[ovsp4rt] Implement Client class (#713)

- Implemented the `Client` `ClientInterface`, and `ClientMock`
  classes, to abstract the interface to the P4Runtime server.

Signed-off-by: Derek Foster <justffoulkes@gmail.com>

ovs-p4rt/sidecar/CMakeLists.txt

@@ -4,8 +4,11 @@
 # SPDX-License-Identifier: Apache 2.0
 #
 
+option(BUILD_CLIENT  "Build ovs-p4rt with Client class" OFF)
 option(BUILD_JOURNAL "Build ovs-p4rt with Journal class" OFF)
-option(BUILD_SPIES "Build ovs-p4rt with spies" OFF)
+option(BUILD_SPIES   "Build ovs-p4rt spies library" OFF)
+
+mark_as_advanced(BUILD_CLIENT)
 mark_as_advanced(BUILD_JOURNAL)
 mark_as_advanced(BUILD_SPIES)
 
@@ -113,16 +116,23 @@ else()
     add_library(ovsp4rt_test ALIAS ovsp4rt)
 endif()
 
+#-----------------------------------------------------------------------
+# libovsp4rt_spies.a
+#-----------------------------------------------------------------------
+if(BUILD_SPIES)
+    add_subdirectory(spies)
+endif()
+
 #-----------------------------------------------------------------------
 # libovsp4rt_stubs.a
 #-----------------------------------------------------------------------
 add_subdirectory(stubs)
 
 #-----------------------------------------------------------------------
-# libovsp4rt_spies.a
+# libovsp4rt_client_o
 #-----------------------------------------------------------------------
-if(BUILD_SPIES)
-    add_subdirectory(spies)
+if(BUILD_CLIENT)
+    add_subdirectory(client)
 endif()
 
 #-----------------------------------------------------------------------
@@ -168,5 +178,5 @@ if(BUILD_TESTING)
 endif()
 
 add_custom_target(ovsp4rt-unit-tests
-  DEPENDS ${UNIT_TEST_NAMES}
+    DEPENDS ${UNIT_TEST_NAMES}
 )

ovs-p4rt/sidecar/client/CMakeLists.txt

@@ -0,0 +1,36 @@
+# CMake build file for ovs-p4rt/sidecar/client
+#
+# Copyright 2024 Intel Corporation
+# SPDX-License-Identifier: Apache 2.0
+#
+
+#-----------------------------------------------------------------------
+# ovsp4rt_client_o
+#-----------------------------------------------------------------------
+add_library(ovsp4rt_client_o OBJECT
+  ovsp4rt_client.cc
+  ovsp4rt_client.h
+  ovsp4rt_client_interface.h
+)
+
+target_include_directories(ovsp4rt_client_o PUBLIC
+  ${SIDECAR_SOURCE_DIR}
+)
+
+#-----------------------------------------------------------------------
+# libovsp4rt_client.a
+#-----------------------------------------------------------------------
+add_library(ovsp4rt_client STATIC
+  $<TARGET_OBJECTS:ovsp4rt_client_o>
+)
+
+#-----------------------------------------------------------------------
+# ovsp4rt_client_so
+#-----------------------------------------------------------------------
+add_library(ovsp4rt_client_so SHARED EXCLUDE_FROM_ALL
+  $<TARGET_OBJECTS:ovsp4rt_client_o>
+)
+
+set_target_properties(ovsp4rt_client_so PROPERTIES
+  OUTPUT_NAME ovsp4rt_client
+)

ovs-p4rt/sidecar/client/ovsp4rt_client.cc

@@ -0,0 +1,66 @@
+// Copyright 2022-2024 Intel Corporation
+// SPDX-License-Identifier: Apache-2.0
+
+#include "ovsp4rt_client.h"
+
+#include "absl/flags/flag.h"
+#include "absl/status/status.h"
+#include "absl/status/statusor.h"
+#include "session/ovsp4rt_credentials.h"
+#include "session/ovsp4rt_session.h"
+
+#define DEFAULT_ROLE_NAME "ovs-p4rt"
+
+ABSL_FLAG(uint64_t, device_id, 1, "P4Runtime device ID.");
+
+ABSL_FLAG(std::string, role_name, DEFAULT_ROLE_NAME, "P4 config role name.");
+
+namespace ovsp4rt {
+
+absl::Status Client::connect(const char* grpc_addr) {
+  // Start a new client session.
+  auto result = ovsp4rt::OvsP4rtSession::Create(
+      grpc_addr, GenerateClientCredentials(), absl::GetFlag(FLAGS_device_id),
+      absl::GetFlag(FLAGS_role_name));
+  if (!result.ok()) {
+    return result.status();
+  }
+
+  // Unwrap the session from the StatusOr object.
+  session_ = std::move(result).value();
+  return absl::OkStatus();
+}
+
+absl::Status Client::getPipelineConfig(::p4::config::v1::P4Info* p4info) {
+  return GetForwardingPipelineConfig(session_.get(), p4info);
+}
+
+::p4::v1::TableEntry* Client::initReadRequest(::p4::v1::ReadRequest* request) {
+  return SetupTableEntryToRead(session_.get(), request);
+}
+
+absl::StatusOr<::p4::v1::ReadResponse> Client::sendReadRequest(
+    const p4::v1::ReadRequest& request) {
+  return SendReadRequest(session_.get(), request);
+}
+
+::p4::v1::TableEntry* Client::initInsertRequest(
+    ::p4::v1::WriteRequest* request) {
+  return SetupTableEntryToInsert(session_.get(), request);
+}
+
+::p4::v1::TableEntry* Client::initModifyRequest(
+    ::p4::v1::WriteRequest* request) {
+  return SetupTableEntryToModify(session_.get(), request);
+}
+
+::p4::v1::TableEntry* Client::initDeleteRequest(
+    ::p4::v1::WriteRequest* request) {
+  return SetupTableEntryToDelete(session_.get(), request);
+}
+
+absl::Status Client::sendWriteRequest(const p4::v1::WriteRequest& request) {
+  return SendWriteRequest(session_.get(), request);
+}
+
+}  // namespace ovsp4rt

ovs-p4rt/sidecar/client/ovsp4rt_client.h

@@ -0,0 +1,77 @@
+// Copyright 2024 Intel Corporation
+// SPDX-License-Identifier: Apache-2.0
+
+#ifndef OVSP4RT_CLIENT_H_
+#define OVSP4RT_CLIENT_H_
+
+#include <stdint.h>
+
+#include <string>
+
+#include "absl/status/status.h"
+#include "absl/status/statusor.h"
+#include "ovsp4rt_client_interface.h"
+#include "p4/v1/p4runtime.pb.h"
+#include "session/ovsp4rt_session.h"
+
+namespace ovsp4rt {
+
+class Client : public ClientInterface {
+ public:
+  Client() {}
+  virtual ~Client() = default;
+
+  // Connects to the P4Runtime server.
+  virtual absl::Status connect(const char* grpc_addr);
+
+  // Returns a pointer to the ovsp4rt session object.
+  virtual OvsP4rtSession* session() const { return session_.get(); }
+
+  // Gets the pipeline configuration from the P4Runtime server.
+  virtual absl::Status getPipelineConfig(::p4::config::v1::P4Info* p4info);
+
+  //--------------------------------------------------------------------
+
+  // Initializes a Read Table Entry request message.
+  virtual ::p4::v1::TableEntry* initReadRequest(::p4::v1::ReadRequest* request);
+
+  // Sends a Read Table Entry request to the P4Runtime server.
+  virtual absl::StatusOr<p4::v1::ReadResponse> sendReadRequest(
+      const p4::v1::ReadRequest& request);
+
+  //--------------------------------------------------------------------
+
+  // Initializes an Insert Table Entry request message.
+  virtual ::p4::v1::TableEntry* initInsertRequest(
+      ::p4::v1::WriteRequest* request);
+
+  // Initializes a Modify Table Entry request message.
+  virtual ::p4::v1::TableEntry* initModifyRequest(
+      ::p4::v1::WriteRequest* request);
+
+  // Initializes a Delete Table Entry request message.
+  virtual ::p4::v1::TableEntry* initDeleteRequest(
+      ::p4::v1::WriteRequest* request);
+
+  // Initializes an Insert Table Entry or Delete Table Entry request
+  // message, depending on the value of the `insert_entry` parameter.
+  virtual ::p4::v1::TableEntry* initWriteRequest(
+      ::p4::v1::WriteRequest* request, bool insert_entry) {
+    if (insert_entry) {
+      return initInsertRequest(request);
+    } else {
+      return initDeleteRequest(request);
+    }
+  }
+
+  // Sends a Write Table Entry request to the P4Runtime server.
+  virtual absl::Status sendWriteRequest(const p4::v1::WriteRequest& request);
+
+ private:
+  // Pointer to a P4Runtime session object.
+  std::unique_ptr<ovsp4rt::OvsP4rtSession> session_;
+};
+
+}  // namespace ovsp4rt
+
+#endif  // OVSP4RT_CLIENT_H_

ovs-p4rt/sidecar/client/ovsp4rt_client_interface.h

@@ -0,0 +1,67 @@
+// Copyright 2024 Intel Corporation
+// SPDX-License-Identifier: Apache-2.0
+
+#ifndef OVSP4RT_CLIENT_INTERFACE_H_
+#define OVSP4RT_CLIENT_INTERFACE_H_
+
+#include "absl/status/status.h"
+#include "absl/status/statusor.h"
+#include "p4/v1/p4runtime.pb.h"
+#include "session/ovsp4rt_session.h"
+
+namespace ovsp4rt {
+
+class ClientInterface {
+ public:
+  virtual ~ClientInterface() = default;
+
+  // Connects to the P4Runtime server.
+  virtual absl::Status connect(const char* grpc_addr) = 0;
+
+  // Returns a pointer to the ovsp4rt session object.
+  virtual OvsP4rtSession* session() const = 0;
+
+  // Gets the pipeline configuration from the P4Runtime server.
+  virtual absl::Status getPipelineConfig(::p4::config::v1::P4Info* p4info) = 0;
+
+  //--------------------------------------------------------------------
+
+  // Initializes a Read Table Entry request message.
+  virtual ::p4::v1::TableEntry* initReadRequest(
+      ::p4::v1::ReadRequest* request) = 0;
+
+  // Sends a Read Table Entry request to the P4Runtime server.
+  virtual absl::StatusOr<p4::v1::ReadResponse> sendReadRequest(
+      const p4::v1::ReadRequest& request) = 0;
+
+  //--------------------------------------------------------------------
+
+  // Initializes an Insert Table Entry request message.
+  virtual ::p4::v1::TableEntry* initInsertRequest(
+      ::p4::v1::WriteRequest* request) = 0;
+
+  // Initializes a Modify Table Entry request message.
+  virtual ::p4::v1::TableEntry* initModifyRequest(
+      ::p4::v1::WriteRequest* request) = 0;
+
+  // Initializes a Delete Table Entry request message.
+  virtual ::p4::v1::TableEntry* initDeleteRequest(
+      ::p4::v1::WriteRequest* request) = 0;
+
+  // Initializes an Insert Table Entry or Delete Table Entry request
+  // message, depending on the value of the `insert_entry` parameter.
+  virtual ::p4::v1::TableEntry* initWriteRequest(
+      ::p4::v1::WriteRequest* request, bool insert_entry) = 0;
+
+  // Sends a Write Table Entry request to the P4Runtime server.
+  virtual absl::Status sendWriteRequest(
+      const p4::v1::WriteRequest& request) = 0;
+
+ protected:
+  // Default constructor. To be called by the Mock class instance only.
+  ClientInterface() {}
+};
+
+}  // namespace ovsp4rt
+
+#endif  // OVSP4RT_CLIENT_INTERFACE_H_

ovs-p4rt/sidecar/client/ovsp4rt_client_mock.h

@@ -0,0 +1,43 @@
+// Copyright 2024 Intel Corporation
+// SPDX-License-Identifier: Apache-2.0
+
+#ifndef OVSP4RT_CLIENT_MOCK_H_
+#define OVSP4RT_CLIENT_MOCK_H_
+
+#include "gmock/gmock.h"
+#include "ovsp4rt_client_interface.h"
+
+namespace ovsp4rt {
+
+class ClientMock : public ClientInterface {
+ public:
+  MOCK_METHOD(absl::Status, connect, (const char*));
+
+  MOCK_METHOD(OvsP4rtSession*, session, (), (const));
+
+  MOCK_METHOD(absl::Status, getPipelineConfig, (::p4::config::v1::P4Info*));
+
+  MOCK_METHOD(::p4::v1::TableEntry*, initReadRequest, (::p4::v1::ReadRequest*));
+
+  MOCK_METHOD(absl::StatusOr<p4::v1::ReadResponse>, sendReadRequest,
+              (const p4::v1::ReadRequest&));
+
+  MOCK_METHOD(::p4::v1::TableEntry*, initInsertRequest,
+              (::p4::v1::WriteRequest*));
+
+  MOCK_METHOD(::p4::v1::TableEntry*, initModifyRequest,
+              (::p4::v1::WriteRequest*));
+
+  MOCK_METHOD(::p4::v1::TableEntry*, initDeleteRequest,
+              (::p4::v1::WriteRequest*));
+
+  MOCK_METHOD(::p4::v1::TableEntry*, initWriteRequest,
+              (::p4::v1::WriteRequest*, bool));
+
+  MOCK_METHOD(absl::Status, sendWriteRequest,
+              (const p4::v1::WriteRequest& request));
+};
+
+}  // namespace ovsp4rt
+
+#endif  // OVSP4RT_CLIENT_MOCK_H_