kube-backup

#!/bin/bash -e

# Based on https://github.com/pieterlange/kube-backup
# Original Copyright
# The MIT License (MIT)
#
# Copyright (c) 2016 Pieter Lange
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.

set -eo pipefail
export LC_ALL=C
unset CDPATH

THIS_DIR=$( (cd "$(dirname -- "${BASH_SOURCE[0]}")" && pwd -P))

# shellcheck source=kube-shlib.sh
source "$THIS_DIR/kube-shlib.sh"

define-kubectl-funcs

# Defaults
DEFAULT_RESOURCETYPES="ingress deployment configmap svc rc ds networkpolicy statefulset cronjob pvc secret"
DEFAULT_GLOBALRESOURCES="namespace storageclass clusterrole clusterrolebinding customresourcedefinition persistentvolume"

DEST_DIR=$PWD
NAMESPACES=
RESOURCETYPES=
GLOBALRESOURCES=
INCLUDE_TILLER_CONFIGMAPS=

usage() {
    echo "Backup Kubernetes state to set of YAML files"
    echo "Based on https://github.com/pieterlange/kube-backup"
    echo
    echo "$(basename "$0") [options] [dest-dir]"
    echo ""
    echo "When dest-dir is not specified current directory is used ($PWD)"
    echo ""
    echo "environment variables:"
    echo "  KUBECTL                    Name of the kubectl command to use"
    echo "  KUBECTL_BIN                Full path to the kubectl binary. This variable has precedence over KUBECTL"
    echo "  KUBE_CONTEXT               The name of the kubeconfig context to use"
    echo "  KUBECTL_OPTS               Additional options for kubectl"
    echo ""
    echo "options:"
    echo "  -c, --context              The name of the kubeconfig context to use."
    echo "                             Has precedence over KUBE_CONTEXT variable."
    echo "  -n, --namespace(s)=        Namespaces to backup separted by spaces."
    echo "                             Multiple namespace arguments are concatenated"
    echo "  -r, --resourcetype(s)=     Resource types to backup separted by spaces."
    echo "                             Multiple resourcetype arguments are concatenated"
    echo "  -g, --globalresource(s)=   Global resources to backup separted by spaces."
    echo "                             Multiple global resource arguments are concatenated"
    echo "      --include-tiller-configmaps"
    echo "                             Include Tiller configmaps into backup"
    echo "      --help                 Display this help and exit"
    echo "      --                     End of options"
}

while [[ $# -gt 0 ]]; do
    case "$1" in
    -c | --context)
        KUBE_CONTEXT="$2"
        shift 2
        ;;
    --context=*)
        KUBE_CONTEXT="${1#*=}"
        shift
        ;;
    -n | --namespace | --namespaces)
        NAMESPACES="$NAMESPACES $2"
        shift 2
        ;;
    --namespace=* | --namespaces=*)
        NAMESPACES="$NAMESPACES ${1#*=}"
        shift
        ;;
    -r | --resourcetype | --resourcetypes)
        RESOURCETYPES="$RESOURCETYPES $2"
        shift 2
        ;;
    --resourcetype=* | --resourcetypes=*)
        RESOURCETYPES="$RESOURCETYPES ${1#*=}"
        shift
        ;;
    -g | --globalresource | --globalresources)
        GLOBALRESOURCES="$GLOBALRESOURCES $2"
        shift 2
        ;;
    --globalresource=* | --globalresources=*)
        GLOBALRESOURCES="$GLOBALRESOURCES ${1#*=}"
        shift
        ;;
    --include-tiller-configmaps)
        INCLUDE_TILLER_CONFIGMAPS=true
        shift
        ;;
    --help)
        usage
        exit
        ;;
    --)
        shift
        break
        ;;
    -*)
        fatal "Unknown option $1"
        ;;
    *)
        break
        ;;
    esac
done

if [[ $# -gt 1 ]]; then
    fatal "Too many arguments"
fi

if [[ $# -eq 1 ]]; then
    DEST_DIR=$1
fi

if [ -n "$(ls -A "$DEST_DIR" 2>/dev/null)" ]; then
    echo "Error: Directory $DEST_DIR is not empty !" >&2
    exit 1
fi

DEFAULT_RESOURCETYPES=$(run-kubectl-ctx api-resources --namespaced=true -o name)
DEFAULT_GLOBALRESOURCES=$(run-kubectl-ctx api-resources --namespaced=false -o name)

if [[ -z "$NAMESPACES" ]]; then
    NAMESPACES=$(run-kubectl-ctx get ns -o 'jsonpath={.items[*].metadata.name}')
fi
if [[ -z "$RESOURCETYPES" ]]; then
    RESOURCETYPES=$DEFAULT_RESOURCETYPES
fi
if [[ -z "$GLOBALRESOURCES" ]]; then
    GLOBALRESOURCES=$DEFAULT_GLOBALRESOURCES
fi

echo "Destination directory:      $DEST_DIR"
if [[ -n "$KUBE_CONTEXT" ]]; then
    echo "Kubectl context:            $KUBE_CONTEXT"
else
    echo "Kubectl context:            current ( $(kube-current-context) )"
fi
echo "Namespaces to backup:       $NAMESPACES"
echo "Resource types to backup:   $RESOURCETYPES"
echo "Global resources to backup: $GLOBALRESOURCES"

mkdir -p "$DEST_DIR"

# Start kubernetes state export
for resource in $GLOBALRESOURCES; do
    echo "Exporting resource: ${resource}" >/dev/stderr
    res_js=$(run-kubectl-ctx get -o=json "$resource") || continue

    jq --sort-keys \
        'del(
          .metadata.resourceVersion,
          .metadata.selfLink,
          .items[].metadata.annotations."kubectl.kubernetes.io/last-applied-configuration",
          .items[].metadata.annotations."control-plane.alpha.kubernetes.io/leader",
          .items[].metadata.uid,
          .items[].metadata.selfLink,
          .items[].metadata.resourceVersion,
          .items[].metadata.creationTimestamp,
          .items[].metadata.generation,
          .items[].spec.claimRef.resourceVersion
      )' <<<"$res_js" | python -c 'import sys, yaml, json; yaml.safe_dump(json.load(sys.stdin), sys.stdout, default_flow_style=False)' >"$DEST_DIR/${resource}.yaml"
done

for namespace in $NAMESPACES; do
    [ -d "$DEST_DIR/${namespace}" ] || mkdir -p "$DEST_DIR/${namespace}"

    for type in $RESOURCETYPES; do
        echo "[${namespace}] Exporting resources: ${type}" >/dev/stderr

        label_selector=""
        if [[ "$type" == 'configmap' && -z "${INCLUDE_TILLER_CONFIGMAPS:-}" ]]; then
            label_selector="-l OWNER!=TILLER"
        fi

        res_list=$(run-kubectl-ctx --namespace="${namespace}" get "$type" $label_selector -o custom-columns=SPACE:.metadata.namespace,KIND:..kind,NAME:.metadata.name --no-headers) || continue

        while read -r a b name; do
            [ -z "$name" ] && continue

            # Service account tokens cannot be exported
            if [[ "$type" == 'secret' && $(run-kubectl-ctx get -n "${namespace}" -o jsonpath="{.type}" secret "$name") == "kubernetes.io/service-account-token" ]]; then
                continue
            fi

            run-kubectl-ctx --namespace="${namespace}" get -o=json "$type" "$name" | jq --sort-keys \
                'del(
            .metadata.annotations."control-plane.alpha.kubernetes.io/leader",
            .metadata.annotations."kubectl.kubernetes.io/last-applied-configuration",
            .metadata.creationTimestamp,
            .metadata.generation,
            .metadata.resourceVersion,
            .metadata.selfLink,
            .metadata.uid,
            .spec.clusterIP,
            .status
            )' | python -c 'import sys, yaml, json; yaml.safe_dump(json.load(sys.stdin), sys.stdout, default_flow_style=False)' >"$DEST_DIR/${namespace}/${name}.${type}.yaml"
        done <<<"$res_list"
    done
done