#!/bin/bash

# Copyright 2014 The Kubernetes Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# Validates that the cluster is healthy.
# Error codes are:
# 0 - success
# 1 - fatal (cluster is unlikely to work)
# 2 - non-fatal (encountered some errors, but cluster should be working correctly)

set -o errexit
set -o nounset
set -o pipefail

setvar KUBE_ROOT = "$(dirname "${BASH_SOURCE}")/.."

if test -f "${KUBE_ROOT}/cluster/env.sh" {
  source "${KUBE_ROOT}/cluster/env.sh"
}

source "${KUBE_ROOT}/hack/lib/util.sh"
source "${KUBE_ROOT}/cluster/kube-util.sh"

# Run kubectl and retry upon failure.
proc kubectl_retry {
  setvar tries = '3'
  while ! "${KUBE_ROOT}/cluster/kubectl.sh" @ARGV {
    setvar tries = $((tries-1))
    if [[ ${tries} -le 0 ]] {
      echo "('kubectl $[join(ARGV)]' failed, giving up)" >&2
      return 1
    }
    echo "(kubectl failed, will retry ${tries} times)" >&2
    sleep 1
  }
}

setvar ALLOWED_NOTREADY_NODES = "${ALLOWED_NOTREADY_NODES:-0}"
setvar CLUSTER_READY_ADDITIONAL_TIME_SECONDS = "${CLUSTER_READY_ADDITIONAL_TIME_SECONDS:-30}"

setvar EXPECTED_NUM_NODES = "${NUM_NODES}"

if [[ "${KUBERNETES_PROVIDER:-}" == "gce" ]] {
  echo "Validating gce cluster, MULTIZONE=${MULTIZONE:-}"
  # In multizone mode we need to add instances for all nodes in the region.
  if [[ "${MULTIZONE:-}" == "true" ]] {
    setvar EXPECTED_NUM_NODES = $(gcloud -q compute instances list --project="${PROJECT}" --format=[no-heading] \
      --filter="name ~ '${NODE_INSTANCE_PREFIX}.*' AND zone:($(gcloud -q compute zones list --project="${PROJECT}" --filter=region=${REGION} --format=csv[no-heading]\(name\) | tr "\n" "," | sed  "s/,$//"))" | wc -l)
    echo "Computing number of nodes, NODE_INSTANCE_PREFIX=${NODE_INSTANCE_PREFIX}, REGION=${REGION}, EXPECTED_NUM_NODES=${EXPECTED_NUM_NODES}"
  }
}

if [[ "${REGISTER_MASTER_KUBELET:-}" == "true" ]] {
  if [[ "${KUBERNETES_PROVIDER:-}" == "gce" ]] {
    setvar NUM_MASTERS = $(get-master-replicas-count)
  } else {
    setvar NUM_MASTERS = '1'
  }
  setvar EXPECTED_NUM_NODES = $((EXPECTED_NUM_NODES+NUM_MASTERS))
}

setvar REQUIRED_NUM_NODES = $((EXPECTED_NUM_NODES - ALLOWED_NOTREADY_NODES))
# Make several attempts to deal with slow cluster birth.
setvar return_value = '0'
setvar attempt = '0'
# Set the timeout to ~25minutes (100 x 15 second) to avoid timeouts for 1000-node clusters.
setvar PAUSE_BETWEEN_ITERATIONS_SECONDS = '15'
setvar MAX_ATTEMPTS = '100'
setvar ADDITIONAL_ITERATIONS = $(((CLUSTER_READY_ADDITIONAL_TIME_SECONDS + PAUSE_BETWEEN_ITERATIONS_SECONDS - 1)/PAUSE_BETWEEN_ITERATIONS_SECONDS))
while true {
  # Pause between iterations of this large outer loop.
  if [[ ${attempt} -gt 0 ]] {
    sleep 15
  }
  setvar attempt = $((attempt+1))

  # The "kubectl get nodes -o template" exports node information.
  #
  # Echo the output and gather 2 counts:
  #  - Total number of nodes.
  #  - Number of "ready" nodes.
  #
  # Suppress errors from kubectl output because during cluster bootstrapping
  # for clusters where the master node is registered, the apiserver will become
  # available and then get restarted as the kubelet configures the docker bridge.
  #
  # We are assigning the result of kubectl_retry get nodes operation to the res
  # varaible in that way, to prevent stopping the whole script on an error.
  setvar node = $(kubectl_retry get nodes) && setvar res = """$?" || setvar res = """$?"
  if test ${res} -ne "0" {
    if [[ "${attempt}" -gt "${last_run:-$MAX_ATTEMPTS}" ]] {
      echo -e "${color_red} Failed to get nodes.${color_norm}"
      exit 1
    } else {
      continue
    }
  }
  setvar found = $(($(echo "${node}" | wc -l) - 1))
  setvar ready = $(($(echo "${node}" | grep -v "NotReady" | wc -l ) - 1))

  if (( "${found}" == "${EXPECTED_NUM_NODES}" )) && (( "${ready}" == "${EXPECTED_NUM_NODES}")) {
    break
  } elif (( "${found}" > "${EXPECTED_NUM_NODES}" )) {
    if [[ "${KUBE_USE_EXISTING_MASTER:-}" != "true" ]] {
      echo -e "${color_red}Found ${found} nodes, but expected ${EXPECTED_NUM_NODES}. Your cluster may not behave correctly.${color_norm}"
    }
    break
  } elif (( "${ready}" > "${EXPECTED_NUM_NODES}")) {
    echo -e "${color_red}Found ${ready} ready nodes, but expected ${EXPECTED_NUM_NODES}. Your cluster may not behave correctly.${color_norm}"
    break
  } else {
    if [[ "${REQUIRED_NUM_NODES}" -le "${ready}" ]] {
      echo -e "${color_green}Found ${REQUIRED_NUM_NODES} Nodes, allowing additional ${ADDITIONAL_ITERATIONS} iterations for other Nodes to join.${color_norm}"
      setvar last_run = "${last_run:-$((attempt + ADDITIONAL_ITERATIONS - 1))}"
    }
    if [[ "${attempt}" -gt "${last_run:-$MAX_ATTEMPTS}" ]] {
      echo -e "${color_yellow}Detected ${ready} ready nodes, found ${found} nodes out of expected ${EXPECTED_NUM_NODES}. Your cluster may not be fully functional.${color_norm}"
      kubectl_retry get nodes
      if [[ "${REQUIRED_NUM_NODES}" -gt "${ready}" ]] {
        exit 1
      } else {
        setvar return_value = '2'
        break
      }
    } else {
      echo -e "${color_yellow}Waiting for ${EXPECTED_NUM_NODES} ready nodes. ${ready} ready nodes, ${found} registered. Retrying.${color_norm}"
    }
  }
}
echo "Found ${found} node(s)."
kubectl_retry get nodes

setvar attempt = '0'
while true {
  # The "kubectl componentstatuses -o template" exports components health information.
  #
  # Echo the output and gather 2 counts:
  #  - Total number of componentstatuses.
  #  - Number of "healthy" components.
  setvar cs_status = $(kubectl_retry get componentstatuses -o template --template='{{range .items}}{{with index .conditions 0}}{{.type}}:{{.status}}{{end}}{{"\n"}}{{end}}') || true
  setvar componentstatuses = $(echo "${cs_status}" | grep -c 'Healthy:') || true
  setvar healthy = $(echo "${cs_status}" | grep -c 'Healthy:True') || true

  if ((componentstatuses > healthy)) || ((componentstatuses == 0)) {
    if ((attempt < 5)) {
      echo -e "${color_yellow}Cluster not working yet.${color_norm}"
      setvar attempt = $((attempt+1))
      sleep 30
    } else {
      echo -e " ${color_yellow}Validate output:${color_norm}"
      kubectl_retry get cs
      echo -e "${color_red}Validation returned one or more failed components. Cluster is probably broken.${color_norm}"
      exit 1
    }
  } else {
    break
  }
}

echo "Validate output:"
kubectl_retry get cs || true
if test ${return_value} == "0" {
  echo -e "${color_green}Cluster validation succeeded${color_norm}"
} else {
  echo -e "${color_yellow}Cluster validation encountered some problems, but cluster should be in working order${color_norm}"
}

exit "${return_value}"