Regular expression to validate image - regex

I am writing a web application in golang. I am using regular expression to validate the URL. But I am not able to validate image (abc.png) in the URL validation.
var validPath = regexp.MustCompile("^/$|/(home|about|badge)/(|[a-zA-Z0-9]+)$")
The above URL takes /home/, /about/ but could not make for /abc.png. I mean . itself not working
I tried the following regex, but it didn't help
var validPath = regexp.MustCompile("^/$|/(home|about|badge|.)/(|[a-zA-Z0-9]+)$")
var validPath = regexp.MustCompile("^/$|/(home|about|badge)(/|.)(|[a-zA-Z0-9]+)$")
And I am trying to match http://localhost:8080/badge.png
Could anyone please help me on this?

It appears
^/$|^(?:/(home|about|badge))?/((?:badge|abc)\.png|[a-zA-Z0-9]*)$
should work for you. See the regex demo.
The pattern breakdown:
^/$ - a / as a whole string
| - or...
^ - start of string
(?:/(home|about|badge))? - optional sequence of / + either home, or about or badge
/ - a / symbol followed with
((?:badge|abc)\.png|[a-zA-Z0-9]*) - Group 1 capturing:
(?:badge|abc)\.png - badge or abc followed with .png
| - or...
[a-zA-Z0-9]* - zero or more alphanumerics
$ - end of string
And here is the Go playground demo.
package main
import "fmt"
import "regexp"
func main() {
//var validPath = regexp.MustCompile("^/((home|about)(/[a-zA-Z0-9]*)?|[a-zA-Z0-9]+\\.[a-z]+)?$")
var validPath = regexp.MustCompile(`^/$|^(?:/(home|about|badge))?/((?:badge|abc)\.png|[a-zA-Z0-9]*)$`)
fmt.Println(validPath.MatchString("/"), validPath.MatchString("/home/"), validPath.MatchString("/about/"), validPath.MatchString("/home/13jia0"), validPath.MatchString("/about/1jnmjan"), validPath.MatchString("/badge.png"), validPath.MatchString("/abc.png"))
fmt.Println(validPath.MatchString("/nope/"), validPath.MatchString("/invalid.png"), validPath.MatchString("/test/test"))
m := validPath.FindStringSubmatch("/about/global")
fmt.Println("validate() :: URL validation path m[1] : ", m[1])
fmt.Println("validate() :: URL validation path m[2] : ", m[2])
if m == nil || m[2] != "global" {
fmt.Println("Not valid")
}
}

What you are looking for is the following (based off the example paths you posted):
var validPath = regexp.MustCompile("^/((home|about)(/[a-zA-Z0-9]*)?|[a-zA-Z0-9]+\\.[a-z]+)?$")
Playground with examples

You can validate with the following Regex:
var validPath = regexp.MustCompile("^\/(home|about|badge)\/[a-zA-Z0-9]+[.][a-z]+$")
Ps: I made a flexible Regex, so it accepts a lot of formats of images: png, jpg, jpeg and so on..
You can test it here: Regex

Related

remove "?show=false" using regex [duplicate]

I looking for regular expression to use in my javascript code, which give me last part of url without parameters if they exists - here is example - with and without parameters:
https://scontent-fra3-1.xx.fbcdn.net/v/t1.0-9/14238253_132683573850463_7287992614234853254_n.jpg?oh=fdbf6800f33876a86ed17835cfce8e3b&oe=599548AC
https://scontent-fra3-1.xx.fbcdn.net/v/t1.0-9/14238253_132683573850463_7287992614234853254_n.jpg
In both cases as result I want to get:
14238253_132683573850463_7287992614234853254_n.jpg
Here is this regexp
.*\/([^?]+)
and JS code:
let lastUrlPart = /.*\/([^?]+)/.exec(url)[1];
let lastUrlPart = url => /.*\/([^?]+)/.exec(url)[1];
// TEST
let t1 = "https://scontent-fra3-1.xx.fbcdn.net/v/t1.0-9/14238253_132683573850463_7287992614234853254_n.jpg?oh=fdbf6800f33876a86ed17835cfce8e3b&oe=599548AC"
let t2 = "https://scontent-fra3-1.xx.fbcdn.net/v/t1.0-9/14238253_132683573850463_7287992614234853254_n.jpg"
console.log(lastUrlPart(t1));
console.log(lastUrlPart(t2));
May be there are better alternatives?
You could always try doing it without regex. Split the URL by "/" and then parse out the last part of the URL.
var urlPart = url.split("/");
var img = urlPart[urlPart.length-1].split("?")[0];
That should get everything after the last "/" and before the first "?".

Validating Youtube Playlist URL using Regex

How to validate a youtube playlist url using regex?
I've found the answer for validating video from other question..
/^http:\/\/(?:www\.)?youtube.com\/watch\?(?=.*v=\w+)(?:\S+)?$/
But I've just unable to validate a url like this :
http://www.youtube.com/watch?list=PL1F9CA2A03CF286C2&v=pFS4zYWxzNA&
or
http://www.youtube.com/watch?v=pFS4zYWxzNA&list=PL1F9CA2A03CF286C2&
I ended up with a something similar but different:
/^.*(youtu.be\/|list=)([^#\&\?]*).*/
worked against the following urls:
https://www.youtube.com/watch?v=4jduuQh-Uho&list=PLBOh8f9FoHHjOz0vGrD20WcTtJar-LOrw&index=3
https://www.youtube.com/playlist?list=PLBOh8f9FoHHjOz0vGrD20WcTtJar-LOrw
Given the follow code:
var regExp = /^.*(youtu.be\/|list=)([^#\&\?]*).*/;
var match = url.match(regExp);
if (match && match[2]){
return match[2];
}
return null;
My return is PLBOh8f9FoHHjOz0vGrD20WcTtJar-LOrw
try this
^(https|http):\/\/(?:www\.)?youtube\.com\/watch\? #you forgot to mask the dot before com
( #may lead to wrong parsing
(v=.*&list=.*)| #v and then list
(list=.*&v=.*) #or versa verse - feel free to use better matching
) #for ids like "pFS4zYWxzNA"
(&.*)*$ #all other kinds of parameter
Edit:
i improved the matching
^(https|http):\/\/(?:www\.)?youtube\.com\/watch\?
(?:&.*)* #extra params at the beginning
(
(?:
v=([a-zA-Z0-9_\-]{11}) #propper mathing for id
(?:&.*)* #extras
&list=([a-zA-Z0-9_\-]{18}) #list
)
|
(?:
list=([a-zA-Z0-9_\-]{18})
(?:&.*)* #versa
&v=([a-zA-Z0-9_\-]{11})
)
)
(?:&.*)* #extras at the end
(?:\#.*)*$ #anchors
First validate YouTube url:
^https?\:\/\/(?:www\.youtube(?:\-nocookie)?\.com\/|m\.youtube\.com\/|youtube\.com\/)?(?:ytscreeningroom\?vi?=|youtu\.be\/|vi?\/|user\/.+\/u\/\w{1,2}\/|embed\/|watch\?(?:.*\&)?vi?=|\&vi?=|\?(?:.*\&)?vi?=)([^#\&\?\n\/<>\"']*)
then find the list:
[\?|&](list=)(.*)\&
I ended up with a something similar but different:
/[?&]list=([^#?&]*)/
worked against the following urls:
https://www.youtube.com/watch?v=HpqrKeD6ZTc&list=PLC18xlbCdwtTc61wuDviNoKmNUAVFT50D
https://www.youtube.com/playlist?list=PLC18xlbCdwtTc61wuDviNoKmNUAVFT50D
Given the follow code:
const listID = url.match(/[?&]list=([^#?&]*)/)?.[1];
console.log(listID);
My return is PLC18xlbCdwtTc61wuDviNoKmNUAVFT50D

Regex to replace domain within links that are not images

Need to replace a domain name on all the links on the page that are not images or pdf files.
This would be a full html page received through a proxy service.
Example:
test<img src="http://www.test.com" /><a href="http://www.test.com/test.pdf">pdf
test1
Result:
test<img src="http://www.test.com" /><a href="http://www.test.com/test.pdf">pdf
test1
If you are using .NET, I strongly suggest you to use HTML Agility Pack
Direct parsing using regex can be very error prone. This questions is also similar to the post below.
What regex should I use to remove links from HTML code in C#?
If the domain is http://www.example.com, the following should do the trick:
/http:\/\/www\.example\.com\S*(?!pdf|jpg|png|gif)\s/
This uses a negative lookahead to ensure that the regex matches a string only if the string does not contain pdf,png,jpg or gif at the specified position.
If none of your pdf urls have query parameters (like a.pdf?asd=12), the following code will work. It replaces only absolute and root-relative urls.
var links = document.getElementsByTagName("a");
var len = links.length;
var newDomain = "http://mydomain.com";
/**
* Match absolute urls (starting with http)
* and root relative urls (starting with a `/`)
* Does not match relative urls like "subfolder/anotherpage.html"
* */
var regex = new RegExp("^(?:https?://[^/]+)?(/.*)$", "i");
//uncomment next line if you want to replace only absolute urls
//regex = new RegExp("^https?://[^/]+(/.*)$", "i");
for(var i = 0; i < len; i++)
{
var link = links.item(i);
var href = link.getAttribute("href");
if(!href) //in case of named anchors
continue;
if(href.match(/\.pdf$/i)) //if pdf
continue;
href = href.replace(regex, newDomain + "$1");
link.setAttribute("href", href);
}

How do I linkify text using ActionScript 3

I have a text that I want to linkify (identify URLs and convert them to HTML links). The text could be multi-line, and could contain multiple urls like the example below.
My current actionscript code looks like this
<mx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.rpc.events.FaultEvent;
import mx.rpc.events.ResultEvent;
private function init():void {
var str:String = "#stack the website for google is http://www.google.com and gmail is http://gmail.com";
//Alert.show(linkify(str),"Error");
txtStatus.htmlText = linkify(str);
}
private function linkify(texty:String):String {
//return texty.replace("/[A-Za-z]+:\/\/[A-Za-z0-9-_]+\.[A-Za-z0-9-_:%&\?\/.=]+/g",function(m):String { return m.linkify(m);});
//return texty.replace(/[A-Za-z]+:\/\/[A-Za-z0-9-_]+\.[A-Za-z0-9-_:%&\?\/.=]+/g, function(m):String {return m.linkify(m);}).replace(/(^|[^\w])(#[\d\w\-]+)/g, function(m2):String{return '#' + m2.substr(1) + ''; });
var pattern:RegExp = /[A-Za-z]+:\/\/[A-Za-z0-9-_]+\.[A-Za-z0-9-_:%&\?\/.=]+/g;
var match:String = pattern.exec(texty);
return texty.replace(pattern,'<a href="' + match + '">' +
match + '</a>');
}
]]>
</mx:Script>
The problem with the above script is that it recognizes the first match and uses that across. Also how do i do it for #?
Any help is highly appreciated.
ooph ... why does everybody use regex these days, to accomplish super simple tasks? also, you forgot, that "+" is a valid character for URLs, as a replacement for space, and even an awful lot of other characters may be used, so your pattern would not even match accordingly ...
well, anyway, have a look at AS3 regex metacharacters ...
that'll GREATLY improve your expression's readability and is much more robust...
i'd go with something like this, really:
var r:RegExp = /(?:http|https):\/\/\S*/g;
trace(str.replace(r, function (s:String,...rest):String {
return '' + s + ''
} ));
but the actual point, was the global flag ...
good luck then ... :)
greetz
back2dos

Getting parts of a URL (Regex)

Given the URL (single line):
http://test.example.com/dir/subdir/file.html
How can I extract the following parts using regular expressions:
The Subdomain (test)
The Domain (example.com)
The path without the file (/dir/subdir/)
The file (file.html)
The path with the file (/dir/subdir/file.html)
The URL without the path (http://test.example.com)
(add any other that you think would be useful)
The regex should work correctly even if I enter the following URL:
http://example.example.com/example/example/example.html
A single regex to parse and breakup a
full URL including query parameters
and anchors e.g.
https://www.google.com/dir/1/2/search.html?arg=0-a&arg1=1-b&arg3-c#hash
^((http[s]?|ftp):\/)?\/?([^:\/\s]+)((\/\w+)*\/)([\w\-\.]+[^#?\s]+)(.*)?(#[\w\-]+)?$
RexEx positions:
url: RegExp['$&'],
protocol:RegExp.$2,
host:RegExp.$3,
path:RegExp.$4,
file:RegExp.$6,
query:RegExp.$7,
hash:RegExp.$8
you could then further parse the host ('.' delimited) quite easily.
What I would do is use something like this:
/*
^(.*:)//([A-Za-z0-9\-\.]+)(:[0-9]+)?(.*)$
*/
proto $1
host $2
port $3
the-rest $4
the further parse 'the rest' to be as specific as possible. Doing it in one regex is, well, a bit crazy.
I'm a few years late to the party, but I'm surprised no one has mentioned the Uniform Resource Identifier specification has a section on parsing URIs with a regular expression. The regular expression, written by Berners-Lee, et al., is:
^(([^:/?#]+):)?(//([^/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?
12 3 4 5 6 7 8 9
The numbers in the second line above are only to assist readability;
they indicate the reference points for each subexpression (i.e., each
paired parenthesis). We refer to the value matched for subexpression
as $. For example, matching the above expression to
http://www.ics.uci.edu/pub/ietf/uri/#Related
results in the following subexpression matches:
$1 = http:
$2 = http
$3 = //www.ics.uci.edu
$4 = www.ics.uci.edu
$5 = /pub/ietf/uri/
$6 = <undefined>
$7 = <undefined>
$8 = #Related
$9 = Related
For what it's worth, I found that I had to escape the forward slashes in JavaScript:
^(([^:\/?#]+):)?(\/\/([^\/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?
I realize I'm late to the party, but there is a simple way to let the browser parse a url for you without a regex:
var a = document.createElement('a');
a.href = 'http://www.example.com:123/foo/bar.html?fox=trot#foo';
['href','protocol','host','hostname','port','pathname','search','hash'].forEach(function(k) {
console.log(k+':', a[k]);
});
/*//Output:
href: http://www.example.com:123/foo/bar.html?fox=trot#foo
protocol: http:
host: www.example.com:123
hostname: www.example.com
port: 123
pathname: /foo/bar.html
search: ?fox=trot
hash: #foo
*/
I found the highest voted answer (hometoast's answer) doesn't work perfectly for me. Two problems:
It can not handle port number.
The hash part is broken.
The following is a modified version:
^((http[s]?|ftp):\/)?\/?([^:\/\s]+)(:([^\/]*))?((\/\w+)*\/)([\w\-\.]+[^#?\s]+)(\?([^#]*))?(#(.*))?$
Position of parts are as follows:
int SCHEMA = 2, DOMAIN = 3, PORT = 5, PATH = 6, FILE = 8, QUERYSTRING = 9, HASH = 12
Edit posted by anon user:
function getFileName(path) {
return path.match(/^((http[s]?|ftp):\/)?\/?([^:\/\s]+)(:([^\/]*))?((\/[\w\/-]+)*\/)([\w\-\.]+[^#?\s]+)(\?([^#]*))?(#(.*))?$/i)[8];
}
I needed a regular Expression to match all urls and made this one:
/(?:([^\:]*)\:\/\/)?(?:([^\:\#]*)(?:\:([^\#]*))?\#)?(?:([^\/\:]*)\.(?=[^\.\/\:]*\.[^\.\/\:]*))?([^\.\/\:]*)(?:\.([^\/\.\:]*))?(?:\:([0-9]*))?(\/[^\?#]*(?=.*?\/)\/)?([^\?#]*)?(?:\?([^#]*))?(?:#(.*))?/
It matches all urls, any protocol, even urls like
ftp://user:pass#www.cs.server.com:8080/dir1/dir2/file.php?param1=value1#hashtag
The result (in JavaScript) looks like this:
["ftp", "user", "pass", "www.cs", "server", "com", "8080", "/dir1/dir2/", "file.php", "param1=value1", "hashtag"]
An url like
mailto://admin#www.cs.server.com
looks like this:
["mailto", "admin", undefined, "www.cs", "server", "com", undefined, undefined, undefined, undefined, undefined]
I was trying to solve this in javascript, which should be handled by:
var url = new URL('http://a:b#example.com:890/path/wah#t/foo.js?foo=bar&bingobang=&king=kong#kong.com#foobar/bing/bo#ng?bang');
since (in Chrome, at least) it parses to:
{
"hash": "#foobar/bing/bo#ng?bang",
"search": "?foo=bar&bingobang=&king=kong#kong.com",
"pathname": "/path/wah#t/foo.js",
"port": "890",
"hostname": "example.com",
"host": "example.com:890",
"password": "b",
"username": "a",
"protocol": "http:",
"origin": "http://example.com:890",
"href": "http://a:b#example.com:890/path/wah#t/foo.js?foo=bar&bingobang=&king=kong#kong.com#foobar/bing/bo#ng?bang"
}
However, this isn't cross browser (https://developer.mozilla.org/en-US/docs/Web/API/URL), so I cobbled this together to pull the same parts out as above:
^(?:(?:(([^:\/#\?]+:)?(?:(?:\/\/)(?:(?:(?:([^:#\/#\?]+)(?:\:([^:#\/#\?]*))?)#)?(([^:\/#\?\]\[]+|\[[^\/\]##?]+\])(?:\:([0-9]+))?))?)?)?((?:\/?(?:[^\/\?#]+\/+)*)(?:[^\?#]*)))?(\?[^#]+)?)(#.*)?
Credit for this regex goes to https://gist.github.com/rpflorence who posted this jsperf http://jsperf.com/url-parsing (originally found here: https://gist.github.com/jlong/2428561#comment-310066) who came up with the regex this was originally based on.
The parts are in this order:
var keys = [
"href", // http://user:pass#host.com:81/directory/file.ext?query=1#anchor
"origin", // http://user:pass#host.com:81
"protocol", // http:
"username", // user
"password", // pass
"host", // host.com:81
"hostname", // host.com
"port", // 81
"pathname", // /directory/file.ext
"search", // ?query=1
"hash" // #anchor
];
There is also a small library which wraps it and provides query params:
https://github.com/sadams/lite-url (also available on bower)
If you have an improvement, please create a pull request with more tests and I will accept and merge with thanks.
Propose a much more readable solution (in Python, but applies to any regex):
def url_path_to_dict(path):
pattern = (r'^'
r'((?P<schema>.+?)://)?'
r'((?P<user>.+?)(:(?P<password>.*?))?#)?'
r'(?P<host>.*?)'
r'(:(?P<port>\d+?))?'
r'(?P<path>/.*?)?'
r'(?P<query>[?].*?)?'
r'$'
)
regex = re.compile(pattern)
m = regex.match(path)
d = m.groupdict() if m is not None else None
return d
def main():
print url_path_to_dict('http://example.example.com/example/example/example.html')
Prints:
{
'host': 'example.example.com',
'user': None,
'path': '/example/example/example.html',
'query': None,
'password': None,
'port': None,
'schema': 'http'
}
subdomain and domain are difficult because the subdomain can have several parts, as can the top level domain, http://sub1.sub2.domain.co.uk/
the path without the file : http://[^/]+/((?:[^/]+/)*(?:[^/]+$)?)
the file : http://[^/]+/(?:[^/]+/)*((?:[^/.]+\.)+[^/.]+)$
the path with the file : http://[^/]+/(.*)
the URL without the path : (http://[^/]+/)
(Markdown isn't very friendly to regexes)
This improved version should work as reliably as a parser.
// Applies to URI, not just URL or URN:
// http://en.wikipedia.org/wiki/Uniform_Resource_Identifier#Relationship_to_URL_and_URN
//
// http://labs.apache.org/webarch/uri/rfc/rfc3986.html#regexp
//
// (?:([^:/?#]+):)?(?://([^/?#]*))?([^?#]*)(?:\?([^#]*))?(?:#(.*))?
//
// http://en.wikipedia.org/wiki/URI_scheme#Generic_syntax
//
// $# matches the entire uri
// $1 matches scheme (ftp, http, mailto, mshelp, ymsgr, etc)
// $2 matches authority (host, user:pwd#host, etc)
// $3 matches path
// $4 matches query (http GET REST api, etc)
// $5 matches fragment (html anchor, etc)
//
// Match specific schemes, non-optional authority, disallow white-space so can delimit in text, and allow 'www.' w/o scheme
// Note the schemes must match ^[^\s|:/?#]+(?:\|[^\s|:/?#]+)*$
//
// (?:()(www\.[^\s/?#]+\.[^\s/?#]+)|(schemes)://([^\s/?#]*))([^\s?#]*)(?:\?([^\s#]*))?(#(\S*))?
//
// Validate the authority with an orthogonal RegExp, so the RegExp above won’t fail to match any valid urls.
function uriRegExp( flags, schemes/* = null*/, noSubMatches/* = false*/ )
{
if( !schemes )
schemes = '[^\\s:\/?#]+'
else if( !RegExp( /^[^\s|:\/?#]+(?:\|[^\s|:\/?#]+)*$/ ).test( schemes ) )
throw TypeError( 'expected URI schemes' )
return noSubMatches ? new RegExp( '(?:www\\.[^\\s/?#]+\\.[^\\s/?#]+|' + schemes + '://[^\\s/?#]*)[^\\s?#]*(?:\\?[^\\s#]*)?(?:#\\S*)?', flags ) :
new RegExp( '(?:()(www\\.[^\\s/?#]+\\.[^\\s/?#]+)|(' + schemes + ')://([^\\s/?#]*))([^\\s?#]*)(?:\\?([^\\s#]*))?(?:#(\\S*))?', flags )
}
// http://en.wikipedia.org/wiki/URI_scheme#Official_IANA-registered_schemes
function uriSchemesRegExp()
{
return 'about|callto|ftp|gtalk|http|https|irc|ircs|javascript|mailto|mshelp|sftp|ssh|steam|tel|view-source|ymsgr'
}
const URI_RE = /^(([^:\/\s]+):\/?\/?([^\/\s#]*#)?([^\/#:]*)?:?(\d+)?)?(\/[^?]*)?(\?([^#]*))?(#[\s\S]*)?$/;
/**
* GROUP 1 ([scheme][authority][host][port])
* GROUP 2 (scheme)
* GROUP 3 (authority)
* GROUP 4 (host)
* GROUP 5 (port)
* GROUP 6 (path)
* GROUP 7 (?query)
* GROUP 8 (query)
* GROUP 9 (fragment)
*/
URI_RE.exec("https://john:doe#www.example.com:123/forum/questions/?tag=networking&order=newest#top");
URI_RE.exec("/forum/questions/?tag=networking&order=newest#top");
URI_RE.exec("ldap://[2001:db8::7]/c=GB?objectClass?one");
URI_RE.exec("mailto:John.Doe#example.com");
Above you can find javascript implementation with modified regex
Try the following:
^((ht|f)tp(s?)\:\/\/|~/|/)?([\w]+:\w+#)?([a-zA-Z]{1}([\w\-]+\.)+([\w]{2,5}))(:[\d]{1,5})?((/?\w+/)+|/?)(\w+\.[\w]{3,4})?((\?\w+=\w+)?(&\w+=\w+)*)?
It supports HTTP / FTP, subdomains, folders, files etc.
I found it from a quick google search:
Link
/^((?P<scheme>https?|ftp):\/)?\/?((?P<username>.*?)(:(?P<password>.*?)|)#)?(?P<hostname>[^:\/\s]+)(?P<port>:([^\/]*))?(?P<path>(\/\w+)*\/)(?P<filename>[-\w.]+[^#?\s]*)?(?P<query>\?([^#]*))?(?P<fragment>#(.*))?$/
From my answer on a similar question. Works better than some of the others mentioned because they had some bugs (such as not supporting username/password, not supporting single-character filenames, fragment identifiers being broken).
You can get all the http/https, host, port, path as well as query by using Uri object in .NET.
just the difficult task is to break the host into sub domain, domain name and TLD.
There is no standard to do so and can't be simply use string parsing or RegEx to produce the correct result. At first, I am using RegEx function but not all URL can be parse the subdomain correctly. The practice way is to use a list of TLDs. After a TLD for a URL is defined the left part is domain and the remaining is sub domain.
However the list need to maintain it since new TLDs is possible. The current moment I know is publicsuffix.org maintain the latest list and you can use domainname-parser tools from google code to parse the public suffix list and get the sub domain, domain and TLD easily by using DomainName object: domainName.SubDomain, domainName.Domain and domainName.TLD.
This answers also helpfull:
Get the subdomain from a URL
CaLLMeLaNN
Here is one that is complete, and doesnt rely on any protocol.
function getServerURL(url) {
var m = url.match("(^(?:(?:.*?)?//)?[^/?#;]*)");
console.log(m[1]) // Remove this
return m[1];
}
getServerURL("http://dev.test.se")
getServerURL("http://dev.test.se/")
getServerURL("//ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js")
getServerURL("//")
getServerURL("www.dev.test.se/sdas/dsads")
getServerURL("www.dev.test.se/")
getServerURL("www.dev.test.se?abc=32")
getServerURL("www.dev.test.se#abc")
getServerURL("//dev.test.se?sads")
getServerURL("http://www.dev.test.se#321")
getServerURL("http://localhost:8080/sads")
getServerURL("https://localhost:8080?sdsa")
Prints
http://dev.test.se
http://dev.test.se
//ajax.googleapis.com
//
www.dev.test.se
www.dev.test.se
www.dev.test.se
www.dev.test.se
//dev.test.se
http://www.dev.test.se
http://localhost:8080
https://localhost:8080
None of the above worked for me. Here's what I ended up using:
/^(?:((?:https?|s?ftp):)\/\/)([^:\/\s]+)(?::(\d*))?(?:\/([^\s?#]+)?([?][^?#]*)?(#.*)?)?/
I like the regex that was published in "Javascript: The Good Parts".
Its not too short and not too complex.
This page on github also has the JavaScript code that uses it.
But it an be adapted for any language.
https://gist.github.com/voodooGQ/4057330
Java offers a URL class that will do this. Query URL Objects.
On a side note, PHP offers parse_url().
I would recommend not using regex. An API call like WinHttpCrackUrl() is less error prone.
http://msdn.microsoft.com/en-us/library/aa384092%28VS.85%29.aspx
I tried a few of these that didn't cover my needs, especially the highest voted which didn't catch a url without a path (http://example.com/)
also lack of group names made it unusable in ansible (or perhaps my jinja2 skills are lacking).
so this is my version slightly modified with the source being the highest voted version here:
^((?P<protocol>http[s]?|ftp):\/)?\/?(?P<host>[^:\/\s]+)(?P<path>((\/\w+)*\/)([\w\-\.]+[^#?\s]+))*(.*)?(#[\w\-]+)?$
I build this one. Very permissive it's not to check url juste divide it.
^((http[s]?):\/\/)?([a-zA-Z0-9-.]*)?([\/]?[^?#\n]*)?([?]?[^?#\n]*)?([#]?[^?#\n]*)$
match 1 : full protocole with :// (http or https)
match 2 : protocole without ://
match 3 : host
match 4 : slug
match 5 : param
match 6 : anchor
work
http://
https://
www.demo.com
/slug
?foo=bar
#anchor
https://demo.com
https://demo.com/
https://demo.com/slug
https://demo.com/slug/foo
https://demo.com/?foo=bar
https://demo.com/?foo=bar#anchor
https://demo.com/?foo=bar&bar=foo#anchor
https://www.greate-demo.com/
crash
#anchor#
?toto?
I needed some REGEX to parse the components of a URL in Java.
This is what I'm using:
"^(?:(http[s]?|ftp):/)?/?" + // METHOD
"([^:^/^?^#\\s]+)" + // HOSTNAME
"(?::(\\d+))?" + // PORT
"([^?^#.*]+)?" + // PATH
"(\\?[^#.]*)?" + // QUERY
"(#[\\w\\-]+)?$" // ID
Java Code Snippet:
final Pattern pattern = Pattern.compile(
"^(?:(http[s]?|ftp):/)?/?" + // METHOD
"([^:^/^?^#\\s]+)" + // HOSTNAME
"(?::(\\d+))?" + // PORT
"([^?^#.*]+)?" + // PATH
"(\\?[^#.]*)?" + // QUERY
"(#[\\w\\-]+)?$" // ID
);
final Matcher matcher = pattern.matcher(url);
System.out.println(" URL: " + url);
if (matcher.matches())
{
System.out.println(" Method: " + matcher.group(1));
System.out.println("Hostname: " + matcher.group(2));
System.out.println(" Port: " + matcher.group(3));
System.out.println(" Path: " + matcher.group(4));
System.out.println(" Query: " + matcher.group(5));
System.out.println(" ID: " + matcher.group(6));
return matcher.group(2);
}
System.out.println();
System.out.println();
Using http://www.fileformat.info/tool/regex.htm hometoast's regex works great.
But here is the deal, I want to use different regex patterns in different situations in my program.
For example, I have this URL, and I have an enumeration that lists all supported URLs in my program. Each object in the enumeration has a method getRegexPattern that returns the regex pattern which will then be used to compare with a URL. If the particular regex pattern returns true, then I know that this URL is supported by my program. So, each enumeration has it's own regex depending on where it should look inside the URL.
Hometoast's suggestion is great, but in my case, I think it wouldn't help (unless I copy paste the same regex in all enumerations).
That is why I wanted the answer to give the regex for each situation separately. Although +1 for hometoast. ;)
I know you're claiming language-agnostic on this, but can you tell us what you're using just so we know what regex capabilities you have?
If you have the capabilities for non-capturing matches, you can modify hometoast's expression so that subexpressions that you aren't interested in capturing are set up like this:
(?:SOMESTUFF)
You'd still have to copy and paste (and slightly modify) the Regex into multiple places, but this makes sense--you're not just checking to see if the subexpression exists, but rather if it exists as part of a URL. Using the non-capturing modifier for subexpressions can give you what you need and nothing more, which, if I'm reading you correctly, is what you want.
Just as a small, small note, hometoast's expression doesn't need to put brackets around the 's' for 'https', since he only has one character in there. Quantifiers quantify the one character (or character class or subexpression) directly preceding them. So:
https?
would match 'http' or 'https' just fine.
regexp to get the URL path without the file.
url = 'http://domain/dir1/dir2/somefile'
url.scan(/^(http://[^/]+)((?:/[^/]+)+(?=/))?/?(?:[^/]+)?$/i).to_s
It can be useful for adding a relative path to this url.
The regex to do full parsing is quite horrendous. I've included named backreferences for legibility, and broken each part into separate lines, but it still looks like this:
^(?:(?P<protocol>\w+(?=:\/\/))(?::\/\/))?
(?:(?P<host>(?:(?:&(?:amp|apos|gt|lt|nbsp|quot|bull|hellip|[lr][ds]quo|[mn]dash|permil|\#[1-9][0-9]{1,3}|[A-Za-z][0-9A-Za-z]+);)|[^\/?#:]+)(?::(?P<port>[0-9]+))?)\/)?
(?:(?P<path>(?:(?:&(?:amp|apos|gt|lt|nbsp|quot|bull|hellip|[lr][ds]quo|[mn]dash|permil|\#[1-9][0-9]{1,3}|[A-Za-z][0-9A-Za-z]+);)|[^?#])+)\/)?
(?P<file>(?:(?:&(?:amp|apos|gt|lt|nbsp|quot|bull|hellip|[lr][ds]quo|[mn]dash|permil|\#[1-9][0-9]{1,3}|[A-Za-z][0-9A-Za-z]+);)|[^?#])+)
(?:\?(?P<querystring>(?:(?:&(?:amp|apos|gt|lt|nbsp|quot|bull|hellip|[lr][ds]quo|[mn]dash|permil|\#[1-9][0-9]{1,3}|[A-Za-z][0-9A-Za-z]+);)|[^#])+))?
(?:#(?P<fragment>.*))?$
The thing that requires it to be so verbose is that except for the protocol or the port, any of the parts can contain HTML entities, which makes delineation of the fragment quite tricky. So in the last few cases - the host, path, file, querystring, and fragment, we allow either any html entity or any character that isn't a ? or #. The regex for an html entity looks like this:
$htmlentity = "&(?:amp|apos|gt|lt|nbsp|quot|bull|hellip|[lr][ds]quo|[mn]dash|permil|\#[1-9][0-9]{1,3}|[A-Za-z][0-9A-Za-z]+);"
When that is extracted (I used a mustache syntax to represent it), it becomes a bit more legible:
^(?:(?P<protocol>(?:ht|f)tps?|\w+(?=:\/\/))(?::\/\/))?
(?:(?P<host>(?:{{htmlentity}}|[^\/?#:])+(?::(?P<port>[0-9]+))?)\/)?
(?:(?P<path>(?:{{htmlentity}}|[^?#])+)\/)?
(?P<file>(?:{{htmlentity}}|[^?#])+)
(?:\?(?P<querystring>(?:{{htmlentity}};|[^#])+))?
(?:#(?P<fragment>.*))?$
In JavaScript, of course, you can't use named backreferences, so the regex becomes
^(?:(\w+(?=:\/\/))(?::\/\/))?(?:((?:(?:&(?:amp|apos|gt|lt|nbsp|quot|bull|hellip|[lr][ds]quo|[mn]dash|permil|\#[1-9][0-9]{1,3}|[A-Za-z][0-9A-Za-z]+);)|[^\/?#:]+)(?::([0-9]+))?)\/)?(?:((?:(?:&(?:amp|apos|gt|lt|nbsp|quot|bull|hellip|[lr][ds]quo|[mn]dash|permil|\#[1-9][0-9]{1,3}|[A-Za-z][0-9A-Za-z]+);)|[^?#])+)\/)?((?:(?:&(?:amp|apos|gt|lt|nbsp|quot|bull|hellip|[lr][ds]quo|[mn]dash|permil|\#[1-9][0-9]{1,3}|[A-Za-z][0-9A-Za-z]+);)|[^?#])+)(?:\?((?:(?:&(?:amp|apos|gt|lt|nbsp|quot|bull|hellip|[lr][ds]quo|[mn]dash|permil|\#[1-9][0-9]{1,3}|[A-Za-z][0-9A-Za-z]+);)|[^#])+))?(?:#(.*))?$
and in each match, the protocol is \1, the host is \2, the port is \3, the path \4, the file \5, the querystring \6, and the fragment \7.
//USING REGEX
/**
* Parse URL to get information
*
* #param url the URL string to parse
* #return parsed the URL parsed or null
*/
var UrlParser = function (url) {
"use strict";
var regx = /^(((([^:\/#\?]+:)?(?:(\/\/)((?:(([^:#\/#\?]+)(?:\:([^:#\/#\?]+))?)#)?(([^:\/#\?\]\[]+|\[[^\/\]##?]+\])(?:\:([0-9]+))?))?)?)?((\/?(?:[^\/\?#]+\/+)*)([^\?#]*)))?(\?[^#]+)?)(#.*)?/,
matches = regx.exec(url),
parser = null;
if (null !== matches) {
parser = {
href : matches[0],
withoutHash : matches[1],
url : matches[2],
origin : matches[3],
protocol : matches[4],
protocolseparator : matches[5],
credhost : matches[6],
cred : matches[7],
user : matches[8],
pass : matches[9],
host : matches[10],
hostname : matches[11],
port : matches[12],
pathname : matches[13],
segment1 : matches[14],
segment2 : matches[15],
search : matches[16],
hash : matches[17]
};
}
return parser;
};
var parsedURL=UrlParser(url);
console.log(parsedURL);
I tried this regex for parsing url partitions:
^((http[s]?|ftp):\/)?\/?([^:\/\s]+)(:([^\/]*))?((\/?(?:[^\/\?#]+\/+)*)([^\?#]*))(\?([^#]*))?(#(.*))?$
URL: https://www.google.com/my/path/sample/asd-dsa/this?key1=value1&key2=value2
Matches:
Group 1. 0-7 https:/
Group 2. 0-5 https
Group 3. 8-22 www.google.com
Group 6. 22-50 /my/path/sample/asd-dsa/this
Group 7. 22-46 /my/path/sample/asd-dsa/
Group 8. 46-50 this
Group 9. 50-74 ?key1=value1&key2=value2
Group 10. 51-74 key1=value1&key2=value2
The best answer suggested here didn't work for me because my URLs also contain a port.
However modifying it to the following regex worked for me:
^((http[s]?|ftp):\/)?\/?([^:\/\s]+)(:\d+)?((\/\w+)*\/)([\w\-\.]+[^#?\s]+)(.*)?(#[\w\-]+)?$
For browser / nodejs environment there is a built in URL class which share the same signature it seems. but check out the respective focus for your case.
https://nodejs.org/api/url.html#urlhost
https://developer.mozilla.org/en-US/docs/Web/API/URL
This is how it may be used though.
let url = new URL('https://test.example.com/cats?name=foofy')
url.protocall; // https:
url.hostname; // test.example.com
url.pathname; // /cats
url.search; // ?name=foofy
let params = url.searchParams
let name = params.get('name');// always string I think so parse accordingly
for more on parameters also see https://developer.mozilla.org/en-US/docs/Web/API/URL/searchParams
String s = "https://www.thomas-bayer.com/axis2/services/BLZService?wsdl";
String regex = "(^http.?://)(.*?)([/\\?]{1,})(.*)";
System.out.println("1: " + s.replaceAll(regex, "$1"));
System.out.println("2: " + s.replaceAll(regex, "$2"));
System.out.println("3: " + s.replaceAll(regex, "$3"));
System.out.println("4: " + s.replaceAll(regex, "$4"));
Will provide the following output:
1: https://
2: www.thomas-bayer.com
3: /
4: axis2/services/BLZService?wsdl
If you change the URL to
String s = "https://www.thomas-bayer.com?wsdl=qwerwer&ttt=888";
the output will be the following :
1: https://
2: www.thomas-bayer.com
3: ?
4: wsdl=qwerwer&ttt=888
enjoy..
Yosi Lev