I am trying to build a connection string that requires pulling 3 IP addresses from another config file. When I get those values, I need to replace the port on each. I plan to replace each port using simple Bash find and replace ${string/pattern/replacement} but my problem is I'm stuck on the best way to parse the pattern out of the IP.
Here is what I have so far:
myFile.config:
ip.1=ip-ip-1-address:1234:5678
ip.2=ip-ip-2-address:1234:5678
ip.3=ip-ip-3-address:1234:5678
Copying some other simple process, I found I can pull the value of each IP like this:
IP1=`grep "ip.1=" /path/to/conf/myFile.config | awk -F "=" '{print $2}'`
which gives me ip.1=ip-ip-1-address:1234:5678. However, I need to replace 1234:5678 with 6543 for example. I've been looking around and I found this awesome answer that detailed using Bash prefix substitution but that relies on knowing the parameter. for example, I would have to do it this way:
test=${ip1##ip-ip-1-address:}
which results in $test being 1234:5678. That's fine but maybe I don't know the IP address as the parameter, so I'm back to considering regex unless there's a way for me to use * as the parameter or something, but I have been unsuccessful so far. For regex, I have tried a bunch such as test=${ip1/(?<=:).*/}.
Note that ${ip1/(?<=:).*/} you tried is an example of string manipulation syntax that does not support regex, only specific patterns.
You seem to want
x='ip.1=ip-ip-1-address:1234:5678'
echo "${x%%:*}:6543" # => ip.1=ip-ip-1-address:6543
The ${x%%:*} takes the value of x and removes all chars from the end till the first : including it. :6543 is added to the result of this manipulation using "${x%%:*}:6543".
To extract that value, you may also use
awk '/^ip\.1=/{sub("^[^:]+:", "");print}' myFile.config
The awk command finds lines starting with ip.1= and then removes all text from the start till the first colon including the colon and only prints these values.
Friends:
I have to process a CSV file, using Perl language and produce an Excel as output, using the Excel::Writer::XSLX module. This is not a homework but a real life problem, where I cannot download whichever Perl version (actually, I need to use Perl 5.6), or whichever Perl module (I have a limited set of them). My OS is UNIX. I can also use (embedding in Perl) ksh and csh (with some limitation, as I have found so far). Please, limit your answers to the tools I have available. Thanks in advance!
Even though I am not a Perl developer, but coming from other languages, I have already done my work. However, the customer is asking for extra processing where I am getting stuck on.
1) The stones in the road I found are coming from two sides: from Perl and from Excel particular styles of processing data. I already found a workaround to handle the Excel, but -as mentioned in the subject- I have difficulties while processing zeroes found in CSV input file. To handle the Excel, I am using the '0 way which is the final way for data representation that Excel seems to have while using the # formatting style.
2) Scenario:
I need to catch standalone zeroes which might be present in whichever line / column / cell of the CSV input file and put them as such (as zeroes) in the Excel output file.
I will go directly to the point of my question to avoid loosing your valuable time. I am providing more details after my question:
Research and question:
I tried to use Perl regex to find standalone "0" and replace them by whichever string, planning to replace them back to "0" at the end of processing.
perl -p -i -e 's/\b0\b/string/g' myfile.csv`
and
perl -i -ple 's/\b0\b/string/g' myfile.csv
Are working; but only from command line. They aren't working when I call them from the Perl script as follows:
system("perl -i -ple 's/\b0\b/string/g' myfile.csv")
Do not know why... I have already tried using exec and eval, instead of system, with the same results.
Note that I have a ton of regex that work perfectly with the same structure, such as the following:
system("perl -i -ple 's/input/output/g' myfile.csv")
I have also tried using backticks and qx//, without success. Note that qx// and backticks have not the same behavior, since qx// is complaining about the boundaries \b because of the forward slash.
I have tried using sed -i, but my System is rejecting -i as invalid flag (do not know if this happens in all UNIX, but at least happens in the one at work. However is accepting perl -i).
I have tried embedding awk (which is working from command line), in this way:
system `awk -F ',' -v OFS=',' '$1 == \"0\" { $1 = "string" }1' myfile.csv > myfile_copy.csv
But this works only for the first column (in command line) and, other than having the disadvantage of having extra copy file, Perl is complaining for > redirection, assuming it as "greater than"...
system(q#awk 'BEGIN{FS=OFS=",";split("1 2 3 4 5",A," ") } { for(i in A)sub(0,"string",$A[i] ) }1' myfile.csv#);
This awk is working from command line, but only 5 columns. But not in Perl using #.
All the combinations of exec and eval have also been tested without success.
I have also tried passing to system each one of the awk components, as arguments, separated by commas, but did not find any valid way to pass the redirector (>), since Perl is rejecting it because of the mentioned reason.
Using another approach, I noticed that the "standalone zeroes" seem to be "swallowed" by the Text::CSV module, thus, I get rid off it, and turned back to a traditional looping in csv line by line and a spliter for commas, preserving the zeroes in that way. However I found the "mystery" of isdual in Perl, and because of the limitation of modules I have, I cannot use the Dumper. Then, I also explored the guts of binaries in Perl and tried the $x ^ $x, which was deprecated since version 5.22 but valid till that version (I said mine is 5.6). This is useful to catch numbers vs strings. However, while if( $x ^ $x ) returns TRUE for strings, if( !( $x ^ $x ) ) does not returns TRUE when $x = 0. [UPDATE: I tried this in a devoted Perl script, just for this purpose, and it is working. I believe that my probable wrong conclusion ("not returning TRUE") was obtained when I did not still realize that Text::CSV was swallowing my zeroes. Doing new tests...].
I will appreciate very much your help!
MORE DETAILS ON MY REQUIREMENTS:
1) This is a dynamic report coming from a database which is handover to me and I pickup programmatically from a folder. Dynamic means that it might have whichever amount of tables, whichever amount of columns in each table, whichever names as column headers, whichever amount of rows in each table.
2) I do not know, and cannot know, the column names, because they vary from report to report. So, I cannot be guided by column names.
A sample input:
Alfa,Alfa1,Beta,Gamma,Delta,Delta1,Epsilon,Dseta,Heta,Zeta,Iota,Kappa
0,J5,alfa,0,111.33,124.45,0,0,456.85,234.56,798.43,330000.00
M1,0,X888,ZZ,222.44,111.33,12.24,45.67,0,234.56,0,975.33
3) Input Explanation
a) This is an example of a random report with 12 columns and 3 rows. Fist row is header.
b) I call "standalone zeroes" those "clean" zeroes which are coming in the CSV file, from second row onwards, between commas, like 0, (if the case is the first position in the row) or like ,0, in subsequent positions.
c) In the second row of the example you can read, from the beginning of the row: 0,J5,alfa,0, which in this particular case, are "words" or "strings". In this case, 4 names (note that two of them are zeroes, which required to be treated as strings). Thus, we have a 4 names-columns example (Alfa,Alfa1,Beta,Gamma are headers for those columns, but only in this scenario). From that point onwards, in the second row, you can see floating point (*.00) numbers and, among them, you can see 2 zeroes, which are numbers. Finally, in the third line, you can read M1,0,X888,Z, which are the names for the first 4 columns. Note, please, that the 4th column in the second row has 0 as name, while the 4th column in the third row has ZZ as name.
Summary: as a general picture, I have a table-report divided in 2 parts, from left to right: 4 columns for names, and 8 columns for numbers.
Always the first M columns are names and the last N columns are numbers.
- It is unknown which number is M: which amount of columns devoted for words / strings I will receive.
- It is unknown which number is N: which amount of columns devoted for numbers I will receive.
- It is KNOWN that, after the M amount of columns ends, always starts N, and this is constant for all the rows.
I have done a quick research on Perl boundaries for regex ( \b ), and I have not found any relevant information regarding if it applies or not in Perl 5.6.
However, since you are using and old Perl version, try the traditional UNIX / Linux style (I mean, what Perl inherits from Shell), like this:
system("perl -i -ple 's/^0/string/g' myfile.csv");
The previous regex should do the work doing the change at the start of the each line in your CSV file, if matches.
Or, maybe better (if you have those "standalone" zeroes, and want avoid any unwanted change in some "leading zeroes" string):
system("perl -i -ple 's/^0,/string,/g' myfile.csv");
[Note that I have added the comma, after the zero; and, of course, after the string].
Note that the first regex should work; the second one is just a "caveat", to be cautious.
We are using a simple curl to get metrics via an API. The problem is, that the output is fixed in the amount of arguments but not their position within the output.
We need to do this with a "simple" regex since the tool only accepts this.
/"name":"(.*)".*?"memory":(\d+).*?"consumer_utilisation":(\w+|\d+).*?"messages_unacknowledged":(\d+).*?"messages_ready":(\d+).*?"messages":(\d+)/s
It works fine for:
{"name":"queue1","memory":89048,"consumer_utilisation":null,"messages_unacknowledged":0,"messages_ready":0,"messages":0}
However if the output order is changed, then it doesn't match any more:
{"name":"queue2","consumer_utilisation":null,"messages_unacknowledged":0,"messages_ready":0,"messages":0,"memory":21944}
{"name":"queue3","consumer_utilisation":null,"messages_unacknowledged":0,"messages_ready":0,"memory":21944,"messages":0}
I need a relative definition of the strings to match, since I never know at which position they will appear. Its in total 9 different queue-metric-groups.
The simple option is to use a regex for each key-value pair instead of one large regex.
/"name":"((?:[^\\"]|\\.)*)"/
/"memory":(\d+)/
This other option is not a regex, but might be sufficient. Instead of using regex, you could simply transform the resulting response before reading it. Since you say "We are using a simple curl" I'm guessing you're talking about the Curl command line tool. You could pipe the result into a simple Perl command.
perl -ne 'use JSON; use Text::CSV qw(csv); $hash = decode_json $_; csv (sep_char=> ";", out => *STDOUT, in => [[$hash->{name}, $hash->{memory}, $hash->{consumer_utilisation}, $hash->{messages_unacknowledged}, $hash->{messages_ready}, $hash->{messages}]]);'
This will keep the order the same, making it easier to use a regex to read out the data.
input
{"name":"queue1","memory":89048,"consumer_utilisation":null,"messages_unacknowledged":0,"messages_ready":0,"messages":0}
{"name":"queue2","consumer_utilisation":null,"messages_unacknowledged":0,"messages_ready":0,"messages":0,"memory":21944}
{"name":"queue3","consumer_utilisation":null,"messages_unacknowledged":0,"messages_ready":0,"memory":21944,"messages":0}
output
queue1;89048;;0;0;0
queue2;21944;;0;0;0
queue3;21944;;0;0;0
For this to work you need Perl and the packages JSON and Text::CSV installed. On my system they are present in perl, libjson-perl and libtext-csv-perl.
note: I'm currently using ; as separator. If this is included into one of the output will be surrounded by double quotes. "name":"que;ue1" => "que;ue1";89048;;0;0;0 If the value includes both a ; and a " the " will be escaped by placing another one before it. "name":"q\"ue;ue1" => "q""ue;ue1";89048;;0;0;0
I'm trying to use a powershell regex to pull version data from the AssemblyInfo.cs file. The regex below is my best attempt, however it only pulls the string [assembly: AssemblyVersion(". I've put this regex into a couple web regex testers and it LOOKS like it's doing what I want, however this is my first crack at using a powershell regex so I could be looking at it wrong.
$s = '[assembly: AssemblyVersion("1.0.0.0")]'
$prog = [regex]::match($s, '([^"]+)"').Groups[1].Value
You also need to include the starting double quotes otherwise it would start capturing from the start until the first " is reached.
$prog = [regex]::match($s, '"([^"]+)"').Groups[1].Value
^
Try this regex "([^"]+)"
Regex101 Demo
Regular expressions can get hard to read, so best practice is to make them as simple as they can be while still solving all possible cases you might see. You are trying to retrieve the only numerical sequence in the entire string, so we should look for that and bypass using groups.
$s = '[assembly: AssemblyVersion("1.0.0.0")]'
$prog = [regex]::match($s, '[\d\.]+').Value
$prog
1.0.0.0
For the generic solution of data between double quotes, the other answers are great. If I were parsing AssemblyInfo.cs for the version string however, I would be more explicit.
$versionString = [regex]::match($s, 'AssemblyVersion.*([0-9].[0-9].[0-9].[0-9])').Groups[1].Value
$version = [version]$versionString
$versionString
1.0.0.0
$version
Major Minor Build Revision
----- ----- ----- --------
1 0 0 0
Update/Edit:
Related to parsing the version (again, if this is not a generic question about parsing text between double quotes) is that I would not actually have a version in the format of M.m.b.r in my file because I have always found that Major.minor are enough, and by using a format like 1.2.* gives you some extra information without any effort.
See Compile date and time and Can I generate the compile date in my C# code to determine the expiry for a demo version?.
When using a * for the third and fourth part of the assembly version, then these two parts are set automatically at compile time to the following values:
third part is the number of days since 2000-01-01
fourth part is the number of seconds since midnight divided by two (although some MSDN pages say it is a random number)
Something to think about I guess in the larger picture of versions, requiring 1.2.*, allowing 1.2, or 1.2.3, or only accepting 1.2.3.4, etc.
I'm trying to change the case of method names for some functions from lowercase_with_underscores to lowerCamelCase for lines that begin with public function get_method_name(). I'm struggling to get this done in a single step.
So far I have used the following
:%s/\(get\)\([a-zA-Z]*\)_\(\w\)/\1\2\u\3/g
However, this only replaces one _ character at a time. What I would like it a search and replace that does something like the following:
Identify all lines containing the string public function [gs]et.
On these lines, perform the following search and replace :s/_\(\w\)/\u\1/g
(
EDIT:
Suppose I have lines get_method_name() and set_method_name($variable_name) and I only want to change the case of the method name and not the variable name, how might I do that? The get_method_name() is more simple of course, but I'd like a solution that works for both in a single command. I've been able to use :%g/public function [gs]et/ . . . as per the solution listed below to solve for the get_method_name() case, but unfortunately not the set_method_name($variable_name) case.
If I've understood you correctly, I don't know why the things you've tried haven't worked but you can use g to perform a normal mode command on lines matchings a pattern.
Your example would be something like:
:%g/public function [gs]et/:s/_\(\w\)/\u\1/g
Update:
To match only the method names, we can use the fact that there will only be method names before the first $, as this looks to be PHP.
To do that, we can use a negative lookbehind, #<!:
:%g/public function [gs]et/:s/\(\$.\+\)\#<!_\(\w\)/\u\2/g
This will look behind #<! for any $ followed by any number of characters and only match _\(\w\) if no $s are found.
Bonus points(?):
To do this for multiple buffers stick a bufdo in front of the %g
You want to use a substitute with an expression (:h sub-replace-expression)
Match the complete string you want to process then pass that string to a second substitute command to actually change the string
:%s/\(get\|set\)\zs_\w\+/\=substitute(submatch(0), '_\([A-Za-z]\)', '\U\1', 'g')
Running the above on
get_method_name($variable_name)
set_method_name($variable_name)
returns
getMethodName($variable_name)
setMethodName($variable_name)
To have vi do replace sad with happy, on all lines, in a file:
:1, $ s/sad/happy/g
(It is the :1, $ before the sed command that instructs vi to execute the command on every line in the file.)