[SOLVED] (BASH) How to assign 2 variables to same line?

Dick Dastardly · 01-14-2012, 05:31 PM

Hello to all.
I'm trying to write a small bash funtion that retrieves Xbox Live Deal of the Week info.

Here's what i have so far:

Code:

xbox()
{
  # get xbox live deals of the week game titles
  xbox_name=$(curl -s http://marketplace.xbox.com/en-US/Promotion/dealoftheweek|grep -i "a class"|grep -i "title="|cut -d"\"" -f6)

  # get deal prices
  xbox_price=$(curl -s http://marketplace.xbox.com/en-US/Promotion/dealoftheweek|grep -i "mspoints goldprice"|cut -d">" -f3|cut -d"<" -f1)

  # display info
  echo -e "$xbox_name""\n$xbox_price"
}

I'm not very proficient so my method of obtaining the title and price may be a bit crude but grep and cut are tools i'm familiar with. I'd love to hear any other ways to do it.

My issue is getting the title and price on the same line. As of now, the output looks like this:

Code:

Defense Grid
Orcs Must Die!
Dungeon Defenders
South Park
400
600
800
400

I'd like it to look like this:

Code:

Defense Grid        400
Orcs Must Die!      600
Dungeon Defenders   800
South Park          400

Should i be trying to put both the title and price inside it's own variable (if so how would one achieve this?) or is there a way to echo it?

Any help is much obliged.

Roken · 01-14-2012, 06:56 PM

This will do it:

Code:

#!/bin/bash
IFS='
'

xbox_name=($(curl -s http://marketplace.xbox.com/en-US/Promotion/dealoftheweek|grep -i "a class"|grep -i "title="|cut -d"\"" -f6))
xbox_price=($(curl -s http://marketplace.xbox.com/en-US/Promotion/dealoftheweek|grep -i "mspoints goldprice"|cut -d">" -f3|cut -d"<" -f1))
loop=${#xbox_name[*]}
for ((counter=0; counter<=$loop; counter++))
do
  echo "${xbox_name[$counter]}" "${xbox_price[$counter]}"
done

"IFS=" forces bash to delimit at line breaks rather than spaces
The next two lines read name and price into arrays
loop= gets the number of array items
And the rest iterates through the array, echoing the name and corresponding price on each line.

I didn't bother looking at how you are reading the input since it seems to do the job.

Note, if you want to tabulate it like your example you'll have to play with your formatting for the echo - but I'm not doing everything for you

Dick Dastardly · 01-14-2012, 07:22 PM

Thanks for the solution Roken

Been tinkering with the echo to no avail....yet!
This is what i'd assume it to be but it doesn't seem right.

Code:

echo -e "${xbox_name[$counter]}" "\t\t${xbox_price[$counter]} MSP"

Roken · 01-14-2012, 08:30 PM

OK, try this:

Code:

#!/bin/bash
IFS='
'

xbox_name=($(curl -s http://marketplace.xbox.com/en-US/Promotion/dealoftheweek|grep -i "a class"|grep -i "title="|cut -d"\"" -f6))
xbox_price=($(curl -s http://marketplace.xbox.com/en-US/Promotion/dealoftheweek|grep -i "mspoints goldprice"|cut -d">" -f3|cut -d"<" -f1))
loop=${#xbox_name[*]}
for ((counter=0; counter<$loop; counter++))
do
  name="${xbox_name[$counter]}\t"
  if [ "${#xbox_name[$counter]}" -lt 16 ]; then
     name="$name\t"
  fi

  echo -e "$name${xbox_price[$counter]} MSP"
done

The extra test is to allow for longer names. Two tabs added for less than 16 characters, only one for more than 16 characters.

Dick Dastardly · 01-14-2012, 09:43 PM

Thank you a million times!
I couldn't work it out so went for this in the end (though i'll use yours now)

Code:

....
for ((counter=0; counter<="$loop"; counter++)); do
    echo -e "${xbox_name[$counter]}"; echo -e "${xbox_price[$counter]} MSP"; echo
done|head -n -4

grail · 01-14-2012, 11:19 PM

Just in case it doesn't have to be bash:

Code:

#!/usr/bin/awk -f

BEGIN{	FS = "[<>]" 
	OFS = "|" }

/ProductBox/{
	gsub(/.*=/,"",$2)
	title[++i] = $2
}

/ProductPrices/{ price[i] = $5	}

END{
	for( x = 1; x <= i; x++ )
		print title[x],price[x]
}

And you can run it like so for results:

Code:

$ curl -s http://marketplace.xbox.com/en-US/Promotion/dealoftheweek | ./d.awk | column -t -s "|"
"Defense Grid"       400
"Orcs Must Die!"     600
"Dungeon Defenders"  800
"South Park"         400

David the H. · 01-15-2012, 01:35 AM

I'd like to point out that, for efficiency purposes, it's generally better to download the entire data set only once, and parse the saved text as needed.

Code:

xdata=$( curl -s http://marketplace.xbox.com/en-US/Promotion/dealoftheweek | grep -e "ProductBox" -e "GoldPrice" )

mapfile -t titles < <( sed -rn 's/.*title="([^"]*)".*/\1/p' <<<"$xdata" )
mapfile -t prices < <( sed -rn 's/.*GoldPrice ProductPrice">([^<]+)<.*/\1/p' <<<"$xdata" )

for i in "${!titles[@]}"; do

	tabs='\t'
	(( ${#titles[i]} <= 16 )) && tabs='\t\t'

	printf "%s$tabs%s\n" "${titles[i]}" "${prices[i]}"

done

I used bash 4's new mapfile command to set the arrays instead of the IFS technique Roken used above, and I've simplified his loop a bit. Otherwise it's the same basic procedure. You might even want to add more tabs and more tests for them in case you get some really long tiles.

Other expressions used above (mostly bash-specific):
process substitution
here strings
the ${!array[@]} substitution pattern for listing index numbers
arithmetic evaluation
printf

Edit: I just want to say, grail's use of the column command to format the output is an excellent suggestion. You can modify the loop above to use it like this:

Code:

for i in "${!titles[@]}"; do

	printf "%s|%s\n" "${titles[i]}" "${prices[i]}"

done | column -t -s '|'

grail · 01-15-2012, 02:42 AM

Nice work David

... I will have to read up on mapfile as I tried a bash solution but suffered word splitting without setting IFS.

David the H. · 01-15-2012, 03:51 AM

Yeah, ever since I realized that mapfile could also be used internally for parsing lines from commands, I've found myself using it more and more. It can often be quite a bit less hassle than running it through a while+read loop.

Speaking of which, I'd also written up a traditional loop version that replaced the sed commands with bash regexes, but eventually decided it wasn't worth cluttering up my post with it. I guess it won't hurt to post it now, though.

Code:

tregex='title="([^"]*)"'
pregex='GoldPrice ProductPrice">([^<]+)<'

while read line; do
     [[ $line =~ $tregex ]] && titles+=( "${BASH_REMATCH[1]}" )
     [[ $line =~ $pregex ]] && prices+=( "${BASH_REMATCH[1]}" )
done <<<"$xdata"

Thanks in return for reminding me about column.

Roken · 01-15-2012, 07:27 AM

Quote:

Originally Posted by David the H.

I'd like to point out that, for efficiency purposes, it's generally better to download the entire data set only once, and parse the saved text as needed.

I agree. As I mentioned in my original reply, I didn't really look at the data gathering code since it worked, and I assumed that this is an occasional script anyway, so not big deal re the extra download.

Having said that, mapfile and column I wasn't even aware of. Couple of new things for me to become familiar with

Dick Dastardly · 01-15-2012, 09:17 AM

Thanks for all the great info. I love the way there's always more than one way to do it.
I'll have to do a lot of reading to understand most of what you guys are telling me.
I'll have a play around and see what i come up with.