Spring Data JPA Disable #entity based on configuration - spring-data-jpa

We have a requirement to disable #entity based on configuration. is it possible?
We dont want to create a table so we should disable only few entity.

I can think of a couple of ways to handle this requirement, but the simplest one (assuming you're using Spring Boot) would probably be to group the required and optional entities in separate packages, and then setup the main configuration to include entities from the required package:
#SpringBootApplication
#EntityScan({"requiredpackageone", "requiredpackagetwo", ...})
public class MainApplication {
...
}
and then, enable entity scanning for the optional package, in an optional configuration:
#Configuration
#ConditionalOnProperty(...) // or #Profile, whichever works for you
#EntityScan("optionalpackage")
public class AdditionalEntityConfig {
// the class itself can be empty
}

Related

Consuming Properties at Spring Config Client

Is there way or reference materials on accessing properties exposed in Spring Cloud Config server at client? I know using #Value, I can get value for one element.
Is it possible to extend or write a framework which can act as layer to consume all such properties and works as bridge to connecting applications.
Using below Annotations and Configurations
#Configuration
#EnableConfigurationProperties
#ConfigurationProperties(prefix = "your.properties.")
#RestController
public class YourController{
private <dataType> <variableName>
/* Dont forget to generate setters and getters as this is bean */
}
Found solution #spencergibb link and other SO links

Ribbon: Unable to set default configuration using #RibbonClients(defaultConfiguration=...)

The #RibbonClients annotation allows us to customise the Ribbon configuration per client. This process is described in the documentation at http://projects.spring.io/spring-cloud/spring-cloud.html#_customizing_the_ribbon_client
This is all fine. I tried to use the same approach to override the default configuration that should be applied to all my clients. So I defined the following configuration class and made sure it is considered by the component scan:
#Configuration
#RibbonClients(defaultConfiguration = MyDefaultRibbonConfig.class)
public class MyRibbonAutoConfiguration {
}
Unfortunately, it turns out that MyDefaultRibbonConfig is not taken into account when building the ribbon client's application context. A quick look and trace at RibbonClientConfigurationRegistrar let me think my #RibbonClients(default=...) annotation is unconditionally overridden by the one provided by org.springframework.cloud.netflix.ribbon.eureka.RibbonEurekaAutoConfiguration.
However, it works if the #RibbonClients annotation is set on a inner class instead of a top-level class:
#Configuration
public class MyRibbonAutoConfiguration {
#Configuration
#RibbonClients(defaultConfiguration = MyDefaultRibbonConfig.class)
static class SubConfig {
}
}
This is a side-effect the strategy followed by RibbonClientConfigurationRegistrar to give a name to the discovered configuration beans:
registerClientConfiguration(registry,
"default." + metadata.getEnclosingClassName(),
attrs.get("defaultConfiguration"));
The configuration for annotations declared on a top-level class are then registered with a bean name set to default.null.defaultConfiguration - so the next one overrides the previous (not sure the order is predictable though).
This behaviour looks strange to me. Did I miss something? Should I proceed differently?
This was an issue in SpringCloud-Netflix 1.0.1. See https://github.com/spring-cloud/spring-cloud-netflix/issues/374 for more information.

spring data solr showcase

I am trying to understand the spring data solr showcase project.
https://github.com/christophstrobl/spring-data-solr-showcase
After spending quite a bit of time, I could not find how the productRepository is implemented and injected in https://github.com/christophstrobl/spring-data-solr-showcase/blob/master/src/main/java/org/springframework/data/solr/showcase/product/ProductServiceImpl.java
#Service class ProductServiceImpl implements ProductService {
private static final Pattern IGNORED_CHARS_PATTERN = Pattern.compile("\\p{Punct}");
private ProductRepository productRepository;
#Autowired
public void setProductRepository(ProductRepository productRepository) {
this.productRepository = productRepository;
}
The ProductRepository is defined as interface (https://github.com/christophstrobl/spring-data-solr-showcase/blob/master/src/main/java/org/springframework/data/solr/showcase/product/ProductRepository.java) and I did not find any code implementing this interface
interface ProductRepository extends SolrCrudRepository<Product, String> {
#Highlight(prefix = "<b>", postfix = "</b>")
#Query(fields = { SearchableProductDefinition.ID_FIELD_NAME,
SearchableProductDefinition.NAME_FIELD_NAME,
SearchableProductDefinition.PRICE_FIELD_NAME,
SearchableProductDefinition.FEATURES_FIELD_NAME,
SearchableProductDefinition.AVAILABLE_FIELD_NAME },
defaultOperator = Operator.AND)
HighlightPage<Product> findByNameIn(Collection<String> names, Pageable page);
#Facet(fields = { SearchableProductDefinition.NAME_FIELD_NAME })
FacetPage<Product> findByNameStartsWith(Collection<String> nameFragments, Pageable pagebale);
}
Below is how the spring context is configured:
https://github.com/christophstrobl/spring-data-solr-showcase/blob/master/src/main/java/org/springframework/data/solr/showcase/Application.java
If anyone could point me to the direction where this interface is implemented and injected, that would be great.
The showcase makes use of Spring Data repository abstractions using query derivation from method name. So the infrastructure provided by Spring Data and the Solr module take care of creating the required implementations for you. Please have a look at the Reference Documentation for a more detailed explanation.
The showcase itself is built in a way that allows you to step through several stages of development by having a look at the diffs transitioning from one step to the other. So having a look at Step 2 shows how to make use of Custom Repository Implementation, while Step 4 demonstractes how to enable Highlighting using #Highlight.
The goal of Spring Data is to reduce the amount of boilerplate coding (means to reduce repetition of code).
For the basic methods like save,find the implementation will provide by spring and spring will create beans(Objetcs) for these interfaces. To tell the spring that these are my repositories inside this package, we are writing #EnableJpaRepositories(basePackeges="com.spring.repositories") or <jpa:repositories base-package="com.acme.repositories"/> for JPA repositories
Foring solr repositores we have to write #EnableSolrRepositories(basePackages="com.spring.repositories" or <solr:repositories base-package="com.acme.repositories" /> Spring will create objetcs for these interfaces, we can inject these interface objetcs using #Autowire annotation.
Example:
#Service
Pulic class SomeService{
#Autowire
private SampleRepository;
/* #postConstruct annotation is used to execute method just after creating bean
and injecting all dependencies by spring*/
#PostConstruct
public void postConstruct(){
System.out.println("SampleRepository implementation class name"+ SampleRepository.getClass());
}
}
The above example is to see the implementation class of SampleRepository interface (This class is not user defined, it is class given by spring).
For reference documentation link http://docs.spring.io/spring-data/solr/docs/2.0.2.RELEASE/reference/html/. Try to read this simple documentation you can get more knowlede on spring-data.

SetExecutionStrategy to SqlAzureExecutionStrategy with DbMigrationsConfiguration?

I saw a post today about implementing SqlAzureExecutionStrategy:
http://romiller.com/tag/sqlazureexecutionstrategy/
However, all examples I can find of this use a Configuration that inherits from DbConfiguration. My project is using EF6 Code First Migrations, and the Configuration it created inherits from DbMigrationsConfiguration. This class doesn't contain a definition for SetExecutionStrategy, and I can find no examples that actually combine SqlAzureExecutionStrategy (or any SetExecutionStrategy) with DbMigrationsConfiguration.
Can this be done?
If anyone else comes across this question, this is what we figured out:
Create a custom class that inherits from DbConfiguration (which has SetExecutionStrategy):
public class DataContextConfiguration : DbConfiguration
{
public DataContextConfiguration()
{
SetExecutionStrategy("System.Data.SqlClient", () => new SqlAzureExecutionStrategy());
}
}
Then add this attribute to your DataContext, specifying that it is to use your custom class:
[DbConfigurationType(typeof(DataContextConfiguration))]
public class DataContext : DbContext, IDataContext
{
...
}
After more investigation, now I think the correct answer is that:
DbMigrationsConfiguration is completely separate and only configures the migration settings. That's why it doesn't inherit from or have the same options as DbConfiguration.
It is not loaded, and is irrelevant, for actual operation.
So you can (and should) declare a separate class based on DbConfiguration to configure the runtime behaviour.
I added some tracing and I saw that the first time you use a DatabaseContext in an application, it runs up the migration, and the migration configuration.
But, the first time the DatabaseContext is actually used (e.g. to load some data from the database) it will load your DbConfiguration class as well.
So I don't think there is any problem at all.

How can I make all entities multitenant with Eclipselink 2.3

I'm working in a Java project where I need to make automatically an application (ear file) multitenant. A minimum configuration (view here http://wiki.eclipse.org/EclipseLink/Development/Indigo/Multi-Tenancy) to enable multitenancy in a given entity is :
#Entity
#Table(name="EMP")
#Multitenant
public Employee() {
...
}
My goal is to add dynamically the #Multitenant annotation to all entities and my question is: is there a solution other that editing the bytecode to add this annotation?
Thanks in advance.
You could use an orm.xml if you don't want to change the code.
You could also use a SessionCustomizer to configure a MultitenantPolicy on each ClassDescriptor.