Given the following json:
Full file here: https://pastebin.com/Hzt9bq2a
{
"name": "Visma Public",
"domains": [
"accountsettings.connect.identity.stagaws.visma.com",
"admin.stage.vismaonline.com",
"api.home.stag.visma.com",
"api.workbox.dk",
"app.workbox.dk",
"app.workbox.co.uk",
"authz.workbox.dk",
"connect.identity.stagaws.visma.com",
"eaccounting.stage.vismaonline.com",
"eaccountingprinting.stage.vismaonline.com",
"http://myservices-api.stage.vismaonline.com/",
"identity.stage.vismaonline.com",
"myservices.stage.vismaonline.com"
]
}
How can I transform the data to the below. Which is, to identify the domains in the format of site.SLD.TLD present and then remove the duplication of them. (Not including the subdomains, protocols or paths as illustrated below.)
{
"name": "Visma Public",
"domains": [
"workbox.co.uk",
"workbox.dk",
"visma.com",
"vismaonline.com"
]
}
I would like to do so in jq as that is what I've used to wrangled the data into this format so far, but at this stage any solution that I can run on Debian (I'm using bash) without any extraneous tooling ideally would be fine.
I'm aware that regex can be used within jq so I assume the best way is to regex out the domain and then pipe to unique however I'm unable to get anything working so far I'm currently trying this version which seems to me to need only the text transformation stage adding in somehow either during the jq process or with a run over with something like awk after the event perhaps:
jq '[.[] | {name: .name, domain: [.domains[]] | unique}]' testfile.json
This appears to be useful: https://github.com/stedolan/jq/issues/537
One solution was offered which does a regex match to extract the last two strings separated by . and call the unique function on that & works up to a point but doesn't cover site.SLD.TLD that has 2 parts. Like google.co.uk would return only co.uk with this jq for example:
jq '.domains |= (map(capture("(?<x>[[:alpha:]]+).(?<z>[[:alpha:]]+)(.?)$") | join(".")) | unique)'
A programming language is much more expressive than jq.
Try the following snippet with python3.
import json
import pprint
import urllib.request
from urllib.parse import urlparse
import os
def get_tlds():
f = urllib.request.urlopen("https://publicsuffix.org/list/effective_tld_names.dat")
content = f.read()
lines = content.decode('utf-8').split("\n")
# remove comments
tlds = [line for line in lines if not line.startswith("//") and not line == ""]
return tlds
def extract_domain(url, tlds):
# get domain
url = url.replace("http://", "").replace("https://", "")
url = url.split("/")[0]
# get tld/sld
parts = url.split(".")
suffix1 = parts[-1]
sld1 = parts[-2]
if len(parts) > 2:
suffix2 = ".".join(parts[-2:])
sld2 = parts[-3]
else:
suffix2 = suffix1
sld2 = sld1
# try the longger first
if suffix2 in tlds:
tld = suffix2
sld = sld2
else:
tld = suffix1
sld = sld1
return sld + "." + tld
def clean(site, tlds):
site["domains"] = list(set([extract_domain(url, tlds) for url in site["domains"]]))
return site
if __name__ == "__main__":
filename = "Hzt9bq2a.json"
cache_path = "tlds.json"
if os.path.exists(cache_path):
with open(cache_path, "r") as f:
tlds = json.load(f)
else:
tlds = get_tlds()
with open(cache_path, "w") as f:
json.dump(tlds, f)
with open(filename) as f:
d = json.load(f)
d = [clean(site, tlds) for site in d]
pprint.pprint(d)
with open("clean.json", "w") as f:
json.dump(d, f)
May I offer you achieving the same query with jtc: the same could be achieved in other languages (and of course in jq) - the query is mostly how to come up with the regex to satisfy your ask:
bash $ <file.json jtc -w'<domains>l:>((?:[a-z0-9]+\.)?[a-z0-9]+\.[a-z0-9]+)[^.]*$<R:' -u'{{$1}}' /\
-ppw'<domains>l:><q:' -w'[domains]:<[]>j:' -w'<name>l:'
{
"domains": [
"stagaws.visma.com",
"stage.vismaonline.com",
"stag.visma.com",
"api.workbox.dk",
"app.workbox.dk",
"workbox.co.uk",
"authz.workbox.dk"
],
"name": "Visma Public"
}
bash $
Note: it does extract only DOMAIN.TLD, as per your ask. If you like to extract DOMAIN.SLD.TLD, then the task becomes a bit less trivial.
Update:
Modified solution as per the comment: extract domain.sld.tld where 3 or more levels and domain.tld where there’s only 2
PS. I'm the creator of the jtc - JSON processing utility. This disclaimer is SO requirement.
One of the solutions presented on this page offers that:
A programming language is much more expressive than jq.
It may therefore be worthwhile pointing out that jq is an expressive, Turing-complete programming language, and that it would be as straightforward (and as tedious) to capture all the intricacies of the "Public Suffix List" using jq as any other programming language that does not already provide support for this list.
It may be useful to illustrate an approach to the problem that passes the (revised) test presented in the Q. This approach could easily be extended in any one of a number of ways:
def extract:
sub("^[^:]*://";"")
| sub("/.*$";"")
| split(".")
| (if (.[-1]|length) == 2 and (.[-2]|length) <= 3
then -3 else -2 end) as $ix
| .[$ix : ]
| join(".") ;
{name, domain: (.domains | map(extract) | unique)}
Output
{
"name": "Visma Public",
"domain": [
"visma.com",
"vismaonline.com",
"workbox.co.uk",
"workbox.dk"
]
}
Judging from your example, you don't actually want top-level domains (just one component, e.g. ".com"), and you probably don't really want second-level domains (last two components) either, because some domain registries don't operate at the TLD level. Given www.foo.com.br, you presumably want to find out about foo.com.br, not com.br.
To do that, you need to consult the Public Suffix List. The file format isn't too complicated, but it has support for wildcards and exceptions. I dare say that jq isn't the ideal language to use here — pick one that has a URL-parsing module (for extracting hostnames) and an existing Public Suffix List module (for extracting the domain parts from those hostnames).
This is a reported bug in Perl 6: X::AdHoc instead of X::TypeCheck::Binding with subset parameter, first reported in November 2015.
While playing with my Perl 6 module Chemisty::Elements, I've run into an Exception issue I didn't expect.
I define a type, ZInt, which limits numbers to the ordinal numbers found on the periodic chart (which I've faked a bit here). I then use that type to constrain a parameter to a subroutine. I expected to get some sort of X::TypeCheck, but I get X::AdHoc instead:
use v6;
subset ZInt of Cool is export where {
state ( $min, $max ) = <1 120>;
( $_.truncate == $_ and $min <= $_ <= $max )
or warn "Z must be between a positive whole number from $min to $max. Got <$_>."
};
sub foo ( ZInt $Z ) { say $Z }
try {
CATCH {
default { .^name.say }
}
foo( 156 );
}
First, I get the warning twice, which is weird:
Z must be between a positive whole number from 1 to 120. Got <156>. in block at zint.p6 line 5
Z must be between a positive whole number from 1 to 120. Got <156>. in block at zint.p6 line 5
X::AdHoc
But, I get the X::AdHoc type when I'd rather people knew it was a type error.
I checked what would happen without the warn and got X::AdHoc again:
subset ZInt of Cool is export where {
state ( $min, $max ) = <1 120>;
( $_.truncate == $_ and $min <= $_ <= $max )
};
So, I figured I could throw my own exception:
subset ZInt of Cool is export where {
state ( $min, $max ) = <1 120>;
( $_.truncate == $_ and $min <= $_ <= $max )
or X::TypeCheck.new.throw;
};
But, I get a warning:
Use of uninitialized value of type Any in string context
Any of .^name, .perl, .gist, or .say can stringify undefined things, if needed.
At this point I don't know what's complaining. I figure one of those methods expects something I'm not supplying but I don't see anything about parameters for new or throw in the docs.
How do I get the type I want without the warning, along with my custom text?
Don't throw the exception or warn with one. Instead, you want to fail:
subset ZInt of Cool is export where {
state ( $min, $max ) = <1 120>;
( $_.truncate == $_ and $min <= $_ <= $max )
or fail "Z must be between a positive whole number from $min to $max. Got <$_>."
};
I believe that's your intent. Failing with your own exception is fine too, but X::TypeCheck has a bug in it. It should either require "operation" or provide a reasonable default as it does for "got" and "expected".
subset ZInt of Cool is export where {
state ( $min, $max ) = <1 120>;
( $_.truncate == $_ and $min <= $_ <= $max )
or fail X::TypeCheck.new(
operation => "type check",
expected => ::('ZInt'),
got => $_,
);
};
You could pass --ll-exception and try to figure out how exactly you end up with the errors and messages you got, but I'm not sure how helpful that will be.
As to the warning about use of an uninitialzed value: You need to provide a named operation argument to X::TypeCheck.new; other arguments you may provide are got and expected, cf core/Exception.pm.
It is however a Bad Idea to throw from a subset declaration as any smartmatch against that particular type will now explode. A slightly better idea would be to .fail the exception, but that still doesn't feel right to me: Not being a member of a subset type is not an exceptional condition.
Alternatively, you could provide a multi candidate that does the dying:
subset ZInt of Cool where $_ %% 1 && $_ ~~ 1..120;
proto foo($) {*}
multi foo(ZInt $Z) { say $Z }
multi foo($Z) {
die X::TypeCheck.new(
operation => 'foo',
got => $Z,
expected => ZInt
);
}
That still has issues if you provide an argument like "hello" that fails on numeric conversion as %% will throw instead of propagating the failure, which could be considered a defect with the Rakudo core setting.
You can work around that one via things like
subset ZInt of Cool where { try $_ %% 1 && $_ ~~ 1..120 }
or
subset ZInt of Cool where { .Numeric andthen $_ %% 1 && $_ ~~ 1..120 }
The whole interaction of argument type checking, subsets or where-clauses, failures and exceptions can be somewhat brittle, so you may want to experiment a bit until you arrive at semantics and behaviour you like.
Another approach would be doing a coercion from Cool to Int with a separate range check:
subset ZInt of Int where 1..120 ;
sub foo(Int(Cool) $Z where ZInt) {
say $Z.perl;
}
In an ideal world, there should be some way to express this with a coercing type constraint like ZInt(Cool).
I need a regular expression to select all the text between two outer brackets.
Example:
START_TEXT(text here(possible text)text(possible text(more text)))END_TXT
^ ^
Result:
(text here(possible text)text(possible text(more text)))
I want to add this answer for quickreference. Feel free to update.
.NET Regex using balancing groups:
\((?>\((?<c>)|[^()]+|\)(?<-c>))*(?(c)(?!))\)
Where c is used as the depth counter.
Demo at Regexstorm.com
Stack Overflow: Using RegEx to balance match parenthesis
Wes' Puzzling Blog: Matching Balanced Constructs with .NET Regular Expressions
Greg Reinacker's Weblog: Nested Constructs in Regular Expressions
PCRE using a recursive pattern:
\((?:[^)(]+|(?R))*+\)
Demo at regex101; Or without alternation:
\((?:[^)(]*(?R)?)*+\)
Demo at regex101; Or unrolled for performance:
\([^)(]*+(?:(?R)[^)(]*)*+\)
Demo at regex101; The pattern is pasted at (?R) which represents (?0).
Perl, PHP, Notepad++, R: perl=TRUE, Python: PyPI regex module with (?V1) for Perl behaviour.
(the new version of PyPI regex package already defaults to this → DEFAULT_VERSION = VERSION1)
Ruby using subexpression calls:
With Ruby 2.0 \g<0> can be used to call full pattern.
\((?>[^)(]+|\g<0>)*\)
Demo at Rubular; Ruby 1.9 only supports capturing group recursion:
(\((?>[^)(]+|\g<1>)*\))
Demo at Rubular (atomic grouping since Ruby 1.9.3)
JavaScript API :: XRegExp.matchRecursive
XRegExp.matchRecursive(str, '\\(', '\\)', 'g');
Java: An interesting idea using forward references by #jaytea.
Without recursion up to 3 levels of nesting:
(JS, Java and other regex flavors)
To prevent runaway if unbalanced, with * on innermost [)(] only.
\((?:[^)(]|\((?:[^)(]|\((?:[^)(]|\([^)(]*\))*\))*\))*\)
Demo at regex101; Or unrolled for better performance (preferred).
\([^)(]*(?:\([^)(]*(?:\([^)(]*(?:\([^)(]*\)[^)(]*)*\)[^)(]*)*\)[^)(]*)*\)
Demo at regex101; Deeper nesting needs to be added as required.
Reference - What does this regex mean?
RexEgg.com - Recursive Regular Expressions
Regular-Expressions.info - Regular Expression Recursion
Mastering Regular Expressions - Jeffrey E.F. Friedl 1 2 3 4
Regular expressions are the wrong tool for the job because you are dealing with nested structures, i.e. recursion.
But there is a simple algorithm to do this, which I described in more detail in this answer to a previous question. The gist is to write code which scans through the string keeping a counter of the open parentheses which have not yet been matched by a closing parenthesis. When that counter returns to zero, then you know you've reached the final closing parenthesis.
You can use regex recursion:
\(([^()]|(?R))*\)
[^\(]*(\(.*\))[^\)]*
[^\(]* matches everything that isn't an opening bracket at the beginning of the string, (\(.*\)) captures the required substring enclosed in brackets, and [^\)]* matches everything that isn't a closing bracket at the end of the string. Note that this expression does not attempt to match brackets; a simple parser (see dehmann's answer) would be more suitable for that.
This answer explains the theoretical limitation of why regular expressions are not the right tool for this task.
Regular expressions can not do this.
Regular expressions are based on a computing model known as Finite State Automata (FSA). As the name indicates, a FSA can remember only the current state, it has no information about the previous states.
In the above diagram, S1 and S2 are two states where S1 is the starting and final step. So if we try with the string 0110 , the transition goes as follows:
0 1 1 0
-> S1 -> S2 -> S2 -> S2 ->S1
In the above steps, when we are at second S2 i.e. after parsing 01 of 0110, the FSA has no information about the previous 0 in 01 as it can only remember the current state and the next input symbol.
In the above problem, we need to know the no of opening parenthesis; this means it has to be stored at some place. But since FSAs can not do that, a regular expression can not be written.
However, an algorithm can be written to do this task. Algorithms are generally falls under Pushdown Automata (PDA). PDA is one level above of FSA. PDA has an additional stack to store some additional information. PDAs can be used to solve the above problem, because we can 'push' the opening parenthesis in the stack and 'pop' them once we encounter a closing parenthesis. If at the end, stack is empty, then opening parenthesis and closing parenthesis matches. Otherwise not.
(?<=\().*(?=\))
If you want to select text between two matching parentheses, you are out of luck with regular expressions. This is impossible(*).
This regex just returns the text between the first opening and the last closing parentheses in your string.
(*) Unless your regex engine has features like balancing groups or recursion. The number of engines that support such features is slowly growing, but they are still not a commonly available.
It is actually possible to do it using .NET regular expressions, but it is not trivial, so read carefully.
You can read a nice article here. You also may need to read up on .NET regular expressions. You can start reading here.
Angle brackets <> were used because they do not require escaping.
The regular expression looks like this:
<
[^<>]*
(
(
(?<Open><)
[^<>]*
)+
(
(?<Close-Open>>)
[^<>]*
)+
)*
(?(Open)(?!))
>
I was also stuck in this situation when dealing with nested patterns and regular-expressions is the right tool to solve such problems.
/(\((?>[^()]+|(?1))*\))/
This is the definitive regex:
\(
(?<arguments>
(
([^\(\)']*) |
(\([^\(\)']*\)) |
'(.*?)'
)*
)
\)
Example:
input: ( arg1, arg2, arg3, (arg4), '(pip' )
output: arg1, arg2, arg3, (arg4), '(pip'
note that the '(pip' is correctly managed as string.
(tried in regulator: http://sourceforge.net/projects/regulator/)
I have written a little JavaScript library called balanced to help with this task. You can accomplish this by doing
balanced.matches({
source: source,
open: '(',
close: ')'
});
You can even do replacements:
balanced.replacements({
source: source,
open: '(',
close: ')',
replace: function (source, head, tail) {
return head + source + tail;
}
});
Here's a more complex and interactive example JSFiddle.
Adding to bobble bubble's answer, there are other regex flavors where recursive constructs are supported.
Lua
Use %b() (%b{} / %b[] for curly braces / square brackets):
for s in string.gmatch("Extract (a(b)c) and ((d)f(g))", "%b()") do print(s) end (see demo)
Raku (former Perl6):
Non-overlapping multiple balanced parentheses matches:
my regex paren_any { '(' ~ ')' [ <-[()]>+ || <&paren_any> ]* }
say "Extract (a(b)c) and ((d)f(g))" ~~ m:g/<&paren_any>/;
# => (｢(a(b)c)｣ ｢((d)f(g))｣)
Overlapping multiple balanced parentheses matches:
say "Extract (a(b)c) and ((d)f(g))" ~~ m:ov:g/<&paren_any>/;
# => (｢(a(b)c)｣ ｢(b)｣ ｢((d)f(g))｣ ｢(d)｣ ｢(g)｣)
See demo.
Python re non-regex solution
See poke's answer for How to get an expression between balanced parentheses.
Java customizable non-regex solution
Here is a customizable solution allowing single character literal delimiters in Java:
public static List<String> getBalancedSubstrings(String s, Character markStart,
Character markEnd, Boolean includeMarkers)
{
List<String> subTreeList = new ArrayList<String>();
int level = 0;
int lastOpenDelimiter = -1;
for (int i = 0; i < s.length(); i++) {
char c = s.charAt(i);
if (c == markStart) {
level++;
if (level == 1) {
lastOpenDelimiter = (includeMarkers ? i : i + 1);
}
}
else if (c == markEnd) {
if (level == 1) {
subTreeList.add(s.substring(lastOpenDelimiter, (includeMarkers ? i + 1 : i)));
}
if (level > 0) level--;
}
}
return subTreeList;
}
}
Sample usage:
String s = "some text(text here(possible text)text(possible text(more text)))end text";
List<String> balanced = getBalancedSubstrings(s, '(', ')', true);
System.out.println("Balanced substrings:\n" + balanced);
// => [(text here(possible text)text(possible text(more text)))]
The regular expression using Ruby (version 1.9.3 or above):
/(?<match>\((?:\g<match>|[^()]++)*\))/
Demo on rubular
The answer depends on whether you need to match matching sets of brackets, or merely the first open to the last close in the input text.
If you need to match matching nested brackets, then you need something more than regular expressions. - see #dehmann
If it's just first open to last close see #Zach
Decide what you want to happen with:
abc ( 123 ( foobar ) def ) xyz ) ghij
You need to decide what your code needs to match in this case.
"""
Here is a simple python program showing how to use regular
expressions to write a paren-matching recursive parser.
This parser recognises items enclosed by parens, brackets,
braces and <> symbols, but is adaptable to any set of
open/close patterns. This is where the re package greatly
assists in parsing.
"""
import re
# The pattern below recognises a sequence consisting of:
# 1. Any characters not in the set of open/close strings.
# 2. One of the open/close strings.
# 3. The remainder of the string.
#
# There is no reason the opening pattern can't be the
# same as the closing pattern, so quoted strings can
# be included. However quotes are not ignored inside
# quotes. More logic is needed for that....
pat = re.compile("""
( .*? )
( \( | \) | \[ | \] | \{ | \} | \< | \> |
\' | \" | BEGIN | END | $ )
( .* )
""", re.X)
# The keys to the dictionary below are the opening strings,
# and the values are the corresponding closing strings.
# For example "(" is an opening string and ")" is its
# closing string.
matching = { "(" : ")",
"[" : "]",
"{" : "}",
"<" : ">",
'"' : '"',
"'" : "'",
"BEGIN" : "END" }
# The procedure below matches string s and returns a
# recursive list matching the nesting of the open/close
# patterns in s.
def matchnested(s, term=""):
lst = []
while True:
m = pat.match(s)
if m.group(1) != "":
lst.append(m.group(1))
if m.group(2) == term:
return lst, m.group(3)
if m.group(2) in matching:
item, s = matchnested(m.group(3), matching[m.group(2)])
lst.append(m.group(2))
lst.append(item)
lst.append(matching[m.group(2)])
else:
raise ValueError("After <<%s %s>> expected %s not %s" %
(lst, s, term, m.group(2)))
# Unit test.
if __name__ == "__main__":
for s in ("simple string",
""" "double quote" """,
""" 'single quote' """,
"one'two'three'four'five'six'seven",
"one(two(three(four)five)six)seven",
"one(two(three)four)five(six(seven)eight)nine",
"one(two)three[four]five{six}seven<eight>nine",
"one(two[three{four<five>six}seven]eight)nine",
"oneBEGINtwo(threeBEGINfourENDfive)sixENDseven",
"ERROR testing ((( mismatched ))] parens"):
print "\ninput", s
try:
lst, s = matchnested(s)
print "output", lst
except ValueError as e:
print str(e)
print "done"
You need the first and last parentheses. Use something like this:
str.indexOf('('); - it will give you first occurrence
str.lastIndexOf(')'); - last one
So you need a string between,
String searchedString = str.substring(str1.indexOf('('),str1.lastIndexOf(')');
because js regex doesn't support recursive match, i can't make balanced parentheses matching work.
so this is a simple javascript for loop version that make "method(arg)" string into array
push(number) map(test(a(a()))) bass(wow, abc)
$$(groups) filter({ type: 'ORGANIZATION', isDisabled: { $ne: true } }) pickBy(_id, type) map(test()) as(groups)
const parser = str => {
let ops = []
let method, arg
let isMethod = true
let open = []
for (const char of str) {
// skip whitespace
if (char === ' ') continue
// append method or arg string
if (char !== '(' && char !== ')') {
if (isMethod) {
(method ? (method += char) : (method = char))
} else {
(arg ? (arg += char) : (arg = char))
}
}
if (char === '(') {
// nested parenthesis should be a part of arg
if (!isMethod) arg += char
isMethod = false
open.push(char)
} else if (char === ')') {
open.pop()
// check end of arg
if (open.length < 1) {
isMethod = true
ops.push({ method, arg })
method = arg = undefined
} else {
arg += char
}
}
}
return ops
}
// const test = parser(`$$(groups) filter({ type: 'ORGANIZATION', isDisabled: { $ne: true } }) pickBy(_id, type) map(test()) as(groups)`)
const test = parser(`push(number) map(test(a(a()))) bass(wow, abc)`)
console.log(test)
the result is like
[ { method: 'push', arg: 'number' },
{ method: 'map', arg: 'test(a(a()))' },
{ method: 'bass', arg: 'wow,abc' } ]
[ { method: '$$', arg: 'groups' },
{ method: 'filter',
arg: '{type:\'ORGANIZATION\',isDisabled:{$ne:true}}' },
{ method: 'pickBy', arg: '_id,type' },
{ method: 'map', arg: 'test()' },
{ method: 'as', arg: 'groups' } ]
While so many answers mention this in some form by saying that regex does not support recursive matching and so on, the primary reason for this lies in the roots of the Theory of Computation.
Language of the form {a^nb^n | n>=0} is not regular. Regex can only match things that form part of the regular set of languages.
Read more # here
I didn't use regex since it is difficult to deal with nested code. So this snippet should be able to allow you to grab sections of code with balanced brackets:
def extract_code(data):
""" returns an array of code snippets from a string (data)"""
start_pos = None
end_pos = None
count_open = 0
count_close = 0
code_snippets = []
for i,v in enumerate(data):
if v =='{':
count_open+=1
if not start_pos:
start_pos= i
if v=='}':
count_close +=1
if count_open == count_close and not end_pos:
end_pos = i+1
if start_pos and end_pos:
code_snippets.append((start_pos,end_pos))
start_pos = None
end_pos = None
return code_snippets
I used this to extract code snippets from a text file.
This do not fully address the OP question but I though it may be useful to some coming here to search for nested structure regexp:
Parse parmeters from function string (with nested structures) in javascript
Match structures like:
matches brackets, square brackets, parentheses, single and double quotes
Here you can see generated regexp in action
/**
* get param content of function string.
* only params string should be provided without parentheses
* WORK even if some/all params are not set
* #return [param1, param2, param3]
*/
exports.getParamsSAFE = (str, nbParams = 3) => {
const nextParamReg = /^\s*((?:(?:['"([{](?:[^'"()[\]{}]*?|['"([{](?:[^'"()[\]{}]*?|['"([{][^'"()[\]{}]*?['")}\]])*?['")}\]])*?['")}\]])|[^,])*?)\s*(?:,|$)/;
const params = [];
while (str.length) { // this is to avoid a BIG performance issue in javascript regexp engine
str = str.replace(nextParamReg, (full, p1) => {
params.push(p1);
return '';
});
}
return params;
};
This might help to match balanced parenthesis.
\s*\w+[(][^+]*[)]\s*
This one also worked
re.findall(r'\(.+\)', s)