paseto/v4: implements API to Pack and Unpack Message for PublicMode

The Pack method returns the signed [paseto.Message] as public token.
The token then verified and decoded into Message using the Unpack method.

1 files changed, 115 insertions, 0 deletions

diff --git a/lib/paseto/v4/public_mode_example_test.go b/lib/paseto/v4/public_mode_example_test.go
index 38c3df0f..7d2ee53a 100644
--- a/lib/paseto/v4/public_mode_example_test.go
+++ b/lib/paseto/v4/public_mode_example_test.go
@@ -4,9 +4,14 @@
 package pasetov4
 
 import (
+	"encoding/base64"
 	"encoding/hex"
+	"encoding/json"
 	"fmt"
 	"log"
+	"strings"
+
+	"git.sr.ht/~shulhan/pakakeh.go/lib/paseto"
 )
 
 func ExamplePublicMode() {
@@ -35,3 +40,113 @@ func ExamplePublicMode() {
 	// {"data":"signed message!"}
 	// {"kid":1000}
 }
+
+type DummyData struct {
+	Email string `json:"email"`
+}
+type DummyFooterData struct {
+	Quote string `json:"quote"`
+}
+
+func ExamplePublicMode_Pack() {
+	createPeer := func(id, secret string) (peer paseto.Peer, pmode *PublicMode) {
+		seed, err := hex.DecodeString(secret)
+		if err != nil {
+			log.Fatal(err)
+		}
+		pmode = NewPublicMode(seed)
+		peer = paseto.Peer{
+			ID:      id,
+			Private: pmode.PrivateKey,
+			Public:  pmode.PublicKey,
+		}
+		return peer, pmode
+	}
+	sender, senderpm := createPeer(
+		`john@example.com`,
+		`b4cbfb43df4ce210727d953e4a713307fa19bb7d9f85041438d9e11b942a3774`,
+	)
+	receiver, _ := createPeer(
+		`jane@example.org`,
+		`2222222222222222222222222222222222222222222222222222222222222222`,
+	)
+
+	sendMsg := paseto.NewMessage(sender, receiver, `hello`)
+	sendMsg.Payload.Data = DummyData{
+		Email: `hello@example.com`,
+	}
+	sendMsg.Footer.Data = DummyFooterData{
+		Quote: `Live to eat`,
+	}
+
+	token, err := senderpm.Pack(*sendMsg, nil)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	pieces := strings.Split(token, `.`)
+	fmt.Printf("Header: %s.%s\n", pieces[0], pieces[1])
+
+	paysig, _ := base64.RawURLEncoding.DecodeString(pieces[2])
+	payload := paysig[:len(paysig)-64]
+	pdata := paseto.Payload{
+		Data: &DummyData{},
+	}
+	_ = json.Unmarshal(payload, &pdata)
+	fmt.Printf("Payload.Data: %+v\n", pdata.Data)
+
+	footer, _ := base64.RawURLEncoding.DecodeString(pieces[3])
+	fmt.Printf("Footer: %s", footer)
+
+	// Output:
+	// Header: v4.public
+	// Payload.Data: &{Email:hello@example.com}
+	// Footer: {"data":{"quote":"Live to eat"},"peer_id":"john@example.com"}
+}
+
+func ExamplePublicMode_Unpack() {
+	createPeer := func(id, secret string) (peer paseto.Peer, pmode *PublicMode) {
+		seed, err := hex.DecodeString(secret)
+		if err != nil {
+			log.Fatal(err)
+		}
+		pmode = NewPublicMode(seed)
+		peer = paseto.Peer{
+			ID:      id,
+			Private: pmode.PrivateKey,
+			Public:  pmode.PublicKey,
+		}
+		return peer, pmode
+	}
+	sender, _ := createPeer(
+		`john@example.com`,
+		`b4cbfb43df4ce210727d953e4a713307fa19bb7d9f85041438d9e11b942a3774`,
+	)
+	_, recvpm := createPeer(
+		`jane@example.org`,
+		`2222222222222222222222222222222222222222222222222222222222222222`,
+	)
+	recvpm.AddPeer(sender)
+
+	token := `v4.public.eyJpc3MiOiJqb2huQGV4YW1wbGUuY29tIiwic3ViIjoiaGVsbG8iLCJhdWQiOiJqYW5lQGV4YW1wbGUub3JnIiwiZXhwIjoxNzc0ODE5NzYzLCJuYmYiOjE3NzQ4MTk3MDMsImlhdCI6MTc3NDgxOTcwMywiZGF0YSI6eyJlbWFpbCI6ImhlbGxvQGV4YW1wbGUuY29tIn19Ui741xeDUhQE2w31smKyAJ_d-fhMH20SRLkIY3lDbIBfj_tq7es9-H2wQR3q6EZZRPrlAPxEug712IEgomTnBA.eyJkYXRhIjp7InF1b3RlIjoiTGlmZSBpcyBmb3IgZWF0aW5nIn0sInBlZXJfaWQiOiJqb2huQGV4YW1wbGUuY29tIn0`
+	pdata := DummyData{}
+	fdata := DummyFooterData{}
+	recvMsg := paseto.Message{
+		Payload: paseto.Payload{
+			Data: &pdata,
+		},
+		Footer: paseto.Footer{
+			Data: &fdata,
+		},
+	}
+	err := recvpm.Unpack(token, nil, &recvMsg)
+	if err != nil {
+		log.Fatal(err)
+	}
+	fmt.Printf("%+v\n", recvMsg.Payload.Data)
+	fmt.Printf("%+v\n", recvMsg.Footer.Data)
+
+	// Output:
+	// &{Email:hello@example.com}
+	// &{Quote:Life is for eating}
+}