x-yuri

docker: postgres: auth settings

There are three relevant environment variables: POSTGRES_USER, POSTGRES_DB, POSTGRES_PASSWORD. The first two determine username and database name of the superuser. Although postgres database is created in any case. Using POSTGRES_PASSWORD one can specify superuser password. Depending on presence or absence of the last one the init script decides the [authentication method][1] for all remote connection. With POSTGRES_PASSWORD it's md5, without trust (host all all all $authMethod).

x-yuri

In docker-compose.yml one can use variables either from environment, or from .env file. They don't automatically propagate into the containers. Variables added with env_file option are available only in the containers. environment option overrides values from env_file.

docker-compose.yml:

version: '3'

services:
  bash:

x-yuri

When docker is told to copy directory a to directory b, it copies contents of a into b. b and any of its parents might not exist:

FROM alpine

RUN mkdir src && touch src/f1

FROM alpine

x-yuri

Without either MONGO_INITDB_ROOT_USERNAME, or MONGO_INITDB_ROOT_PASSWORD the access is unrestricted.

docker-compose.yml:

version: '3'

services:
  mongo:
    image: mongo:4

x-yuri

UPD see https://gist.github.com/x-yuri/33fdc97fb46d097a50be1f9b7f551db8

Introduced in nodejs-12.11.0 (npm-6.11.3, 2019-09-25), npm-6.11.0, pacote-9.5.5. Affects nodejs-10.17.0, nodejs-12.13.0, nodejs-13.0.1.

$ docker-compose up

x-yuri

if (cluster.isMaster) {
  // ...
  // The important thing is that the master does very little,
  // increasing our resilience to unexpected errors.
  // ...
} else {
  // the worker
  //
 // This is where we put our bugs!

x-yuri

Let's prepare a stage for the experiments:

$ docker run --rm -it ruby:alpine sh
$ apk add build-base git
$ mkdir app
$ cd app
$ gem install bundler

$ gem list -e bundler

x-yuri

web-console: allow private networks

config/environments/development.rb:

require 'socket'
require 'ipaddr'
Rails.application.configure do
  ...
 config.web_console.permissions = Socket.getifaddrs

x-yuri

Running a site in production with Docker Compose

TODO

• pg: use superuser account (create extension)
• docker-compose.yml: prefer dicts over arrays
• docker-compose.yml: no explicit network is needed
• add UID variable
• .dockerignore
• docker-compose.yml: environment after env_file

x-yuri

Use ELECTRON_ENABLE_LOGGING=true.

index.js:

const { app, BrowserWindow } = require('electron');

function createWindow () {