prototransform

README

proto-transform

A small go-lang library that accepts proto file message definitions in protofbuf serialisation format (see proto target in Makefile for how to create these) and a message mapping and allows transformation from one message to another purely off of these mappings.

---

Usage

transform_test.go has test cases illustrating usage but in brief

fileDescriptorProto, _ := os.ReadFile("models.pb")
	messageMappings := &TransformMappings{
		TransformMappings: []TransformMapping{
			{
				FromMessageName: "WorkflowState",
				ToMessageName:   "Compensation",
				FieldMappings: []FieldMapping{
					{
						FromFieldName: "unixTimeNano",
						ToFieldName:   "totalSteps",
					},
					{
						FromFieldName: "elementName",
						ToFieldName:   "forTrackingId",
					},
					{
						FromFieldName: "timer.lastFired",
						ToFieldName:   "step",
					},
				},
			},
		},
	}

transformer, _ := NewTransformer(messageMappings, fileDescriptorProto) // can take multiple fileDescriptor proto files

compensationProtoMessage, err := transform.Transform(workflowStateProtoMessage, "Compensation")

Roadmap

potential improvements:

• index or key based mapping access for list or map type fields in the mapping syntax

License

see LICENSE

Documentation

Index

• type Action
• type ActionResult
• type FieldMapping
• type Get
• type Set
• type TransformMapping
• type TransformMappings
• type Transformer
  • func NewTransformer(transformMappings *TransformMappings, fileDescriptorProtos ...[]byte) (Transformer, error)
  • func NewTransformerRawProto(transformMappings *TransformMappings, rawProtos embed.FS, ...) (Transformer, error)
  • func (t Transformer) Transform(ctx context.Context, f proto.Message, toMessageName string) (proto.Message, error)
  • func (t Transformer) TransformProtoBytes(ctx context.Context, fromMessageName string, fromMessageBytes []byte, ...) (proto.Message, error)

Types

type Action

type Action interface {
	// contains filtered or unexported methods
}

type ActionResult

type ActionResult struct {
	// contains filtered or unexported fields
}

type FieldMapping

type FieldMapping struct {
	FromFieldName string `json:"fromFieldName"`
	ToFieldName   string `json:"toFieldName"`
}

type Get

type Get struct{}

type Set

type Set struct {
	// contains filtered or unexported fields
}

type TransformMapping

type TransformMapping struct {
	FromMessageName string         `json:"fromMessageName"`
	ToMessageName   string         `json:"toMessageName"`
	FieldMappings   []FieldMapping `json:"fieldMappings"`
}

type TransformMappings

type TransformMappings struct {
	TransformMappings  []TransformMapping          `json:"transformMappings"`
	FromToIdx          map[string]TransformMapping `json:"-"`
	MessageNameAliases map[string]string           `json:"messageNameAliases"`
}

type Transformer

type Transformer struct {
	// contains filtered or unexported fields
}

func NewTransformer

func NewTransformer(transformMappings *TransformMappings, fileDescriptorProtos ...[]byte) (Transformer, error)

func NewTransformerRawProto

func NewTransformerRawProto(transformMappings *TransformMappings, rawProtos embed.FS, topLevelProtoDirName string) (Transformer, error)

func (Transformer) Transform

func (t Transformer) Transform(ctx context.Context, f proto.Message, toMessageName string) (proto.Message, error)

func (Transformer) TransformProtoBytes

func (t Transformer) TransformProtoBytes(ctx context.Context, fromMessageName string, fromMessageBytes []byte, toMessageName string) (proto.Message, error)