Docker with Postgres

Everyone has an start and I feel this is one of the ways. There is the code

Goal

Create an postgres with some data load in there.

Data

For this purpouse it's going to be use this dataset. In there we could find two csv:

• 1st File: Travel Company Old Clients; Number of observations: 682
• 2nd File: Travel Company New Clients; Number of observations: 1303

We are going to use only Travel Company New Clients.

Prequistes

• Docker version 23.0.5
• Postgres version 15

1- Create a docker-compose

For this objective we are going to create an image based on actual image

version: '3.9'
services:
  post_db:
    build: . 
    image: postgres/test:v1
    user: postgres
    environment:
      - POSTGRES_USER=${PS_USER}
      - POSTGRES_PASSWORD=${PS_PASSWORD}
      - PG_DATA:/var/lib/postgresql/data/pgdata
      - POSTGRES_DB=${PS_DB}
    healthcheck:
      test: ["CMD-SHELL","pg_isready -U ${PS_USER} ${PS_PASSWORD}"]
      interval: 10s
      timeout: 5s
      retries: 5
    ports:
      - "8080:8080"
    volumes:
      - db-data:/var/lib/postgresql/data
    restart: unless-stopped
volumes:
  db-data: 

There are a healthcheck to view if there are something wrong with the connection.

2 - Create table(s)

If we want to create a table as init configuration. The scrips shouldbe place in docker-entrypoint-initdb.d.

There is an example of script in bash:

!/bin/bash

set -e


psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" --dbname "$POSTGRES_DB" <<-EOSQL

CREATE TABLE 
    newClients (
         Num_Age INT
        ,Des_EmployeType VARCHAR(50)
        ,Is_Graduate VARCHAR(3)
        ,Imp_AnnualIncome INT
        ,Num_FamilyMembers INT
        ,Num_ChronicDisease INT
        ,Is_FrequentFlyer VARCHAR(3)
        ,Is_EverTravelledAbroad VARCHAR(3)
    );
EOSQL

Also, it should be place in the Dockerfile.

FROM postgres${PS_VERSION}

# make directory to Docker
RUN mkdir -p /home/raw

# copy scripts
COPY ./raw/* /docker-entrypoint-initdb.d

# run all the scripts in initdb
RUN chmod a+r /docker-entrypoint-initdb.d/*

3- Load data

Now, with the folder of docker-entrypoint-initdb it could be use to load the data adding in the last script:

#!/bin/bash

set -e


psql -v ON_ERROR_STOP=1 --username "$POSTGRES_USER" --dbname "$POSTGRES_DB" <<-EOSQL

CREATE TABLE 
    newClients (
         Num_Age INT
        ,Des_EmployeType VARCHAR(100)
        ,Is_Graduate VARCHAR(3)
        ,Imp_AnnualIncome INT
        ,Num_FamilyMembers INT
        ,Num_ChronicDisease INT
        ,Is_FrequentFlyer VARCHAR(3)
        ,Is_EverTravelledAbroad VARCHAR(3)
    );

COPY newClients FROM '/home/src/Travel Company New Clients.csv' DELIMITER ';' CSV HEADER;
EOSQL

And it's looks like it works.

If there are any kind of improvment or a better practise please let me know, and I will fix it.