rgordeev

Combining two git repositories

Use case: You have repository A with remote location rA, and repository B (which may or may not have remote location rB). You want to do one of two things:

• preserve all commits of both repositories, but replace everything from A with the contents of B, and use rA as your remote location
• actually combine the two repositories, as if they are two branches that you want to merge, using rA as the remote location

NB: Check out git subtree/git submodule and this Stack Overflow question before going through the steps below. This gist is just a record of how I solved this problem on my own one day.

Before starting, make sure your local and remote repositories are up-to-date with all changes you need. The following steps use the general idea of changing the remote origin and renaming the local master branch of one of the repos in order to combine the two master branches.

rgordeev

package demo;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

import org.hibernate.annotations.GenericGenerator;
import org.hibernate.annotations.Parameter;
import org.springframework.boot.SpringApplication;

rgordeev

-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query 
FROM pg_stat_activity 
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' 
ORDER BY query_start desc;

-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query 
FROM pg_stat_activity 
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' 

rgordeev

# Base settings and GC logging
-server -XX:+AlwaysPreTouch  # First should be default, but we make it explicit, second pre-zeroes memory mapped pages on JVM startup -- improves runtime performance
# -Xloggc:gc-%t.log  # CUSTOMIZE LOCATION HERE - $path/gc-%t.log -- the %t in the gc log file path is so we get a new file with each JVM restart
-XX:NumberOfGCLogFiles=5 -XX:+UseGCLogFileRotation -XX:GCLogFileSize=20m # Limits the number of files, logs to folder 
-XX:+PrintGC -XX:+PrintGCDateStamps -XX:+PrintGCDetails -XX:+PrintHeapAtGC -XX:+PrintGCCause
-XX:+PrintTenuringDistribution -XX:+PrintReferenceGC -XX:+PrintAdaptiveSizePolicy # gather info on object age & reference GC time for further tuning if needed.

# G1 specific settings -- probably should be default for multi-core systems with >2 GB of heap (below that, default is probably fine)
-XX:+UseG1GC
-XX:+UseStringDeduplication

rgordeev

The initial source comes from sdcuike/issueBlog#4

http://greenteapress.com/wp/

https://papers.nips.cc

https://github.com/PacktPublishing free to download books code by Packet

https://love2.io Chinese site

rgordeev

Creating a Spring Boot Web (REST) service with SSL

We will refer to: https://github.com/jonashackt/spring-boot-rest-clientcertificate

Full project is available at: https://github.com/neolaw84/spring_boot_web_with_ssl

Situation/Problem

To create an SSL secured web (REST) service with cliet authentication (X509) using Spring Boot.

rgordeev

Virtual Hosts on nginx (CSC309)

When hosting our web applications, we often have one public IP address (i.e., an IP address visible to the outside world) using which we want to host multiple web apps. For example, one may wants to host three different web apps respectively for example1.com, example2.com, and example1.com/images on the same machine using a single IP address.

How can we do that? Well, the good news is Internet browsers

rgordeev

Features of Minio Server.

Item	Specification
Custom access key	environment MINIO_ACCESS_KEY
Custom secret key	environment MINIO_SECRET_KEY
Turn off web browser	environment MINIO_BROWSER=off
Listening on bucket notifications	using an extended S3 API
Support for bucket notifications	postgres, amqp, nats, elasticsearch, redis, kafka (in-progress)
Shared Backend (FS)	In-progress

rgordeev

Thinking Architecturally

Source Resources

• Thinking Architecturally - Nathaniel Schutta - youtube
• Thinking Architecturally: Lead Technical Change Within Your Engineering Team - oreilly book
• Infrastructure & Ops Superstream Series: CI/CD - oreilly video
• Building Evolutionary Architectures - oreilly book

Notes (Thinking Architecturally - Nathaniel Schutta youtube video)

rgordeev

Установка Outline VPN на Ubuntu 20.04

Outline VPN - это бесплатный инструмент с открытым исходным кодом, позволяющий развернуть собственную VPN на Вашем собственном сервере или на машине облачного провайдера. Подробную информацию Вы можете узнать здесь и здесь.

В своем составе имеет как графические инструменты, так и средства работы через командную строку. Позволяет использовать VPN как на настольных компьютерах, так и на мобильных устройствах.

Прежде чем начать

Вам нужен сервер. Да, его нужно арендовать, учитывая его местоположение. Например, если Вам нужно получать доступ к ресурсам, которые недоступны в текущем местоположении, но доступны, например, в Канаде, то смело арендуйте виртуальную машину в AWS, Digital Ocean или любом другом месте.