Kubenetes: Is it possible to hit multiple pods with a single request in Kubernetes cluster

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Provided you got kubectl in your pod and have access to the api-server, you can get all endpoint adressess and pass them to curl:

kubectl get endpoints <servicename> \
        -o jsonpath="{.subsets[*].addresses[*].ip}" | xargs curl

Alternative without kubectl in pod:

the recommended way to access the api server from a pod is by using kubectl proxy: https://kubernetes.io/docs/tasks/access-application-cluster/access-cluster/#accessing-the-api-from-a-pod this would of course add at least the same overhead. alternatively you could directly call the REST api, you’d have to provide the token manually.

APISERVER=$(kubectl config view --minify | grep server | cut -f 2- -d ":" | tr -d " ")
TOKEN=$(kubectl describe secret $(kubectl get secrets \
     | grep ^default | cut -f1 -d ' ') | grep -E '^token' | cut -f2 -d':' | tr -d " ")

if you provide the APISERVER and TOKEN variables, you don’t need kubectl in your pod, this way you only need curl to access the api server and “jq” to parse the json output:

curl $APISERVER/api/v1/namespaces/default/endpoints --silent \
     --header "Authorization: Bearer $TOKEN" --insecure \
     | jq -rM ".items[].subsets[].addresses[].ip" | xargs curl

UPDATE (final version)

APISERVER usually can be set to kubernetes.default.svc and the token should be available at /var/run/secrets/kubernetes.io/serviceaccount/token in the pod, so no need to provide anything manually:

TOKEN=$(cat /var/run/secrets/kubernetes.io/serviceaccount/token); \
curl https://kubernetes.default.svc/api/v1/namespaces/default/endpoints --silent \
     --header "Authorization: Bearer $TOKEN" --insecure \
     | jq -rM ".items[].subsets[].addresses[].ip" | xargs curl

jq is available here: https://stedolan.github.io/jq/download/ (< 4 MiB, but worth it for easily parsing JSON)

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