Getting parts of a URL (Regex)

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 found the highest voted answer (hometoast's answer) doesn't work perfectly for me. Two problems:

1. It can not handle port number.
2. 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];
}

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)

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

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

/^((?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).

Java offers a URL class that will do this. Query URL Objects.

On a side note, PHP offers parse_url().

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.

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