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Jozef
Jozef

Reputation: 493

Shell script - proper quoting in the awk command

I have a awk command with 2 parameters and one condition - if it is fullfilled, it returns second parameter. So far, it looks like this and works well

awk -v PARAM_NAME="user" '{ if ($1 == "\""PARAM_NAME"\":") { print $2;}}'

Now, I would like to add one check and see if the second parameter ends with a certain character. I know that, in order to read the last character of $2, I need to read it like this.

echo "${2: -1}"

The problem is - I dont know how to escape those double quetes properly (or at least thats where I think the problem lies). This is what I have now, could someone tell me what is wrong with it? Thank you

awk -v PARAM_NAME="user" '{ if ($1 == "\""PARAM_NAME"\":" && "${2: -1}" == "\"","\"") { print $2;}}'

Whole command

cf env some-odata-app | grep "\"hana\":" -A 30 | awk -v PARAM_NAME="user" -v lastchar="${2: -1}" '{ if ($1 == "\""PARAM_NAME"\":" && lastchar == ",") { print substr($2, 2, length($2)-3);}}'

Expected input after first two commands. I want to get both password and user, cleared from quotes. So need to know if to cut two or three characters from the end

"hana": [
   {
    "binding_name": null,
    "credentials": {  
     "password": "obfuscated",
     "schema": "oiuhjoiuhyupoihj",
     "url": "pkpokpokp[kjpo[kpo",
     "user": "USER"
    },
 
  ]

Upvotes: 1

Views: 64

Answers (2)

markp-fuso
markp-fuso

Reputation: 34134

The gist of the question appears to have changed from 'passing shell parameters into awk' to 'pulling last character from a awk variable/field' to 'parsing out the user and password from a cf/grep command batch'.

Sample data generated by the cf/grep command batch:

$ cat hana.dat
"hana": [
   {
    "binding_name": null,
    "credentials": {  
     "password": "obfuscated",
     "schema": "oiuhjoiuhyupoihj",
     "url": "pkpokpokp[kjpo[kpo",
     "user": "USER"
    },
   ]

OP wants to run 2 separate commands, one to extract the user and one to extract the password.

One awk solution that uses the double quote as the input field separator:

$ awk -F'"' -v PARAM_NAME="user" '$2 == PARAM_NAME { print $4 }' hana.dat
USER
$ awk -F'"' -v PARAM_NAME="password" '$2 == PARAM_NAME { print $4 }' hana.dat
obfuscated

Keep in mind we can also pull both values via a single awk call, eg:

$ awk -F'"' '$2 == "password" || $2 == "user" {print $4}' hana.dat
obfuscated
USER

One grep/cut idea that emulates the awk solution:

$ grep -E 'password|user' hana.dat | cut -d'"' -f4
obfuscated
USER

NOTE: Will likely need to reformat the output depending on how OP plans to capture and use these values.

Upvotes: 1

markp-fuso
markp-fuso

Reputation: 34134

OP can add a second -v flag to pull in the last character of a shell variable, eg:

awk -v PARAM_NAME="xxx_param" -v lastchar="${2: -1}" '{ if ($1 == "\""PARAM_NAME"\":" && lastchar == "\""e"\"") { print $2;}}'

If the objective is to find the last character of an input field we can use a combination of the length() and substr() functions, eg,

$ awk '{ print substr($1,length($1),1) }' <<< 'STUVWXYZ'
Z

Upvotes: 1

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