After migrating to Play-2.1 I stuck into problem that routes compiler stopped working for my routes file. It's been completely fine with Play-2.0.4, but now I'm getting the build error and can't find any workaround for it.
In my project I'm using cake pattern, so controller actions are visible not through <package>.<controller class>.<action>, but through <package>.<component registry>.<controller instance>.<action>. New Play routes compiler is using all action path components except for the last two to form package name that will be used in managed sources (as far as I can get code in https://github.com/playframework/Play20/blob/2.1.0/framework/src/routes-compiler/src/main/scala/play/router/RoutesCompiler.scala). In my case it leads to situation when <package>.<component registry> is chosen as package name, which results in error during build:
[error] server/target/scala-2.10/src_managed/main/com/grumpycats/mmmtg/componentsRegistry/routes.java:5: componentsRegistry is already defined as object componentsRegistry
[error] package com.grumpycats.mmmtg.componentsRegistry;
I made the sample project to demonstrate this problem: https://github.com/rmihael/play-2.1-routes-problem
Is it possible to workaround this problem somehow without dropping cake pattern for controllers? It's the pity that I can't proceed with Play 2.1 due to this problem.
Because of reputation I can not create a comment.
The convention is that classes and objects start with upper case. This convention is applied to pattern matching as well. Looking at a string there seems to be no difference between a package object and normal object (appart from the case). I am not sure how Play 2.1 handles things, that's why this is not an answer but a comment.
You could try the new # syntax in the router. That allows you to create an instance from the Global class. You would still specify <package>.<controller class>.<action>, but in the Global you get it from somewhere else (for example a component registry).
You can find a bit of extra information here under the 'Managed Controller classes instantiation': http://www.playframework.com/documentation/2.1.0/Highlights
This demo project shows it's usage: https://github.com/guillaumebort/play20-spring-demo
Related
This is not the first time I work with Inversify, but never had a problem like such. Currently what I have in my project is just a bunch of decorated (properly, constructor injections) services, therefore I assume it's failing on building the metadata.
I'm getting Error: #inject called with undefined this could mean that the class X has a circular dependency problem. You can use a LazyServiceIdentifer to overcome this limitation. whenever I start the application (bear in mind - I don't have a container yet).
Following the "circular dependency problem" part I built a dependency graph using dependency-graph package and it shows no circular dependencies in my project, it also managed to properly generate registration order.
I'm wondering if there's any way to avoid using LazyServiceIdentifier everywhere in the project?
Additionaly I'm trying to understand how is it even possible for this error to occur when using constructor injection (and having no circular dependencies of course)?
"The ambiguity, is in the box" - Monty Python.
Autofac is having a problem resolving an interface. See attached solution.
The Interface, IAmbiguous, is defined in project ACommon. It is implemented in project AInjectable. The AInjectable project does not / cannot reference ACommon. The AInjectable project defines IAmbiguous as an existing item brought in with a file link.
The UI project calls ACommon Inject and attempts to register the AInjectable assembly. IAmbiguous is not ambiguous initially but after a builder.RegisterAssemblyTypes command it becomes "ambiguous in the namespace." There is no error thrown when the container is built but the registration is not there.
Registration can be done "AsImplementedInterfaces" if Named and Keyed is not used. But then there is no way to Resolve the registration because the service IAmbiguous is "ambiguous in the namespace."
This question was double-posted as an issue on Autofac. It is not an Autofac problem. I will copy/paste the answer from the issue in here; for future readers, if you want to see the repro solution, go check out the full issue
What you're doing by including the same interface in two different assemblies isn't something you should be doing. Note that by doing that, your AInjectable class is not implementing the interface from the ACommon project. It's implementing a different but identically named interface.
This sort of thing is a problem - having the same type (interface, class, whatever) name in two different assemblies. We even had a problem (#782) where we had a System.SerializableAttribute in Autofac as a shim for .NET Core. You really just can't do that.
You'll also see the same thing if you try to make a static extension method class that has the same namespace and name as some other static extension method class. Ambiguous references.
Without doing Reflection.Emit style code generation, you won't be able to declare an interface in one assembly ("Assembly A") and implement that interface in a different assembly ("Assembly B") without having Assembly B reference Assembly A. That's just how .NET works. What you're seeing is a manifestation of that when you use Autofac, but it's not caused by Autofac. It's caused by you doing something you shouldn't be doing in .NET.
The fix is to define your interfaces in a separate assembly that everyone implementing the interfaces can reference. (Or you can try to dynamically generate code using Reflection.Emit or Roslyn or something, but that's waaaay harder.)
I've got a List of classes I want to send down to a Scala Template in Play! Framework 2.2.3
however I ran into some issues while trying to do so.
The class I want the list to contain is an arbitrary class type that comes from a package outside of my workspace, but not natively from Java. See the picture below.
Note: I do not have a project/Build.scala file.
The above image represents the first line in my scala template, I have tried to use #import as well (#import com.***.***.type._, com.***.***.type.Version, etc) but to no avail.
This is the error message given to me by Play! Framework.
Is there an issue with the namespacing? Everything works fine when using classes located in my workspace.
The Paths are correct, I've double checked that. For reasons I cannot disclose more code in this region, if more information is required please ask for it and I'll edit the post.
The problem is related to package named type. This word is reserved in Scala as language keyword. You need to escape it like this:
#import List[com.your.package.`type`.Version]
Today I cleared my .ivy cache and cleaned my project output targets. Since then I have been getting really strange behaviour when running tests with SBT or editing in the Scala IDE.
Given the following:
package com.abc.rest
import com.abc.utility.IdTLabel
I will get the following error:
object utility is not a member of package com.abc.rest.com.abc
Notice that com.abc is repeated twice, so it appears that the compiler uses the context of the current package when doing the import (maybe it's supposed to do this, but I never noticed it before).
Also, if I try to access classes in package com.abc from anywhere inside com.abc.rest (even using the full path) the compiler will complain that the type can not be found.
It appears that the errors only occur when I try to include files from parent packages. What I do find strange is that my code used to work. It only started happening after I cleaned up my project and my ivy cache, so maybe a later version of the compiler is more strict than the previous one.
I would love some ideas on what I can be doing wrong, or how I can go about troubleshooting this.
Update:
By first importing the parent classes and then defining the current package, the problem goes away:
import com.abc.utility.IdTLabel
import com.abs._
package com.abc.rest {
// Define classes belonging to com.abc.rest here
}
So this works, but I would still love to know why on earth the other way around worked, and then stopped working, and how on earth I can fix it. I had a good look, and could find no packages, objects or traits by the name of com anywhere inside the parent package.
Update relating to Worksheets:
Scala worksheets belonging to the same package share the same scope, which sounds obvious, but wasn't. Worksheets are not sand-boxed - they can see the project, and the project can see them. So all the 'test' object, traits, and classes you create inside the worksheet files, also becomes visible in the rest of the project.
I have so many worksheets that I did not even try to see where the problem came in. I simply moved them all to their own package, and like magic, the problem went away.
So, lesson learned for the day: If you create stuff inside worksheets, it's visible from outside the worksheet.
Anyway, this new found knowledge will come in handy, meaning anything 'interesting' can be build, monitored and tweaked inside the worksheet, while the rest of the project can actually use it. Quite cool actually.
It's still interesting to think how a sbt clean and cleaned up ivy cache managed to highlight the problem that was hidden before, but hey, that's another story....
(At the request of JacobusR, I'm making a proper answer out of my earlier comments).
This can happen if you have defined some class/trait/object inside package com.abc.rest.com. As soon as package com.abc.rest.com exists, and given that you are in package com.abc.rest, com would designate com.abc.rest.com as opposed to _root_.com. Fastest (but non-conclusive) way to check, without even scanning the source files, is to look for any .class files in the "com/abc/rest/com" sub-folder.
In particular you would get this behaviour if any of your files has duplicate package definitions (as in package com.abc.rest; package com.abc.rest; ...). If you have this duplicate package clause somewhere in the same file where you get the error, you wouldn't even see anything fishy with the .class files, as the failure at compiling the file would prevent the generation of .class files for any class definition inside the file.
The final bit of useful information is that as you found out the scala Worksheets are not sandboxed, and what you define in the worksheets affects your project's code (rather than only having the project's code affecting the worksheet). So a duplicate package clause in a worksheet could very well cause the error you got.
If package names conflict, there might be a custom error message for that. See if specifying the full path resolves the issue by starting from __root__. Ex. import __root__.com.foo.bar._
I'm trying to work through groovy's Implementing Local AST Transformations tutorial, but whenever I clean my project I get this error in each file that has the #WithLogging annotation in it:
Groovy:Could not find class for Transformation Processor AC.LoggingASTTransformation declared by AC.WithLogging
So you have a package named "AC" that contains both "WithLogging.groovy" and "LoggingASTTransformation.groovy" classes? Does it also contain any classes that implement the "WithLogging" interface?
If so, I'd suggest you move the class(es) that use your annotation to a location outside of the annotation defining package (the default will suffice, for diagnostic purposes) - Order of compilation matters with transformations. See this post on the groovy users mailing list for more on that.
Also try changing the annotation from #WithLogging to #AC.WithLogging.
As far as cleaning with Eclipse is concerned, I had a similar issue and found that I had to make a trivial modification after a clean to any file that contained my annotation. IE, add a space somewhere. Then save the file. This should rebuild everything properly.