containers Archives - Page 2 of 3

Posted on March 21, 2022May 20, 2022 by geralexgr — Leave a comment

Push multiple docker container images using a loop – Azure DevOps

On a pipeline that I was creating I wanted to push multiple docker images on an Azure container registry based on a list. In order to do that I used the docker@2 task on a loop providing the images that I had to push as a parameter. Code is attached below.

	trigger:
	– none

	pr: none

	parameters:
	– name: containerlist
	type: object
	default: ["core/image1","core/image2","core/image3","core/image4"]

	– name: DockerPushID
	type: string


	pool:
	name: demo-app


	stages:
	– stage: containers
	displayName: Push containers to container registry $(registry)
	jobs:
	– job: pushcontainers
	displayName: Push containers on testexample.azurecr.io

	steps:
	– checkout: none
	– ${{ each container in parameters.containerlist }}:
	– task: Docker@2
	displayName: pushing image ${{container}}
	inputs:
	containerRegistry: 'registryconnection'
	repository: '${{container}}'
	command: 'push'
	tags: \|
	current-${{parameters.DockerPushID}}
	current-latest

view raw azure devops – push multiple images on azure container registry hosted with ❤ by GitHub

This task will run steps based on the images you provide on the parameters list. An important note is that you need to have the image named accordingly in order to get a successful result. For example if you need to push on geralexgr.azurecr.io you will need to have your images named as below.

geralexgr.azurecr.io/image1:current-latest
geralexgr.azurecr.io/image2:current-latest

Else you may notice some failures indicating the below.

The push refers to repository [***/kati/image1] 
An image does not exist locally with the tag: ***/kati/image1

A successful run of the pipeline.

Additional information regarding loops and expressions on Azure DevOps pipelines:

https://docs.microsoft.com/en-us/azure/devops/pipelines/process/expressions?view=azure-devops#functions

Video tutorial on YouTube:

Posted on March 16, 2022March 16, 2022 by geralexgr — 2 Comments

Write blob file data on Azure storage account – C# .NET

In this article I will demonstrate how you can write a simple .NET console application to write data inside a blob container on an Azure storage account.

Storage accounts support the below four data structures.

For the cases of an application, I had to write every x seconds data on a file in order to get the coordinates of an app. For this purpose I selected a storage account container on which I will store the Latitude and Longitude in a .json format.

Inside my storage account I created a container which I will use named application.

Inside application container I created a file named locations.json. This will be the file that will get updated from the mobile app.

My console app consists of two .cs files. One is the location class which will be my model for the serialization.

   public class Location
    {
        public Double Latitude { get; set; }    
        public Double Longitude { get; set; }
    }

And the main code which consists of two functions. The RetrieveBlobContents function can read the stream content of a requested file from the blob. As I have specific names for my scenario, I hard coded them on the application. My containerName is application and the file which I want to read is called locations.json

The WriteContentOnBlob function will serialize a random Location object and will update the file every 5 seconds. The result is accomplished by writing a file locally and pushing this local file on the blob storage. The content of the file will be first extracted on the current directory/data folder.

Program.cs

	using System;
	using System.Threading.Tasks;
	using System.Configuration;
	using System.Collections.Generic;
	using System.Net;
	using System.Timers;
	using Azure.Storage.Blobs;
	using Azure.Storage.Blobs.Models;
	using System;
	using System.IO;
	using System.Threading.Tasks;
	using System.Text;
	using storageaccount;
	using Newtonsoft.Json;

	public class Program
	{
	public static readonly string BlobConnectionString = ""
	public static readonly string containerName = "application";
	public static readonly string fileName = "locations.json";




	static async Task Main(string[] args)
	{
	//await RetrieveBlobContents();

	while (true)
	{
	Thread.Sleep(5000);
	await WriteContentOnBlob();
	}

	}

	private static async Task RetrieveBlobContents()
	{
	BlobServiceClient blobServiceClient = new BlobServiceClient(BlobConnectionString);
	BlobContainerClient containerClient = blobServiceClient.GetBlobContainerClient(containerName);

	BlobClient blobClient = containerClient.GetBlobClient(fileName);

	var response = await blobClient.DownloadAsync();
	using (var streamReader = new StreamReader(response.Value.Content))
	{
	while (!streamReader.EndOfStream)
	{
	var line = await streamReader.ReadLineAsync();
	Console.WriteLine(line);
	}
	}

	}

	private static async Task WriteContentOnBlob()
	{
	BlobServiceClient blobServiceClient = new BlobServiceClient(BlobConnectionString);
	BlobContainerClient containerClient = blobServiceClient.GetBlobContainerClient(containerName);

	BlobClient blobClient = containerClient.GetBlobClient(fileName);

	Directory.CreateDirectory("./data");
	string localPath = "./data/";

	Random rnd = new Random();
	Double _longtitude = rnd.NextDouble();
	Double _latitude = rnd.NextDouble();

	Location blobLocation = new Location();
	blobLocation.Latitude = _latitude;
	blobLocation.Longitude = _longtitude;

	string json = JsonConvert.SerializeObject(blobLocation);
	//blobClient.write(json);

	string localFilePath = Path.Combine(localPath, fileName);
	await File.WriteAllTextAsync(localFilePath, json);
	await blobClient.UploadAsync(localFilePath, true);


	Console.WriteLine("Latitude: {0} Longtitude: {1} ",_latitude,_longtitude);

	}


	}

view raw azure-storageaccount-demo hosted with ❤ by GitHub

By running the application the values will be replaced every time on the locations.json file.

Posted on September 15, 2021September 16, 2021 by geralexgr — Leave a comment

Deploy wordpress with mysql in less than a minute using docker containers

For testing purposes I had to deploy a wordpress installation and perform some work. As the standalone installation with wamp/mamp/xampp software would require time, I chose docker and containers for the deployment.

You can use the below docker-compose.yml file and have a working site stack in less than a minute.

version: '3.1'

services:

  wordpress:
    image: wordpress
    restart: always
    ports:
      - 8080:80
    environment:
      WORDPRESS_DB_HOST: host.docker.internal
      WORDPRESS_DB_USER: root
      WORDPRESS_DB_PASSWORD: password
      WORDPRESS_DB_NAME: wordpress
    volumes:
      - wordpress:/var/www/html

  db:
    image: mysql:latest
    restart: always
    environment:
      MYSQL_DATABASE: wordpress
      MYSQL_USER: user1
      MYSQL_PASSWORD: password
      MYSQL_ROOT_PASSWORD: password
    ports:
      - 3306:3306
    volumes:
      - db:/var/lib/mysql

volumes:
  wordpress:
  db:

You can run the above composer file with:

docker compose up -d

In order to access the new wordpress installation you should go to 0.0.0.0:8080 or localhost:8080

You can clone the code from the below repository:

https://github.com/geralexgr/wordpress-mysql-containers/

Posted on May 21, 2021June 16, 2021 by geralexgr — Leave a comment

Create a CI/CD pipeline with Gitlab on container deployments

In order to create a CI/CD pipeline with gitlab built-in functionality you should firstly create the appropriate .gitlab-ci.yml file. This is the file on which the steps will be described for the pipeline.

This file should be placed on the root structure of the branch and every time a commit is pushed on the remote repository the steps will run. Instructions have been provided from gitlab and can be found here

For this example I chose gitlab runner as the building tool and the deployment method of a docker container.

In order to install gitlab runner as a container perform the below steps:

Download the image.

 docker run -d --name gitlab-runner --restart always \
     -v /srv/gitlab-runner/config:/etc/gitlab-runner \
     -v /var/run/docker.sock:/var/run/docker.sock \
     gitlab/gitlab-runner:latest

Create a persistent volume

docker volume create gitlab-runner-config

Stop the container if already started from previous step and run it again with the mapped volume

docker run -d --name gitlab-runner --restart always \     -v /var/run/docker.sock:/var/run/docker.sock \     -v gitlab-runner-config:/etc/gitlab-runner \     gitlab/gitlab-runner:latest

You will see the container running

Inspect container and press gitlab-runner register

Start the runner

gitlab-runner start

The runner should have been registered on your gitlab environment

Perform a commit and push changes to your repository

The run task should have started

Check the pipeline and see its status

The job was not succesful and by checking the logs I could verify that DNS resolution could not be enstablished.

In order to fix that you should add an entry for your named gitlab container to your gitlab runner. Unfortunately there are no tools like vim, nano installed on gitlab-runner. However you can bypass this by echoing a value in your /etc/hosts file.

It is also important that your local computer can resolve by fqdn your gitlab deployment. This is necessary because docker should be able to read this entry and perform actions on it.

After those changes you will be able to run your pipeline successfully.