docker自建elasticsearch镜像

　　一、dockerhub中没有elasticsearch:6.2.4版本的镜像（你敢信！！），没有办法只有自己弄了

　　二、参考官网镜像的构建过程(尼玛看不懂)

 　　备注：看不懂呀，不过有些过程还是可以了解的（比如创建用户和组啥的）

　　三、自己编写dockerfile(参考官网的执行过程)

FROM java:8
MAINTAINER lilin
RUN ln -sf /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
RUN mkdir -p /usr/share
RUN mkdir -p /usr/local/bin
ADD elasticsearch-6.2.4.tar.gz /usr/share/
ADD docker-entrypoint.sh /usr/local/bin
RUN mv /usr/share/elasticsearch-6.2.4 /usr/share/elasticsearch
RUN useradd elasticsearch
RUN usermod -G root elasticsearch
RUN chown -R elasticsearch:root /usr/share/elasticsearch
RUN chmod +x /usr/local/bin/docker-entrypoint.sh
ENTRYPOINT ["/usr/local/bin/docker-entrypoint.sh"]
CMD ["eswrapper"]

　　四、构建测试

docker build -t elasticsearch:6.2.4 .

　　五、测试

docker run -it elasticsearch:6.2.4 /bin/bash

　　容量内执行：

sh /usr/local/bin/docker-entrypoint.sh

 　　六、文件下载

　　elasticsearch:6.2.4:https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-6.2.4.tar.gz

　　docker-entrypoint.sh

#!/bin/bash
set -e

# Files created by Elasticsearch should always be group writable too
umask 0002

run_as_other_user_if_needed() {
  if [[ "$(id -u)" == "0" ]]; then
    # If running as root, drop to specified UID and run command
    exec chroot --userspec=1000 / "${@}"
  else
    # Either we are running in Openshift with random uid and are a member of the root group
    # or with a custom --user
    exec "${@}"
  fi
}

# Allow user specify custom CMD, maybe bin/elasticsearch itself
# for example to directly specify `-E` style parameters for elasticsearch on k8s
# or simply to run /bin/bash to check the image
if [[ "$1" != "eswrapper" ]]; then
  if [[ "$(id -u)" == "0" && $(basename "$1") == "elasticsearch" ]]; then
    # centos:7 chroot doesn't have the `--skip-chdir` option and
    # changes our CWD.
    # Rewrite CMD args to replace $1 with `elasticsearch` explicitly,
    # so that we are backwards compatible with the docs
    # from the previous Elasticsearch versions<6
    # and configuration option D:
    # https://www.elastic.co/guide/en/elasticsearch/reference/5.6/docker.html#_d_override_the_image_8217_s_default_ulink_url_https_docs_docker_com_engine_reference_run_cmd_default_command_or_options_cmd_ulink
    # Without this, user could specify `elasticsearch -E x.y=z` but
    # `bin/elasticsearch -E x.y=z` would not work.
    set -- "elasticsearch" "${@:2}"
    # Use chroot to switch to UID 1000
    exec chroot --userspec=1000 / "$@"
  else
    # User probably wants to run something else, like /bin/bash, with another uid forced (Openshift?)
    exec "$@"
  fi
fi

# Parse Docker env vars to customize Elasticsearch
#
# e.g. Setting the env var cluster.name=testcluster
#
# will cause Elasticsearch to be invoked with -Ecluster.name=testcluster
#
# see https://www.elastic.co/guide/en/elasticsearch/reference/current/settings.html#_setting_default_settings

declare -a es_opts

while IFS='=' read -r envvar_key envvar_value
do
  # Elasticsearch settings need to have at least two dot separated lowercase
  # words, e.g. `cluster.name`, except for `processors` which we handle
  # specially
  if [[ "$envvar_key" =~ ^[a-z0-9_]+\.[a-z0-9_]+ || "$envvar_key" == "processors" ]]; then
    if [[ ! -z $envvar_value ]]; then
      es_opt="-E${envvar_key}=${envvar_value}"
      es_opts+=("${es_opt}")
    fi
  fi
done < <(env)

# The virtual file /proc/self/cgroup should list the current cgroup
# membership. For each hierarchy, you can follow the cgroup path from
# this file to the cgroup filesystem (usually /sys/fs/cgroup/) and
# introspect the statistics for the cgroup for the given
# hierarchy. Alas, Docker breaks this by mounting the container
# statistics at the root while leaving the cgroup paths as the actual
# paths. Therefore, Elasticsearch provides a mechanism to override
# reading the cgroup path from /proc/self/cgroup and instead uses the
# cgroup path defined the JVM system property
# es.cgroups.hierarchy.override. Therefore, we set this value here so
# that cgroup statistics are available for the container this process
# will run in.
export ES_JAVA_OPTS="-Des.cgroups.hierarchy.override=/ $ES_JAVA_OPTS"

if [[ -f bin/elasticsearch-users ]]; then
  # Check for the ELASTIC_PASSWORD environment variable to set the
  # bootstrap password for Security.
  #
  # This is only required for the first node in a cluster with Security
  # enabled, but we have no way of knowing which node we are yet. We'll just
  # honor the variable if it's present.
  if [[ -n "$ELASTIC_PASSWORD" ]]; then
    [[ -f /usr/share/elasticsearch/config/elasticsearch.keystore ]] || (run_as_other_user_if_needed elasticsearch-keystore create)
    if ! (run_as_other_user_if_needed elasticsearch-keystore list | grep -q '^bootstrap.password$'); then
      (run_as_other_user_if_needed echo "$ELASTIC_PASSWORD" | elasticsearch-keystore add -x 'bootstrap.password')
    fi
  fi
fi

if [[ "$(id -u)" == "0" ]]; then
  # If requested and running as root, mutate the ownership of bind-mounts
  if [[ -n "$TAKE_FILE_OWNERSHIP" ]]; then
    chown -R 1000:0 /usr/share/elasticsearch/{data,logs}
  fi
fi

run_as_other_user_if_needed /usr/share/elasticsearch/bin/elasticsearch "${es_opts[@]}"