how can I have a valid jsonp file that contains two different callback
test.jsonp
a_callback({x:1});
b_callback({x:1});
when I put two callback in one file I get
Uncaught ReferenceError
error
If you are getting a reference error, then you are trying to reference something that doesn't exist. The error message should tell you what that is.
There is nothing stopping you putting two function calls in a dynamically loaded JavaScript file (which is, essentially, what JSONP is).
Related
we have a Zend_Soap_Server and a corresponding client, based on the same WSDL and the method "sendsth" is handled correctly if called from the PHP client.
Now I need to call it from perl so I create a client with SOAP::Lite, again using the same WSDL. When I call the method from the client I get an error in the server:
PHP Fatal error: Procedure 'sendsth' not present in /usr/local/zend/share/ZendFramework/library/Zend/Soap/Server.php
Do you have an idea what could be wrong or how to debug that?
Interesting aspect:
even if I wrap the call to $server->handle() in a try/catch block the program crashes exactly there
In GWT application I have RPC interface. Some methods works fine (i.e. RemoeServiceServlet configured fine), but when I try to invoke another method, it always fails with onFailure() method. Ajax call also don't occur (I can see it using FireBug, also on server side method invocation don't occur), but another methods of this service performs Ajax calls as well.
When I try to log error using e.getMessage() I get "undefined" message. Also I tried to wrap RPC calling code using try-catch - no error message.
Can this issue be related with GWT-RPC Serialization?
EDIT: Opera Dragonfly showed error on following method inside generated JavaScript (compiled with PRETTY mode):
function $check(this$static, typeSignature){
if (isNull($get_3(this$static.methodMapNative, typeSignature))) {
Unhandled Object: undefined
throw new SerializationException_1(typeSignature);
}
}
with error message
Unhandled Object: undefined
I would guess that you have a Serialization issue, remember that Java Serialization is not the same as GWT Serialization.
There is often no meaningful error message on Serialization errors when using RPC.
must have 0-ary constructor
final fields are inherently transient (ie. do NOT use final fields in classes intended to be serialized)
collections (ex List and Set) must be annotated with #gwt.typeArgs. #gwt.typeArgs is a JavaDoc annotation, thus it must be wrapped in a JavaDoc comment
ex.: /** #gwt.typeArgs */
For more details see:
GWT Serialization
Another thing to try:
When running GWT from the eclipse-plugin, a folder in the eclipse project is created (I belive its called gwt-unitCache). Sometimes my own GWT projects get ill and output strange exceptions, I can solve this by deleting the folder and run the project again.
I have a simple form that passes data to backbone, which in turn, submits requests to a tastypie REST API. The validation is done server side.
When a specific field has an error, how would I go about returning that error and handling it in backbone so it can be displayed alongside the field? Keeping in mind that backbone is expecting a model in return and not a bunch of errors (returning an array of errors with the associated fields sounds fine but I have a special backbone parse method that gets the objects out of the tastypie response - sending back random stuff will probably make it choke...?).
Confused as to why this isn't a common task to do.
Tastypie should be returning your validation errors with an http error-level code 4xx, not a success-level code 2xx.
Because of this, Backbone should be triggering the error callback, not the success callback.
Because the error callback is being triggered, Backbone doesn't invoke parse or anything else that happens on success.
So, you need to create a handler for tastypie errors, and pass that error handler function as the error callback.
From there, you can manually parse the body of the response and deal with the errors however you see fit for your app.
Many of the Caché API methods return a %Status object which indicates if this is an error. The thing is, when it's an unknown error I don't know how to handle (like a network failure) what I really want to do is "throw" the error so my code stops what it's doing and the error gets caught by some higher level error handler (and/or the built-in %ETN error log).
I could use ztrap like:
s status = someObject.someMethod()
ztrap:$$$ISERR(status)
But that doesn't report much detail (unlike, say, .NET where I can throw an exception all the way to to the top of the stack) and I'm wondering if there are any better ways to do this.
Take a look at the Class Reference for %Exception.StatusException. You can create an exception from your status and throw it to whatever error trap is active at the time (so the flow of control would be the same as your ZTRAP example), like this
set sc = someobj.MethodReturningStatus()
if $$$ISERR(sc) {
set exception = ##class(%Exception.StatusException).CreateFromStatus(sc)
throw exception
}
However, in order to recover the exception information inside the error trap code that catches this exception, the error trap must have been established with try/catch. The older error handlers, $ztrap and $etrap, do not provide you with the exception object and you will only see that you have a <NOCATCH> error as the $ZERROR value. Even in that case, the flow of control will work as you want it to, but without try/catch, you would be no better off than you are with ZTRAP
These are two different error mechanisms and can't be combined in this way. ztrap and %ETN are for Cache level errors (the angle bracket errors like <UNDEFINED>). %Status objects are for application level errors (including errors that occurred through the use of the Cache Class Library) and you can choose how you want to handle them yourself. It's not really meaningful to handle a bad %Status through the Cache error mechanism because no Cache error has occurred.
Generally what most people do is something akin to:
d:$$$ISERR(status) $$$SomeMacroRelevantToMyAppThatWillHandleThisStatus(status)
It is possible to create your own domain with your own whole host of %Status codes with attendant %msg values for your application. Your app might have tried to connect to an FTP server and had a bad password, but that doesn't throw a <DISCONNECT> and there is no reason to investigate the stack, just an application level error that needs to be handled, possibly by asking the user to enter a new password.
It might seem odd that there are these two parallel error mechanisms, but they are describing two different types of errors. Think of one of them being "platform" level errors, and the other as "application level errors"
Edit: One thing I forgot, try DecomposeStatus^%apiOBJ(status) or ##class(%Status).LogicalToOdbc(status) to convert the status object to a human readable string. Also, if you're doing command line debugging or just want to print the readable form to the principal device, you can use $system.OBJ.DisplayError(status).
I am not able to understand the places where an error handling or where an exception handling should be used. I assume this, if it is an existing framework class there are delegate methods which will facilitate the programmer to send an error object reference and handle the error after that. Exception handling is for cases where an operation of a programmer using some framework classes throws an error and i cannot get an fix on the error object's reference.
Is this assumption valid ? or how should i understand them ?
You should use exceptions for errors that would never appear if the programmer would have checked the parameters to the method that throws the exception. E.g. divide by 0 or the well known "out of bounds"-exception you get from NSArrays.
NSErrors are for errors that the programmer could do nothing about. E.g. parsing a plist file. It would be a waste of resources if the program would check if the file is a valid plist before it tries to read its content. For the validity check the program must parse the whole file. And parsing a file to report that it is valid so you can parse it again would be a total waste. So the method returns a NSError (or just nil, which tells you that something went wrong) if the file can't be parsed.
The parsing for validity is the "programmer should have checked the parameters" part. It's not applicable for this type of errors, so you don't throw a exception.
In theory you could replace the out of bounds exception with a return nil. But this would lead to very bad programming.
Apple says:
Important: In many environments, use of exceptions is fairly commonplace. For example, you might throw an exception to signal that a routine could not execute normally—such as when a file is missing or data could not be parsed correctly. Exceptions are resource-intensive in Objective-C. You should not use exceptions for general flow-control, or simply to signify errors. Instead you should use the return value of a method or function to indicate that an error has occurred, and provide information about the problem in an error object.
I think you are absolutely right with your assumption for Errors and for it framework provide a set of methods (UIWebView error handling ), But your assumption for Exception partially right because the exception only occurred if we do something wrong which is not allowed by the framework and can be fixed. (for example accessing a member from an array beyond its limit).
and will result in application crash.