I have a method looks like this:
public void save(DbSession session,Wrappe wrapper,Wrappe wrappe){
//...other logic
//save wrapper
wrapper=(Wrapper)session.save(wrapper)
//set wrapper's id into wrappee
wrappee.setWrapperId(wrapper.getId());
//save wrappee
session.save(wrappee);
}
and test code looks like this:
given:
session.save(_) >> wrapperWithGeneratedId
when:
obj.save(session,wrapper,wrappee)
then:"wrapper got saved"
1*session.save(_) >> {Wrapper save ->
diffs(wrapper,saved)==null
}
and:"wrappee"
1*session.save(_) >> {Wrappe saved ->
diffs(wrappee,saved)==null
}
These test code will give an exception:
java.lang.ClassCastException: java.lang.Boolean cannot be cast to com.company.model.Wrapper
If commented verification closure in "then" section,test will pass,so I guess this section
1*session.save(_) >> {Wrapper save ->
diffs(wrapper,saved)==null
}
overrode this mocking:
session.save(_) >> wrapperWithGeneratedId
Is any way do both correctly?
1st. 'and' is syntactic sugar. It's just a way to visually separate code within the same block. Your last two mocks are effectively the same (although since you're testing behaviorally it will still verify that save is called twice.)
2nd. Assuming you want to verify thatdiffs(wrapper,saved)==null, that won't currently happen because it's not a 'base level' evaluation. Anything within then/where/closures/etc needs to be prepended with 'assert ' if you want to evaluate it.
3rd. A then block is scoped to its when block and can override existing mocks; your assumption that your mock was being overwritten is correct.
4th. Is there any reason you don't just include your return value alongside your evaluation?
2 * session.save(_) >> {Wrapper save ->
diffs(wrapper,saved)==null
return wrapperWithGeneratedId
}
5th. Your error is due to your mock returning a boolean (your assertion logic) which Groovy then tries (and fails) to parse into a Wrapper. My assumption for why this is happening is that .save() has a return type of Wrapper. To fix that you will either need to create a boolean constructor for Wrapper, or change your mock to return something Groovy can turn into a Wrapper (how-to in point 4)
Official Stub/Mock/Spy documentation (quite good, worth a read)
Related
In this method:
datatype Results = Foo | Bar
method test() returns (r:Result)
{
}
Dafny verifies OK and test() returns Foo. Which is technically correct (it does return a value of the correct type) however I was expecting Dafny to complain that the result has not been set by the method itself. What test() is doing is similar to doing:
return;
in a C function that is supposed to return an int.
Is there a way to make Dafny verify that a methods results are always set before the method returns?
The flag you want is /definiteAssignment:2:
/definiteAssignment:<n>
0 - ignores definite-assignment rules; this mode is for testing only--it is
not sound
1 (default) - enforces definite-assignment rules for compiled variables and fields
whose types do not support auto-initialization and for ghost variables
and fields whose type is possibly empty
2 - enforces definite-assignment for all non-yield-parameter
variables and fields, regardless of their types
3 - like 2, but also performs checks in the compiler that no nondeterministic
statements are used; thus, a program that passes at this level 3 is one
that the language guarantees that values seen during execution will be
the same in every run of the program
This is what Dafny says on your code says with that flag:
test.dfy(5,0): Error: out-parameter 'r', which is subject to definite-assignment rules, might be uninitialized at this return point
I am trying to migrate from RxJava1 to RxJava2. I am replacing all code parts where I previously had Observable<Void> to Compleatable. However I ran into one problem with order of stream calls. When I previously was dealing with Observables and using maps and flatMaps the code worked 'as expected'. However the andthen() operator seems to work a little bit differently. Here is a sample code to simplify the problem itself.
public Single<String> getString() {
Log.d("Starting flow..")
return getCompletable().andThen(getSingle());
}
public Completable getCompletable() {
Log.d("calling getCompletable");
return Completable.create(e -> {
Log.d("doing actuall completable work");
e.onComplete();
}
);
}
public Single<String> getSingle() {
Log.d("calling getSingle");
if(conditionBasedOnActualCompletableWork) {
return getSingleA();
}else{
return getSingleB();
}
}
What I see in the logs in the end is :
1-> Log.d("Starting flow..")
2-> Log.d("calling getCompletable");
3-> Log.d("calling getSingle");
4-> Log.d("doing actuall completable work");
And as you can probably figure out I would expect line 4 to be called before line 3 (afterwards the name of andthen() operator suggest that the code would be called 'after' Completable finishes it's job). Previously I was creating the Observable<Void> using the Async.toAsync() operator and the method which is now called getSingle was in flatMap stream - it worked like I expected it to, so Log 4 would appear before 3. Now I tried changing the way the Compleatable is created - like using fromAction or fromCallable but it behaves the same. I also couldn't find any other operator to replace andthen(). To underline - the method must be a Completable since it doesn't have any thing meaning full to return - it changes the app preferences and other settings (and is used like that globally mostly working 'as expected') and those changes are needed later in the stream. I also tried to wrap getSingle() method to somehow create a Single and move the if statement inside the create block but I don't know how to use getSingleA/B() methods inside there. And I need to use them as they have their complexity of their own and it doesn't make sense to duplicate the code. Any one have any idea how to modify this in RxJava2 so it behaves the same? There are multiple places where I rely on a Compleatable job to finish before moving forward with the stream (like refreshing session token, updating db, preferences etc. - no problem in RxJava1 using flatMap).
You can use defer:
getCompletable().andThen(Single.defer(() -> getSingle()))
That way, you don't execute the contents of getSingle() immediately but only when the Completablecompletes and andThen switches to the Single.
We need to be able to rollback a complex transaction in a service, without throwing an exception to the caller. My understanding is that the only way to achieve this is to use withTransaction.
The question is:
why do I have to call this on a domain object, such as Books.withTransaction
What if there is no relevant domain object, what is the consequence of picking a random one?
Below is more or less what I am trying to do. The use case is for withdrawing from an account and putting it onto a credit card. If the transfer fails, we want to rollback the transaction, but not the payment record log, which must be committed in a separate transaction (using RequiresNew). In any case, the service method must return a complex object, not an exception.
someService.groovy
Class SomeService {
#NotTransactional
SomeComplexObject someMethod() {
SomeDomainObject.withTransaction{ status ->
DomainObject ob1 = new DomainObject.save()
LogDomainObject ob2 = insertAndCommitLogInNewTransaction()
SomeComplexObject ob3 = someAction()
if (!ob3.worked) {
status.setRollbackOnly() // only rollback ob1, not ob2!
}
return ob3
}
}
}
The above is flawed - I assume "return ob3" wont return ob3 from the method, as its in a closure. Not sure how to communicate from inside a closure to outside it.
To your primary question: you can pick a random domain object if you want, it won't do any harm. Or, if you prefer, you can find the current session and open a transaction on that instead:
grailsApplication.sessionFactory.currentSession.withTransaction { /* Do the things */ }
Stylistically I don't have a preference here. Others might.
Not sure how to communicate from inside a closure to outside it.
In general this could be hard; withTransaction could in principle return anything it wants, no matter what its closure argument returns. But it turns out that withTransaction returns the value returned by its closure. Here, watch:
groovy> println(MyDomainObject.withTransaction { 2 + 2 })
4
By convention, all withFoo methods which take a closure should work this way, precisely so that you can do the thing you're trying to do.
I'm assuming this question was from a grails 2 application and this problem from 2015 has been fixed before now.
I can't find this in any of the grails 2 documentation, but services have a magic transactionStatus variable injected into their methods. (at least in grails 2.3.11)
You can just leave all the annotations off and use that injected variable.
Class SomeService {
SomeComplexObject someMethod() {
DomainObject ob1 = new DomainObject.save()
LogDomainObject ob2 = insertAndCommitLogInNewTransaction()
SomeComplexObject ob3 = someAction()
if (!ob3.worked) {
transactionStatus.setRollbackOnly() // transactionStatus is magically injected.
}
return ob3
}
}
This feature is in grails 2, but not documented. It is documented in grails 3.
https://docs.grails.org/latest/guide/services.html#declarativeTransactions
search for transactionStatus.
In a controller I have this finder
User.findByEmail('test#test.com')
And works.
Works even if I write
User.findByEmail(null)
But if i write
User.findByEmail(session.email)
and session.email is not defined (ergo is null) it throw exception
groovy.lang.MissingMethodException: No signature of method: myapp.User.findByEmail() is applicable for argument types: () values: []
Is this behavior right?
If i evaluate "session.email" it give me null so I think it must work as it do when I write
User.findByEmail(null)
Even more strange....
If I run this code in groovy console:
import myapp.User
User.findByEmail(null)
It return a user that has null email but if I run the same code a second time it return
groovy.lang.MissingMethodException: No signature of method: myapp.User.findByEmail() is applicable for argument types: () values: []
You can't use standard findBySomething dynamic finders to search for null values, you need to use the findBySomethingIsNull version instead. Try
def user = (session.email ? User.findByEmail(session.email)
: User.findByEmailIsNull())
Note that even if User.findByEmail(null) worked correctly every time, it would not necessarily give you the correct results on all databases as a findBySomething(null) would translate to
WHERE something = null
in the underlying SQL query, and according to the SQL spec null is not equal to anything else (not even to null). You have to use something is null in SQL to match null values, which is what findBySomethingIsNull() translates to.
You could write a static utility method in the User class to gather this check into one place
public static User byOptEmail(val) {
if(val == null) {
return User.findByEmailIsNull()
}
User.findByEmail(val)
}
and then use User.byOptEmail(session.email) in your controllers.
Jeff Brown from grails nabble forum has identified my problem. It's a GORM bug. see jira
More info on this thread
This jira too
I tried with debugger and it looks it should be working, as you write. Maybe the groovy itself is a little bit confused here, try to help it this way:
User.findByEmail( session['email'] )
I'm trying to call a method on a grails service from a controller, but it looks like execution is just skipping the method call.
I've tried debugging the application with a breakpoint inside the method but it is never hit.
My service (generated with grails create-service) is:
class FormatterService {
static transactional = false
def formatList (List<Host>, String fmt) {
OutputObject somePOGO = new OutputObject();
(snip)
return somePOGO
}
}
Then on my controller I have:
class HostController {
def formatterService
def getHostsByLabels = {
(snip)
OutputObject o = formatterService.formatList(someHosts,params.format)
(snip)
}
}
When the formatterService.formatList method should be called in the controller, execution simply skips to the next line, no output is printed to the console and breakpoints within the method are not hit. The OutputObject o reference is null afterward.
What is wrong here? It could be a really basic mistake from my part, but I just can't put my finger on it...
To Me it seems a MetaProgramming Disaster..
Well there are 3 Tests to Debug:
_1) first try to do
println formatterService
println formatterService.getClass()
just to check if its injected bean is the desired one, some plugins sometimes inject beans which overrides the default.
_2) Make sure that the method with a name "formatList" is not injected in your services through metaprogramming by any plugin or core code.
How to test this is simple: Just change the name of the method to some Unrealistic One, ex: "formatListabcdewdw" and then call that one. If it works then its method overriden issue.
and if you are more enthusiastic you can see the metaMethods by
println formatterService.metaClass.methods
_3) just try to do "params.format as String" as the last argument in the method call.\
.
Hope any of these helps, please Do let me know of the findings, i am curious to know.. :)
I found the issue. It has to do with the method signature.
Printing out the thrown exception's message, it says:
No signature of method: hms.FormatterService.formatList() is applicable for argument types: (java.util.TreeSet, java.lang.String) values: (...)
Possible solutions: formatList(java.util.List, java.lang.String)
So, a rookie mistake (wanting to pass a TreeSet for a List) aided by weak typing in Groovy... :P
I've changed the method signature to
def formatList ( items, String fmt) {
and call it as
def activeHosts = ...
OutputObject o = formatterService.formatList(activeHosts, params.format as String)
and now it works.