github.com/containerd/Containerd@v1.4.13/namespaces/ttrpc.go (about)

     1  /*
     2     Copyright The containerd Authors.
     3  
     4     Licensed under the Apache License, Version 2.0 (the "License");
     5     you may not use this file except in compliance with the License.
     6     You may obtain a copy of the License at
     7  
     8         http://www.apache.org/licenses/LICENSE-2.0
     9  
    10     Unless required by applicable law or agreed to in writing, software
    11     distributed under the License is distributed on an "AS IS" BASIS,
    12     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13     See the License for the specific language governing permissions and
    14     limitations under the License.
    15  */
    16  
    17  package namespaces
    18  
    19  import (
    20  	"context"
    21  
    22  	"github.com/containerd/ttrpc"
    23  )
    24  
    25  const (
    26  	// TTRPCHeader defines the header name for specifying a containerd namespace
    27  	TTRPCHeader = "containerd-namespace-ttrpc"
    28  )
    29  
    30  func copyMetadata(src ttrpc.MD) ttrpc.MD {
    31  	md := ttrpc.MD{}
    32  	for k, v := range src {
    33  		md[k] = append(md[k], v...)
    34  	}
    35  	return md
    36  }
    37  
    38  func withTTRPCNamespaceHeader(ctx context.Context, namespace string) context.Context {
    39  	md, ok := ttrpc.GetMetadata(ctx)
    40  	if !ok {
    41  		md = ttrpc.MD{}
    42  	} else {
    43  		md = copyMetadata(md)
    44  	}
    45  	md.Set(TTRPCHeader, namespace)
    46  	return ttrpc.WithMetadata(ctx, md)
    47  }
    48  
    49  func fromTTRPCHeader(ctx context.Context) (string, bool) {
    50  	return ttrpc.GetMetadataValue(ctx, TTRPCHeader)
    51  }