grpc/compression.h
+++ b/include/grpc/compression.h
@@ -51,7 +51,8 @@ GRPCAPI int grpc_compression_algorithm_parse(
     grpc_compression_algorithm *algorithm);
 
 /** Updates \a name with the encoding name corresponding to a valid \a
- * algorithm.  Returns 1 upon success, 0 otherwise. */
+ * algorithm. Note that \a name is statically allocated and must *not* be freed.
+ * Returns 1 upon success, 0 otherwise. */
 GRPCAPI int grpc_compression_algorithm_name(
     grpc_compression_algorithm algorithm, char **name);
 
diff --git a/include/grpc/impl/codegen/compression_types.h b/include/grpc/impl/codegen/compression_types.h
index 8d2ec3b9d7..9065d1edd0 100644
--- a/include/grpc/impl/codegen/compression_types.h
+++ b/include/grpc/impl/codegen/compression_types.h
@@ -35,11 +35,17 @@
 #define GRPC_IMPL_CODEGEN_COMPRESSION_TYPES_H
 
 #include <grpc/impl/codegen/port_platform.h>
+#include <stdbool.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
+/** To be used as initial metadata key for the request of a concrete compression
+ * algorithm */
+#define GRPC_COMPRESSION_REQUEST_ALGORITHM_MD_KEY \
+  "grpc-internal-encoding-request"
+
 /** To be used in channel arguments */
 #define GRPC_COMPRESSION_CHANNEL_DEFAULT_ALGORITHM \
   "grpc.default_compression_algorithm"
@@ -74,15 +80,24 @@ typedef struct grpc_compression_options {
    */
   uint32_t enabled_algorithms_bitset;
 
-  /** The default channel compression algorithm. It'll be used in the absence of
+  /** The default channel compression level. It'll be used in the absence of
    * call specific settings. This option corresponds to the channel argument key
-   * behind \a GRPC_COMPRESSION_CHANNEL_DEFAULT_ALGORITHM */
-  grpc_compression_algorithm default_compression_algorithm;
+   * behind \a GRPC_COMPRESSION_CHANNEL_DEFAULT_LEVEL. If present, takes
+   * precedence over \a default_algorithm.
+   * TODO(dgq): currently only available for server channels. */
+  struct {
+    bool is_set;
+    grpc_compression_level level;
+  } default_level;
 
-  /** The default channel compression level. It'll be used in the absence of
+  /** The default channel compression algorithm. It'll be used in the absence of
    * call specific settings. This option corresponds to the channel argument key
-   * behind \a GRPC_COMPRESSION_CHANNEL_DEFAULT_LEVEL */
-  grpc_compression_algorithm default_compression_level;
+   * behind \a GRPC_COMPRESSION_CHANNEL_DEFAULT_ALGORITHM. */
+  struct {
+    bool is_set;
+    grpc_compression_algorithm algorithm;
+  } default_algorithm;
+
 } grpc_compression_options;
 
 #ifdef __cplusplus
diff --git a/include/grpc/impl/codegen/grpc_types.h b/include/grpc/impl/codegen/grpc_types.h
index 7181be4a34..c51ffa4493 100644
--- a/include/grpc/impl/codegen/grpc_types.h
+++ b/include/grpc/impl/codegen/grpc_types.h
@@ -334,6 +334,12 @@ typedef struct grpc_op {
     struct {
       size_t count;
       grpc_metadata *metadata;
+      /** If \a is_set, \a compression_level will be used for the call.
+       * Otherwise, \a compression_level won't be considered */
+      struct {
+        uint8_t is_set;
+        grpc_compression_level level;
+      } maybe_compression_level;
     } send_initial_metadata;
     grpc_byte_buffer *send_message;
     struct {