ddb

Documentation

Overview

Package ddb provides DynamoDB utility for Protobuf messages

Index

• Variables
• func BoolMapKey(s string) (bool, error)
• func IntMapKey[K ~int32 | ~int64](s string) (K, error)
• func Marshal(in any, os ...Option) (types.AttributeValue, error)
• func MarshalMappedMessage[K comparable, T any, TP ProtoMessage[T]](x map[K]TP, os ...Option) (types.AttributeValue, error)
• func MarshalMessage(x proto.Message, os ...Option) (a types.AttributeValue, err error)
• func MarshalRepeatedMessage[T any, TP ProtoMessage[T]](x []TP, os ...Option) (av types.AttributeValue, err error)
• func MarshalSet[T ~uint64 | ~uint32 | ~int32 | ~int64 | string | []byte](s []T, os ...Option) (types.AttributeValue, error)
• func StringMapKey(s string) (string, error)
• func UintMapKey[K ~uint32 | ~uint64](s string) (K, error)
• func Unmarshal(av types.AttributeValue, out any, os ...Option) error
• func UnmarshalMappedMessage[K comparable, T any, TP ProtoMessage[T]](m types.AttributeValue, fv func(s string) (K, error), os ...Option) (xm map[K]TP, err error)
• func UnmarshalMessage(m types.AttributeValue, x proto.Message, os ...Option) (err error)
• func UnmarshalRepeatedMessage[T any, TP ProtoMessage[T]](m types.AttributeValue, os ...Option) (xl []TP, err error)
• type Option
  • func Embed(v ddbv1.Encoding) Option
• type ProtoMessage

Variables

var (
	// ErrUnsupportedEmbedEncoding is returned when a unsupported embed encoding is used
	ErrUnsupportedEmbedEncoding = fmt.Errorf("unsupported embed encoding, supports: %s %s",
		ddbv1.Encoding_ENCODING_JSON, ddbv1.Encoding_ENCODING_DYNAMO)
)

Functions

func BoolMapKey

func BoolMapKey(s string) (bool, error)

BoolMapKey parses 's' as a boolean 'true' or 'false' value

func IntMapKey

func IntMapKey[K ~int32 | ~int64](s string) (K, error)

IntMapKey parses 's' as a signed integer value

func Marshal

func Marshal(in any, os ...Option) (types.AttributeValue, error)

Marshal will marshal basic types, and composite types that only hold basic types. It defers to the offical AWS sdk but is still put here to make it easier to change behaviour in the future.

func MarshalMappedMessage

func MarshalMappedMessage[K comparable, T any, TP ProtoMessage[T]](x map[K]TP, os ...Option) (types.AttributeValue, error)

MarshalMappedMessage takes a map of messages and marshals it to a dynamodb representation

func MarshalMessage

func MarshalMessage(x proto.Message, os ...Option) (a types.AttributeValue, err error)

MarshalMessage will marshal a protobuf message 'm' into an attribute value. It supports several well-known Protobuf types and if 'x' implements its own MarshalDynamoItem method it will be called to delegate the marshalling.

func MarshalRepeatedMessage

func MarshalRepeatedMessage[T any, TP ProtoMessage[T]](x []TP, os ...Option) (av types.AttributeValue, err error)

MarshalRepeatedMessage provides a generic function for marshalling a repeated field as long as the generated code provides the concrete type as the Type parameter.

func MarshalSet

func MarshalSet[T ~uint64 | ~uint32 | ~int32 | ~int64 | string | []byte](s []T, os ...Option) (types.AttributeValue, error)

MarshalSet will marshal a slice of 'T' to a dynamo set.

func StringMapKey

func StringMapKey(s string) (string, error)

StringMapKey parses 's' as a string map key

func UintMapKey

func UintMapKey[K ~uint32 | ~uint64](s string) (K, error)

UintMapKey parses 's' as an unsigned integer value

func Unmarshal

func Unmarshal(av types.AttributeValue, out any, os ...Option) error

Unmarshal will marshal basic types, and composite types that only hold basic types. It takes into account the embed encoding option.

func UnmarshalMappedMessage

func UnmarshalMappedMessage[K comparable, T any, TP ProtoMessage[T]](m types.AttributeValue, fv func(s string) (K, error), os ...Option) (xm map[K]TP, err error)

UnmarshalMappedMessage decodes the dynamodb representation of a map of messages

func UnmarshalMessage

func UnmarshalMessage(m types.AttributeValue, x proto.Message, os ...Option) (err error)

UnmarshalMessage will attempt to unmarshal 'm' into a protobuf message 'x'. It provides special support for several well-known protobuf message types. If 'x' implements the MarshalDynamoItem method it will be called to delegate the unmarshalling.

func UnmarshalRepeatedMessage

func UnmarshalRepeatedMessage[T any, TP ProtoMessage[T]](m types.AttributeValue, os ...Option) (xl []TP, err error)

UnmarshalRepeatedMessage provides a generic function for unmarshalling a repeated field of messages from the DynamoDB representation.

Types

type Option

type Option func(*opts)

Option configures the shared logic

func Embed

func Embed(v ddbv1.Encoding) Option

Embed option will signal to the marshalling/unmarshalling logic that the field id embedded in the Dynamo item and should be decoded.

type ProtoMessage

type ProtoMessage[T any] interface {
	proto.Message
	*T
}

ProtoMessage is a constraint to a protobuf message pointer.