how can i start Flux after completion of Flux? Flux doesn't depend on result of Flux.
I thought operation then() should do the work, but it just return mono. So what is the correct operator?
Flux.thenMany is the operator that you need
abstract Flux<Integer> flux1();
abstract Flux<String> flux2();
public Flux<String> flux2AfterFlux1(){
return flux1().thenMany(flux2());
}
My reply is late, so you have probably either figured this out, or moved on. I need to do the same thing, so I seem to have achieved this by using Flux.usingWhen(). I need to obtain IDs from my database that exhibit a certain property. After retrieving these IDs, then I need to get some information about these IDs. Normally, a join would work, but I am using MongoDB, and joins are horrible, so it is better to do separate, sequential queries. So let's say I have a Mongo reactive repository with a method called Flux<String> findInterestingIds(). I have another method in the same repository called Flux<String> findInterestingInformation(String[] interestingIds) that I need to feed the IDs found in the call to the previous method. So this is how I handle it:
Mono<List<String>> interestingIdsMono = myRepo.findInterestingIds()
.collectList();
Flux.usingWhen(interestingIdsMono,
interestingIds -> myRepo.findInterestingInformation(interestingIds),
interestingIds -> Flux.empty().doOnComplete(() -> log.debug("Complete"));
The cleanup function (third parameter) was something that I don't quite yet understand how to use in a good way, so I just logged completion and I do not need to emit anything extra when the flux completes.
ProjectReactor used to have a compose function that is now called transformDeferred, and I had some hopes for that, but I do not quite see how it would apply in this type of situation. At any rate, this is my attempt at it, so feel free to show me a better way!
Related
Is it supposed to be any difference on running this two codes?
ref.on('child_added',function(child,prev){
console.log(child.key+prev);
}
ref.off();
and
ref.once('child_added',function(child,prev){
console.log(child.key+prev);
}
I've been surprised that the second one doesn't iterates between the childs!
What am I doing wrong here (edited->)to obtain a complete list of the childs?
When you use once, you're asking for a single event of the indicated type. So once("child_added" fires a single child_added event.
The fact that your on fires multiple times, is likely a race condition because of the way you ordered the calls. I'd expect this to also invoke only once:
ref.on('child_added',function(child,prev){
console.log(child.key+prev);
ref.off();
}
But I must admit this is pretty uncommon, so I don't think I ever tested it.
In addition to #Puf's answer I would add this quote from documentation you should be aware:
Add queries to limit the data that your listen operations return and
use listeners that only download updates to data — for example, on()
instead of once(). Reserve .once() for actions that truly don’t
require data updates.
Source: https://firebase.google.com/docs/database/usage/optimize
Another usefull link: https://firebase.google.com/docs/database/usage/billing
I have the need to construct a WorkflowTaskQuery with a custom workflow model date as criteria. The criteria needs to be "currentDate >= myCustomDate".
I have noticed that it is possible to add custom properties to the WorkflowTaskQuery but looking into the implementation it seems like those properties all are added as equals-criterias. (reference(4.2.x): org.alfresco.repo.workflow.activiti.ActivitiWorkflowEngine.addTaskPropertiesToQuery)
To get all active tasks and do the filtering on the returned result will not be a good approach since there will be thousands of running workflow tasks in this implementation.
The only other approach I can think of would be to subclass both WorkflowTaskQuery and ActivitiWorkflowEngine and rewrite some private methods (like createRuntimeTaskQuery) and handle my special cases on my own there. (Activiti has methods like greaterThan and so on when searching for tasks based on variables....)
If anyone have any better suggestions, please feel free to share them with me :)
We are implementing a solution that drives Activiti using the Rest interface and have successfully implemented task queries using the POST /rest/service/query/task
The body of the request contains the conditions and the operator to use in query can have the following values: "equals", "notEquals", "equalsIgnoreCase", "notEqualsIgnoreCase", "lessThan", "greaterThan", "lessThanOrEquals", "greaterThanOrEquals" and "like".
Now, with that said.....I'm not sure I understand your query.
currentData >= customDate, obviously currentDate is self explanatory, but is customDate a process instance variable or a task local variable? It may impact the format of the query.
In Meteor, I got a collection that the client subscribes to. In some cases, instead of publishing the documents that exists in the collection on the server, I want to send down some bogus data. Now that's fine using the this.added function in the publish.
My problem is that I want to treat the bogus doc as if it were a real document, specifically this gets troublesome when I want to update it. For the real docs I run a RealDocs.update but when doing that on the bogus doc it fails since there is no representation of it on the server (and I'd like to keep it that way).
A collection API that allowed me to pass something like local = true this would be fantastic but I have no idea how difficult that would be to implement and I'm not to fond of modifying the core code.
Right now I'm stuck at either creating a BogusDocs = new Meteor.Collection(null) but that makes populating the Collection more difficult since I have to either hard code fixtures in the client code or use a method to get the data from the server and I have to make sure I call BogusDocs.update instead of RealDocs.update as soon as I'm dealing with bogus data.
Maybe I could actually insert the data on the server and make sure it's removed later, but the data really has nothing to do with the server side collection so I'd rather avoid that.
Any thoughts on how to approach this problem?
After some further investigation (the evented mind site) it turns out that one can modify the local collection without making calls to the server. This is done by running the same methods as you usually would, but on MyCollection._collection instead of just on Collection. MyCollection.update() would thus become MyCollection._collection.update(). So, using a simple wrapper one can pass in the usual arguments to a update call to update the collection as usual (which will try to call the server which in turn will trigger your allow/deny rules) or we can add 'local' as the last argument to only perform the update in the client collection. Something like this should do it.
DocsUpdateWrapper = function() {
var lastIndex = arguments.length -1;
if (arguments[lastIndex] === 'local') {
Docs._collection.update(arguments.slice(0, lastIndex);
} else {
Docs.update(arguments)
}
}
(This could of course be extended to a DocsWrapper that allows for insertion and removals too.)(Didnt try this function yet but it should serve well as an example.)
The biggest benefit of this is imo that we can use the exact same calls to retrieve documents from the local collection, regardless of if they are local or living on the server too. By adding a simple boolean to the doc we can keep track of which documents are only local and which are not (An improved DocsWrapper could check for that bool so we could even omit passing the 'local' argument.) so we know how to update them.
There are some people working on local storage in the browser
https://github.com/awwx/meteor-browser-store
You might be able to adapt some of their ideas to provide "fake" documents.
I would use the transform feature on the collection to make an object that knows what to do with itself (on client). Give it the corruct update method (real/bogus), then call .update rather than a general one.
You can put the code from this.added into the transform process.
You can also set up a local minimongo collection. Insert on callback
#FoundAgents = new Meteor.Collection(null, Agent.transformData )
FoundAgents.remove({})
Meteor.call 'Get_agentsCloseToOffer', me, ping, (err, data) ->
if err
console.log JSON.stringify err,null,2
else
_.each data, (item) ->
FoundAgents.insert item
Maybe this interesting for you as well, I created two examples with native Meteor Local Collections at meteorpad. The first pad shows an example with plain reactive recordset: Sample_Publish_to_Local-Collection. The second will use the collection .observe method to listen to data: Collection.observe().
How can I tell the Closure Compiler not to rename an inner function? E.g., given this code:
function aMeaninglessName() {
function someMeaningfulName() {
}
return someMeaningfulName;
}
...I'm fine with Closure renaming the outer function (I actively want it to, to save space), but I want the function name someMeaningfulName left alone (so that the name shown in call stacks for it is "someMeaningfulName", not "a" or whatever). This despite the fact that the code calling it will be doing so via the reference returned by the factory function, not by the name in the code. E.g., this is purely for debugging support.
Note that I want the function to have that actual name, not be anonymous and assigned to some property using that name, so for instance this is not a duplicate of this other question.
This somewhat obscure use case doesn't seem to be covered by either the externs or exports functionality. (I was kind of hoping there'd be some annotation I could throw at it.) But I'm no Closure Compiler guru, I'm hoping some of you are. Naturally, if there's just no way to do that, that's an acceptable answer.
(The use case is a library that creates functions in response to calls into it. I want to provide a version of the library that's been pre-compressed by Closure with SIMPLE_OPTIMIZATIONS, but if someone is using that copy of the library with their own uncompressed code and single-stepping into the function in a debugger [or other similar operations], I want them to see the meaningful name. I could get around it with eval, or manually edit the compressed result [in fact, the context is sufficiently unique I could throw a sed script at it], but that's awkward and frankly takes us into "not worth bothering" territory, hence looking for a simple, low-maintenance way.)
There is no simple way to do this. You would have to create a custom subclass of the CodingConvention class to indicate that your methods are "local" externs (support for this was added to handle the Prototype library). It is possible that InlineVariables, InlineFunctions, or RemoveUsedVariables will still try to remove the name and would also need to be fixed up.
Another approach is to use the source maps to remap the stack traces to the original source.
read the following section
https://developers.google.com/closure/compiler/docs/api-tutorial3#export
Two options basically, use object['functionName'] = obj.functionName or the better way
use exportSymbol and exportProperty both on the goog object, here is the docs link for that
http://closure-library.googlecode.com/svn/docs/closure_goog_base.js.html
-- edit
ah, i see now, my first answer is not so great for you. The compiler has some interesting flags, the one which might interest you is DEBUG, which you can pass variables into the compiler which will allow you to drop some debugging annotations in via logging or just a string which does nothing since you are using simple mode.
so if you are using closure you can debug against a development version which is just a page built with dependiencies resolved. we also the drop the following in our code
if(DEBUG){
logger.info('pack.age.info.prototype.func');
}
I am kind of confused about which methods belong with and when to use them.
Right now, I am using subscribe for basically everything and it is not working for me when I want a quick static value out of Firebase. Can you explain when I should use subscribe vs other methods other than for a strict observable?
When working with async values you have a few options: promises, rxjs, callbacks. Every option has its own drawbacks.
When you want to retrieve a single async value it is tempting to use promises for their simplicity (.then(myVal => {})). But this does not give you access to things like timeouts/throttling/retry behaviour etc. Rx streams, even for single values do give you these options.
So my recommendation would be, even if you want to have a single value, to use Observables. There is no async option for 'a quick static value out of a remote database'.
If you do not want to use the .subscribe() method there are other options which let you activate your subscription like .toPromise() which might be easier for retrieving a single value using Rx.
const getMyObjPromise = $firebase.get(myObjId)
.timeout(5000)
.retry(3)
.toPromise()
getMyObjPromise.then(obj => console.log('got my object'));
My guess is, that you have a subscribe method that contains a bunch of logic like it was a ’.then’ and you save the result to some local variable.
First: try to avoid any logic inside the subscription-method -> use stream-operators before that and then subscribe just to retrieve the data.
You much more flexible with that and it is much easier to unit-test those single parts of your stream than to test a whole component in itself.
Second: try to avoid using a manual subscriptions at all - in angular controllers they are prone to cause memory leaks if not unsubscribed.
Use the async-pipe instead in your template and let angular manage the subscription itself.