github.com/google/cloudprober@v0.11.3/rds/server/server.go (about)

     1  // Copyright 2018 The Cloudprober Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  /*
    16  Package server provides a ResourceDiscovery gRPC server implementation. It can
    17  either be used a standalone server, using the binary in the "cmd" subdirectory,
    18  or it can run as a part of the cloudprober binary.
    19  */
    20  package server
    21  
    22  import (
    23  	"context"
    24  	"fmt"
    25  
    26  	"github.com/google/cloudprober/logger"
    27  	"github.com/google/cloudprober/rds/file"
    28  	"github.com/google/cloudprober/rds/gcp"
    29  	"github.com/google/cloudprober/rds/kubernetes"
    30  	pb "github.com/google/cloudprober/rds/proto"
    31  	spb "github.com/google/cloudprober/rds/proto"
    32  	configpb "github.com/google/cloudprober/rds/server/proto"
    33  	"google.golang.org/grpc"
    34  )
    35  
    36  // Server implements a ResourceDiscovery gRPC server.
    37  type Server struct {
    38  	providers map[string]Provider
    39  	l         *logger.Logger
    40  }
    41  
    42  // Provider is a resource provider, e.g. GCP provider.
    43  type Provider interface {
    44  	ListResources(req *pb.ListResourcesRequest) (*pb.ListResourcesResponse, error)
    45  }
    46  
    47  // ListResources implements the ListResources method of the ResourceDiscovery
    48  // service.
    49  func (s *Server) ListResources(ctx context.Context, req *pb.ListResourcesRequest) (*pb.ListResourcesResponse, error) {
    50  	p := s.providers[req.GetProvider()]
    51  	if p == nil {
    52  		return nil, fmt.Errorf("provider %s is not supported", req.GetProvider())
    53  	}
    54  	return p.ListResources(req)
    55  }
    56  
    57  func (s *Server) initProviders(c *configpb.ServerConf) error {
    58  	var p Provider
    59  	var err error
    60  	for _, pc := range c.GetProvider() {
    61  		id := pc.GetId()
    62  		switch pc.Config.(type) {
    63  		case *configpb.Provider_FileConfig:
    64  			if id == "" {
    65  				id = file.DefaultProviderID
    66  			}
    67  			s.l.Infof("rds.server: adding file provider with id: %s", id)
    68  			if p, err = file.New(pc.GetFileConfig(), s.l); err != nil {
    69  				return err
    70  			}
    71  		case *configpb.Provider_GcpConfig:
    72  			if id == "" {
    73  				id = gcp.DefaultProviderID
    74  			}
    75  			s.l.Infof("rds.server: adding GCP provider with id: %s", id)
    76  			if p, err = gcp.New(pc.GetGcpConfig(), s.l); err != nil {
    77  				return err
    78  			}
    79  		case *configpb.Provider_KubernetesConfig:
    80  			if id == "" {
    81  				id = kubernetes.DefaultProviderID
    82  			}
    83  			s.l.Infof("rds.server: adding Kubernetes provider with id: %s", id)
    84  			if p, err = kubernetes.New(pc.GetKubernetesConfig(), s.l); err != nil {
    85  				return err
    86  			}
    87  		}
    88  		s.providers[id] = p
    89  	}
    90  	return nil
    91  }
    92  
    93  // New creates a new instance of the ResourceDiscovery Server using the server
    94  // conf.
    95  func New(initCtx context.Context, c *configpb.ServerConf, providers map[string]Provider, l *logger.Logger) (*Server, error) {
    96  	srv := &Server{
    97  		providers: make(map[string]Provider),
    98  		l:         l,
    99  	}
   100  
   101  	var err error
   102  
   103  	if err = srv.initProviders(c); err != nil {
   104  		return nil, err
   105  	}
   106  
   107  	// If providers are not nil. This option is mainly for testing.
   108  	if providers != nil {
   109  		for prefix, p := range providers {
   110  			srv.providers[prefix] = p
   111  		}
   112  	}
   113  
   114  	return srv, nil
   115  }
   116  
   117  // RegisterWithGRPC registers the RDS servers with the given gRPC server.
   118  func (s *Server) RegisterWithGRPC(grpcServer *grpc.Server) {
   119  	spb.RegisterResourceDiscoveryServer(grpcServer, s)
   120  }