Printing error messages from console instead of closing shiny app - function

I have a shiny app that runs a monte carlo simulation with 500 replications. To do this, I use a for loop and call a function from another package to run the simulation, and then I save the data. The shiny app then produces the results using renderTable.
It is possible that the user could mistakenly enter something that would cause one or more of the replications to fail to converge, triggering a stop in the function I'm calling. If this happens, there is nothing to render in a table. In R, I get a nice error message from the package telling me that the model failed to converge. However, in Shiny, the app just force closes.
I'm currently using tryCatch and showNotification to display this notification in the app (see below):
observeEvent(input$go,
tryCatch({
simulation_results()
},
error = function(err){
showNotification(paste0(err), type = 'err')
})
)
It works well, but the problem is that it causes the app to take 6x longer to run (it goes from ~1.5 min to ~10 min). I think this is because it's trying to catch and show the notification from every individual replication in the for loop. The app also still does close; it just displays the error first (which I do appreciate).
Is there a [faster] way to get shiny to print error messages from the console instead of closing the app?
I was thinking of validate, but I don't know how it would work - what I really need is something like
validate(need("no error message in the console")). I tried using validate(need(simulation_results(),geterrmessage()) to see if it would simply print the last error message if there were no simulation results, but the app shuts down once it gets to the stop error in the function.
Also, I'm using flexdashboard if that changes anything.

Related

How to handle "Unexpected EOF at target" error from API calls?

I'm creating a Forge application which needs to get version information from a BIM 360 hub. Sometimes it works, but sometimes (usually after the code has already been run once this session) I get the following error:
Exception thrown: 'Autodesk.Forge.Client.ApiException' in mscorlib.dll
Additional information: Error calling GetItem: {
"fault":{
"faultstring":"Unexpected EOF at target",
"detail": {
"errorcode":"messaging.adaptors.http.flow.UnexpectedEOFAtTarget"
}
}
}
The above error will be thrown from a call to an api, such as one of these:
dynamic item = await itemApi.GetItemAsync(projectId, itemId);
dynamic folder = await folderApi.GetFolderAsync(projectId, folderId);
var folders = await projectApi.GetProjectTopFoldersAsync(hubId, projectId);
Where the apis are initialized as follows:
ItemsApi itemApi = new ItemsApi();
itemApi.Configuration.AccessToken = Credentials.TokenInternal;
The Ids (such as 'projectId', 'itemId', etc.) don't seem to be any different when this error is thrown and when it isn't, so I'm not sure what is causing the error.
I based my application on the .Net version of this tutorial: http://learnforge.autodesk.io/#/datamanagement/hubs/net
But I adapted it so I can retrieve multiple nodes asynchronously (for example, all of the nodes a user has access to) without changing the jstree. I did this to allow extracting information in the background without disrupting the user's workflow. The main change I made was to add another Route on the server side that calls "GetTreeNodeAsync" (from the tutorial) asynchronously on the root of the tree and then calls it on each of the returned children, then each of their children, and so on. The function waits until all of the nodes are processed using Task.WhenAll, then returns data from each of the nodes to the client;
This means that there could be many api calls running asynchronously, and there might be duplicate api calls if a node was already opened in the jstree and then it's information is requested for the background extraction, or if the background extraction happens more than once. This seems to be when the error is most likely to happen.
I was wondering if anyone else has encountered this error, and if you know what I can do to avoid it, or how to recover when it is caught. Currently, after this error occurs, it seems that every other api call will throw this error as well, and the only way I've found to fix it is to rerun the code (I use Visual Studio so I just rerun the server and client, and my browser launches automatically)
Those are sporadic errors from our apigee router due to latency issues in the authorization process that we are currently looking into internally.
When they occur please cease all your upcoming requests, wait for a few minutes and retry again. Take a look at stuff like this or this to help you out.
And our existing reports calling out similar errors seem to point to concurrency as one of the factors leading up to the issue so you might also want to limit your concurrent requests and see if that mitigate the issue.

google.script.run is NOT running every time it is called. Some times the function runs, other times it does nothing

In Google apps script when using a client sided .HTML file you can call a server sided script using google.script.run.(Function name).
You can see the related documentation here: https://developers.google.com/apps-script/guides/html/reference/run
Now this script has been working with no problems over the first 6 months of its lifetime or so. I have not touched the program and I have not been notified or have located any newly deprecated code.
Over the course of the last couple months however, my users have been reporting that when they finish interacting with the HTML document, nothing happens when they close it and they have to repeat the entire process 3 or sometimes even 4 times before they will get it to go through.,
This means that when the user closes the client sided HTML window, the server sided function should be called to handle the remaining tasks but in some cases is not. This issue is completely random, and does not seem to be caused by anything specific.
I have taken some steps myself to attempt to solve the issue. I have wrapped the entirety of the code in try catch blocks, including the .HTML and .GS files. This means that if literally ANYTHING goes wrong in ANY script, I will be notified of it immediately. However, despite this being the case I am yet to receive any emails of it failing even though I watch it fail with my own eyes. I have added log commands before and after this function to see if it stops working all together or continues. In every case regardless of whether the function call is successful or not the log commands go through.
To me this can only mean that for some reason the function google.script.run is not working properly, and is failing to run the associated function, but is not returning an error message or stopping the script.
I am at an absolute loss since I have no error message, no reproducible steps, and no history of this being a problem before while suddenly starting to get worse and worse over time. I have checked Google's issue tracker to no results. If anyone else is using this function and is having problems I would love you to share your experiences here. If you have a solution please let me know as soon as possible. If I can't fix this issue I am going to have to use a new platform entirely.
Edit 10/2:
After looking further into this issue I have discovered a list of all executions on this project. I can see what functions were executed, when, and how long they took to execute. I can see that when the function that opens the HTML service is ran, the next function that should run does not always appear in the list. And when it doesn't, I can see that the user repeated their steps until it did run. This supports my theory that the function just isn't running when it should be after being called my script.run
Tl;dr: The affected computers are running so slowly that google.script.host.close would run before google.script.run.functionName() is able to be called and the information passed from the client to server, causing the function to never run but also not return an error. Adding Utilities.sleep(1000) fixes the issue.
I'm answering here in the situation that someone stumbles upon this thread in the future because they're having similar problems.
I was able to fix the issue by adding two lines of code between
google.script.run and google.script.host.close.
I added Google's Utilities.sleep(1000) to force the computer to wait one second between executing the function and closing the HTML window. I also added an HTML alert that shows that the function was called and didn't suffer from a runtime error.
I don't know exactly why this seems to have fixed the issue but I have a theory.
I have about 20 computers this spreadsheet runs on. Only about 6 of them were having the issue, and this wasn't brought to my attention until recently. As it turns out the 6 computers that were having the issue were the slowest computers of the bunch.
My theory is that the computers were so slow, and the internet bandwidth was fluctuating so much that the computer simply didn't have time to call google.script.run and pass off the information from the client sided HTML window that it simply got closed and cut off when google.script.host.close was run. This means that the function will not exist in the execution transcripts or history, nor will there be any sort of runtime error. All of those things were true in my situation. This also explains why I never had the issue on any of my own equipment in a testing environment since it didn't suffer from any slowdowns the other computers were having.
By adding both Utilities.sleep(1000) and the UI alert this forces the javascript to not continue to google.script.host.close until the user interacts with the UI alert (Which is just a confirmation window with an OK button) and afterwards waits a full second. This sacrifices a tiny bit of user friendly-ness for a more functional script. Since I have implemented this "fix" none of my users are reporting any issues and all of my execution history looks just fine.
Hopefully this helps any future passerbys.
In the comments you posted this function snippet:
Here is a basic copy of the script that utilizes google.script.run:
function onFailure(error) {
MailApp.sendEmail("sparkycbass#gmail.com", "Order book eror", "ERROR: " + error.message);
google.script.host.close();
}
function handleFormSubmit(formObject) {
google.script.run.withFailureHandler(onFailure).processForm(formObject)
google.script.host.close();
}
The problem here is that google.script.run is asynchronous - the call to your server-side function processForm is not guaranteed to be even initiated before the call to google.script.host.close() is made:
Client-side calls to server-side functions are asynchronous: after the browser requests that the server run the function doSomething(), the browser continues immediately to the next line of code without waiting for a response. This means that server function calls may not execute in the order you expect. If you make two function calls at the same time, there is no way to know which function will run first; the result may differ each time you load the page. In this situation, success handlers and failure handlers help control the flow of your code.
A proper pattern is to only call "destructive" commands - such as closing the host and therefore unloading all the relevant Apps Script instances - after the server has indicated the async operation completed. This is within the success handler of the google.script.run call:
.html
function onFailure(error) { // server function threw an unhandled exception
google.script.run.sendMeAnEmail("Order book error", "ERROR: " + error.message);
console.log(error);
document.getElementById("some element id").textContent = "There was an error processing that form. Perhaps try again?"
}
function onSuccess(serverFunctionOutput, userObj) {
// do stuff with `serverFunctionOutput` and `userObj`
// ...
google.script.host.close();
}
function handleFormSubmit(formObject) {
google.script.run
.withFailureHandler(onFailure)
.withSuccessHandler(onSuccess)
.processForm(formObject);
}
.gs
function processForm(formData) {
console.log({message: "Processing form data", input: formData});
// ...
}
function sendMeAnEmail(subject, message) {
console.log({message: "There was a boo-boo", email: {message: message, subject: subject}});
MailApp.sendEmail("some email", subject, message);
}

Google Cloud Function: lazy loading not working

I deploy a google cloud function with lazy loading that loads data from google datastore. The last update time of my function is 7/25/18, 11:35 PM. It works well last week.
Normally, if the function is called less than about 30 minutes since last called. The function does not need to load data loaded from google datastore again. But I found that the lazy loading is not working since yesterday. Even the time between two function is less than 1 minute.
Does anyone meet the same problem? Thanks!
The Cloud Functions can fail due to several reasons such as uncaught exception and internal process crashes, therefore, it is required to check the logs files / HTTP responses error messages to verify the issue root cause and determine if the function is being restarted and generating Function execution timeouts that could explain why your function is not working.
I suggest you take a look on the Reporting Errors documentation that explains the process required to return a function error in order to validate the exact error message thrown by the service and return the error at the recommended way. Keep in mind that when the errors are returned correctly, then the function instance that returned the error is labelled as behaving normally, avoiding cold starts that leads higher latency issues, and making the function available to serve future requests if need be.

my nodejs script is not exiting on its own after successful execution

I have written a script to update my db table after reading data from db tables and solr. I am using asyn.waterfall module. The problem is that the script is not getting exited after successful completion of all operations. I have used db connection pool also thinking that may be creating the script to wait infinitly.
I want to put this script in crontab and if it will not exit properly it would be creating a hell lot of instances unnecessarily.
I just went through this issue.
The problem with just using process.exit() is that the program I am working on was creating handles, but never destroying them.
It was processing a directory and putting data into orientdb.
so some of the things that I have come to learn is that database connections need to be closed before getting rid of the reference. And that process.exit() does not solve all cases.
When my project processed 2,000 files. It would get down to about 500 left, and the extra handles would have filled up the available working memory. Which means it would not be able to continue. Therefore never reaching the process.exit at the end.
On the other hand, if you close the items that are requesting the app to stay open, you can solve the problem at its source.
The two "Undocumented Functions" that I was able to use, were
process._getActiveHandles();
process._getActiveRequests();
I am not sure what other functions will help with debugging these types of issues, but these ones were amazing.
They return an array, and you can determine a lot about what is going on in your process by using these methods.
You have to tell it when you're done, by calling
process.exit();
More specifically, you'll want to call this in the callback from async.waterfall() (the second argument to that function). At that point, all your asynchronous code has executed, and your script should be ready to exit.
EDIT: As pointed out by #Aaron below, this likely has to do with something like a database connection being active, and not allowing the node process to end.
You can use the node module why-is-node-running:
Run npm install -D why-is-node-running
Add import * as log from 'why-is-node-running'; in your code
When you expect your program to exit, add a log statement:
afterAll(async () => {
await app.close();
log();
})
This will print a list of open handles with a stacktrace to find out where they originated:
There are 5 handle(s) keeping the process running
# Timeout
/home/maf/dev/node_modules/why-is-node-running/example.js:6 - setInterval(function () {}, 1000)
/home/maf/dev/node_modules/why-is-node-running/example.js:10 - createServer()
# TCPSERVERWRAP
/home/maf/dev/node_modules/why-is-node-running/example.js:7 - server.listen(0)
/home/maf/dev/node_modules/why-is-node-running/example.js:10 - createServer()
We can quit the execution by using:
connection.destroy();
If you use Visual Studio code, you can attach to an already running Node script directly from it.
First, run the Debug: Attached to Node Process command:
When you invoke the command, VS Code will prompt you which Node.js process to attach to:
Your terminal should display this message:
Debugger listening on ws://127.0.0.1:9229/<...>
For help, see: https://nodejs.org/en/docs/inspector
Debugger attached.
Then, inside your debug console, you can use the code from The Lazy Coder’s answer:
process._getActiveHandles();
process._getActiveRequests();

$m->comp is returning infinite recursive call error

I am having trouble using HTML::Mason's $m->comp to redirect from one view to another.
There is a file say file1.mi which has embedded HTML code in this file1.mi I am using $m->comp to redirect to file2.mi.
But in the webpage whenever file1.mi is loaded it prints the footer multiple times and in the logs i am getting the errors
Nested page framework application dispatch detected, this usage is not
fully supported and may result in unexpected behavior
and
Error: APPLICATION CONTEXT ERROR (RENDER): 32 levels deep in component
stack (infinite recursive call?)
. Here is the script which i am using for redirecting from file1.mi
return $m->comp('/page-framework/dispatch.mi', applicationPath =>'/gp/tradein/omc', viewID => 'file2.mi', %ARGS);
I am using this script in file1.mi before it renders the webpage -- i.e. before any HTML scripts are executed.
I am kinda new to Mason, if you have queries regarding this please go ahead.
It looks like that your file1.mi gets loaded and rendered, then file2.mi gets executed and it in infinite loop.
Please, show us more code, it is not possible to debug with that small details.
What do you in the web server logs? Please, paste some example from loglines too.
Regards,
It should be your dispatcher dispatch.mi that is calling file1 or file2. Deciding that you want to go elsewhere after the request has already been dispatched seems like the logic is in the wrong place.