Merge pull request #212 from zalando-incubator/run-local

Add a script to run operator locally

run_operator_locally.sh

@@ -0,0 +1,226 @@
+#!/usr/bin/env bash
+#
+# Deploy a Postgres operator to a minikube aka local Kubernetes cluster
+# Optionally re-build the operator binary beforehand to test local changes
+
+
+# enable unofficial bash strict mode
+set -o errexit
+set -o nounset
+set -o pipefail
+IFS=$'\n\t'
+
+
+readonly PATH_TO_LOCAL_OPERATOR_MANIFEST="/tmp/local-postgres-operator-manifest.yaml"
+readonly PATH_TO_PORT_FORWARED_KUBECTL_PID="/tmp/kubectl-port-forward.pid"
+readonly LOCAL_PORT="8080"
+readonly OPERATOR_PORT="8080"
+
+
+# minikube needs time to create resources,
+# so the script retries actions until all the resources become available
+function retry(){
+
+    local -r retry_cmd="$1"
+    local -r retry_msg="$2"
+
+    # times out after 1 minute
+    for i in {1..20}; do
+        if  eval "$retry_cmd"; then
+            return 0
+        fi
+        echo "$retry_msg"
+        sleep 3
+    done
+
+    >2& echo "The command $retry_cmd timed out"
+    return 1
+}
+
+
+function display_help(){
+    echo "Usage: $0 [ -r | --rebuild-operator ] [ -h | --help ]"
+}
+
+
+function clean_up(){
+
+    echo "==== CLEAN UP PREVIOUS RUN ==== "
+
+    local status
+    status=$(minikube status --format "{{.MinikubeStatus}}" || true)
+
+    if [[ "$status" = "Running" ]] || [[ "$status" = "Stopped" ]]; then
+        echo "Delete the existing local cluster so that we can cleanly apply resources from scratch..."
+        minikube delete
+    fi
+
+    if [[ -e "$PATH_TO_LOCAL_OPERATOR_MANIFEST" ]]; then
+        rm --verbose "$PATH_TO_LOCAL_OPERATOR_MANIFEST"
+    fi
+
+    # the kubectl process does the port-forwarding between operator and local ports
+    # we restart the process to bind to the same port again (see end of script)
+    if [[ -e "$PATH_TO_PORT_FORWARED_KUBECTL_PID" ]]; then
+
+        local pid
+        pid=$( < "$PATH_TO_PORT_FORWARED_KUBECTL_PID")
+
+        # the process dies if a minikube stops between two invocations of the script
+        if kill "$pid" > /dev/null  2>&1; then
+            echo "Kill the kubectl process responsible for port forwarding for minikube so that we can re-use the same ports for forwarding later..."
+        fi
+        rm --verbose  "$PATH_TO_PORT_FORWARED_KUBECTL_PID"
+
+    fi
+}
+
+
+function start_minikube(){
+
+    echo "==== START MINIKUBE ==== "
+    echo "May take a few minutes ..."
+
+    minikube start
+    kubectl config set-context minikube
+
+    echo "==== MINIKUBE STATUS ==== "
+    minikube status
+
+}
+
+
+function build_operator_binary(){
+
+    # redirecting stderr greatly reduces non-informative output during normal builds
+    echo "Build operator binary (stderr redirected to /dev/null)..."
+    make tools deps local > /dev/null 2>&1
+
+}
+
+
+function deploy_self_built_image() {
+
+    echo "==== DEPLOY CUSTOM OPERATOR IMAGE ==== "
+
+    build_operator_binary
+
+    # the fastest way to run a docker image locally is to reuse the docker from minikube
+    # set docker env vars so that docker can talk to the Docker daemon inside the minikube
+    eval $(minikube docker-env)
+
+    # image tag consists of a git tag or a unique commit prefix
+    # and the "-dev" suffix if there are uncommited changes in the working dir
+    local -x TAG
+    TAG=$(git describe --tags --always --dirty="-dev")
+    readonly TAG
+
+    # build the image
+    make docker > /dev/null 2>&1
+
+    # update the tag in the postgres operator conf
+    # since the image with this tag already exists on the machine,
+    # docker should not attempt to fetch it from the registry due to imagePullPolicy
+    sed --expression "s/\(image\:.*\:\).*$/\1$TAG/" manifests/postgres-operator.yaml > "$PATH_TO_LOCAL_OPERATOR_MANIFEST"
+
+    retry "kubectl create -f \"$PATH_TO_LOCAL_OPERATOR_MANIFEST\"" "attempt to create $PATH_TO_LOCAL_OPERATOR_MANIFEST resource"
+}
+
+
+function start_operator(){
+
+    echo "==== START OPERATOR ==== "
+    echo "Certain operations may be retried multiple times..."
+
+    # the order of resource initialization is significant
+    local file
+    for file  in "configmap.yaml" "serviceaccount.yaml"
+    do
+        retry "kubectl  create -f manifests/\"$file\"" "attempt to create $file resource"
+    done
+
+    if [[ "$should_build_custom_operator" = true ]]; then # set in main()
+        deploy_self_built_image
+    else
+        retry "kubectl  create -f manifests/postgres-operator.yaml" "attempt to create /postgres-operator.yaml resource"
+    fi
+
+    local -r msg="Wait for the postgresql custom resource definition to register..."
+    local -r cmd="kubectl get crd | grep --quiet 'postgresqls.acid.zalan.do'"
+    retry "$cmd" "$msg "
+
+    kubectl create -f manifests/complete-postgres-manifest.yaml
+}
+
+
+function forward_ports(){
+
+    echo "==== FORWARD OPERATOR PORT $OPERATOR_PORT TO LOCAL PORT $LOCAL_PORT  ===="
+
+    local operator_pod
+    operator_pod=$(kubectl get pod -l name=postgres-operator -o jsonpath={.items..metadata.name})
+
+    # runs in the background to keep current terminal responsive
+    # stdout redirect removes the info message about forwarded ports; the message sometimes garbles the cli prompt
+    kubectl port-forward "$operator_pod" "$LOCAL_PORT":"$OPERATOR_PORT" &> /dev/null &
+
+    echo $! > "$PATH_TO_PORT_FORWARED_KUBECTL_PID"
+}
+
+
+function check_health(){
+
+    echo "==== RUN HEALTH CHECK ==== "
+
+    local -r check_cmd="curl --location --silent --output /dev/null http://127.0.0.1:$LOCAL_PORT/clusters"
+    local -r check_msg="Wait for port forwarding to take effect"
+    echo "Command for checking: $check_cmd"
+
+    if  retry "$check_cmd" "$check_msg"; then
+        echo "==== SUCCESS: OPERATOR IS RUNNING ==== "
+        echo "To stop it cleanly, run 'minikube delete'"
+    else
+        >2& echo "==== FAILURE: OPERATOR DID NOT START OR PORT FORWARDING DID NOT WORK"
+        exit 1
+    fi
+}
+
+
+function main(){
+
+    if ! [[ $(basename "$PWD") == "postgres-operator" ]]; then
+        echo "Please execute the script only from the root directory of the Postgres opepator repo."
+        exit 1
+    fi
+
+    trap "echo 'If you observe issues with minikube VM not starting/not proceeding, consider deleting the .minikube dir and/or rebooting before re-running the script'" EXIT
+
+    local should_build_custom_operator=false # used in start_operator()
+    while true
+    do
+        # if the 1st param is unset, use the empty string as a default value
+        case "${1:-}" in
+            -h | --help)
+                display_help
+                exit 0
+                ;;
+            -r | --rebuild-operator)
+                should_build_custom_operator=true
+                break
+                ;;
+            *)  break
+                ;;
+        esac
+    done
+
+    clean_up
+    start_minikube
+    start_operator
+    forward_ports
+    check_health
+
+    exit 0
+}
+
+
+main "$@"