Comparison between Goa v1 vs. v3 about the design primitive types

Goa v3 changed the primitive types used to design from v1. This article compares v1 and v3 primitive types with Swagger data types.

Primitive types of v1

Source: https://godoc.org/gopkg.in/goadesign/goa.v1/design#pkg-constants

const (
    // Boolean is the type for a JSON boolean.
    Boolean = Primitive(BooleanKind)

    // Integer is the type for a JSON number without a fraction or exponent part.
    Integer = Primitive(IntegerKind)

    // Number is the type for any JSON number, including integers.
    Number = Primitive(NumberKind)

    // String is the type for a JSON string.
    String = Primitive(StringKind)

    // DateTime is the type for a JSON string parsed as a Go time.Time
    // DateTime expects an RFC3339 formatted value.
    DateTime = Primitive(DateTimeKind)

    // UUID is the type for a JSON string parsed as a Go uuid.UUID
    // UUID expects an RFC4122 formatted value.
    UUID = Primitive(UUIDKind)

    // Any is the type for an arbitrary JSON value (interface{} in Go).
    Any = Primitive(AnyKind)

    // File is the type for a file. This type can only be used in a multipart definition.
    File = Primitive(FileKind)
)

Primitive types of v3

Source: https://godoc.org/goa.design/goa/expr#pkg-constants

const (
    // Boolean is the type for a JSON boolean.
    Boolean = Primitive(BooleanKind)

    // Int is the type for a signed integer.
    Int = Primitive(IntKind)

    // Int32 is the type for a signed 32-bit integer.
    Int32 = Primitive(Int32Kind)

    // Int64 is the type for a signed 64-bit integer.
    Int64 = Primitive(Int64Kind)

    // UInt is the type for an unsigned integer.
    UInt = Primitive(UIntKind)

    // UInt32 is the type for an unsigned 32-bit integer.
    UInt32 = Primitive(UInt32Kind)

    // UInt64 is the type for an unsigned 64-bit integer.
    UInt64 = Primitive(UInt64Kind)

    // Float32 is the type for a 32-bit floating number.
    Float32 = Primitive(Float32Kind)

    // Float64 is the type for a 64-bit floating number.
    Float64 = Primitive(Float64Kind)

    // String is the type for a JSON string.
    String = Primitive(StringKind)

    // Bytes is the type for binary data.
    Bytes = Primitive(BytesKind)

    // Any is the type for an arbitrary JSON value (interface{} in Go).
    Any = Primitive(AnyKind)
)

Swagger data types

Source: https://github.com/OAI/OpenAPI-Specification/blob/master/versions/2.0.md#data-types

Common Name	type	format	Comments
integer	integer	int32	signed 32 bits
long	integer	int64	signed 64 bits
float	number	float
double	number	double
string	string
byte	string	byte	base64 encoded characters
binary	string	binary	any sequence of octets
boolean	boolean
date	string	date	As defined by full-date - RFC3339
dateTime	string	date-time	As defined by date-time - RFC3339
password	string	password	Used to hint UIs the input needs to be obscured.

Comparison

v3 has more types than v1 to support gRPC. DateTime and UUID are obsoleted but equivalent definitions can be described using the Format DSL. There are many more formats.

v1	v3	Swagger Common Name	Swagger type	Swagger format
Boolean	Boolean	boolean	boolean
Integer	Int	long	integer	int64
	Int32	integer	integer	int32
	Int64	long	integer	int64
	UInt	long	integer	int64
	UInt32	integer	integer	int32
	UInt64	long	integer	int64
Number	Float32	float	number	float
	Float64	double	number	double
String	String	string	string
DateTime	String + Format(FormatDateTime)	dateTime	string	date-time
UUID	String + Format(FormatUUID)		string	uuid
	String + Format(FormatDate)	date	string	date
	String + Format(FormatEmail)		string	email
	String + Format(FormatHostname)		string	hostname
	String + Format(FormatIPv4)		string	ipv4
	String + Format(FormatIPv6)		string	ipv6
	String + Format(FormatIP)		string	ip
	String + Format(FormatURI)		string	uri
	String + Format(FormatMAC)		string	mac
	String + Format(FormatCIDR)		string	cidr
	String + Format(FormatRegexp)		string	regexp
	String + Format(FormatJSON)		string	json
	String + Format(FormatRFC1123)		string	rfc1123
	Bytes	byte	string	byte
Any	Any		any
File			file