Am newbie to Spring boot. I need to create micro services and need to run by docker. I have attached my project structure here. Problem which is every time i need to up the micro services manually. For example am having 4 micro services and i just up this services manually. But all micro services should be started itself when deploying into docker. How to achieve this.
Also am using Cassandra database.
I don't know if it is the best solution, but it is the one i used:
First say to the spring boot maven plugin to create an executable jar :
<configuration>
<executable>true</executable>
</configuration>
After that you can add your application as a service in init.d and make it start when the container starts.
You can find a better explaination here : http://www.baeldung.com/spring-boot-app-as-a-service
Please have a look at the numerous tutorials that exists for spring boot and dockerizing this application.
Here is one which explains every step that is necessary
Build Application as Jar File
Create your docker image with Dockerfile
In this dockerfile you create an environment like you would have a new setup linux server and you define what you need for software to run your application: like java. Have a look at existing images like anapsix/alpine-java.
Now think of what you need to do to start your app in this environment: java -jar --some-options -location-of-your-jar.jar
Make sure to be able to reach your app by exposing the docker port so that you can see that is runs.
As I sad if these instruction is not helpful for you, then please read tutorials for docker and dockerizing spring boot applications.
You should use docker-compose. Best way to manage releases/versions and builds is to make own repository for dedicated docker images(nexus is an example).
In docker-compose you can describe all your infrastructure, create services, network, connecting services to communicate other services, so I think you should go this way to create nice developmnet and production build flow for your microservice application
For cassandra and other known services you can find prefered images on https://hub.docker.com.
In each microservice you should have Dockerfile, then in main directory of your solution you can create docker-compose.yml file with services definitions.
You can build your microservices in docker container too. Read more about "Java application build flow with docker" in google.
All about docker compose you can find here: https://docs.docker.com/compose/
All about docker swarm you can find here: https://docs.docker.com/engine/swarm/
Related
I have been working on a project where I have had several docker containers:
Three OSRM routing servers
Nominatim server
Container where the webpage code is with all the needed dependencies
So, now I want to prepare a version that a user could download and run. What is the best practice to do such a thing?
Firstly, I thought maybe to join everything into one container, but I have read that it is not recommended to have several processes in one place. Secondly, I thought about wrapping up everything into a VM, but that is not really a "program" that a user can launch. And my third idea was to maybe, write a script, that would download each container from Docker Hub separately and launch the webpage. But, I am not sure if that is best practice, or maybe there are some better ideas.
When you need to deploy a full project composed of several containers.
You may use a specialized tool.
A well known for mono-server usage is docker-compose:
Compose is a tool for defining and running multi-container Docker applications
https://docs.docker.com/compose/
You could provide to your users :
docker-compose file
your application docker images (ex: through docker hub).
Regarding clusters/cloud, we talk more about orchestrator like docker swarm, Kubernetes, nomad
Kubernetes's documentation is the following:
https://kubernetes.io/
Can I deploy both an asp.net Monolithic application and a Microservices application in the Same Docker Container? How to do it ?
Usually, this is not advisable, the better way is deploying two docker containers and possibly sharing a network (or other resources) between them
However, it's still possible to achieve by using one of two ways:
Make an entry point to be a script that starts all the required processes in one container.
Use tools like supervisord
A much more detailed explanation can be found here.
I'm new with docker, and have some doubts.
In a dev environment (not server), is better to use just one container, with apache, php and mysql for exemple, and use just a docker and a Dockerfile, or is better to use one container for each service, and use docker-compose to do it?
I have made this here with docker-compose, but I don't know if it is the best way, seems to me unnecessary complexity, but I'm newb.
I have the following situation, I work with magento, and is a common need to have a clear instalation for isolate modules and test, so I want create my magento 2 docker environment, where have just a clear magento and must have some easy way of put my module files inside, for test, and ons shutdown, the environment backs to clear magento 2 instalation, without my files, what is the best way to get this environemnt?
Thanks in advance.
I'd certainly recommend using a docker stack (defined in a docker-compose), and not trying to spin up a whole application stack inside a single container. You should have one service per container generally.
I believe what you are looking for in the second part of your question is a deployment orchestration tool. Docker does not replace deployment orchestration, but you can run shell scripts that do application setup in the Dockerfiles that build the containers you use in your stack.
As for access to files inside your containers, I'd look into docker volumes.
How should applications be scripted/automatically deployed when in LXD containers?
For example is best way to deploy applications in LXD containers to use a bash script (which deploys an application)? How to execute this bash script inside the container by executing a command on the host?
Are there any tools/methods of doing this in a similar way to Docker recipes?
In my case, I use Ansible to:
build the LXD containers (web, database, redis for example).
connect to the containers and deploy the services and code needed.
you can build your own images for example with the services and/or code already deployed and build specific containers from this images.
I was doing this from before LXD had Ansible support (Ansible 2.2) i prefer to use ssh instead of lxd connection, when i connect to the containers to deploy services/code. they comes with a profile where i had setup my ssh public key (to have direct ssh connection by keys ... no passwords)
Take a look at my open source project on bitbucket devops_lxd_containers It includes:
Scripts to build lxd image templates including Apache, tomcat, haproxy.
Scripts to demonstrate custom application image builds such as Apache hosting and key/value content and haproxy configured as a router.
Code to launch the containers and map ports so they are accessible to the larger network
Code to configure haproxy as layer 7 proxy to route http requests between boxes and containers based on uri prefix routing. Based on where it previously deployed and mapped ports.
At the higher level it accepts a data drive spec and will deploy an entire environment compose of many containers spread across many hosts and hook them all up to act as a cohesive whole via a layer 7 proxy.
Extensive documentation showing how I accomplished each major step using code snippets before automating.
Code to support zero-outage upgrades using the layer7 ability to gracefully bleed off old connections while accepting new connections at the new layer.
The entire system is built on the premise that image building is best done in layers. We build a updated Ubuntu image. From it we build a hardened Ubuntu image. From it we build a basic Apache image. From it we build an application specific image like our apacheKV sample. The goal is to never rebuild any more than once and to re-use the common functionality such as the basicJDK as the source for all JDK dependent images so we can avoid having duplicate code in any location. I have strived to keep Image or template creation completely separate from deployment and port mapping. The exception is that I could not complete creation of the layer 7 routing image until we knew everything about how other images would be mapped.
I've been using Hashicorp Packer with the ansible provisioner using ansible_connection = lxd
Some notes here for constructing a template
When iterating through local files on your host system you may need to be using ansible_connection = local (e.g for stat & friends)
Using local_action in ansible with the lxd connection is still
action inside the container when using stat (but not with include_vars & lookup function for files)
Using lots of debug messages in Ansible is helpful to know which local environment ansible is actually operating in.
I'm surprised no one here mentioned Canonicals own tool for managing LXD.
https://juju.is
it is super simple, well supported, and the only caveat is it requires you turn off ipv6 at the LXD/LXC side of things (in the network bridge)
snap install juju --classic
juju bootstrap localhost
from there you can learn about juju models, deploy machines or prebaked images like ubuntuOS
juju deploy ubuntu
I have a hunch that docker could greatly improve my webdev workflow - but I haven't quite managed to wrap my head around how to approach a project adding docker to the stack.
The basic software stack would look like this:
Software
Docker image(s) providing custom LAMP stack
Apache with several modules
MYSQL
PHP
Some CMS, e.g. Silverstripe
GIT
Workflow
I could imagine the workflow to look somewhat like the following:
Development
Write a Dockerfile that defines a LAMP-container meeting the requirements stated above
REQ: The machine should start apache/mysql right after booting
Build the docker image
Copy the files required to run the CMS into e.g. ~/dev/cmsdir
Put ~/dev/cmsdir/ under version control
Run the docker container, and somehow mount ~/dev/cmsdir to /var/www/ on the container
Populate the database
Do work in /dev/cmsdir/
Commit & shut down docker container
Deployment
Set up remote host (e.g. with ansible)
Push container image to remote host
Fetch cmsdir-project via git
Run the docker container, pull in the database and mount cmsdir into /var/www
Now, this looks all quite nice on paper, BUT I am not quite sure whether this would be the right approach at all.
Questions:
While developing locally, how would I get the database to persist between reboots of the container instance? Or would I need to run sql-dump every time before spinning down the container?
Should I have separate container instances for the db and the apache server? Or would it be sufficient to have a single container for above use case?
If using separate containers for database and server, how could I automate spinning them up and down at the same time?
How would I actually mount /dev/cmsdir/ into the containers /var/www/-directory? Should I utilize data-volumes for this?
Did I miss any pitfalls? Anything that could be simplified?
If you need database persistance indepent of your CMS container, you can use one container for MySQL and one container for your CMS. In such case, you can have your MySQL container still running and your can redeploy your CMS as often as you want independently.
For development - the another option is to map mysql data directories from your host/development machine using data volumes. This way you can manage data files for mysql (in docker) using git (on host) and "reload" initial state anytime you want (before starting mysql container).
Yes, I think you should have a separate container for db.
I am using just basic script:
#!/bin/bash
$JOB1 = (docker run ... /usr/sbin/mysqld)
$JOB2 = (docker run ... /usr/sbin/apache2)
echo MySql=$JOB1, Apache=$JOB2
Yes, you can use data-volumes -v switch. I would use this for development. You can use read-only mounting, so no changes will be made to this directory if you want (your app should store data somewhere else anyway).
docker run -v=/home/user/dev/cmsdir:/var/www/cmsdir:ro image /usr/sbin/apache2
Anyway, for final deployment, I would build and image using dockerfile with ADD /home/user/dev/cmsdir /var/www/cmsdir
I don't know :-)
You want to use docker-compose. Follow the tutorial here. Very simple. Seems to tick all your boxes.
https://docs.docker.com/compose/
I understand this post is over a year old at this time, but I have recently asked myself very similar questions and have several great answers to your questions.
You can setup a MySQL docker instance and have data persist on a stateless data container, aka the data container does not need to be actively running
Yes I would recommend having a separate instance for your web server and database. This is the power of Docker.
Check out this repo I have been building. Basically it is as simple as make build & make run and you can have a web server and database container running locally.
You use the -v argument when running the container for the first time, this will link a specific folder on the container to the host running the container.
I think your ideas are great and it is currently possible to achieve all that you are asking.
Here is a turn key solution achieving all of the needs you have listed.
I've put together an easy to use docker compose setup that should match your development workflow requirements.
https://github.com/ehyland/docker-silverstripe-dev
Main Features
Persistent DB
Your choice of HHVM + NGINX or Apache2 + PHP5
Debug and set breakpoints with xDebug
The README.md should be clear enough to get you started.