I have not seen any discussion or awareness so far that Firebase does in fact make available a unique identifier--in fact the full URL--to each specific data record via their "snapshot" which they return, i.e. the wrapper around the data record (accessed via snapshot.val()). By doing a basic property examination of the snapshot I discovered that the unique URL is available (see examples below). However, it seems that, for some reason, Firebase keeps changing the name of the key every few days, causing my application to break. I have to go in and re-discover the new URL property key and change it so that it will work again.
Here are three examples of how I have seen the key change so far. Each value is the same, but the key keeps changing over time (i.e.: "Wb", "Xb", "bc").:
getMemberBySnapshot - snapshot has prop Wb with value https://prototype1.firebaseio.com/users/-IwohKfw1l5F3gFqyJJ5
getMemberBySnapshot - snapshot has prop Xb with value https://prototype1.firebaseio.com/users/-IwohKfw1l5F3gFqyJJ5
getMemberBySnapshot - snapshot has prop bc with value https://prototype1.firebaseio.com/users/-IwohKfw1l5F3gFqyJJ5
I have read Firebase's suggestions that developers should use an email address if they want a unique key (what if my model does not use an email field? What if a user wants to change their email?), or Firebase suggests altenatively to retrieve all existing records and then search through them on the client. Neither of these solutions are satisfying. But I'm seeing that they do provide the unique URL to each data record in the 'snapshot'. Why do they not provide a stabilized key so that a developer can call it consistently???
Firebase.js is a compiled script. The names of internal variables will change every time we compile it and release a new version, so you should definitely not be relying on any properties that are not documented on our website.
For your specific case, you should be using:
snapshot.ref().toString()
in order to get the URL.
Related
I would like to understand better Firebase Dynamic Links because i am very new to this subject.
What i would like to know :
FirebaseDynamicLinks.instance.getInitialLink() is supposed to return "only" the last dynamic link created with the "initial" url (before it was shorten) ?
Or why FirebaseDynamicLinks.instance.getInitialLink() doesn't take a String url as a parameter ?
FirebaseDynamicLinks.instance.getDynamicLink(String url) doesn't read custom parameters if the url was shorten, so how can we retrieve custom parameters from a shorten link ?
My use case is quite simple, i am trying to share an object through messages in my application, so i want to save the dynamic link in my database and be able to read it to run a query according to specific parameters.
FirebaseDynamicLinks.instance.getInitialLink() returns the link that opened the app and if the app was not opened by a dynamic link, then it will return null.
Future<PendingDynamicLinkData?> getInitialLink()
Attempts to retrieve the dynamic link which launched the app.
This method always returns a Future. That Future completes to null if
there is no pending dynamic link or any call to this method after the
the first attempt.
https://pub.dev/documentation/firebase_dynamic_links/latest/firebase_dynamic_links/FirebaseDynamicLinks/getInitialLink.html
FirebaseDynamicLinks.instance.getInitialLink() does not accept a string url as parameter because it is just meant to return the link that opened the app.
Looks like there's no straightforward answer to getting the query parameters back from a shortened link. Take a look at this discussion to see if any of the workarounds fit your use case.
So I am trying to make a calendar app in ionic and I want to store events, if a user makes one, I looked at the ionic documentation, and it makes it seem too simple I basically copied exactly what they have with a few adjustments and I do not know how to test it. Here is what I have:
save() {
var n = 0
this.event.startTime = new Date(this.readDescription())
this.storage.set('fooditem'+this.increaseVal(),this.event);
this.modalCtrl.dismiss({event: this.event})
}
increaseVal() function just increments the key name so I have a new key for every new value (this is a temporary fix)
I know I probably need to get the data stored after it has been saved but I just need to make sure it actually saves
I'm answering this question with the assumption that you want to know where the data is being stored & to see the value at that location.
Ionic Storage gives options to use SQLite, IndexedDB, WebSQL and localstorage as ways to store data on the device. With the first 3, there is no way to access the data besides fetching it. Local Storage however, is accessible in Chrome Dev Tools > Application > Local Storage
Ionic Storage allows the developer to configure the driver used to store data by specifying it in the driverOrder options in App Module. Simply put localstorage as the first value in this as such driverOrder: ['localstorage', 'indexeddb', 'sqlite', 'websql'] to force the app to store data in localstorage and then you can see the value stored in the location described above.
Below url is used for fetching analytics data related to firebase dynamic links:
https://firebasedynamiclinks.googleapis.com/v1/SHORT_DYNAMIC_LINK/linkStats?durationDays=DURATION
(Please note that the above url is an API that needs authentication/token. You can't open it in a browser. Also, SHORT_DYNAMIC_LINK and DURATION are just placeholders not actual parameter values.
The reason I have added a link is because my question is about the value of the placeholder - DURATION present in the link)
DURATION tells how many days(going backwards) worth data needs to be fetched.
My requirement is to fetch data from the start(when the dynamic link was created). So, what value should I set for durationDays to achieve that?
As a workaround I can set a big number(like 1000 days) but wanted to know a proper way.
Based on what I tried, the parameter durationDays must be present in the url, otherwise the request would return 400 INVALID ARGUMENT. Even setting DURATION values to 0 or -1 return a similar error.
Firebase Analytics API Doc: https://firebase.google.com/docs/reference/dynamic-links/analytics
I am using Change Feed processor library to read the Change Feed on a partitioned collection and below is the code for how I have configure it. I ma using most of the default options.
ChangeFeedProcessorOptions feedProcessorOptions = new
{
LeaseRenewInterval = TimeSpan.FromSeconds(15),
};
var docObserverFactory = DocumentFeedObserverFactory.Create(this.destinationCollectionInfo, this.dbRepository);
this.builder
.WithHostName(hostName)
.WithFeedCollection(this.monitoredCollectionInfo)
.WithLeaseCollection(this.leaseCollectionInfo)
.WithProcessorOptions(feedProcessorOptions)
.WithObserverFactory(docObserverFactory);
This runs fine as long as the Change Feed application is running and documents are being inserted/updated in the collection and the Change Feed app picks them up as expected.
The problem happens when I stop the Change Feed app for sometime and insert/update few documents in the Collection. Then when I start the Change Feed app, it doesn't pick changes from where it last left. Those changes that were inserted when the Change Feed app was stopped are lost. But when I set the flag StartFromBeginning to true, it picks everything from the start including changes that were inserted when the Change Feed app was stopped in between for sometime.
My understanding of read from current (StartFromBeginning to false) is that the Change Feed reads documents since it last left. But that doesn't seem to happen. Please help.
There are two ways to continue from exactly where you left it.
The first, and more accurate one, is to store the Continuation token of the last thing you read. That way you can specify it when you start again and it will win over both the StartTime and the StartFromBeginning flags.
The second one is to provide the StartTime property which will try and find the continuation token of a given time automatically. It has an approximate 5 second precision so there is a chance that you might miss some documents though.
I want to customize the standard drill-down functionality and add a text parameter to the drill-down URL. I will then parse and use the parameter in the SysStartUpCmdDrillDown or EventDrillDownPoller class like the solution provided by Jan B. Kjeldsen in this question.
The standard drill-down link is dynamics://Target/?DrillDown_RecID/ :
dynamics://0/?DrillDown_5637230378/
In previous versions of AX it was possible to modify the RecId to custom text and parse the text once the client is started:
dynamics://0/?DrillDown_0MenuItemName=PurchTable&FieldName=PurchId&FieldValue=P000044
Unfortunately, in AX 2012 the RecId is checked before the client is started and if it is not a valid int64, the drill-down event is not sent to the client. Since it is not possible to change the RecId to anything other than an integer, #Alex Kwitny suggested in the comments at that same question that you can add the custom text to the drill-down target like this:
dynamics://0MenuItemName=PurchTable/?DrillDown_5637230378/
The problem I experience with this is that the link now gets confused about which instance to start.
If the target is equal to the value in the System Admin -> system parameters -> Alerts ->Drill-down target, a client with the correct server instance is started. When I append the text with my custom text, it always starts the default instance(Which could be different from the instance I intended to start). While this is not ideal, I could work around this issue.
The bigger problem is that it now always starts a new session of the default instance, even if a client session is already started. As far as I can see I cannot write X++ code to solve this issue since the server instance is determined before any code in the client is executed.
My question is this - How can I add custom text to the drill-down link while preserving the way the client instance is started: If a client for the instance is already open, it should process the link in the open client, and not start up a new client of the default instance.
You should probably come up with another solution as mentioned in this post, but there could still be a way.
The URL has two objects that can be modified:
dynamics://[Drill-down target(str)]/?Drilldown_[Int64]
According to you, if you modify the [Drill-down target], then it launches AX using the default client config, and that is behavior that you don't want. If you have a matching [Drill-down target], it'll launch in the open client window, which is behavior I can't confirm, but I'll take it at face value and assume you're correct.
So that means the only thing you can modify in the URL is [int64]. This is actually a string that is converted to an int64 via str2int64(...), which in turn corresponds to a RecId. This is where it gets interesting.
This work all happens in \Classes\SysStartUpCmdDrillDown\infoRun.
Well, lucky for you the ranges for the objects are:
RecId - 0 to 9223372036854775807
Int64 - -9223372036854775808 to 9223372036854775807
You can call minRecId() and maxRecId() to confirm this.
So this means you have -9223372036854775808 to -1 numbers to work with by calling URLs in this range:
dynamics://0/?DrillDown_-1
to
dynamics://0/?DrillDown_-9223372036854775808
Then you would modify \Classes\SysStartUpCmdDrillDown\infoRun to look for negative numbers, and fork to your custom code.
HOW you decide to user these negative #'s is up to you. You can have the first n-digits be a table id or a look-up value for a custom table. You can't technically use a RecId as part of that negative number because in theory the RecId could get up that high (minus 1).