Hi I'm trying to dynamically create a atrribute value with Nifi and it looks something like this
$(absolute.path:substringAfterLast('\'):trim)
I'm not able to escape that backslash, is there any workaround to this?
We can achieve this in different ways.
Method1:
Instead of using substringAfterLast function use replaceAll function to get the value after
\ (last backslash).
Use UpdateAttribute processor
add new property as
val
${absolute.path:replaceAll('(.*)(?:\\\\(.*?))+$', '$2'):trim()}
This regex will extract the value after last backslash and replaces the absolute.path attribute value with the extracted value.
(or)
Method2:
Use substringAfterLast + trim functions
${absolute.path:substringAfterLast("\\"):trim()}
This should do: ${absolute.path:substringAfterLast('\\'):trim()}.
Your problem is, that you used () instead of {}, you didn't add () after the trim function and you didn't escape the backslash.
This way works.
To add to Shu's answer:
You can also use the path attribute of your Flowfile to retrieve it's parent directory. If I had
C:\foo\bar\myfile.txt then ${path} will give you bar\
I don't know what you want to do with the substring after the last \ considering how #{absolute.path} gives you C:\something\like\this\
Related
There is one condition where I have to split my string in the manner that all the alphabetic characters should stay as one unit and everything else should be separated like the example shown below.
Example:
Some_var='12/1/20 Balance Brought Forward 150,585.80'
output_var=['12/1/20','Balance Brought Forward','150,585.80']
Yes, you could use some regex to get over this.
Some_var = '12/1/20 Balance Brought Forward 150,585.80'
match = re.split(r"([0-9\s\\\/\.,-]+|[a-zA-Z\s\\\/\.,-]+)", Some_var)
print(match)
You will get some extra spaces but you can trim that and you are good to go.
split isn't gonna cut it. You might wanna look into Regular Expressions (abbreviated regex) to accomplish this.
Here's a link to the Python docs: re module
As for a pattern, you could try using something like this:
([0-9\s\\\/\.,-]+|[a-zA-Z\s\\\/\.,-]+)
then trim each part of the output.
I have this for example:
<#445288012218368010>
And I want to get from between <# > symbols the value.
I tried so:
string.replace(/^(?:\<\#)(?:.*)(?:\>)$/gim, '');
But then I don't get any result. It will delete/remove the whole string.
I want only this part: 445288012218368010 (it will be dynamic, so yeah it will be not the same numbers).
Anyway it is for the discord chat bot and I know that there is other methods for check the mentioned names but I want to do that in regex because which I am trying to do can't go the common method.
So yeah how can I get the value from between those symbols?
I need this in node.js regex.
You can use String#match which will return regular expression matches for the string (in this case the RegExp would be <#(\d+)> (the parenthesis around the \d+ make \d+ become its own group). This way you can use <string>.match(/<#(\d+)>/) to get the regular expression results and <string>.match(/<#(\d+)>/)[1] to get the first group of the regex (in this case the number).
You regex matches but you use a non capturing group (?:.*) so you get the full match and replace that with an empty string. Note that you could omit the first and the third non capturing group and use <# and > instead.
You could match what is between the brackets using a capturing group ([^>]+) or (\d+) and use replace and refer the first capturing group $1 in the replacement.
console.log("<#445288012218368010>".replace(/^<#([^>]+)>$/gim, '$1'));
I had the following problem with erb in combination with Puppet, Hiera and templates:
Via Hiera I got the following strings as variables:
First the variable example in an array (data[example])
something with _VARIABLE_ in it
and variable example_information with
some kind of \1 and maybe also a \2
Now I wanted to substitute _VARIABLE_ in a Puppet template with the second string which contains a legit backslash () in it. So I did it like this:
result=data['example'].gsub('_VARIABLE_', #example_information)
So I took example out of an array and filled the placeholder with #example_information.
The result was as follows:
something with some kind of and maybe also a in it
There was no backslash as gsub interpreted them as backreferences. So how can I solve my issue to preserve my backslashes without double escape them in the Hiera file? I need the Hiera variable further in the code without double escaped backslashes.
I now made this to solve that specific problem as follows:
Variable again example
something with _VARIABLE_ in it
and variable example_information with
some kind of \1 and maybe also a \2
Code part in the template:
# we need to parse out any backslashes
info_temp=example_information.gsub('\\', '__BACKSLASH__')
# now we substitute the variables with real data (but w/o backslashes)
result_temp=data['example'].gsub(/__ITEM_NAME__/, info_temp)
# now we put together the real string with backslashes again as before
result=result_temp.gsub('__BACKSLASH__', '\\')
Now the result looks as follows:
something with some kind of \1 and maybe also a \2 in it
Note
Maybe there is a better way to do it but on my research I didn't stumble upon a better solution so please add comments if you know a better way to do it.
I'm trying to create a stream definition that uses two payload fields joined together to create a concatenated string.
stream create --name blah --definition "http | gemfire-json-server --keyExpression=payload.getField('deviceId') + payload.getField('timestamp')" --deploy`
The concatenation piece in the keyExpression is incorrect, what should it be to get it to work inline?
The simplest answer to you is based on the fact that String has concat() method. So, you code may look like:
--keyExpression=payload.getField('deviceId').concat(payload.getField('timestamp'))
From other side, here you are a quote from XD Reference Manual:
It is only necessary to quote parameter values if they contain spaces or the | character. Here the transform processor module is being passed a SpEL expression that will be applied to any data it encounters:
transform --expression='new StringBuilder(payload).reverse()'
And find this chapter, please, for more information about quotes.
I'm trying to use a Make substitution reference to alter a string. The problem being that the string happens to contain an equals = symbol.
For example:
INPUT = -switch1 -switch2=potato -switch3
OUTPUT = $(INPUT:-switch2=%=-switch2=turnip)
all:
#echo TEST : $(OUTPUT)
so in the form $(var:a=b), INPUT is var, -switch2=% is a and -switch2=turnip is b.
Obviously that doesn't work because = is a special character in this context, but I've no idea how to make it realize that this is part of string a.
I've tried quoting, backslashes, alternative escape characters and putting -switch2=% in a variable and using that instead. All to no avail.
I know I can use patsubst, but that'd be adding the first non-POSIX extension to the file and i'd prefer to not be that guy.
Any suggestions appreciated!
You'll have to use a full patsubst function. Substitution references are just a shortcut for patsubst:
OUTPUT = $(patsubst -switch2=%,-switch2=turnip,$(INPUT))