upd: finish url_gen function

src/hotp.js

@@ -56,4 +56,17 @@ export class HOTP extends OTP {
             return false;
         }
     }
+
+    /*＊
+     * Generate a url with HOTP instance.
+     *
+     * @param {issuer}
+     * @type {String} 
+     * @desc maybe it is the Service name
+     *
+     * @return {String}
+     */
+    url_gen(issuer="") {
+        return super.url_gen(issuer, "hotp");
+    }
 }

src/otp.js

@@ -77,5 +77,21 @@ export class OTP  {
         return str_code;
     }
 
+    /*＊
+     * Generate a url with TOTP or HOTP instance.
+     *
+     * @param {issuer}
+     * @type {String} 
+     * @desc maybe it is the Service name
+     *
+     * @param {type}
+     * @type {String} 
+     * @desc type of OTP instance
+     *
+     * @return {String}
+     */
+    url_gen(issuer, type) {
+        return `otpauth://${type}/SK?secret=${this.secret}&issuer=${issuer}`;
+    }
  }
 

src/totp.js

@@ -81,4 +81,17 @@ export class TOTP extends OTP {
             return false;
         }
     }
+
+    /*＊
+     * Generate a url with TOTP instance.
+     *
+     * @param {issuer}
+     * @type {String} 
+     * @desc maybe it is the Service name
+     *
+     * @return {String}
+     */
+    url_gen(issuer="") {
+        return super.url_gen(issuer, "totp");
+    }
  }