create URL codec

pkg/url/log.go

@@ -0,0 +1,9 @@
+package url
+
+import (
+	"protocol.realy.lol/pkg/lol"
+)
+
+var (
+	log, chk, errorf = lol.Main.Log, lol.Main.Check, lol.Main.Errorf
+)

pkg/url/url.go

@@ -0,0 +1,46 @@
+package url
+
+import (
+	"bytes"
+	"net/url"
+)
+
+type U struct{ uu []byte }
+
+// New creates a new URL codec.C from the provided URL, and validates it.
+func New[V ~string | []byte](ur V) (uu *U, err error) {
+	uu = new(U)
+	var UU *url.URL
+	if UU, err = url.Parse(string(ur)); chk.E(err) {
+		return
+	} else {
+		// if it is valid, store it
+		uu.uu = []byte(UU.String())
+	}
+	return
+}
+
+func (u *U) String() string   { return string(u.uu) }
+func (u *U) Bytes() []byte    { return u.uu }
+func (u *U) Equal(u2 *U) bool { return bytes.Equal(u.uu, u2.uu) }
+
+func (u *U) Marshal(dst []byte) (result []byte, err error) {
+	result = append(append(dst, u.uu...), '\n')
+	return
+}
+
+func (u *U) Unmarshal(data []byte) (rem []byte, err error) {
+	rem = data
+	for i, v := range rem {
+		if v == '\n' {
+			u.uu = rem[:i]
+			rem = rem[i+1:]
+			break
+		}
+	}
+	// validate the URL and return error if not valid.
+	if _, err = url.Parse(string(u.uu)); chk.E(err) {
+		return
+	}
+	return
+}

pkg/url/url_test.go

@@ -0,0 +1,29 @@
+package url
+
+import (
+	"testing"
+)
+
+func TestU_Marshal_Unmarshal(t *testing.T) {
+	u := "https://example.com/path/to/resource"
+	var err error
+	var u1 *U
+	if u1, err = New(u); chk.E(err) {
+		t.Fatal(err)
+	}
+	var m1 []byte
+	if m1, err = u1.Marshal(nil); chk.E(err) {
+		t.Fatal(err)
+	}
+	u2 := new(U)
+	var rem []byte
+	if rem, err = u2.Unmarshal(m1); chk.E(err) {
+		t.Fatal(err)
+	}
+	if len(rem) > 0 {
+		t.Fatalf("'%s' should be empty", string(rem))
+	}
+	if !u2.Equal(u1) {
+		t.Fatalf("u1 should be equal to u2: '%s' != '%s'", u1, u2)
+	}
+}