Line data    Source code

       1             : #pragma once
       2             : 
       3             : #include "envoy/common/pure.h"
       4             : #include "envoy/config/typed_config.h"
       5             : #include "envoy/server/filter_config.h"
       6             : #include "envoy/tracing/tracer.h"
       7             : 
       8             : #include "source/common/protobuf/protobuf.h"
       9             : 
      10             : namespace Envoy {
      11             : namespace Server {
      12             : namespace Configuration {
      13             : 
      14             : /**
      15             :  * Context passed to HTTP tracers to access server resources.
      16             :  */
      17             : class TracerFactoryContext {
      18             : public:
      19          96 :   virtual ~TracerFactoryContext() = default;
      20             : 
      21             :   /**
      22             :    * @return ServerFactoryContext which lifetime is no shorter than the server.
      23             :    */
      24             :   virtual ServerFactoryContext& serverFactoryContext() PURE;
      25             : 
      26             :   /**
      27             :    * @return ProtobufMessage::ValidationVisitor& validation visitor for tracer configuration
      28             :    *         messages.
      29             :    */
      30             :   virtual ProtobufMessage::ValidationVisitor& messageValidationVisitor() PURE;
      31             : };
      32             : 
      33             : using TracerFactoryContextPtr = std::unique_ptr<TracerFactoryContext>;
      34             : 
      35             : /**
      36             :  * Implemented by each Tracer and registered via Registry::registerFactory() or the convenience
      37             :  * class RegisterFactory.
      38             :  */
      39             : class TracerFactory : public Config::TypedFactory {
      40             : public:
      41           0 :   ~TracerFactory() override = default;
      42             : 
      43             :   /**
      44             :    * Create a particular trace driver implementation. If the implementation is unable to produce
      45             :    * a trace driver with the provided parameters, it should throw an EnvoyException in the case
      46             :    * of general error or a Json::Exception if the json configuration is erroneous. The returned
      47             :    * pointer should always be valid.
      48             :    *
      49             :    * NOTE: Due to the corner case of OpenCensus, who can only support a single tracing
      50             :    *       configuration per entire process, the returned Driver instance is not guaranteed
      51             :    *       to be unique.
      52             :    *       That is why the return type has been changed to std::shared_ptr<> instead of a more
      53             :    *       idiomatic std::unique_ptr<>.
      54             :    *
      55             :    * @param config supplies the proto configuration for the Tracer
      56             :    * @param context supplies the factory context
      57             :    */
      58             :   virtual Tracing::DriverSharedPtr createTracerDriver(const Protobuf::Message& config,
      59             :                                                       TracerFactoryContext& context) PURE;
      60             : 
      61          16 :   std::string category() const override { return "envoy.tracers"; }
      62             : };
      63             : 
      64             : } // namespace Configuration
      65             : } // namespace Server
      66             : } // namespace Envoy