pgp: add attach key command

Add compose command ("attach-key") to attach the public key associated
with the sending account. Public key is attached in ascii armor format,
with the mimetype set according to RFC 3156 ("application/pgp-keys").

Signed-off-by: Tim Culverhouse <tim@timculverhouse.com>
Tested-by: Koni Marti <koni.marti@gmail.com>

commands/compose/attach-key.go

@@ -0,0 +1,32 @@
+package compose
+
+import (
+	"errors"
+
+	"git.sr.ht/~rjarry/aerc/widgets"
+)
+
+type AttachKey struct{}
+
+func init() {
+	register(AttachKey{})
+}
+
+func (AttachKey) Aliases() []string {
+	return []string{"attach-key"}
+}
+
+func (AttachKey) Complete(aerc *widgets.Aerc, args []string) []string {
+	return nil
+}
+
+func (AttachKey) Execute(aerc *widgets.Aerc, args []string) error {
+	if len(args) != 1 {
+		return errors.New("Usage: attach-key")
+	}
+
+	composer, _ := aerc.SelectedTab().(*widgets.Composer)
+
+	composer.SetAttachKey(!composer.AttachKey())
+	return nil
+}