I'm trying to write a rule to match on a top level domain followed by five digits. My problem arises because my existing pcre is matching on what I have described but much later in the URL then when I want it to. I want it to match on the first occurence of a TLD, not anywhere else. The easy way to check for this is to match on the TLD when it has not bee preceeded at some point by the "/" character. I tried using negative-lookbehind but that doesn't work because that only looks back one single character.
e.g.: How it is currently working
domain.net/stuff/stuff=www.google.com/12345
matches .com/12345 even though I do not want this match because it is not the first TLD in the URL
e.g.: How I want it to work
domain.net/12345/stuff=www.google.com/12345
matches on .net/12345 and ignores the later match on .com/12345
My current expression
(\.[a-z]{2,4})/\d{5}
EDIT: rewrote it so perhaps the problem is clearer in case anyone in the future has this same issue.
You're pretty close :)
You just need to be sure that before matching what you're looking for (i.e: (\.[a-z]{2,4})/\d{5}), you haven't met any / since the beginning of the line.
I would suggest you to simply preppend ^[^\/]*\. before your current regex.
Thus, the resulting regex would be:
^[^\/]*\.([a-z]{2,4})/\d{5}
How does it work?
^ asserts that this is the beginning of the tested String
[^\/]* accepts any sequence of characters that doesn't contain /
\.([a-z]{2,4})/\d{5} is the pattern you want to match (a . followed by 2 to 4 lowercase characters, then a / and at least 5 digits).
Here is a permalink to a working example on regex101.
Cheers!
You can use this regex:
'|^(\w+://)?([\w-]+\.)+\w+/\d{5}|'
Online Demo: http://regex101.com/
Related
I have the following string:
https://www.google.com/today/sunday/abcde2.hopeho.3345GETD?weatherType=RAOM&...
https://www.google.com/today/monday/jbkwe3.ho4eho.8495GETD?weatherType=WHTDSG&...
I'd like to extract jbkwe3.ho4eho.8495GETD or abcde2.hopeho.3345GETD. Anything between the {weekday}/ and the ?weatherType=.
I've tried (?<=sunday\/)$.*?(?=\?weatherType=) but it only works for the first line and I want to make it applicable to all strings regardless the value of {weekday}.
I tried (?<=\/.*\/)$.*?(?=\?weatherType=) but it didn't work. Could anyone familiar with Regex can lend some help? Thank you!
[Update]
I'm new to regex but I was experimenting it on sublime text editor via the "find" functionality which I think should be PCRE (according to this post)
Try this regex:
(?:sun|mon|tues|wednes|thurs|fri|satur)day\/\K[^?]+(?=\?weatherType)
Click for Demo
Link to Code
Explanation:
(?:sun|mon|tues|wednes|thurs|fri|satur)day - matches the day of a week i.e, sunday,monday,tuesday,wednesday,thursday,friday,saturday
\/ - matches /
\K - unmatches whatever has been matched so far and pretends that the match starts from the current position. This can be used for the PCRE.
[^?]+ - matches 1 or more occurences of any character that is not a ?
(?=\?weatherType) - the above subpattern[^?]+ will match all characters that are not ? until it reaches a position which is immediately followed by a ? followed by weatherType
To make the match case-insensitive, you can prepend the regex with (?i) as shown here
In the examples given, you actually only need to grab the characters between the last forward slash ("/") and the first question mark ("?").
You didn't mention what flavor regex (ie, PCRE, grep, Oracle, etc) you're using, and the actual syntax will vary depending on this, but in general, something like the following (Perl) replacement regex would handle the examples given:
s/.*\/([^?]*)\?.*/$1/gm
There are other (and more efficient) ways, but this will do the job.
I am in the process of learning Regex and have been stuck on this case. I have a url that can be in two states EXAMPLE 1:
spotify.com/track/1HYcYZCOpaLjg51qUg8ilA?si=Nf5w1q9MTKu3zG_CJ83RWA
OR EXAMPLE 2:
spotify.com/track/1HYcYZCOpaLjg51qUg8ilA
I need to extract the 1HYcYZCOpaLjg51qUg8ilA ID
So far I am using this: (?<=track\/)(.*)(?=\?)? which works well for Example 2 but it includes the ?si=Nf5w1q9MTKu3zG_CJ83RWA when matching with Example 1.
BUT if I remove the ? at the end of the expression then it works for Example 1 but not Example 2! Doesn't that mean that last group (?=\?) is optional and should match?
Where am I going wrong?
Thanks!
I searched a handful of "Questions that may already have your answer" suggestions from SO, and didn't find this case, so I hope asking this is okay!
The capturing group in your regular expression is trying to match anything (.) as much as possible due to the greediness of the quantifier (*).
When you use:
(?<=track\/)(.*)(?=\?)
only 1HYcYZCOpaLjg51qUg8ilA from the first example is captured, as there is no question mark in your second example.
When using:
(?<=track\/)(.*)(?=\??)
You are effectively making the positive lookahead optional, so the capturing group will try to match as much as possible (including the question mark), so that 1HYcYZCOpaLjg51qUg8ilA?si=Nf5w1q9MTKu3zG_CJ83RWA and 1HYcYZCOpaLjg51qUg8ilA are matched, which is not the desired output.
Rather than matching anything, it is perhaps more appropriate for you to match alphanumerical characters \w only.
(?<=track\/)(\w*)(?=\??)
Alternatively, if you are expecting other characters , let's say a hyphen - or a underscore _, you may use a character class.
(?<=track\/)([a-zA-Z0-9_-]*)(?=\??)
Or you might want to capture everything except a question mark ? with a negated character class.
(?<=track\/)([^?]*)(?=\??)
As pointed out by gaganso, a look-behind is not necessary in this situation (or indeed the lookahead), however it is indeed a good idea to start playing around with them. The look-around assertions do not actually consume the characters in the string. As you can see here, the full match for both matches only consists of what is captured by the capture group. You may find more information here.
This should work:
track\/(\w+)
Please see here.
Since track is part of both the strings, and the ID is formed from alphanumeric characters, the above regex which matches the string "track/" and captures the alphanumeric characters after that string, should provide the required ID.
Regex : (\w+(?=\?))|(\w+&)
See the demo for the regex, https://regexr.com/3s4gv .
This will first try to search for word which has '?' just after it and if thats unsuccessful it will fetch the last word.
I am trying to regex the following string:
https://www.amazon.com/Tapps-Top-Apps-and-Games/dp/B00VU2BZRO/ref=sr_1_3?ie=UTF8&qid=1527813329&sr=8-3&keywords=poop
I want only B00VU2BZRO.
This substring is always going to be a 10 characters, alphanumeric, preceded by dp/.
So far I have the following regex:
[d][p][\/][0-9B][0-9A-Z]{9}
This matches dp/B00VU2BZRO
I want to match only B00VU2BZRO with no dp/
How do I regex this?
Here is one regex option which would produce an exact match of what you want:
(?<=dp\/)(.*)(?=\/)
Demo
Note that this solution makes no assumptions about the length of the path fragment occurring after dp/. If you want to match a certain number of characters, replace (.*) with (.{10}), for example.
Depending on your language/method of application, you have a couple of options.
Positive look behind. This will make your regex more complicated, but will make it match what you want exactly:
(<=dp/)[0-9A-Z]{10}
The construct (<=...) is called a positive look behind. It will not consume any of the string, but will only allow the match to happen if the pattern between the parens is matched.
Capture group. This will make the regex itself slightly simpler, but will add a step to the extraction process:
dp/([0-9A-Z]{10})
Anything between plain parens is a capture group. The entire pattern will be matched, including dp/, but most languages will give you a way of extracting the portion you are interested in.
Depending on your language, you may need to escape the forward slash (/).
As an aside, you never need to create a character class for single characters: [d][p][\/] can equally well be written as just dp\/.
I am struggling with this regex for a while now.
I need to match the text which is in between the <ns3:OutputData> data</ns3:OutputData>.
Note: after nscould be 1 or 2 digits
Note: the data is in one line just as in the example
Note: the ... preceding and ending is just to mention there are more tags nested
My regex so far: (ns\d\d?:OutputData>)\b(.*)(\/\1)
Sample text:
...<ns3:OutputData>foo bar</ns3:OutputData>...
I have tried (?:(ns\d\d?:OutputData>)\b)(.*)(?:(\/\1)) in an attempt to exclude group 1 and 3.
I wan't to exclude the tags which are matched, as in the images:
start
end
Any help is much appreciated.
EDIT
There might be some regex interpretation issue with Grep Console for IntelliJ which I intend to use the regex.
Here is is the latest image with the best match so far...
Your regex is almost there. All you need to do is to make the inside-matcher non-greedy. I.e. instead of (.*) you can write (.*?).
Another, xml-specific alternative is the negated character-class: ([^<]*).
So, this is the regex: (ns\d\d?:OutputData>)\b(.*?)(\/\1) You can experiment with it here.
Update
To make sure that the only group is the one that matches the text, then you have to make it work without backreferences: (?:ns\d\d?:OutputData>)\b(.*?)<
Update 2
It's possible to match only the required parts, using lookbehind. Check the regex here.:
(?<=ns\d:OutputData>)\b([^<]*)|(?<=ns\d\d:OutputData>)\b([^<]*)
Explanation:
The two alternatives are almost identical. The only difference is the number of digits. This is important because some flavors support only fixed-length lookbehinds.
Checking alternative one, we put the starting tag into one lookbehind (?<=...) so it won't be included into the full match.
Then we match every non- lt symbol greedily: [^<]*. This will stop atching at the first closing tag.
Essentially, you need a look behind and a look ahead with a back reference to match just the content, but variable length look behinds are not allowed. Fortunately, you have only 2 variations, so an alternation deals with that:
(?<=<(ns\d:OutputData>)).*?(?=<\/\1)|(?<=<(ns\d\d:OutputData>)).*?(?=<\/\2)
The entire match is the target content between the tags, which may contain anything (including left angle brackets etc).
Note also the reluctant quantifier .*?, so the match stops at the next matching end tag, rather than greedy .* that would match all the way to the last matching end tag.
See live demo.
This was the answer in my case:
(?<=(ns\d:OutputData)>)(.*?)(?=<\/\1)
The answer is based on #WiktorStribiżew 3 given solutions (in comments).
The last one worked and I have made a slight modification of it.
Thanks all for the effort and especially #WiktorStribiżew!
EDIT
Ok, yes #Bohemian it does not match 2-digits, I forgot to update:
(?<=(ns\d{0,2}:OutputData)>)(.*?)(?=<\/\1)
I have such txt file:
ххх.prontube.ru
salo.ru
bbb.antichat.ru
yyy.ru
xx.bb.prontube.ru
zzz.com
srfsf.jwbefw.com.ua
Trying to delete all subdomains with such regex:
Find: .+\.((.*?)\.(ru|ua|com\.ua|com|net|info))$
Replace with: \1
Receive:
prontube.ru
salo.ru
antichat.ru
yyy.ru
prontube.ru
zzz.com
com.ua
Why last line becomes com.ua instead of jwbefw.com.ua ?
This works without look around:
Find: [a-zA-Z0-9-.]+\.([a-zA-Z0-9-]+)\.([a-zA-Z0-9-]+)$
Replace: \1\.\2
It finds something with at least 2 periods and only letters, numbers, and dashes following the last two periods; then it replaces it with the last 2 parts. More intuitive, in my opinion.
There's something funny going on with that leading xxx. It doesn't appear to be plain ASCII. For the sake of this question, I'm going to assume that's just something funny with this site and not representative of your real data.
Incorrect
Interestingly, I previously had an incorrect answer here that accumulated a lot of upvotes. So I think I should preserve it:
Find: [a-zA-Z0-9-]+\.([a-zA-Z0-9-]+)\.(.+)$
Replace: \1\.\2
It just finds a host name with at least 2 periods in it, then replaces it with everything after the first dot.
The .+ part is matching as much as possible. Try using .+? instead, and it will capture the least possible, allowing the com.ua option to match.
.+?\.([\w-]*?\.(?:ru|ua|com\.ua|com|net|info))$
This answer still uses the specific domain names that the original question was looking at. As some TLD (top level domains) have a period in them, and you could theoretically have a list including multiple subdomains, whitelisting the TLD in the regex is a good idea if it works with your data set. Both current answers (from 2013) will not handle the difference between "xx.bb.prontube.ru" and "srfsf.jwbefw.com.ua" correctly.
Here is a quick explanation of why this psnig's original regex isn't working as intended:
The + is greedy.
.+ will zip all the way to the right at the end of the line capturing everything,
then work its way backwards (to the left) looking for a match from here:
(ru|ua|com\.ua|com|net|info)
With srfsf.jwbefw.com.ua the regex engine will first fail to match a,
then it will move the token one place to the left to look at "ua"
At that point, ua from the regex (the second option) is a match.
The engine will not keep looking to find "com.ua" because ".ua" met that requirement.
Niet the Dark Absol's answer tells the regex to be "lazy"
.+? will match any character (at least one) and then try to find the next part of the regex. If that fails, it will advance the token, .+ matching one more character and then evaluating the rest of the regex again.
The .+? will eventually consume: srfsf.jwbefw before matching the period, and then matching com.ua.
But the implimentation of ? also creates issues.
Adding in the question mark makes that first .+ lazy, but then causes group1 to match bb.prontube.ru instead of prontube.ru
This is because that first period after the bb will match, then inside group 1 (.*?) will match bb.prontube. before \.(ru|ua|com\.ua|com|net|info))$ matches .ru
To avoid this, change that third group from (.*?) to ([\w-]*?) so it won't capture . only letters and numbers, or a dash.
resulting regex:
.+?\.(([\w-])*?\.(ru|ua|com\.ua|com|net|info))$
Note that you don't need to capture any groups other than the first. Adding ?: makes the TLD options non-capturing.
last change:
.+?\.([\w-]*?\.(?:ru|ua|com\.ua|com|net|info))$
Search what: .+?\.(\w+\.(?:ru|com|com\.au))
Replace with: $1
Look in the picture above, what regex capture referring
It's color the way you will not need a regex explaination anymore ....