Commands tagged validation (5)

  • JSON processing with Python

    Validates and pretty-prints the content fetched from the URL. Show Sample Output


    13
    curl -s "http://feeds.delicious.com/v2/json?count=5" | python -m json.tool | less -R
    keimlink · 2010-03-24 09:15:12 16
  • validate the syntax of a perl-compatible regular expression

    Place the regular expression you want to validate between the forward slashes in the eval block. Show Sample Output


    5
    perl -we 'my $regex = eval {qr/.*/}; die "$@" if $@;'
    tlacuache · 2009-10-13 21:50:47 4
  • Check if variable is a number

    Using the standard numeric comparison but suppressing the STDERR output acts as the simplest way to check a value is numeric. See sample output for some examples. Show Sample Output


    0
    if [ "$testnum" -eq "$testnum" 2>/dev/null ]; then echo It is numeric; fi
    jgc · 2009-10-09 14:57:27 7
  • quick and easy way of validating a date format of yyyy-mm-dd and returning a boolean

    On CentOS at least, date returns a boolean for the common date string formats, including YYYY-MM-DD. In the sample output, you can see various invalid dates returning 0 whereas a simple regex check would return 1 for the invalid dates. -d, --date=STRING display time described by STRING, not `now' The version of date on OS X does not appear to have this same option. Show Sample Output


    0
    if date -d 2006-10-10 >> /dev/null 2>&1; then echo 1; else echo 0; fi
    SteveGoossens · 2013-01-10 10:35:15 5
  • quick and easy way of validating a date format of yyyy-mm-dd and returning a boolean

    Quick and easy way of validating a date format of yyyy-mm-dd and returning a boolean, the regex can easily be upgraded to handle "in betweens" for mm dd or to validate other types of strings, ex. ip address. Boolean output could easily be piped into a condition for a more complete one-liner.


    -1
    echo 2006-10-10 | grep -c '^[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9]$'
    rez0r · 2009-05-11 22:18:43 5

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Encodes HTML entities from input (file or stdin) so it's possible to directly past the result to a blog or HTML source file.

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Find broken symlinks and delete them
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Check reverse DNS
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Replace 'csv_file.csv' with your filename.

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Search commandlinefu from the command line
There's probably a more efficient way to do this rather than the relatively long perl program, but perl is my hammer, so text processing looks like a nail. This is of course a lot to type all at once. You can make it better by putting this somewhere: $ clf () { (curl -d "q=$@" http://www.commandlinefu.com/search/autocomplete 2>/dev/null) | egrep 'autocomplete|votes|destination' | perl -pi -e 's/$/\n\n/g;s/^ +|\([0-9]+ votes,//g;s/^\//http:\/\/commandlinefu.com\//g'; } Then, to look up any command, you can do this: $ clf diff This is similar to http://www.colivre.coop.br/Aurium/CLFUSearch except that it's just one line, so more in the spirit of CLF, in my opinion.

Replace Every occurrence of a word in a file
Replace 'this' with 'that'

Want to known what time is it in another part of the world ?
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Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

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