dubbo.apache.org/dubbo-go/v3@v3.1.1/common/extension/metadata_service.go (about)

     1  /*
     2   * Licensed to the Apache Software Foundation (ASF) under one or more
     3   * contributor license agreements.  See the NOTICE file distributed with
     4   * this work for additional information regarding copyright ownership.
     5   * The ASF licenses this file to You under the Apache License, Version 2.0
     6   * (the "License"); you may not use this file except in compliance with
     7   * the License.  You may obtain a copy of the License at
     8   *
     9   *     http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   */
    17  
    18  package extension
    19  
    20  import (
    21  	"fmt"
    22  )
    23  
    24  import (
    25  	perrors "github.com/pkg/errors"
    26  )
    27  
    28  import (
    29  	"dubbo.apache.org/dubbo-go/v3/common/constant"
    30  	"dubbo.apache.org/dubbo-go/v3/metadata/service"
    31  )
    32  
    33  type localMetadataServiceCreator func() (service.MetadataService, error)
    34  
    35  var (
    36  	localMetadataServiceInsMap = make(map[string]localMetadataServiceCreator, 2)
    37  )
    38  
    39  // SetLocalMetadataService will store the msType => creator pair
    40  func SetLocalMetadataService(key string, creator localMetadataServiceCreator) {
    41  	localMetadataServiceInsMap[key] = creator
    42  }
    43  
    44  // GetLocalMetadataService will create a local MetadataService instance
    45  func GetLocalMetadataService(key string) (service.MetadataService, error) {
    46  	if key == "" {
    47  		key = constant.DefaultKey
    48  	}
    49  	if creator, ok := localMetadataServiceInsMap[key]; ok {
    50  		return creator()
    51  	}
    52  	return nil, perrors.New(fmt.Sprintf("could not find the metadata service creator for metadataType: local, " +
    53  		"please check whether you have imported relative packages, " +
    54  		"local - dubbo.apache.org/dubbo-go/v3/metadata/service/local"))
    55  }