Exclude default ports 80/443 from base URL

Fix #59.

oauth-1.0a.js

@@ -194,7 +194,18 @@ OAuth.prototype.getSigningKey = function(token_secret) {
  * @return {String}
  */
 OAuth.prototype.getBaseUrl = function(url) {
-    return url.split('?')[0];
+    var parsed = this.parseUrl(url);
+    var port = parsed.port;
+    var protocol = parsed.protocol.toLowerCase();
+
+    if (
+        (port === ':80' && protocol === 'http') ||
+        (port === ':443' && protocol === 'https')
+    ) {
+        return parsed.protocol + '://' + parsed.hostname + parsed.pathname;
+    }
+
+    return parsed.protocol + '://' + parsed.hostname + parsed.port + parsed.pathname;
 };
 
 /**
@@ -245,6 +256,28 @@ OAuth.prototype.deParamUrl = function(url) {
     return this.deParam(tmp[1]);
 };
 
+Object.defineProperty(OAuth, 'urlPattern', {
+    value: /^(https?):\/\/([^:/?#]+)(\:\d+)?(\/[^?#]*)?(\?[^#]*)?(#.*)?$/
+});
+
+OAuth.prototype.parseUrl = function(url) {
+    var match = OAuth.urlPattern.exec(url);
+    var components;
+
+    if (match == null || match.len < 7) {
+        throw new Error('Invalid URL: "' + url + '".');
+    }
+
+    return {
+        protocol: match[1],
+        hostname: match[2],
+        port: match[3] || '',
+        pathname: match[4] || '',
+        search: match[5] || '',
+        hash: match[6] || ''
+    };
+}
+
 /**
  * Percent Encode
  * @param  {String} str

test/getBaseUrl.js

@@ -0,0 +1,33 @@
+var expect = require('chai').expect;
+var OAuth = require('../oauth-1.0a');
+
+describe('#getBaseUrl', function() {
+	var oauth = new OAuth({
+		consumer: {}
+	});
+
+	beforeEach(function () {
+		oauth = new OAuth({
+			consumer: {}
+		});
+  });
+
+  it('should return base url', function () {
+    expect(oauth.getBaseUrl('http://example.com/path/')).to.equal('http://example.com/path/');
+    expect(oauth.getBaseUrl('http://example.com/path/?foo=bar')).to.equal('http://example.com/path/');
+  });
+
+  it('should exclude default port number', function () {
+    expect(oauth.getBaseUrl('http://example.com/')).to.equal('http://example.com/');
+    expect(oauth.getBaseUrl('http://example.com:80/')).to.equal('http://example.com/');
+    expect(oauth.getBaseUrl('https://example.com/')).to.equal('https://example.com/');
+    expect(oauth.getBaseUrl('https://example.com:443/')).to.equal('https://example.com/');
+  });
+
+  it('should include non-default port number', function () {
+    expect(oauth.getBaseUrl('http://example.com:8080/')).to.equal('http://example.com:8080/');
+    expect(oauth.getBaseUrl('http://example.com:443/')).to.equal('http://example.com:443/');
+    expect(oauth.getBaseUrl('https://example.com:8080/')).to.equal('https://example.com:8080/');
+    expect(oauth.getBaseUrl('https://example.com:80/')).to.equal('https://example.com:80/');
+  });
+});