github.com/m3db/m3@v1.5.0/src/dbnode/encoding/proto/parse_schema.go (about)

     1  // Copyright (c) 2019 Uber Technologies, Inc.
     2  //
     3  // Permission is hereby granted, free of charge, to any person obtaining a copy
     4  // of this software and associated documentation files (the "Software"), to deal
     5  // in the Software without restriction, including without limitation the rights
     6  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
     7  // copies of the Software, and to permit persons to whom the Software is
     8  // furnished to do so, subject to the following conditions:
     9  //
    10  // The above copyright notice and this permission notice shall be included in
    11  // all copies or substantial portions of the Software.
    12  //
    13  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
    14  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
    15  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
    16  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
    17  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
    18  // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
    19  // THE SOFTWARE.
    20  
    21  package proto
    22  
    23  import (
    24  	"fmt"
    25  
    26  	"github.com/jhump/protoreflect/desc"
    27  	"github.com/jhump/protoreflect/desc/protoparse"
    28  )
    29  
    30  // ParseProtoSchema parses a Protobuf schema.
    31  // TODO(rartoul): This is temporary code that will eventually be replaced with
    32  // storing the schemas in etcd.
    33  func ParseProtoSchema(filePath string, messageName string) (*desc.MessageDescriptor, error) {
    34  	fds, err := protoparse.Parser{}.ParseFiles(filePath)
    35  	if err != nil {
    36  		return nil, fmt.Errorf(
    37  			"error parsing proto schema: %s, err: %v", filePath, err)
    38  	}
    39  
    40  	if len(fds) != 1 {
    41  		return nil, fmt.Errorf(
    42  			"expected to parse %s into one file descriptor but parsed: %d",
    43  			filePath, len(fds))
    44  	}
    45  
    46  	schema := fds[0].FindMessage(messageName)
    47  	if schema == nil {
    48  		return nil, fmt.Errorf(
    49  			"expected to find message with name '%s' in %s, but did not",
    50  			messageName, filePath,
    51  		)
    52  	}
    53  
    54  	return schema, nil
    55  }