populatePackagePB.go


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package debian

import (
	"google.golang.org/protobuf/proto"
	"google.golang.org/protobuf/reflect/protoreflect"

	"go.wit.com/lib/config"
)

func SetString(pb proto.Message, varname string, varvalue string) (bool, error) {
	msg := pb.ProtoReflect() // This is the entry point to the reflection API.

	descriptor := msg.Descriptor() // Get the message's descriptor, which contains metadata about its fields.

	fieldName := protoreflect.Name(varname)
	fieldDescriptor := descriptor.Fields().ByName(fieldName)

	if fieldDescriptor == nil {
		return false, config.ErrProtoNoVarName
	}

	if fieldDescriptor.Kind() != protoreflect.StringKind {
		// The field exists but is not a string, so we can't return it as one.
		return false, config.ErrProtoVarNotString
	}

	valueToSet := protoreflect.ValueOfString(varvalue)

	// 6. If the field exists and is a string, get its value.
	// The value is returned as a protoreflect.Value.
	msg.Set(fieldDescriptor, valueToSet)

	// 7. Convert the protoreflect.Value to a native Go string.
	return true, nil
}