github.com/googleapis/api-linter@v1.65.2/rules/aip0158/response_repeated_first_field.go (about)

     1  // Copyright 2020 Google LLC
     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  //     https://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  package aip0158
    16  
    17  import (
    18  	"github.com/googleapis/api-linter/lint"
    19  	"github.com/jhump/protoreflect/desc"
    20  )
    21  
    22  var responseRepeatedFirstField = &lint.MessageRule{
    23  	Name: lint.NewRuleName(158, "response-repeated-first-field"),
    24  	OnlyIf: func(m *desc.MessageDescriptor) bool {
    25  		return isPaginatedResponseMessage(m) && len(m.GetFields()) > 0
    26  	},
    27  	LintMessage: func(m *desc.MessageDescriptor) []lint.Problem {
    28  		// Sanity check: Is the first field (positionally) and the field with
    29  		// an ID of 1 actually the same field?
    30  		if m.GetFields()[0] != m.FindFieldByNumber(1) {
    31  			return []lint.Problem{{
    32  				Message:    "The first field of paginated RPCs must have a protobuf ID of 1.",
    33  				Descriptor: m.GetFields()[0],
    34  			}}
    35  		}
    36  
    37  		// Make sure the field is repeated.
    38  		if !m.GetFields()[0].IsRepeated() {
    39  			return []lint.Problem{{
    40  				Message:    "The first field of a paginated response should be repeated.",
    41  				Descriptor: m.GetFields()[0],
    42  			}}
    43  		}
    44  
    45  		return nil
    46  	},
    47  }