Wait for an HTTP endpoint to return 200 OK with Bash and curl

timeout 300 bash -c 'while [[ "$(curl -s -o /dev/null -w ''%{http_code}'' localhost:9000)" != "200" ]]; do sleep 5; done' || false

version with 5 minutes of timeout: if timeout is reached, it exits with error (1)

For TLS add --insecure flag for self signed certificates
timeout 300 bash -c 'while [[ "$(curl --insecure -s -o /dev/null -w ''%{http_code}'' https://localhost:9000)" != "200" ]]; do sleep 5; done'

How to print status code before sleep?

This is awesome--thanks!

Here a script with timeout

#!/bin/bash
set -eux

declare -r HOST="http://google.com"

wait-for-url() {
    echo "Testing $1"
    timeout -s TERM 45 bash -c \
    'while [[ "$(curl -s -o /dev/null -L -w ''%{http_code}'' ${0})" != "200" ]];\
    do echo "Waiting for ${0}" && sleep 2;\
    done' ${1}
    echo "OK!"
    curl -I $1
}
wait-for-url http://${HOST}

Edit: this one actually works

#!/bin/bash
set -eux

declare HOST=$1
declare STATUS=$2
declare TIMEOUT=$3

HOST=$HOST STATUS=$STATUS timeout --foreground -s TERM $TIMEOUT bash -c \
    'while [[ ${STATUS_RECEIVED} != ${STATUS} ]];\
        do STATUS_RECEIVED=$(curl -s -o /dev/null -L -w ''%{http_code}'' ${HOST}) && \
        echo "received status: $STATUS_RECEIVED" && \
        sleep 1;\
    done;
    echo success with status: $STATUS_RECEIVED'

Here a script with timeout

#!/bin/bash
set -eux

declare -r HOST="http://google.com"

wait-for-url() {
    echo "Testing $1"
    timeout -s TERM 45 bash -c \
    'while [[ "$(curl -s -o /dev/null -L -w ''%{http_code}'' ${0})" != "200" ]];\
    do echo "Waiting for ${0}" && sleep 2;\
    done' ${1}
    echo "OK!"
    curl -I $1
}
wait-for-url http://${HOST}

Testing http://localhost:8000
-bash: timeout: command not found
OK!
i don't think that the timeout command is on macOS

Hi all,

I turned this into a script allowing for various of these behaviors to be configured via parameters.

I'm using it in our CI pipelines to make sure that APIs served by containers are alive before performing the next steps in the pipeline.

I'm very far from being a Bash expert and PR for improvements are very welcome.

Of course feel free the fork if you wish to :)

Thanks! Hope someone could make it to be a github action.

There is https://github.com/nev7n/wait_for_response, however, that doesn't support all the options available in curl.

Hi all,

Here a solution that worked to me. In my case I used it for an initContainer:

sh -c 'while (( curl -s -o /dev/null -w %{http_code} https://google.com/ != "200" && curl -s -o /dev/null -w %{http_code} https://google.com/ != "301")); do sleep 1; done;'

#!/bin/bash
set -eux

declare HOST=$1
declare STATUS=$2
declare TIMEOUT=$3

HOST=$HOST STATUS=$STATUS timeout --foreground -s TERM $TIMEOUT bash -c \
    'while [[ ${STATUS_RECEIVED} != ${STATUS} ]];\
        do STATUS_RECEIVED=$(curl -s -o /dev/null -L -w ''%{http_code}'' ${HOST}) && \
        echo "received status: $STATUS_RECEIVED" && \
        sleep 1;\
    done;
    echo success with status: $STATUS_RECEIVED'