I have a fragment bundle with a component that has an #Activate-annotated activate method. I can't find any definite information on whether this should or should not work.
On the one hand, it probably should work, in the sense that the Framework attaches a fragment to the host, then restarts the host. The component's activate method would then fire up, since it's now part of the host, which activates once more.
On the other hand, it probably should not work, since the Framework would not restart the host when attaching the fragment. In which case, the activate method never fires.
I tried tinkering with my bundle on my own, and it seems to not work, but I'm not sure if this is because of the latter case I mentioned above, or because of something else. I tried looking at the documentation, and there's no mention of how the Framework handles the lifecycle of a fragment and host during attachment, beyond the fact that the fragment gets resolved.
My question, then, is what does the OSGi Framework do with the host when attaching a newly-deployed fragment?
Declarative Services does not support the Service-Component header in fragment manifests. So while the classes of a component and the XML component description for a component can come from a fragment, any Service-Component header in a fragment's manifest is not processed.
See https://osgi.org/specification/osgi.cmpn/7.0.0/service.component.html#d0e38069.
Related
When I am creating a new session (or try to access from an other computer) in Vaadin Flow I get this error:
Can't move a node from one state tree to another
From this link, I read something about UI and getUIId().
However, I don't understand how I should change my application in order to fix the error.
As Denis mentioned in the forum post you linked, wrong scope sounds like the most likely culprit. In other words, you are trying to use the exact same component instance in two different UIs, when both UIs should have their own instance. It's not possible to use the same instance in two places at the same time.
You can find the documentation for Vaadin Spring scopes here: https://vaadin.com/docs/latest/flow/integrations/spring/scopes
One possible cause of errors such as that is that if you're storing a Component in a static variable. You shouldn't do that - a Component instance can only belong to a single UI. A single UI in turn (in practice) means a single browser tab.
I'm working on a Web service with Visual Studio, framework 4.7.1. One of its Web methods needs to call another Web service (provided by another company). It converts the parameters it receives (that are consistent with our main application's business logic) into values the other Web service can handle (according to it's own business logic). To do this, it relies heavily on data stored in the Web.config file.
I tested it directly (start the Web service and call the Web methods with automatically generated pages on a Web browser page) and everything worked fine.
Now, I need to build a test application (also in Visual Studio, framework 4.7.1) to call the same Web methods. On first testing it, I noticed that the Web service was trying to access the test application's config file instead of its own (as described in Can't read Web.config with ConfigurationManager.AppSettings ).
So I created an applicationSettings section in the Web.config and moved all the data from appSettings into it. It worked fine.
Now, however, I notice that the same thing happens with the custom sections. One of them looks like this:
<configSections>
<section name="jobTypeLists" type="AdelSoft_WS_FRA.JobTypesSection" />
</configSections>
<jobTypeLists>
<jobTypes>
<jobType codeCustomerType="A" codeJobType="JobForA" />
<jobType codeCustomerType="B" codeJobType="JobForB" />
</jobTypes>
</jobTypeLists>
I can see how such a structure could fit into its own .settings file, but I have another one that is much more complicated. (Like, the text nodes can have up to four ancestors.) To keep this short-ish, I'm not providing it now, but it can easily be arranged.
ConfigurationManager.GetSection("jobTypeLists") returns null when called from the test application. Same with WebConfigurationManager.GetSection("jobTypeLists").
I've also tried accessing the configuration file with ConfigurationManager.OpenExeConfiguration(AppDomain.CurrentDomain.SetupInformation.ConfigurationFile), but I can't seem to find my sections in the Configuration object it returns.
I'm not sure it means anything, but the Configuration object's FilePath property contains "C:\Folder\InnerFolder\WebServiceFolder\web.config.config". Why this second ".config"? I tried passing the same string to ConfigurationManager.OpenExeConfiguration(), without the ".config" extension: it returned null. (As it should, I feel.)
The Configuration object has 10 section groups and 22 sections, which I can't make heads or tails from. Likewise, I can list them.
Actually, there are two ways for a Visual Studio project to reference a Web service: as a regular reference (like you would any other project) or as a Web reference.
I was using the former, and therein lay my mistake.
To reference the Web service, I started it, copied the URL from the browser window that it opened, and pasted it into the "URL" text box in the "Add a Web reference" window from my test application. From there on, it worked fine.
(By the way, I have kept the regular reference as well, because I'm using some constants from the Web service to handle return values.)
I would like to be able to build functionality for my application in a plugin style system for a couple reasons:
New projects can choose which plugins are necessary and not have code for functionality that's not needed
Other developers can build plugins for the system without needing too much knowledge of the core workings.
I'm not really sure how to go about implementing this. I would like to have a plugins folder to host these separately but I guess my questions are:
How do plugins interact with the core system?
How does the folder structure work? Would each hold the standard MVC structure: controllers, services, models, views, etc?
I guess if anyone has a tutorial or some documentation relating to this technique that would be helpful. I've done a bit of searching but it's all a little too closely related to the actual code they're working with instead of the concept and I hadn't found anything specifically related to nodejs.
I suggest an approach similar to what I've done on the uptime project (https://github.com/fzaninotto/uptime/blob/master/app.js#L46):
trigger application events in critical parts of your application
add a 'plugins' section in the applicaition configuration
each plugin name must be a package name. The plugin packages should return either a callback, or an object with an init() function.
either way, inject to the plugins the objects they will need to run (configuration, connections, etc) when calling init(), or executing the callback.
plugin modules register listeners to the application events and modify it
Benefits:
lightweight
rely on npm for dependencies
don't reivent the wheel
Create a plugin prototype for the base
functionality, and let the user define its plugin in a module. In the
module the user would inherit an object from the prototype, extend its
functionality, and then export a constructor which returns the plugin
object.
The main system loads all plugins by require("pluginname") and for
each calls the constructor.
Do I even need this rule anymore?
I don't see any requests incoming for resource.axd files (as opposed to when I ran webform applications)
WebResource.axd is an HTTP Handler that is part of the .NET Framework
that does one thing and one thing only – it is tasked with getting an
embedded resource out of a DLL and returning its content. What DLL to
go to and what embedded resource to take are specified through the
querystring. For instance, a request to
www.yoursite.com/WebResource.axd?d=EqSMS…&t=63421… might return a
particular snippet of JavaScript embedded in a particular assembly.
Its still part of the framework and you can still retrieve embedded resources using the above handler. You dont want your route handler to handle such requests and that is why it is ignored. My guess is that you can get rid of it if you are completely sure that your app/libraries that you use dont use it.
I was hoping to make a Rails app usable both as an Engine and as a standalone Application.
Specifically, I have a nascent app which I'd like to plug in to a customer's site, but ideally, I'd like to just as easily use the app as a standalone system. However, if config/environments/*.rb exist in the enginified version of my app, I get an Uninitialized Constant error at the time the app that I'm having take a dependency on my engine starts up; Rails complains that the MyEngineModule::Application constant can't be found in development.rb, which I think is simply a load order issue, since this does NOT occur when I run the app standalone. If I delete development.rb, the original initializers that reference my MyEngineModule::Application complain, so then I tried to delete those, and all is well.
Great, except that the original app doesn't work, since its configuration is gone.
Is there some tweak I can make to the initialization load order (or load paths, in the Engine < Rails::Engine class definition) that would prevent the original configs and initializers from being loaded when in an engine context, and allow me to leave them in place for the app context?
The simpler answer is probably this, but I'm feeling stubborn, and would like to know what it would take to make my original goal possible:
extract the code for MyEngine into an engine, remove the config/environments/* files and config/initializers/* files, and make the client app depend on this.
Make a "new" minimalist app depend on MyEngine, and move the environment files and initializers to NewApp.
Assuming I feel some unnatural compulsion to keep my original application runnable as it was, if I want to prevent the "engine" from loading the "application" configuration, what's the best way to handle that? I presume this is only really a problem during development, because I can prevent the environments/*.rb files from being pulled into the gem itself, but I like being able to test locally while I'm developing the engine and its client app.
Continuing my tradition of answering my own esoteric questions, it seems like one passable alternative is to include a guard clause in the engine's environments/*.rb and the initializers that goes something like this:
if defined? CuteEngine::Application
CuteEngine::Application.configure do
config.whatever = something
end
end
This gets around the problem of having two Rails::Application objects at a relatively small cost. Not very happy about it, but I'll live.
Bumping this for new comers.
Rails 3.1 comes with mountable engines, which sounds like exactly what you are describing. The docs aren't great for converting existing code, but it looks like this will do what you want:
module CuteEngine
class Engine < ::Rails::Engine
isolate_namespace CuteEngine
end
end
In your other app's routes.rb file, you'll add:
mount CuteEngine::Engine, at: "/cuteness"
http://edgeguides.rubyonrails.org/engines.html#mounting-the-engine
http://railscasts.com/episodes/277-mountable-engines