Requirement:
We need to store high-volume user session data in Spring boot for one of my projects using a session repository.
I have tried Redis as an option but unfortunately, it got failed in a clustered environment.
We want to store the non-persistence session in a clustered environment using a session repository.
Highly appreciated it if someone can share the peace of code or the git repo sample code. Please help.
Related
I have some properties in my microservice. They are changed a lot so I want to store them somewhere out of microservice so that I don't have to undeploy it again and again. One solution is to store them in database but it will be less efficient that way. Can you advise me a solution where I can store them?
Basically this microservice is used by a vast number of people. I want that file to be read ONCE when microservice is deployed (unless or until there is some change in the file) to minimize the calls.
You should use Spring Cloud Config which enables to use a centralized server which exposes a Git Repo which you can use to store environment specific configuration files (application.properties)
You should go with Centralized configuration, spring cloud supports config server, It is highly recommended for microservice architecture.
For reference: https://spring.io/guides/gs/centralized-configuration/
Basically, you have a centralized place to store all the configurations and don't need the redeploy the application every time you change the configs.
NOTE: in case you change the db properties then probably you need the restart the service
I am implementing a Spring Boot application which will be providing a multitenant environment. That is achieved in my case by using a database schema for each customer. Example see this project.
Now I am wondering how to implement tenant-specific configurations. I am using #ConfigurationProperties to bundle my property values, but these are getting instantiated once and not for each tenant.
What if I would like to use Spring Cloud Config with multiple tenant specific git repository as an configuration backend. Would it be possible when using a jdbc backend for Spring Cloud Config?
Is there any way with default Spring mechanisms or do I have to implement a database based configuration framework myself?
Edit: For example I have two tenants called Tenant1 and Tenant2. Both are running over the same application in the same context and are writing in the database schemes tenant_1 and tenant_2.
Identification of tenants is happening over keycloak (see Spring Keycloak multi tenant example). So I identify the tenantId from the jwt token and select the database connection like described here.
But now I would need the same mechanism for #Configuration beans. Since #Configuration beans are as far as I know Singletons, so there is always ONE configuration per application scope, and not ONE configuration per tenant.
So using Spring Cloud Config Tenant1 is using https://git-url/tenant1, Tenant2 is using Hashicorp Vault as backend and perhaps Tenant3 will be using a jdbc based configuration backend. And all of that in ONE (of course scalable) application.
In case your application uses tenant specific files (html templates etc), the following can be applied. As I have used the below approach for handling many tenants and works fine and easy to maintain.
I would suggest that you maintain a consistent configuration source (JDBC) for all of your tenant configurations. This helps you have a single source that is cacheable and scalable for your application. Also, you could have your tenants navigate to a configuration page to manage their settings and alter them to suit their needs at any point of time on the fly. (Example Settings: Records Per Page, Theme, Logo, Filters etc...)
Having the tenant configuration in files in git will be a difficult task when you wanted to auto-provision tenant's when they sign-up as it will involve couple of distributed services. Having them in a TenantSettings table with the tenantId as a column could help you get the data in no time and will be easy.
You can use Spring Cloud Config for your scenario and it is adoptable. It is easily configurable and provides out of the box features. For your specific scenario, you can have any number of microservices running yet all controlled by one Spring Cloud Config Server which is connected to one Git Repository. Your all microservices are asking configuration properties from Spring Cloud Config Server and it is directly fetching properties from Git Repository. That repository can have multiple property files. It can hold common properties for all the microservices or specific service based configuration properties. If you want to keep confidential properties more securely, that is also made possible via HashiCorp vault. I will leave an image below for you to get a better idea about this concept.
In the below image, you can see the Git Repository with common configuration property files and specific configuration property files for different services yet in same repository.
I will add another image for you to get a better idea how does this can be arranged with application profiles as well.
Finally I will add something additional to show the power of Spring Cloud Config and out of the box features it allows us to play with. You can automatically refresh configuration properties in running application as well. You can configure Spring Cloud Config to do that. I will add an architectural diagram to achieve that.
References for this answer is taken from Spring in Action, Fifth Edition
Craig Walls
I am new to spring boot, and recently started learning it, I have a question why do we create a repository in spring boot applications. Can anyone please explain to me logically?
Thanks in advance.
We build app to present data. These data may be static and small(In case we don't need Database).
But if want to store it some where and get it from somewhere we need services your service with use some data or consume some services.
So whenever to want to have a controller over the data and want to store it for future use you have to store to. To control the data you use repository.
I have a spring boot application where I am using some aws services.
The code in openly available in Git.
I don't want to commit AWS secret and access keys which are part of application.properties. I can't add to .gitignore as I want to commit other values of application.properties.
Many are committing to this repo. We are adding these aws keys in local and making sure its not added as part of any commit.
I want to make sure the aws keys in application.properties should not come to git at any cost. Which is the best way to manage these secret keys.?
You shouldn't be placing AWS API keys in application.properties at all. If the application is running on AWS it should be using the IAM role of the server it is running on. If it is not running on AWS it should probably be using environment variables.
Please review the documentation on this subject here.
Thanks to #Mark B. I would prefer using Java system properties as we can maintain them at application level. Env variables will be at system level which is not really needed and it may lead to conflicts.
while running an spring-boot jar with mvn, it can be done as below
mvn spring-boot:run -Dspring-boot.run.jvmArguments="-Daws.accessKeyId=XXXXXXXXXXX -Daws.secretKey=XXXXXXXXXXX"
if running for IDE like Eclipse or IntelliJ, it should be added as VM Options.
-Daws.accessKeyId=XXXXXXXXXXX -Daws.secretKey=XXXXXXXXXXXX
After this AWS client object can be built as usual.
As an example,
SNS client can be build by
AmazonSNS snsClient = AmazonSNSClient.builder().withRegion(Regions.US_EAST_1).build();
SES client can be built by
AmazonSimpleEmailService emailClient = AmazonSimpleEmailServiceClientBuilder.standard().withRegion(Regions.US_EAST_1).build();
I am learning Spring Boot using open-source projects and have stumbled upon their demo project — PetClinic. It has two possible databases configured: MySQL & HSQLDB, it uses the latter by default.
So I was able to launch the project look at it on localhost and can see that the DB (HSQLDB) is being populated but I was unable to set up a connection through the Intellij IDEA because the project does not specify the path that allows to see the contents of this in-memory DB.
Can anyone please tell me, what am I missing in the process of establishing the connection to HSQLDB here?
Thanks!
You can't connect to an in-memory instance of HSQLDB from another process.
The main drawback [of in-memory mode] is that it is not possible by default to connect to
the database from outside your application. As a result you cannot
check the contents of the database with external tools such as
Database Manager while your application is running.
If you want to do this, you need to run HSQL as a server. More details about how to run it in server mode can be found here.