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");
+    }
  }

test/hotp_test.js

@@ -17,5 +17,11 @@ describe('HOTP module test', function() {
             assert.equal(true, a.verify(a.at(0), 0));
             assert.equal(false, a.verify(a.at(0), 1));
         })
+    });
+
+    describe('url_gen() function', function() {
+        it("should return string", function() {
+            assert.equal("string", typeof(a.url_gen()));
+        })
     })
 });

test/totp_test.js

@@ -16,5 +16,11 @@ describe('TOTP module test', function() {
         it("should verify the digit", function() {
             assert.equal(true, a.verify(a.now()));
         })
+    });
+
+    describe('url_gen() function', function() {
+        it("should return string", function() {
+            assert.equal("string", typeof(a.url_gen()));
+        })
     })
 });