MichalAdorno

package main

import (
	"database/sql/driver"
	"encoding/json"

	"github.com/jinzhu/gorm"
	_ "github.com/lib/pq"
)

MichalAdorno

//Contents from https://spring.io/understanding/CORS 

In the simplest scenario, cross-origin communications starts with a client making a GET, POST, or HEAD request against a resource on the server.
In this scenario, the content type of a POST request is limited to application/x-www-form-urlencoded, multipart/form-data, or text/plain. The request includes an Origin header that indicates the origin of the client code.

The server will consider the request's Origin and either allow or disallow the request. If the server allows the request, then it will respond with the requested resource and an Access-Control-Allow-Origin header in the response. This header will indicate to the client which client origins will be allowed to access the resource. Assuming that the Access-Control-Allow-Origin header matches the request's Origin, the browser will allow the request.

On the other hand, if Access-Control-Allow-Origin is missing in the response or if it doesn't match the request's Origin, the browser will disallow th

MichalAdorno

version: "3"
services:
  postgress:
  ....
    healthcheck:
      test: ["CMD-SHELL", "pg_isready -U postgres"]
      interval: 10s
      timeout: 5s
      retries: 5
  app:

MichalAdorno

# Redis Cheatsheet
# All the commands you need to know


redis-server /path/redis.conf  # start redis with the related configuration file
redis-cli                      # opens a redis prompt


# Strings.

MichalAdorno

/*
@MockBean //or Mockito's @Mock
- it mocks the object and all its methods with do nothing and their result value will be null,
- use for example: when(...) methods to create mocked method behaviour
- use when you want to completely get rid of the object's normal behaviour
- caution: unmocked methods won't work -> can result in a RuntimeException during tests (@SpyBean is a remedy here apart from wider mocking)
@SpyBean //or Mockito's @Spy
- an object will behave like an @Autowired object
- all its methods will actually works, but we can define some custom behavior for its methods 
- use doReturn(...) / doNothing(...) to add custom (mocked) method behaviour 

MichalAdorno

//--------------------------------------------------------
//Service that we want to execute asynchroneously - consists of the following method:
public String execute() {
    try {
        Thread.sleep(5000);
        logger.info("Slow task executed");
        return "Task finished";
    } catch (InterruptedException e) {
        throw new RuntimeException();
    }

MichalAdorno

GetMapping("/async-deferredresult")
public DeferredResult<ResponseEntity<?>> handleReqDefResult(Model model) {
    LOG.info("Received async-deferredresult request");
    DeferredResult<ResponseEntity<?>> output = new DeferredResult<>(); //just a declaration
     
    ForkJoinPool.commonPool().submit(() -> {        //we pass a service method to an ExecutorService / thread pool
        LOG.info("Processing in separate thread");
        try {
            Thread.sleep(6000);
        } catch (InterruptedException e) {

MichalAdorno

import java.io.IOException;
import java.net.URLClassLoader;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.nio.file.Path;

/**
 * Example demonstrating a ClassLoader leak.
 *
 * <p>To see it in action, copy this file to a temp directory somewhere,

MichalAdorno

<project>
...
    <build>
        <plugins>
            <plugin>
                <groupId>org.jacoco</groupId>
                <artifactId>jacoco-maven-plugin</artifactId>
                <executions>
                    <execution>
                        <id>default-prepare-agent</id>