Let's say I push new code to the Worklight server for purposes of a Direct Update. Can I allow users to still use the application for a set amount time before they actually have to accept the update or is the application essentially unavailable to them until they download the new code?
If you are developing your application using Worklight 6.2, then you as a developer can take over the entire Direct Update flow and can essentially decide how to handle a received update from the server.
Note that by taking full control, you own the flow end-to-end; the default Worklight framework handling will not be available and the full responsibility is on the developer to ensure the validity of every step.
You can read more about customizing Direct Update, here:
Initial reading, starting slide #14: http://public.dhe.ibm.com/software/mobile-solutions/worklight/docs/v620/05_06_Using_Direct_Update_to_quickly_update_your_application.pdf
In depth reading: http://www-01.ibm.com/support/knowledgecenter/SSZH4A_6.2.0/com.ibm.worklight.dev.doc/dev/c_customizing_direct_update_ui_android_wp8_ios.html
In your scenario, I think you could probably go in a less extreme way and just do some tweaks before letting the Worklight framework handle the update from the server. Meaning, you could use the example provided in the training module (slide #18 from the PDF above), where you intercept the update:
wl_directUpdateChallengeHandler.handleDirectUpdate = function(directUpdateData,
directUpdateContext) {
... // display message or counter
}
And display a message and start a counter, and when time's up just directUpdateContext.start(); the update.
Related
hi
I want to build a control panel for a web art application that needs to run in fullscreen, so all this panel, that controls stuff like colors and speed values, have to be located at a different window.
My idea is to have a database storing all these values and when I make a change in the control panel window the corresponding variable in the application window gets updated too. So, it's basically a real-time update that I could do with AJAX setting a interval to keep checking for changes BUT my problem is: I can't wait 30 seconds or so for the update to happen and I guess a every-1-second AJAX request would be impossible.
Final question: is there a way to create a sort of a listener to changes in the database and fire the update event in the main application only immediately after I change some value in the control panel? Does Angular or another framework have this capability?
(Sorry for the long explanation, but I hope my question is clearer by offering the context [: )
A web socket powered application would have this benefit. This carries a bit more complexity on the back end, but has the benefit of making your application as close to real-time as can be reasonably expected.
The Mozilla Development Network has some good documentation on websockets.
On the front end, the WebSocket object should work for you on most modern browsers.
I'm not sure what your back end is written in, but Socket.IO for Node.js and Tornado for Python will make your applications web-socket capable
If one window is opening the other windows via JavaScript, you can keep the reference to the opened window and use otherWindow.postMessage to pass messages across
"Parent" window looks like
// set up to receive messages
window.addEventListener('message', function (e) {
if (e.origin !== 'http://my.url')
return; // ignore unknown source
console.log(e.message);
});
// set up to send messages
var otherWindow = window.open('/foo', '_blank');
otherWindow.postMessage('hello world', 'http://my.url');
"Child" windows look similar
// same setup to recieve
// ...
// set up to send
var otherWindow = window.opener;
// ... same as before
For the realtime I would recommend using a library like socket.io or using a database like firebase.
For the fullscreen I would recommend using a library like angular-screenfull
i use https://pushjs.io/, had exactly the same problem and this is a really simple solution for your problem. It is capable of sending and listening to events without any database interference.
We are developing an SAP Fiori App to be used on the Launchpad and as an offline-enabled hybrid app as well using the SAP SDK and its Kapsel Plug Ins. One issue we are facing at the moment is the ODATA message handling.
On the Gateway, we are using the Message Manager to add additional information to the response
" ABAP snippet, random Gateway entity method
[...]
DATA(lo_message_container) = me->mo_context->get_message_container( ).
lo_message_container->add_message(
iv_msg_type = /iwbep/cl_cos_logger=>warning
iv_msg_number = '123'
iv_msg_id = 'ZFOO'
).
" optional, only used for 'true' errors
RAISE EXCEPTION TYPE /iwbep/cx_mgw_busi_exception
EXPORTING
message_container = lo_message_container.
In the Fiori app, we can directly access those data from the message manager. The data can be applied to a MessageView control.
// Fiori part (Desktop, online)
var aMessageData = sap.ui.getCore().getMessageManager().getMessageModel().getData();
However, our offline app always has an empty message model. After a sync or flush, the message model is always empty - even after triggering message generating methods in the backend.
The only way to get some kind of messages is to raise a /iwbep/cx_mgw_busi_exception and pass the message container. The messages can be found, in an unparsed state, in the /ErrorArchive entity and be read for further use.
// Hybrid App part, offline, after sync and flush
this.getModel().read("/ErrorArchive", { success: .... })
This approach limits us to negative, "exception worthy", messages only. We also have to code some parts of our app twice (Desktop vs. Offlne App).
So: Is there a "proper" to access those messages after an offline sync and flush?
For analyzing the issue, you might use the tool ILOData as seen in this blog:
Step by Step with the SAP Cloud Platform SDK for Android — Part 6c — Using ILOData
Note, ILOData is part of the Kapsel SDK, so while the blog above was part of a series on the SAP Cloud Platform SDK for Android, it also applies to Kapsel apps.
ILOData is a command line based tool that lets you execute OData requests and queries against an offline store.
It functions as an offline OData client, without the need for an application.
Therefore, it’s a good tool to use to test data from the backend system, as well as verify app behavior.
If a client has a problem with some entries on their device, the offline store from the device can be retrieved using the sendStore method and then ILOData can be used to query the database.
This blog about Kapsel Offline OData plugin might also be helpful.
Is it possible to write a plugin for Glimpse's existing SQL tab?
I'm trying to log my SQL queries and the currently available extensions don't support our in-house SQL libary. I have written a custom plugin which logs what I want, but it has limited functionality and it doesn't integrate with the existing SQL tab.
Currently, I'm logging to my custom plugin using a single helper method inside my DAL's base class. This function looks takes the SqlCommand and Duration in order to show data on my custom tab:
// simplified example:
Stopwatch sw = Stopwatch.StartNew();
sqlCommand.Connection = sqlConnection;
sqlConnection.Open();
object result = sqlCommand.ExecuteScalar();
sqlConnection.Close();
sw.Stop();
long duration = sw.ElapsedMilliseconds;
LogSqlActivity(sqlCommand, null, duration);
This works well on my 'custom' tab but unfortunately means I don't get metrics shown on Glimpse's HUD:
Is there a way I can provide Glimpse directly with the info it needs (in terms of method names, and parameters) so it displays natively on the SQL tab?
The following advise is based on the fact that you can't use DbProviderFactory and you can't use a proxied SqlCommand, etc.
The data that appears in the "out-of-the-box" SQL tab is based on messages of given types been published through our internal Message Broker (see below on information on this). Because of the above limitations in your case, to get things lighting up correctly (i.e. your data showing up in HUD and the SQL tab), you will need to simulate the work that we do under the covers when we publish these messages. This shouldn't be that difficult and once done, should just work moving forward.
If you have a look at the various proxies we have here you will be above to see what messages we publish in what circumstances. Here are some highlights:
DbCommand
Log command start - here
Log command error - here
Log command end - here
DbConnection:
Log connection open - here
Log connection closed - here
DbTransaction
Log Started - here
Log committed - here
Log rollback - here
Other
Command row count here - Glimpses calculates this at the DbDataReader level but you could do it elsewhere as well
Now that you have an idea of what messages we are expecting and how we generate them, as long as you pass in the right data when you publish those messages, everything should just light up - if you are interested here is the code that looks for the messages that you will be publishing.
Message Broker: If you at the GlimpseConfiguration here you will see how to access the Broker. This can be done statically if needed (as we do here). From here you can publish the messages you need.
Helpers: For generating some of the above messages, you can use the helpers inside the Support class here. I would have shifted all the code for publishing the actual messages to this class, but I didn't think there would be too many people doing what you are doing.
Update 1
Starting point: With the above approach you shouldn't need to write your own plugin. You should just be able to access the broker GlimpseConfiguration.GetConfiguredMessageBroker() (make sure you check if its null, which it is if Glimpse is turned off, etc) and publish your messages.
I would imagine that you would put the inspection that leverages the broker and published the messages, where ever you have knowledge of the information that needs to be collected (i.e. inside your custom lib). Normally this would require references inside your lib to glimpse (which you may not want), so to protect against this, from your lib, you would call a proxy (which could be another VS proj) that has the glimpse dependency. Hence your ado lib only has references to your own code.
To get your toes wet, try just publishing a couple of fake connection and command messages. Assuming the broker you get from GlimpseConfiguration.GetConfiguredMessageBroker() isn't null, these should just show up. Then you can work towards getting real data into it from your lib.
Update 2
Obsolete Broker Access
Its marked as obsolete because its going to change in v2. You will still be able to do what you need to do, but the way of accessing the broker has changed. For what you currently need to do this is ok.
Sometimes null
As you have found this is really dependent on where in the page lifecycle you are currently at. To get around this, I would probably change my original recommendation a little.
In the code where you are currently creating messages and pushing them to the message bus, try putting them into HttpContext.Current.Items. If you haven't used it before, this is a store which asp.net provides out of the box which lasts the lifetime of a given request. You could have a list that you put in there, still create the message objects that you are doing, but put them into that list instead of pushing them through the broker.
Then, create a HttpModule (its really simple to do) which taps into the PostLogRequest event. Within this handler, you would pull the list out of the context, iterate through it and push the message into the message broker (accessing the same way you have been).
Worklight 6.1 on both Windows (colleague) and Mac (me), building an a Hybrid app destined for Android device but to speed up development we do initial testing as Mobile Web App in Chrome browser on desktop.
We get a weird symptom that I'm trying to fine-down to a reproducible test case. I think I see different behaviours when stepping in debugger and just letting it run. Want to check whether a certain coding pattern could be the cause of the symptom before I go any further.
Fundamental question: should we wait for the resolution of a promise returned by a JSONSTore request for an action on a collection before issuing another request? more explanation below.
The overall intent is to load some data into the JSONStore, with some intelligent replace/merge action if a record is already present. Pseudo code:
for each record retrieved from back-end
if ( record already present in Store )
do some data merging
replace record
else
add record
The application code actually works like this, just considering the add() case, the problem manifests when the store is empty, all records need to be added
for each record to add
addPromise = store.get().add(record);
listOfPromises.insert(addPromise);
examine the list of promises recording any errors
That is there is no "wait" for add to finish before issuing the next add request. Hence in effect we've initiated a set of adds "in parallel" whatever that might mean in JavaScript in Chrome.
The code appears to run just fine, no errors reported. On android device it works reliably. In Chrome under normal running (no stepping in debugger) we end up with no reported errors but only one record inserted - indeed as though a snapshot of the initial "empty" store had been taken and each add is working on that "empty" copy.
After writing this I'm now pretty convinced that the coding pattern described above is vulnerable to a kind of race and that the better approach is build a list of documents to be added and insert them in a single operation.
A more detailed answer will be coming later, but I now know that this
the coding pattern described above is vulnerable to a kind of race and
that the better approach is build a list of documents to be added and
insert them in a single operation.
is true. In the browser the JSONStore does require that we wait for the result of one request before issuing another one. The recommended approach is
var dataToAdd = buildArrayOfDataToAdd(responseFromServer);
var dataToReplace = buildArrayOfDataToReplace(responseFromServer);
jsonstore.add( dataToAdd ).then( function() { jsonstore.replace( dataToReplace); })
I have this requirement : My WL application have a set of static pages that might be updated any time. Originally the source of all static content is a desktop page that will be transformed by xsl to a mobile friendly content. The problem that I don't want to do that on each request (HA requirement).
I want to get some inspiration on how to architect that without using direct update mechanism (don't want the end user to get notified of these updates).
I should note that pages will change rarely every few month maybe.
I'm thinking about 2 ways of doing that :
1- Making the transformation on adapter side and rely on WL caching so that transformation is not made each time (does that exist ?). But how the adapter will get notified of page change and flush the cache ? Should I program some advanced java based adapter ? (Storing in the cache and having a kind of a job that scans every day for content changes ?)
2- Doing it mobile side but I don't know how to get notified of changes !
Is your only problem with Worklight's Direct Update that the user is being notified and is required to explicitly approve the transfer?
In this case why not use the option of Silent Direct Update?
The property you're looking for is updateSliently set to true in initOptions.js.
For this to work it is required, obviously, that connectOnStartup will be set to true as well.
perhaps what is doable is to use an adapter to fetch the HTML (or whatever it is) and save it to the device's local storage and then have the app display this content, this way you do not alter the app's web resources and not trigger Direct Update.