pgspider Citus 集成使用

Citus 是一个很强大且成功的pg 扩展，以下是pgspider 集成Citus 的使用

docker镜像

FROM dalongrong/pgspider:base as build

WORKDIR /app

RUN apt-get update && apt-get install -y cmake automake autoconf libcurl4-openssl-dev libtool pkg-config libssl-dev

RUN git clone https://github.com/citusdata/citus.git /app/postgresql-11.6/contrib/citus

RUN cd /app/postgresql-11.6/contrib/citus && ./configure && make && make install

​

FROM debian:stretch-slim

ENV GOSU_VERSION 1.11

RUN apt-get update && apt-get install -y wget openssl libcurl4-openssl-dev libreadline-dev

# explicitly set user/group IDs

RUN set -eux; \

 groupadd -r postgres --gid=999; \

# https://salsa.debian.org/postgresql/postgresql-common/blob/997d842ee744687d99a2b2d95c1083a2615c79e8/debian/postgresql-common.postinst#L32-35

 useradd -r -g postgres --uid=999 --home-dir=/var/lib/postgresql --shell=/bin/bash postgres; \

# also create the postgres user's home directory with appropriate permissions

# see https://github.com/docker-library/postgres/issues/274

 mkdir -p /var/lib/postgresql; \

 chown -R postgres:postgres /var/lib/postgresql

​

RUN wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$(dpkg --print-architecture)" \

   && chmod +x /usr/local/bin/gosu \

   && gosu nobody true

# make the "en_US.UTF-8" locale so postgres will be utf-8 enabled by default

RUN set -eux; \

   if [ -f /etc/dpkg/dpkg.cfg.d/docker ]; then \

   # if this file exists, we're likely in "debian:xxx-slim", and locales are thus being excluded so we need to remove that exclusion (since we need locales)

   grep -q '/usr/share/locale' /etc/dpkg/dpkg.cfg.d/docker; \

   sed -ri '/\/usr\/share\/locale/d' /etc/dpkg/dpkg.cfg.d/docker; \

   ! grep -q '/usr/share/locale' /etc/dpkg/dpkg.cfg.d/docker; \

   fi; \

   apt-get update; apt-get install -y locales; rm -rf /var/lib/apt/lists/*; \

   localedef -i en_US -c -f UTF-8 -A /usr/share/locale/locale.alias en_US.UTF-8

ENV LANG en_US.utf8

​

# install "nss_wrapper" in case we need to fake "/etc/passwd" and "/etc/group" (especially for OpenShift)

# https://github.com/docker-library/postgres/issues/359

# https://cwrap.org/nss_wrapper.html

RUN set -eux; \

   apt-get update; \

   apt-get install -y --no-install-recommends libnss-wrapper; \

   rm -rf /var/lib/apt/lists/*

​

COPY --from=build /usr/local/pgspider /usr/local/pgspider

​

RUN sed -ri "s!^#?(listen_addresses)\s*=\s*\S+.*!\1 = '*'!" /usr/local/pgspider/share/postgresql/postgresql.conf.sample; \

   grep -F "listen_addresses = '*'" /usr/local/pgspider/share/postgresql/postgresql.conf.sample

RUN echo "shared_preload_libraries='citus'" >> /usr/local/pgspider/share/postgresql/postgresql.conf.sample

RUN mkdir -p /var/run/postgresql && chown -R postgres:postgres /var/run/postgresql && chmod 2777 /var/run/postgresql

ENV PATH $PATH:/usr/local/pgspider/bin

ENV PGDATA /var/lib/postgresql/data

RUN mkdir -p "$PGDATA" && chown -R postgres:postgres "$PGDATA" && chmod 777 "$PGDATA"

VOLUME /var/lib/postgresql/data

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

RUN ln -s usr/local/bin/docker-entrypoint.sh / # backwards compat

ENTRYPOINT ["docker-entrypoint.sh"]

​

EXPOSE 5432

CMD ["postgres"] 

环境准备

• docker-compose 文件

  没有使用官方的基于manger 自动添加节点的方式（官方是通过监听socket 对于label 自动处理worker 节点的上线以及下线）

version: "3"

services: 

  pg-citus-master:

    container_name: pg-citus-master

    image: dalongrong/pgspider:citus

    volumes: 

    - "./csvfiles:/opt/csv"

    ports: 

    - "5432:5432"

    environment: 

    - "POSTGRES_PASSWORD=dalong"

  pg-citus-worker:

    container_name: pg-citus-worker

    image: dalongrong/pgspider:citus

    volumes: 

    - "./csvfiles:/opt/csv"

    ports: 

    - "5433:5432"

• 启动

docker-compose up -d

使用Citus

注意因为使用的是社区版本，缺少用户的权限管理，简单的方式是对于mster节点配置密码，worker 节点不需要，但是会有安全风险（最好集群的安全控制）

• 创建扩展
  master 以及worker 都需要

 

create extension citus;

• 添加worker

SELECT master_add_node('pg-citus-worker', '5432');

• 创建表

CREATE TABLE companies (

    id bigint NOT NULL,

    name text NOT NULL,

    image_url text,

    created_at timestamp without time zone NOT NULL,

    updated_at timestamp without time zone NOT NULL

);

​

CREATE TABLE campaigns (

    id bigint NOT NULL,

    company_id bigint NOT NULL,

    name text NOT NULL,

    cost_model text NOT NULL,

    state text NOT NULL,

    monthly_budget bigint,

    blacklisted_site_urls text[],

    created_at timestamp without time zone NOT NULL,

    updated_at timestamp without time zone NOT NULL

);

​

CREATE TABLE ads (

    id bigint NOT NULL,

    company_id bigint NOT NULL,

    campaign_id bigint NOT NULL,

    name text NOT NULL,

    image_url text,

    target_url text,

    impressions_count bigint DEFAULT 0,

    clicks_count bigint DEFAULT 0,

    created_at timestamp without time zone NOT NULL,

    updated_at timestamp without time zone NOT NULL

);

​

ALTER TABLE companies ADD PRIMARY KEY (id);

ALTER TABLE campaigns ADD PRIMARY KEY (id, company_id);

ALTER TABLE ads ADD PRIMARY KEY (id, company_id);

• 下载数据
  下载到csvfiles 目录

 

curl https://examples.citusdata.com/tutorial/companies.csv > csvfiles/scompanies.csv

curl https://examples.citusdata.com/tutorial/campaigns.csv > csvfiles/campaigns.csv

curl https://examples.citusdata.com/tutorial/ads.csv > csvfiles/ads.csv

• 创建分布式表

SELECT create_distributed_table('companies', 'id');

SELECT create_distributed_table('campaigns', 'company_id');

SELECT create_distributed_table('ads', 'company_id');

• 导入数据
  容器内部操作，master 节点

 

\copy companies from 'companies.csv' with csv

\copy campaigns from 'campaigns.csv' with csv

\copy ads from 'ads.csv' with csv

• 数据查询

select * from ads;

效果

 

 

说明

以上是pgspider 与Citus 简单的集成，完备性测试还没有，不确定是否有bug

参考资料

https://hub.docker.com/r/citusdata/citus 
https://github.com/citusdata/citus 
https://hub.docker.com/repository/docker/dalongrong/pgspider 
https://github.com/rongfengliang/pgspider-docker 
https://github.com/rongfengliang/pgspider-citus-learning