Example here:
gitrepo=$(jq -r '.gitrepo' 0.json)
releasetag=$(curl --silent ""https://api.github.com/repos/\"$gitrepo\""/releases/latest" | grep '"tag_name":' | sed -E 's/.*"([^"]+)".*/\1/')
echo "$releasetag"
Used \" to escape characters.
0.json:
{
"type": "github-releases",
"gitrepo": "ipfs/go-ipfs"
}
How to put $gitrepo to work inside $releasetag?
Thanks in advance!
Bash variables expand inside quoted " strings.
gitrepo="$(jq -r '.gitrepo' 0.json)"
releasetag="$(
curl --silent "https://api.github.com/repos/$gitrepo/releases/latest" \
| grep '"tag_name":' | sed -E 's/.*"([^"]+)".*/\1/'
)"
echo "$releasetag"
Btw, as you are using jq to extract .gitrepo from 0.json, you could also use it in the exact same way to extract .tag_name from curl's output (instead of using grep and sed) like so:
gitrepo="$(jq -r '.gitrepo' 0.json)"
releasetag="$(
curl --silent "https://api.github.com/repos/$gitrepo/releases/latest" \
| jq -r '.tag_name'
)"
echo "$releasetag"
And to simplify it even further (depending on your use case), just write:
curl --silent "https://api.github.com/repos/$(jq -r '.gitrepo' 0.json)/releases/latest" \
| jq -r '.tag_name'
Related
I'd like to pick two values from the text file and paste it to another file after certain strings:
#!/bin/bash
IAM_ROLE=$(curl --silent http://169.254.169.254/latest/meta-data/iam/security-credentials)
curl --silent http://169.254.169.254/latest/meta-data/iam/security-credentials/$IAM_ROLE | jq -r '.AccessKeyId, .SecretAccessKey' > /tmp/aws_credentials
curl --silent http://169.254.169.254/latest/dynamic/instance-identity/document | jq -r .region > /tmp/aws_region
{ read -r val1
read -r val2
sed -i 's! access_key= .* *$! access_key= $val1 !; s! secret_key= .* *$! secret_key= $val2 !;' /etc/trafficserver/s3_auth_v4.config
} < /tmp/aws_credentials
/etc/trafficserver/s3_auth_v4.config looks like:
access_key=
secret_key=
version=4
v4-region-map=region_map.config
However sed part of the script is doing nothing.
I have written a script to retrieve certain value from file.json. It works if I provide the value to jq select, but the variable doesn't seem to work (or I don't know how to use it).
#!/bin/sh
#this works ***
projectID=$(cat file.json | jq -r '.resource[] | select(.username=="myemail#hotmail.com") | .id')
echo "$projectID"
EMAILID=myemail#hotmail.com
#this does not work *** no value is printed
projectID=$(cat file.json | jq -r '.resource[] | select(.username=="$EMAILID") | .id')
echo "$projectID"
Consider also passing in the shell variable (EMAILID) as a jq variable (here also EMAILID, for the sake of illustration):
projectID=$(jq -r --arg EMAILID "$EMAILID" '
.resource[]
| select(.username==$EMAILID)
| .id' file.json)
Postscript
For the record, another possibility would be to use jq's env function for accessing environment variables. For example, consider this sequence of bash commands:
EMAILID=foo#bar.com # not exported
EMAILID="$EMAILID" jq -n 'env.EMAILID'
The output is a JSON string:
"foo#bar.com"
I resolved this issue by escaping the inner double quotes
projectID=$(cat file.json | jq -r ".resource[] | select(.username==\"$EMAILID\") | .id")
Little unrelated but I will still put it here,
For other practical purposes shell variables can be used as -
value=10
jq '."key" = "'"$value"'"' file.json
Posting it here as it might help others. In string it might be necessary to pass the quotes to jq. To do the following with jq:
.items[] | select(.name=="string")
in bash you could do
EMAILID=$1
projectID=$(cat file.json | jq -r '.resource[] | select(.username=='\"$EMAILID\"') | .id')
essentially escaping the quotes and passing it on to jq
It's a quote issue, you need :
projectID=$(
cat file.json | jq -r ".resource[] | select(.username=='$EMAILID') | .id"
)
If you put single quotes to delimit the main string, the shell takes $EMAILID literally.
"Double quote" every literal that contains spaces/metacharacters and every expansion: "$var", "$(command "$var")", "${array[#]}", "a & b". Use 'single quotes' for code or literal $'s: 'Costs $5 US', ssh host 'echo "$HOSTNAME"'. See
http://mywiki.wooledge.org/Quotes
http://mywiki.wooledge.org/Arguments
http://wiki.bash-hackers.org/syntax/words
Jq now have better way to access environment variables, you can use env.EMAILID:
projectID=$(cat file.json | jq -r ".resource[] | select(.username==env.EMAILID) | .id")
Another way to accomplish this is with the jq "--arg" flag.
Using the original example:
#!/bin/sh
#this works ***
projectID=$(cat file.json | jq -r '.resource[] |
select(.username=="myemail#hotmail.com") | .id')
echo "$projectID"
EMAILID=myemail#hotmail.com
# Use --arg to pass the variable to jq. This should work:
projectID=$(cat file.json | jq --arg EMAILID $EMAILID -r '.resource[]
| select(.username=="$EMAILID") | .id')
echo "$projectID"
See here, which is where I found this solution:
https://github.com/stedolan/jq/issues/626
I know is a bit later to reply, sorry. But that works for me.
export K8S_public_load_balancer_url="$(kubectl get services -n ${TENANT}-production -o wide | grep "ingress-nginx-internal$" | awk '{print $4}')"
And now I am able to fetch and pass the content of the variable to jq
export TF_VAR_public_load_balancer_url="$(aws elbv2 describe-load-balancers --region eu-west-1 | jq -r '.LoadBalancers[] | select (.DNSName == "'$K8S_public_load_balancer_url'") | .LoadBalancerArn')"
In my case I needed to use double quote and quote to access the variable value.
Cheers.
I also faced same issue of variable substitution with jq. I found that --arg is the option which must be used with square bracket [] otherwise it won't work.. I am giving you sample example below:
RUNNER_TOKEN=$(aws secretsmanager get-secret-value --secret-id $SECRET_ID | jq '.SecretString|fromjson' | jq --arg kt $SECRET_KEY -r '.[$kt]' | tr -d '"')
In case where we want to append some string to the variable value and we are using the escaped double quotes, for example appending .crt to a variable CERT_TYPE; the following should work:
$ CERT_TYPE=client.reader
$ cat certs.json | jq -r ".\"${CERT_TYPE}\".crt" #### This will *not* work #####
$ cat certs.json | jq -r ".\"${CERT_TYPE}.crt\""
I have written a script to retrieve certain value from file.json. It works if I provide the value to jq select, but the variable doesn't seem to work (or I don't know how to use it).
#!/bin/sh
#this works ***
projectID=$(cat file.json | jq -r '.resource[] | select(.username=="myemail#hotmail.com") | .id')
echo "$projectID"
EMAILID=myemail#hotmail.com
#this does not work *** no value is printed
projectID=$(cat file.json | jq -r '.resource[] | select(.username=="$EMAILID") | .id')
echo "$projectID"
Consider also passing in the shell variable (EMAILID) as a jq variable (here also EMAILID, for the sake of illustration):
projectID=$(jq -r --arg EMAILID "$EMAILID" '
.resource[]
| select(.username==$EMAILID)
| .id' file.json)
Postscript
For the record, another possibility would be to use jq's env function for accessing environment variables. For example, consider this sequence of bash commands:
EMAILID=foo#bar.com # not exported
EMAILID="$EMAILID" jq -n 'env.EMAILID'
The output is a JSON string:
"foo#bar.com"
I resolved this issue by escaping the inner double quotes
projectID=$(cat file.json | jq -r ".resource[] | select(.username==\"$EMAILID\") | .id")
Little unrelated but I will still put it here,
For other practical purposes shell variables can be used as -
value=10
jq '."key" = "'"$value"'"' file.json
Posting it here as it might help others. In string it might be necessary to pass the quotes to jq. To do the following with jq:
.items[] | select(.name=="string")
in bash you could do
EMAILID=$1
projectID=$(cat file.json | jq -r '.resource[] | select(.username=='\"$EMAILID\"') | .id')
essentially escaping the quotes and passing it on to jq
It's a quote issue, you need :
projectID=$(
cat file.json | jq -r ".resource[] | select(.username=='$EMAILID') | .id"
)
If you put single quotes to delimit the main string, the shell takes $EMAILID literally.
"Double quote" every literal that contains spaces/metacharacters and every expansion: "$var", "$(command "$var")", "${array[#]}", "a & b". Use 'single quotes' for code or literal $'s: 'Costs $5 US', ssh host 'echo "$HOSTNAME"'. See
http://mywiki.wooledge.org/Quotes
http://mywiki.wooledge.org/Arguments
http://wiki.bash-hackers.org/syntax/words
Jq now have better way to access environment variables, you can use env.EMAILID:
projectID=$(cat file.json | jq -r ".resource[] | select(.username==env.EMAILID) | .id")
Another way to accomplish this is with the jq "--arg" flag.
Using the original example:
#!/bin/sh
#this works ***
projectID=$(cat file.json | jq -r '.resource[] |
select(.username=="myemail#hotmail.com") | .id')
echo "$projectID"
EMAILID=myemail#hotmail.com
# Use --arg to pass the variable to jq. This should work:
projectID=$(cat file.json | jq --arg EMAILID $EMAILID -r '.resource[]
| select(.username=="$EMAILID") | .id')
echo "$projectID"
See here, which is where I found this solution:
https://github.com/stedolan/jq/issues/626
I know is a bit later to reply, sorry. But that works for me.
export K8S_public_load_balancer_url="$(kubectl get services -n ${TENANT}-production -o wide | grep "ingress-nginx-internal$" | awk '{print $4}')"
And now I am able to fetch and pass the content of the variable to jq
export TF_VAR_public_load_balancer_url="$(aws elbv2 describe-load-balancers --region eu-west-1 | jq -r '.LoadBalancers[] | select (.DNSName == "'$K8S_public_load_balancer_url'") | .LoadBalancerArn')"
In my case I needed to use double quote and quote to access the variable value.
Cheers.
I also faced same issue of variable substitution with jq. I found that --arg is the option which must be used with square bracket [] otherwise it won't work.. I am giving you sample example below:
RUNNER_TOKEN=$(aws secretsmanager get-secret-value --secret-id $SECRET_ID | jq '.SecretString|fromjson' | jq --arg kt $SECRET_KEY -r '.[$kt]' | tr -d '"')
In case where we want to append some string to the variable value and we are using the escaped double quotes, for example appending .crt to a variable CERT_TYPE; the following should work:
$ CERT_TYPE=client.reader
$ cat certs.json | jq -r ".\"${CERT_TYPE}\".crt" #### This will *not* work #####
$ cat certs.json | jq -r ".\"${CERT_TYPE}.crt\""
I am getting a list of quoted strings back from AWS,
and I would like to isolate one of them into a parameter.
the command I am using is:
allelb=$(aws elb describe-load-balancers --query 'LoadBalancerDescriptions[].LoadBalancerName') && echo $allelb
And this is the output I am getting:
[ "elb-app-mprest-dev", "elb-core-mprest-dev", "api-vector-k8s-local-0j8ccl", "a2e6a899d111011e897b0067693cf815", "api-clusters-sydney7-mpre-rqae1h" ]
What I want to do is, get only the string with the word 'sydney7' inside a parameter. So I will have a new parameter with this content inside :
ELB=api-clusters-sydney7-mpre-rqae1h
This is waht I got so far:
allelb=$(aws elb describe-load-balancers --query 'LoadBalancerDescriptions[].LoadBalancerName' | tr -d '"' | tr -d ',' | tr -d ']' | tr -d '[') && echo $allelb | grep -o sydney7
but the output I get is not good enough-
sydney7
How can I achieve that?
Since the output from your command is a JSON array, you should probably use a program for parsing and filtering JSON, like jq:
$ jq '.[] | match(".*sydney.*").string' <<< "$allelb"
"api-clusters-sydney7-mpre-rqae1h"
If you want it raw, use the -r flag:
$ jq -r '.[] | match(".*sydney.*").string' <<< "$allelb"
api-clusters-sydney7-mpre-rqae1h
With cut
cut -d '"' -f10
with grep
grep -o '[^"]*sydney7[^"]*'
I need to set or access multiple cURL variables so I can access them later in a script. For example:
curl -s --write-out "%{http_code} | %{local_ip} | %{time_total}" "http://endpoint.com/payload"
Now how can I access http_code or local_ip to do things like add them to an bash array, etc? Is the only option to grep them out of the response?
You can pipe your curl command to a read command :
curl -s --write-out "write-out: %{http_code} | %{local_ip} | %{time_total}\n" "http://yahoo.com" | \
sed -n '/^write-out:/ s///p' | \
while IFS='|' read http_code local_ip time_total;
do
printf "http_code: %s\nlocal_ip: %s\ntotal_time: %s\n" $http_code $local_ip $time_total;
# or in an array
curlvars=($http_code $local_ip $time_total)
for data in "${curlvars[#]}"
do
printf "%s | " $data
done
done
I added a \n to the write-out string to allow process it as a line.
The sed command extract the write-out line from the curl output.
In the read command you can define a separator and assign all parsed strings to vars.