I want following functionality in spring data rest.
If I post to a collection resource end point, server should check if the object exists. if it exists already it should perform the same functionality as it does with merge-patch on item resource. If object does not exist already it should create it.
Is this achievable in spring data rest. If so then how?
If it is possible in your use case, you might want to use PUT instead of POST, as PUT should work as you expected.
Solution with POST
You can achieve the desired behavior with Spring Data REST Event handlers.
Just create a Handler method which accepts your entity and annotate it with #HandleBeforeCreate. In this method, you can implement your behavior, i.e. check if the object exists and update it manually or just do nothing and let the Spring Data REST handle the entity creation.
#RepositoryEventHandler
public class EntityEventHandler {
#Autowired
private EntityService entityService;
#HandleBeforeCreate
public void handleEntityCreate(Entity e) {
if (entityService.exists(e)) {
entityService.update(e);
}
}
}
EDIT:
I just realized that you would also need to stop the create event after your update. You might try throwing a custom Exception and Handling it to return 200 and the updated entity.
Related
I am very new to Activiti BPMN. I am creating a flow diagram in activiti. I m looking for how username (who has completed the task) can be pass into shell task arguments. so that I can fetch and save in db that user who has completed that task.
Any Help would be highly appreciated.
Thanks in advance...
Here's something I prepared for Java developers based on I think a blog post I saw
edit: https://community.alfresco.com/thread/224336-result-variable-in-javadelegate
RESULT VARIABLE
Option (1) – use expression language (EL) in the XML
<serviceTask id="serviceTask"
activiti:expression="#{myService.toUpperCase(myVar)}"
activiti:resultVariable="myVar" />
Java
public class MyService {
public String toUpperCase(String val) {
return val.toUpperCase();
}
}
The returned String is assigned to activiti:resultVariable
HACKING THE DATA MODEL DIRECTLY
Option (2) – use the execution environment
Java
public class MyService implements JavaDelegate {
public void execute(DelegateExecution execution) throws Exception {
String myVar = (String) execution.getVariable("myVar");
execution.setVariable("myVar", myVar.toUpperCase());
}
}
By contrast here we are being passed an ‘execution’, and we are pulling values out of it and twiddling them and putting them back.
This is somewhat analogous to a Servlet taking values we are passed in the HTMLRequest and then based on them doing different things in the response. (A stronger analogy would be a servlet Filter)
So in your particular instance (depnding on how you are invoking the shell script) using the Expression Language (EL) might be simplest and easiest.
Of course the value you want to pass has to be one that the process knows about (otherwise how can it pass a value it doesn't have a variable for?)
Hope that helps. :D
Usually in BPM engines you have a way to hook out listener to these kind of events. In Activiti if you are embedding it inside your service you can add an extra EventListener and then record the taskCompleted events which will contain the current logged in user.
https://www.activiti.org/userguide/#eventDispatcher
Hope this helps.
I have used activiti:taskListener from activiti app you need to configure below properties
1. I changed properties in task listener.
2. I used java script variable for holding task.assignee value.
Code Snip:-
I have a dependency with parameters constructor. When I call the action more than 1x, it show this error:
Error activating IValidationPurchaseService
More than one matching bindings are available.
Activation path:
1) Request for IValidationPurchaseService
Suggestions:
1) Ensure that you have defined a binding for IValidationPurchaseService only once.
public ActionResult Detalhes(string regionUrl, string discountUrl, DetalhesModel detalhesModel)
{
var validationPurchaseDTO = new ValidationPurchaseDTO {...}
KernelFactory.Kernel.Bind<IValidationPurchaseService>().To<ValidationPurchaseService>()
.WithConstructorArgument("validationPurchaseDTO", validationPurchaseDTO)
.WithConstructorArgument("confirmPayment", true);
this.ValidationPurchaseService = KernelFactory.Kernel.Get<IValidationPurchaseService>();
...
}
I'm not sure what are you trying to achieve by the code you cited. The error is raised because you bind the same service more than once, so when you are trying to resolve it it can't choose one (identical) binding over another. This is not how DI Container is supposed to be operated. In your example you are not getting advantage of your DI at all. You can replace your code:
KernelFactory.Kernel.Bind<IValidationPurchaseService>().To<ValidationPurchaseService>()
.WithConstructorArgument("validationPurchaseDTO", validationPurchaseDTO)
.WithConstructorArgument("confirmPayment", true);
this.ValidationPurchaseService = KernelFactory.Kernel.Get<IValidationPurchaseService>();
With this:
this.ValidationPurchaseService = new ValidationPurchaseService(validationPurchaseDTO:validationPurchaseDTO, confirmPayment:true)
If you could explain what you are trying to achieve by using ninject in this scenario the community will be able to assist further.
Your KernelFactory probably returns the same kernel (singleton) on each successive call to the controller. Which is why you add a similar binding every time you hit the URL that activates this controller. So it probably works the first time and starts failing after the second time.
I'm relatively new to NHibernate and I've got a question about it.
I use this code snippet in my MVC project in Controller's method:
MyClass entity = new MyClass
{
Foo = "bar"
};
_myRepository.Save(entity);
....
entity.Foo = "bar2";
_myRepository.Save(entity);
The first time entity saved in database succesfully. But the second time not a single request doesnt go to database. My method save in repository just does:
public void Save(T entity)
{
_session.SaveOrUpdate(entity);
}
What should I do to be able to save and then update this entity during one request? If I add _session.Flush(); after saving entity to database it works, but I'm not sure, if it's the right thing to do.
Thanks
This is the expected behavior.
Changes are only saved on Flush
Flush may be called explicitly or implicitly (see 9.6. Flush)
When using an identity generator (not recommended), inserts are sent immediately, because that's the only way to return the ID.
you should be using transactions.
a couple of good sources: here and here.
also, summer of nHibernate is how I first started with nHibernate. it's a very good resource for learning the basics.
I am working on WCF Data service which imported stored procedure, as below.
[WebGet]
public List<GetMTSearchResultTest_Result> GettMTSearchResultTest()
{
MediaMarketResearch_PRODEntities ent = new MediaMarketResearch_PRODEntities();
return ent.GetMTSearchResultTest().ToList();
}
when i consuming this in my client application it says error as "The closed type MMRClient.MMRServiceReference.GetMTSearchResultTest_Result does not have a corresponding element settable property."
I am getting this error while bind to the grid view as below.
DataServiceContext context = new DataServiceContext(new Uri("http://localhost:4131/MMRDataService.svc/"));
IEnumerable<GetMTSearchResultTest_Result> empResult = context.Execute<GetMTSearchResultTest_Result>(new Uri("http://localhost:4131/MMRDataService.svc/GettMTSearchResultTest"));
GridView1.DataSource = empResult;
GridView1.DataBind();
Note: I imported this stored proc as complex type.
Please advice me on this.
Regards,
Jaydeep
I think this link may help you (see the selected answer).
Essentially, what the solution may be is to create a partial class for GetMTSearchResultTest_Result and decorate it with a DataServiceKey attribute, providing a non-nullable column that acts as a primary key (although I don't think it has to be unique).
So your partial class would look something like:
[DataServiceKey("YourKeyColumnName")]
public partial class GetMTSearchResultTest_Result {
}
If you're just doing reads, I don't think you'll need any implementation.
Hopefully this works. Let me know if there are issues/questions and I'll update accordingly.
You can always make a new service reference to a non data service. That is to a normal WCF service. You can simply have a [ContractOperation] returning a list of the troubled "complex types" and that's it.
This way you would have two services the original data service and a new normal WCF service. But this shouldn't be such an issue. You don't have to make the troubled "complex type" as a Entity.
We have a situation where we have multiple databases with identical schema, but different data in each. We're creating a single session factory to handle this.
The problem is that we don't know which database we'll connect to until runtime, when we can provide that. But on startup to get the factory build, we need to connect to a database with that schema. We currently do this by creating the schema in an known location and using that, but we'd like to remove that requirement.
I haven't been able to find a way to create the session factory without specifying a connection. We don't expect to be able to use the OpenSession method with no parameters, and that's ok.
Any ideas?
Thanks
Andy
Either implement your own IConnectionProvider or pass your own connection to ISessionFactory.OpenSession(IDbConnection) (but read the method's comments about connection tracking)
The solution we came up with was to create a class which manages this for us. The class can use some information in the method call to do some routing logic to figure out where the database is, and then call OpenSession passing the connection string.
You could also use the great NuGet package from brady gaster for this. I made my own implementation from his NHQS package and it works very well.
You can find it here:
http://www.bradygaster.com/Tags/nhqs
good luck!
Came across this and thought Id add my solution for future readers which is basically what Mauricio Scheffer has suggested which encapsulates the 'switching' of CS and provides single point of management (I like this better than having to pass into each session call, less to 'miss' and go wrong).
I obtain the connecitonstring during authentication of the client and set on the context then, using the following IConnectinProvider implementation, set that value for the CS whenever a session is opened:
/// <summary>
/// Provides ability to switch connection strings of an NHibernate Session Factory (use same factory for multiple, dynamically specified, database connections)
/// </summary>
public class DynamicDriverConnectionProvider : DriverConnectionProvider, IConnectionProvider
{
protected override string ConnectionString
{
get
{
var cxnObj = IsWebContext ?
HttpContext.Current.Items["RequestConnectionString"]:
System.Runtime.Remoting.Messaging.CallContext.GetData("RequestConnectionString");
if (cxnObj != null)
return cxnObj.ToString();
//catch on app startup when there is not request connection string yet set
return base.ConnectionString;
}
}
private static bool IsWebContext
{
get { return (HttpContext.Current != null); }
}
}
Then wire it in during NHConfig:
var configuration = Fluently.Configure()
.Database(MsSqlConfiguration.MsSql2005
.Provider<DynamicDriverConnectionProvider>() //Like so