implement auth, closed and close envelopes

pkg/interfaces/codec/codec.go

@@ -0,0 +1,47 @@
+package codec
+
+import (
+	"io"
+)
+
+type I interface {
+	MarshalWrite(w io.Writer) (err error)
+	UnmarshalRead(r io.Reader) (err error)
+}
+
+// Envelope is an interface for the nostr "envelope" message formats, a JSON
+// array with the first field an upper case string that provides type
+// information, in combination with the context of the side sending it (relay or
+// client).
+type Envelope interface {
+	// Label returns the (uppercase) string that signifies the type of message.
+	Label() string
+	// Write outputs the envelope to an io.Writer
+	Write(w io.Writer) (err error)
+	// JSON is a somewhat simplified version of the
+	// json.Marshaler/json.Unmarshaler that has no error for the Marshal side of
+	// the operation.
+	JSON
+}
+
+// JSON is a somewhat simplified version of the json.Marshaler/json.Unmarshaler
+// that has no error for the Marshal side of the operation.
+type JSON interface {
+	// Marshal converts the data of the type into JSON, appending it to the provided
+	// slice and returning the extended slice.
+	Marshal(dst []byte) (b []byte)
+	// Unmarshal decodes a JSON form of a type back into the runtime form, and
+	// returns whatever remains after the type has been decoded out.
+	Unmarshal(b []byte) (r []byte, err error)
+}
+
+// Binary is a similarly simplified form of the stdlib binary Marshal/Unmarshal
+// server. Same as JSON it does not have an error for the MarshalBinary.
+type Binary interface {
+	// MarshalBinary converts the data of the type into binary form, appending
+	// it to the provided slice.
+	MarshalBinary(dst []byte) (b []byte)
+	// UnmarshalBinary decodes a binary form of a type back into the runtime
+	// form, and returns whatever remains after the type has been decoded out.
+	UnmarshalBinary(b []byte) (r []byte, err error)
+}