Loop with 2 variables in a bash script

Question

I am trying to utilize an API. I need to either do some type of "for loop" that replaces or utilizes 2 variables...

In pseudo..

# Declare New Servers
newserver=(
box001
box002
box003
box004
box005
)


# Declare hostnames
newhostname=(
box001.domain.com
box002.domain.com
box003.domain.com
box004.domain.com
box005.domain.com
)

I need to replace NEWSERVER and NEWHOSTNAME in

http://server/api/duplicateobject.htm?id=2928&name=NEWSERVER&host=NEWHOSTNAME&targetid=3120

so that it looks like this

http://server/api/duplicateobject.htm?id=2928&name=box001&host=box001.zcloud.com&targetid=3120

I just need it to loop through all of hosts listed.

Solution 1

The criteria isnt defined that well, but this is how I would do it:

hosts=(
box001:box001.domain.com
box002:box002.domain.com
box003:box003.domain.com
box004:box004.domain.com
box005:box005.domain.com
)

uri="http://server/api/duplicateobject.htm?id=2928&name=NEWSERVER&host=NEWHOSTNAME&targetid=3120"

for host in "${hosts[@]}"; do
    IFS=":" names=( $host )
    hosturi="${uri/NEWSERVER/${names[0]}}"
    hosturi="${hosturi/NEWHOSTNAME/${names[1]}}"
    echo "$hosturi"
done

Outputs:

http://server/api/duplicateobject.htm?id=2928&name=box001&host=box001.domain.com&targetid=3120
http://server/api/duplicateobject.htm?id=2928&name=box002&host=box002.domain.com&targetid=3120
http://server/api/duplicateobject.htm?id=2928&name=box003&host=box003.domain.com&targetid=3120
http://server/api/duplicateobject.htm?id=2928&name=box004&host=box004.domain.com&targetid=3120
http://server/api/duplicateobject.htm?id=2928&name=box005&host=box005.domain.com&targetid=3120

---

Advantages:

• Keeps it clear which server name corresponds with which fqdn.
• Its pure bash & uses no external anything.

.

If the server name is always going to be the first part of the fqdn, the array can be even simpler and you can have bash figure the server name out from the fqdn.

Solution 2

If both your arrays are the same length, and you just want to be able access the same index in each, here is an example:

for ((i=0; i < ${#newserver[@]}; i++)); do 
  echo ${newserver[i]} ${newhostname[i]};
done;

Solution 3

Your above arrays and:

url="http://server/api/duplicateobject.htm?id=2928&name=NEWSERVER&host=NEWHOSTNAME&targetid=3120"
for ((i=0; i < ${#newserver[@]}; i++));
do
   echo $url | sed 's/NEWSERVER/'${newserver[i]}'/;s/NEWHOSTNAME/'${newhostname[i]}'/'
done

leads to:

http://server/api/duplicateobject.htm?id=2928&name=box001&host=box001.domain.com&targetid=3120
http://server/api/duplicateobject.htm?id=2928&name=box002&host=box002.domain.com&targetid=3120
http://server/api/duplicateobject.htm?id=2928&name=box003&host=box003.domain.com&targetid=3120
http://server/api/duplicateobject.htm?id=2928&name=box004&host=box004.domain.com&targetid=3120
http://server/api/duplicateobject.htm?id=2928&name=box005&host=box005.domain.com&targetid=3120

Solution 4

If you are using bash, you can use associative arrays:

declare -A servers
servers=(
    [box001]=box001.domain.com
    [box002]=box002.domain.com
    [box003]=box003.domain.com
    [box004]=box004.domain.com
    [box005]=box005.domain.com
)

for server in "${!servers[@]}" ; do
    hostname="${servers[$server]}"
    # do something with $server and $hostname
done

The order that you iterate the servers is not defined. For the above example in my version of bash on my host, the order is box001, box003, box002, box005 and box004. YMMV.

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