I am using CefSharp. I have a RequestHandler which read data from a multiple databases. I would like to pass a context object which will contain a service instance which is bound to a specific database connection. I wonder what is the best way to do that using CefSharp. So far I was using global instance that is shared between the browser and the client code but I dont like that approach. Is there a way to set a "context" object per browser instance and use that context from the ResourceHandler?
Related
My Grails 4.0.10 app needs to call an external service. The call may take up to 3 minutes, so it has to be async'ed. After reading the doco I wrote a non-blocking service method to perform the call using a Promise without too much trouble.
The documentation describes how async outcome can be displayed.
In my case the outcome affects the database. I must create new domain objects, modify existing domain objects and persist the result in the onComplete closure. The doco is rather quiet on how to do this.
These are my assumptions about the onComplete closure. My question is: Are the assumptions valid? Is this the proper way to do it?
No injected stuff is available, neither services nor (for example) log -- things you normally expect in a service
Database logic must be enclosed first within Tenants.withId if multitenancy is used, and then within withTransaction
withTransaction is prefixed with a domain name. However, other domains may freely be manipulated and persisted in the same closure
Domain instances picked up before the async call may be attached to the current session like this instance.attach() and then modified and saved
If logging is needed, create a new log instance
I have problems deciding on how the OrmLiteConnectionFactory should be passed to the different classes. Should it be done by injecting the container into the constructors? It is a message based design if that matters.
Basically you'd just want to pass a "reference" to what connection you'd want your Service to be executed with.
ServiceStack's Multitenancy docs shows different approaches of specifying the DB connection to use per Request DTO message, including using a custom filter, or utilizing the built-in [ConnectionInfo] or [NamedConnection] attributes.
Or if you prefer you can resolve which DB connection you want to use with your Services logic by resolving it from a IDbConnectionFactory dependency.
I've searched endlessly and am unable to find a way to implement Memcached on Tapestry5 such that I instantiate only 1 "MemcachedClient" object for the entire application.
I have a page whose responses need to be cached.
I want to create only 1 instance of a "MemcachedClient" on this server (regardless of session) and query the cache using the same object instance.
I've tried #SessionState but this does not help, since my "user" is a load generator and hence each request results in a new object instance.
Any advice please?
Edit: The same goes for any other variable that I want to persist across visits, regardless of session. How can this be achieved?
You'll need to define a service in tapestry-ioc (services are singletons by default)
This will be done in your IOC module either with a builder method or via ServiceBinder.bind(...)
I was looking through an old project and wanted to see if anyone had a suggestion on how to hide certain methods from being called by various layers. This was a 3 tier project, webapplication -> web service -> database
In the application there is a User object for example. When a User was being updated, the webapplication would create a User object and pass it to the webservice. The webservice would use the DataAccessLayer to save the User object to the database. After looking at this I was wondering if instead I should have made a Save method in the User class. This way the service and simply call the Save on the User object which would trigger the db update.
However doing it this way would expose the Save to be called from the webapplication as well, correct? Since the webapplication also has access to the same User object.
Is there anyway around this, or is it better to avoid this altogether?
There is a separation of concerns by keepeing the User object as object that only holds data with no logic in it. you better keep it separated for the following reasons:
As you stated, it is a bad practice since the Save' functionality will be exposed to other places/classes where it is irrelevant for them (This is an important for programming generally).
Modifying the service layer - I guess you are using WCF web service as you can transfer a .NET object (c#/VB) to the service via SOAP. If you put the saving logic in the 'User' object, you can't replace it another webservice that receives a simple textual data structures like JSON or XML or simply doesn't support .NET objects.
Modifying the data storage layer - If you want, for example, to store the data inside a different place like other database such as MongoDB, RavenDB, Redis or what ever you want, you will have to reimplement each class that responsible for updating the data. This is also relevant for Unit Testing and Mocking, making them more complicated to interrogate.
We are mixing workflows, a workflow using receive activity's more at the end. But at the start we want to pass in some arguments (not using a receive activity!)
Our workflows are already being created and resumed using a dynamic endpoint with IWorkflowCreation and a class derived from WorkflowHostingEndpoint. In the OnGetCreationContext the creationgContext is filled with WorkflowArguments and the workflow runs. At a later part the receive activity's are creating a bookmark which can be resumed with a message. All seems nice.
But in a xamlx there are no WorkflowArguments, i understand why, except that i want them anyway. I though about an activity in which i can write some code to get the Arguments myself, but i do need some help here.
Or is there another way to pass along the WorkflowArguments into a xamls without using Messaging?
You can't pass arguments into a starting workflow service except through the SOAP message that starts it. But there is nothing preventing you from reading any properties in your workflow service. So it is perfectly fine to do read settings or something similar instead of passing them in at startup.
We have solved this exact situation by creating another WCF service which sits alongside our xamlx service on a slightly different url (e.g. /WorkflowMetadata) and this is where we implement a service method that returns a dictionary of string, type.
In the implementation of this service we simply read the xamlx and determine the arguments.
This is what we use to interrogate a target workflow in an activity designer when creating something like a launch-workflow activity.
Creating an activity will not work as that activity will need an instance in order to run. All you want is some metadata about the xamlx service. And if you are using a WorkflowCreationEndpoint to construct a creation context then you are probably only allowing a dictionary of string, object as the start parameters. Therefore standard metadata will not work. This left us with the only option being to provide another service beside the workflow which serves metadata.
Background here: http://blog.petegoo.com/index.php/2011/09/02/building-an-enterprise-workflow-system-with-wf4/