When using Spring Couchbase connector I can easily get version for optimistic locking by having this in my class:
public class MyClass {
#Version
private String version;
.... rest of class omitted ....
}
I'm now trying to find a similar way to get and be able to modify the meta data for expiration. I'm unable to find how to do this.
Can someone please give an example? Thanks!
With spring data couchbase library (until the latest Version 3.0.8.RELEASE), document expiry can be defined by using #Document(expiry = 10) or #Document(expiryExpression = "${valid.document.expiry}") on the class. There is also an optional boolean attribute touchOnRead which needs to be added with #Document, which would reset the expiry timer whenever the document is directly read. Please note that currently the expiry of an existing document cannot be read/modified directly with this library. One way would be to access the below APIs exposed by Couchbase's own java SDK (com.couchbase.client.java)
getAndTouch - allows you to retrieve a document while modifying its expiration time
touch - allows you to modify a document’s expiration time without otherwise accessing the document
You can find the method signatures of the above two here : http://docs.couchbase.com/sdk-api/couchbase-java-client-2.2.4/com/couchbase/client/java/Bucket.html
The above two APIs can be accessed via the spring data couchbase library as follows
couchbaseTemplate.getCouchbaseBucket().touch(...)
couchbaseTemplate.getCouchbaseBucket().getAndTouch(...)
The getCouchbaseBucket() method of the spring library returns a reference to com.couchbase.client.java.Bucket using which the touch and getAndTouch methods can be used.
Related
I am writing a custom OpenApiConfigurator that adds some examples to my api dynamically.
When I add the examples using the value field of io.smallrye.openapi.api.models.examples.ExampleImpl, which is an object, the example is null in swagger-ui. It only works when I added the actual json.
To add the actual json I have to generate it from my response dto using Jackson. But how can I access the quarkus object mapper, for which I have some customisations using ObjectMapperCustomizer, if in the OpenApiConfigurator CDI is not available?
It's actually possible to access the CDI container statically with Arc.container().instance(ObjectMapper::class.java).get()
That solved it for me.
Dears, I'd like to auto-expire Redis keys when using org.springframework.integration.redis.store.RedisMessageStore class in Spring Integration. I see some methods related to "expiry callback" but I could not find any documentation or examples yet. Any advice will be much appreciated.
#Bean
public MessageStore redisMessageStore(LettuceConnectionFactory redisConnectionFactory) {
RedisMessageStore store = new RedisMessageStore(redisConnectionFactory, "TEST_");
return store;
}
Spring Boot: 2.6.3, spring integration and spring-boot-starter-data-redis.
The RedisMessageStore does not have any expiration features. And technically it must not. The point of this kind of store is too keep data until it is used. Look at it as persistent storage. The RedisMetadataStore is based on the RedisProperties object, so it also cannot use expiration feature for particular entry.
You probably talk about a MessageGroupStoreReaper, which really calls a MessageGroupStore.expireMessageGroups(long timeout), but that's already an artificial, cross-store implementation provided by the framework. The logic relies on the group.getTimestamp() and group.getLastModified(). So, still not that auto-expiration Redis feature.
The MessageGroupStoreReaper is a process needed to be run in your application: nothing Redis-specific.
See more info in docs: https://docs.spring.io/spring-integration/docs/current/reference/html/message-routing.html#reaper
I have develop a new Connector. This connector requires to be configured with two parameters, lets say:
default_trip_timeout_milis
default_trip_threshold
Challenge is, I want read ${myValue_a} and ${myValue_a} from an API, using an HTTP call, not from a file or inline values.
Since this is a connector, I need to make this API call somewhere before connectors are initialized.
FlowVars aren't an option, since they are initialized with the Flows, and this is happening before in the Mule app life Cycle.
My idea is to create an Spring Bean implementing Initialisable, so it will be called before Connectors are init, and here, using any java based libs (Spring RestTemplate?) , call API, get values, and store them somewhere (context? objectStore?) , so the connector can access them.
Make sense? Any other ideas?
Thanks!
mmm you could make a class that will create the properties in the startup and in this class obtain the API properties via http request. Example below:
public class PropertyInit implements InitializingBean,FactoryBean {
private Properties props = new Properties();
#Override
public Object getObject() throws Exception {
return props;
}
#Override
public Class getObjectType() {
return Properties.class;
}
}
Now you should be able to load this property class with:
<context:property-placeholder properties-ref="propertyInit"/>
Hope you like this idea. I used this approach in a previous project.
I want to give you first a strong warning on doing this. If you go down this path then you risk breaking your application in very strange ways because if any other components depend on this component you are having dynamic components on startup, you will break them, and you should think if there are other ways to achieve this behaviour instead of using properties.
That said the way to do this would be to use a proxy pattern, which is a proxy for the component you recreate whenever its properties are changed. So you will need to create a class which extends Circuit Breaker, which encapsulates and instance of Circuit Breaker which is recreated whenever its properties change. These properties must not be used outside of the proxy class as other components may read these properties at startup and then not refresh, you must keep this in mind that anything which might directly or indirectly access these properties cannot do so in their initialisation phase or your application will break.
It's worth taking a look at SpringCloudConfig which allows for you to have a properties server and then all your applications can hot-reload those properties at runtime when they change. Not sure if you can take that path in Mule if SpringCloud is supported yet but it's a nice thing to know exists.
My system is a dynamic telemetry system. We have hundreds of different spiders all sending telemetry back to the SpringBoot server, Everything is dynamic, driven by json files in Mongo, including the UI. We don't build the UI, as opposed to individual teams can configure their own UI for their needs, all by editing json docs.
We have the majority of the UI running and i began the middleware piece. We are using Spring Boot for the first time along with Spring Data Mongo with several MQ listeners for events. The problem is Spring Data. I started reading the docs on it and I realized the docs do not address using it without POJO's. I have this wonderfully dynamic model that changes per user per minute if the telemetry spiders dictate, I couldn't shackle this to a POJO if I tried. Is there a way to use Spring Data with a Map?
It seems from my experiments that the big issue is there is no way to tell the CRUD routines of the repository class what collection to query without a POJO.
Are my suspicions correct in that this won't work and am I better off ditching Spring Data and using the Mongo driver directly?
I don't think you can do it without a pojo when using spring-data. The least you could do is this
public interface NoPojoRepository extends MongoRepository<DummyPojo, String> {
}
and create a dummy pojo with just id and a Map.
#Data
public class DummyPojo {
#Id
private String id;
private Map<String, Object> value;
}
Since this value field is a map, you can store pretty much anything.
I have a Spring MVC application which returns Json and Xml based on what is requested per client call. I am using Jackson and Xstream to let Spring do the de-serialization of my java object into json or xml output.
My java object contains a bunch of attributes, at least 30. I would like to know if there is a way I can let Spring control which fields of my java object will be present in the json or xml based on a header or parameter attribute. So the client application will be able to identify itself and the backend will return only the fields necessary or "visible" for that specific client app. Of course I could go to the nasty approach of hard coding, but I would not like to do that as the number of client applications can increase or decrease and having a deployment anytime it happens with code changes is out of context.
Is there a way to instruct spring/jackson/xstream to control the output based on some providaded value?
I did a quick implementation and my current solution works like this: I have an xml with a list of client IDs (I use these ids to identify my client app) and for each ID I have a list of attributes that the client app needs from the java object. I created a interceptor and between the controller and the view, my interceptor gets the header information with the client ID, get the list of attributes and using the BeanWrapper (http://docs.spring.io/spring/docs/2.0.x/reference/validation.html) to create a new object with only the attributes required by the client with data, all the others remain null (I instruct Jackson and Xtream) to ignore null attributes. This approach works fine but I was wondering if there is another/better way to do this.
Thank you
TL