WordPress's database blue-green deployment on Azure - mysql

We have a WordPress's application on the Azure's WebApp.
We have two environments there - DEV and Prod. Prod have a Staging swap-slot.
DEV and PROD, obviously, use different MySQL database (we using MySQL In App now, but the same question related to ClearDB/MySQL setup).
So, question is - how to do Blue-green deployment? What to do with databases?
We have Travis configured to deploy code to different environments. But - Prod's database will be updated during its usage be visitors, and DEV will be updated with developers (and, sure - will not have visitor's changes from Prod).
Are there any solutions/practises to realize that?
P.S. And there is one more issue. "MySQL In App (preview)" does not allow to have separated database for WebApp and its Stage (swap-slot). This creates an additional headache for us.

Related

Elastic Beanstalk - Environment properties not saving

I have a load balanced EB environment, running a PHP application on an Apache server.
We have successfully deployed the identical software to a test environment in this AWS account, as a pre-production test. This went as expected, and updated the sortware with each CLI deployment.
I cloned this environment in order to deploy the production instance. Generally, deploying the application via EB CLI results in a healthy instance. I say generally because occasionally this shows as degraded - to fix this, I select the latest application version and deploy it to the instance via the admin interface. This feels like a workaround because the console already shows the correct version as the one deployed.
The problem I am having now is in changing the environment variables, to point to the production database. When I change this via the configuration>software section, no changes are stored. When I hit 'apply' the environment starts to transition. When this is complete, the instance health has degraded and the changes made to the configuration are not persisted.
I don't really see a pattern here, and it's behaving in a way that differs from the way the test instance did - I had no problems there.
Any suggestions on how to get past this?

How to properly use databases in development?

I'm struggling with finding out how to properly test stuff on my local PC and then transfer that over to production.
So here is my situation:
I got a project in NodeJS/typescript, and I'm using Prisma in it for managing my database. On my server I just run a MySQL database, and for testing on my PC I always just used SQLite.
But now that I want to use Prisma Migrate (because it's highly recommended to do so in production) I can't because I use different databases on my PC vs on my Server. Now here comes my question, what is the correct way to test with a database during development?
Should I just connect to my server and make a test database there? Use VS Code's SSH coding function to code directly on the server and connect to the database? Install MySQL on my PC? Like, what's the correct way to do it?
Always use the same brand and same version database in development and testing that you will eventually deploy to. There are compatibility differences between brands, i.e. an SQL query that works on SQLite does not necessarily work the same on MySQL, and vice-versa. Even data types and schema definitions aren't all the same between different SQL products.
If you use different SQL databases in development and production, you will waste a bunch of time and increase your gray hair debugging problems in production, as you insist, "it works on my machine."
This is avoidable!
When I develop on my local computer, I usually have an instance of MySQL Server running in a Docker container on my laptop.
I assume any test data on my laptop is temporary. I can easily recreate schema and data at any time, using scripts that are checked into my source control repo, so I don't worry about losing any data. In fact, I feel no hesitation to drop it and recreate it several times a week.
So if I need to upgrade the local database version to match an upgrade on production, I just delete the Docker container and its data, pull the new Docker image version, initialize a new data dir, and reload my test data again.
Every step is scripted, even the Docker pull.
The caveat to my practice is that you can't necessarily duplicate the software if you use cloud databases, for example Amazon Aurora. There's no way to run an Aurora-compatible instance on your laptop (and don't believe the salespeople that Aurora is fully compatible with MySQL; it's not). So you could run a small Aurora instance in a development VPC and connect to that from your app development environment. At least if your internet connection is reliable enough.
By the way, a similar rule applies to all the other technology you use in development. The version of Node.js, Prisma, other NPM dependencies, http and cache servers, etc. Even the operating system might be the source of compatibility issues, but you may have to develop in a Virtual Machine to match the OS to production exactly.
At one past job, I did help the developer team create what we called the "golden image" which was a pre-configured VM with all our software dependencies installed, and we used this golden image for both the developer sandbox VM, and also an AMI from which we launched the production Amazon EC2 instances. So all the developers were guaranteed to have a test environment that matched production exactly. After that, if they had code problems, they could fix it in development and have a much higher confidence it would work after deploying to production.

Docker image and DB Server integration

We are using Docker Images for Spring Boot Rest Services. the current setup is working fine in Production. We want to use the similar setup in Development Environment. The spring boot image needs to connect to the database. At this point we have couple of options:
Have a centralized database server and have all the docker images from each development machine to connect to it.
Create a separate database image and have the developers run it along with the Spring boot image in the same Dev Machine.
Option #1 is easier to implement but if there is a change in the database, it may impact the whole development community in the organization, Option #2 mitigates that risk but it creates the problem of DataSync i.e when someone starts both these images, how to make sure it has all the required data.
I am wondering if there is any other option I need to consider or given these two options, which makes sense?
I went with option #2, it helps to provide isolated work environment.

Java EE application deployment on Amazon EC2

We have a Java EE application (EAR file deployed on JBoss, MySQL, MongoDB) which we would like to deploy on an Amazon EC2 instance. I have several questions regarding deployment best practices.
What is the most commonly used Linux AMI which we can rely on for a robust deployment (There are so many Linux variants, and I am not sure which AMI is commonly used, is it Fedora, CentOS, Red Hat, SUSE ...)
How do we handle production upgrades (EAR file modifications or schema upgrades). Are there any tools which are available to handle this installation or rollback of these changes.
What kind of data backup capability is available for the database?
Should I rely on Amazon RDS for MySQL support?
How should I handle support for MongoDB?
This is the first time, I am hosting an web-app and would appreciate some inputs on how to manage the production instance.
I agree with Mark Robinson's answer: Use whichever Unix variant you're most comfortable with. It may pay to pick one with decent cloud support. For my site I use Ubuntu.
I have a common image which is the base of every version deploy I do. I have www.mysite.com pointing to an Elastic IP so I can decide which instance it goes to. The common image has all the software I need installed (Postgres/Postgis/Tomcat/etc) but the database and web server data folders and symlinked to Elastic Block Store (EBS) instances.
When it comes time to do a deploy I start a new instance up, freeze and snapshot the EBS volumes on production and make new volumes. I point my new instance at the new volumes and then install whatever I need to onto that. Once I've smoke tested everything successfully I can switch the Elastic IP to point to the new instance and everything keeps on going.
I'll note that I currently have the advantage where only I can modify the database; no users can. This will become a problem shortly.
If you use the XFS filesystem on top of the EBS volume then you can tell XFS to freeze the file system (so no updates happen) then call the EC2 api to snapshot the volume then unfreeze the file system. The result is that the snapshot is taken quickly and sent to S3. I have a nightly script which does this.
If RDS looks like it will suit your needs then use it. Amazon is building lots of solid tools quickly and this will ease your scalability issues if you have any.
I'm sorry, I have no idea.
Good question!
1) I would recommend going with whatever Linux variant you are most comfortable with. If you have someone who is really keen on CentOS, go with that. Once you have selected your AMI, take it and customize it by configuring how you want it. Then save that AMI as you base-layout. It will make rolling out new machines much easier and save your bacon if EC2 goes down.
2) Upgrades with EC2 can be tres cool. Instead of upgrading a live system, take your pre-configured AMI, update that and save that AMI as myAMI-1.1 (or whatever). That way, you can flip over to the new system almost instantly AND roll back to a previous version in case something breaks. You can also back-up DB instances to S3. It's cheap at about $0.10/GB/Month.
3) It depends where you are storing your DB. If you are storing it on your EC2 instance you are in trouble. The EC2 instances have no persistence storage. So if your machine crashes, you lose everything. I'm not familiar with Amazon DB system but you should also look into Elastic Block Store. It's basically an actual hard-drive you can write to. When you want to upgrade your schema, do a full DB dump to S3 and then do an upgrade of your actual schema. If something goes wrong, you can pull the previous version out of S3.
4) & 5) I have never used those so I can't help you.
What is the most commonly used Linux AMI which we can rely on for a robust deployment (There are so many Linux variants, and I am not sure which AMI is commonly used, is it Fedora, CentOS, Red Hat, SUSE ...)
How do we handle production upgrades (EAR file modifications or schema upgrades). Are there any tools which are available to handle this installation or rollback of these changes.
What kind of data backup capability is available for the database?
Should I rely on Amazon RDS for MySQL support?
How should I handle support for MongoDB?
Any Linux AMI will do the job, what you need is a JRE only. (assuming development work not required). If you need to monitor the JVM behavior then get JConsole installed.
Easiest and painless way is to SSH into the local home directory, transfer the updated class file/EAR file (depends the number of changes applied) and copy and replace into the Tomcat deployment directory, restart apache. (make sure you tested locally before upload to production).
Depends on which database you are using, if you are using MySQL then just do scheduled backup that writes to your home directory so that from time to time you could SSH in and download a copy for backup purpose.
I would not consider reply on Amazon RDS for MySQL support due to 2 reasons: MySQL is small enough and manageable, and also I would want to have total complete control of the database and why pay for more when you can do it yourself FOC?
The usage of MongoDB should be align with the purpose of your application and benefits you gain from that. I would recommend you use MongoDB for static data retrieval like state, country, area etc... where MySQL to be use for transaction data only.
If you can live with deploying your Java EE application on TomEE instead of JBoss, Boxfuse does what you want.
For you Java EE application you literally only have to execute (TomEE uses war files instead of ear files):
boxfuse run my-tomee-app-1.0.war -env=prod
This will
Create AMI containing TomEE and your application ready to boot
Create an Elastic IP or ELB
Create a security group with the correct ports defined
Create an auto-scaling group
Launch your instance(s)
Any subsequent update will be done as a zero downtime blue/green deployment.
More info: https://boxfuse.com/blog/javaee-aws

How to manage a test database in SQL Server

I am currently working on an application that uses a SQL Server 2008 database that sits internally on a LAN. I am having two problems related to managing the database:
Currently, I have 2 databases in SQL server, one for test and one for production, and I copy tables and views etc... between these two databases when deploying changes. I'm assuming there is a better way to manage pushing changes from the test database to the production database, can anyone point me in the right direction here?
I do a good portion of my work remotely, so I have installed SQL Server 2008 Express to my laptop and run a 3rd copy of the database locally. Is this the best option for doing remote work? The solution I've been looking for in this situation is to expose my test database to the web with a limited user that I could use for when I am developing remotely. Is this feasible/recommended?
I have found that using my own, local copy of SQL Server Developer Edition on my notebook is the best way to do dev work overall; then a separate test and production database on servers. I like keeping my local dev server so that I am never at the mercy of connections to do dev work.
As a principle, I don't expose SQL servers publicly ever, so working through a VPN is the only way I can access my typical test/production servers. If my dev server was there, too; I would often be unable to do dev work when, for example, I am at a location where VPN pass-through is not permitted.
As for updating the production/test databases; I always generate change scripts when ever I change the dev server, and then keep them organized so they can be applied to the test and then later production servers. You can generate those scripts via SQL Server Management Studio or Visual Studio.
Probably the cleanest most repeable way is to use a real build process for your database code and objects. First put all your database code and objects in source control. Then use DBGHOST to create upgrade scripts to get your production database upgraded. As part of this you can create output that will create a empty dev database that matches any given release easily when using DBGhost. We have been using for about 3 years now and wouldn't do it any otherway. Check out there site for a full walk through. Well well worth the money. Did I say it's well worth the money?
http://www.innovartis.co.uk/