How could I get the Node specific ID in Node-Red? - node.js

I've already created a custom node, and I need to get the ID which displays on the INFO tab along with the type before the flow gets deployed.
So that I could use that ID as a unique id, to do CRUD operations.
How could I get this? Any help could be appreciated.

The data you want is available in the oneditsave call back function as follows:
...
oneditsave: function(){
var id = this.id;
...
}
As I said in the comment, you should only create resources to back a node at the point that the node is deployed as it may never be deployed and there is no way to clean up an undeployed node's resources.
The resources should be created in the javascript file so they can be cleaned up using the node.on('close',function(done){})

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files in server root not loading properly in Azure

I'm working on an app that instead of a database uses file system in the server's root directory. It's basically a note application that allows me to save notes. Each note is a serialized object of Note class represented by following structure \Data\Notes\MyUsername\Title.txt
When I'm testing this on localhost through IIS Express everything works fine and I can easily go step by step there.
However, once I publish the app to Azure, the folder structure is still there (made a test Controller that uses Directory.GetFiles() and .GetDirectories() to simulate folder browsing so I'm sure that the files are there) but the file simply doesn't get loaded.
Loading script that's being called:
public T Load<T>(string filePath) where T : new()
{
StreamReader reader = null;
try
{
reader = new StreamReader(filePath);
var RawDB = reader.ReadToEnd();
return JsonConvert.DeserializeObject<T>(RawDB);
}
catch
{
return default(T);
}
finally
{
if (reader != null)
reader.Dispose();
}
}
Since I can't normally debug the app on Azure I tried to dump as much info as I can through ViewData and even there, everything looks okay and the paths match, but the deserialized object is still null, and this is only when trying to open an existing note WITHOUT creating a new one first (more on that later)
Additionally, like I said, those new notes get saved in the folder structure, and there's a Note sidebar on the left that allows users to switch between notes. The note browser is nothing more but a list that's collected with a .GetFiles() of that folder.
On Azure, this works normally and if I were to delete one manually it'd be removed from the sidebar as well.
Now here's the kicker. On localhost, adding a note adds it to the sidebar and I can switch between them normally.
Adding a note on Azure makes all Views only display that new note regardless of which note I open and the new note does NOT get stored in the structure (I don't know where it ended up at all!) even though the path is defined at that point normally and it should save just like it does on localhost.
var model = new ViewNoteModel()
{
Note = Load<Note>($#"{NotePath}\{Title}.txt"), //Works on localhost, fails on Azure on many levels. Title is a URL param.
MyNotes = GetMyNotes() //works fine, reads right directory on local and Azure
};
To summarize:
Everything works fine on localhost, Important part doesn't work on Azure.
If new note is not created but an existing note is opened, Correct note gets loaded (based on URL Param) on Localhost, it breaks on Azure and loads default Note object (not null, just the default constructor data since it's required by JsonConvert)
If a new note is created, you'll see it on Localhost and you'll be able to open all other notes regardless, you will see only the new note on Azure regardless of note picked.
It's really strange and I have no idea what could cause this? I thought it had something to do with Azure requests being handled differently so maybe controller pushes the View before the model is initialized completely but that doesn't make sense since there's nothing async here.
However the fact that it loads a note that doesn't exist on the server it's even more apsurd and I have no explanation for that.
Additionally this issue is not linked with a session. I logged in through my phone and it showed the fake note there as well right away.
P.S. Before you say anything about storage, please note this. Our university grants us a very limited Azure subscription. Simple lowest tier App service and 5DTU SQL server and 99% of the rest is locked out of our subscription. This is why I'm storing stuff on the server, not because I believe it's the smart thing to do.

Feathers JS nested Routing or creating alternate services

The project I'm working on uses the feathers JS framework server side. Many of the services have hooks (or middleware) that make other calls and attach data before sending back to the client. If I have a new feature that needs to query a database but for a only few specific things I'm thinking I don't want to use the already built out "find" method for this database query as that "find" method has many other unneeded hooks and calls to other databases to get data I do not need for this new query on my feature.
My two solutions so far:
I could use the standard "find" query and just write if statements in all hooks that check for a specific string parameter that can be passed in on client side so these hooks are deactivated on this specific call but that seems tedious especially if I find this need for several other different services that have already been built out.
I initialize a second service below my main service so if my main service is:
app.use('/comments', new JHService(options));
right underneath I write:
app.use('/comments/allParticipants', new JHService(options));
And then attach a whole new set of hooks for that service. Basically it's a whole new service with the only relation to the origin in that the first part of it's name is 'comments' Since I'm new to feathers I'm not sure if that is a performant or optimal solution.
Is there a better solution then those options? or is option 1 or option 2 the most correct way to solve my current issue?
You can always wrap the population hooks into a conditional hook:
const hooks = require('feathers-hooks-common');
app.service('myservice').after({
create: hooks.iff(hook => hook.params.populate !== false, populateEntries)
});
Now population will only run if params.populate is not false.

Azure Mobile Service (node backend) __updatedAt property not automatically set after edit

After reading the documentation I was expecting that this field is automatically set by Azure Mobile Services. Apparently it isn't.
Should I configure something extra?
Other options that I see (to do for each table):
* add an axtra line to the node js update(item, user, request) function:
item.__updatedAt = new Date();
* create an update trigger in the database
Anybody experience with this?
Thx!
The __updatedAt column is updated by a trigger created in the underlying SQL Server database, so it should be updated any time a row is updated. Note that this requires a database operation to occur for it to be updated.

Uploading photos using Grails Services

I would like to ask, What would be the most suitable scope for my upload photo service in Grails ? I created this PhotoService in my Grails 2.3.4 web app, all it does is to get the request.getFile("myfile") and perform the necessary steps to save it on the hard drive whenever a user wants to upload an image. To illustrate what it looks like, I give a skeleton of these classes.
PhotoPageController {
def photoService
def upload(){
...
photoService.upload(request.getFile("myfile"))
...
}
}
PhotoService{
static scope="request"
def upload(def myFile){
...
// I do a bunch of task to save the photo
...
}
}
The code above isn't the exact code, I just wanted to show the flow. But my question is:
Question:
I couldn't find the exact definition of these different grails scopes, they have a one liner explanation but I couldn't figure out if request scope means for every request to the controller one bean is injected, or each time a request comes to upload action of the controller ?
Thoughts:
Basically since many users might upload at the same time, It's not a good idea to use singleton scope, so my options would be prototype or request I guess. So which one of them works well and also which one only gets created when the PhotoService is accessed only ?
I'm trying to minimize the number of services being injected into the application context and stays as long as the web app is alive, basically I want the service instance to die or get garbage collect at some point during the web app life time rather than hanging around in the memory while there is no use for it. I was thinking about making it session scope so when the user's session is terminated the service is cleaned up too, but in some cases a user might not want to upload any photo and the service gets created for no reason.
P.S: If I move the "def photoService" within the upload(), does that make it only get injected when the request to upload is invoked ? I assume that might throw exception because there would be a delay until Spring injects the service and then the ref to def photoService would be n
I figured out that Singleton scope would be fine since I'm not maintaining the state for each request/user. Only if the service is supposed to maintain state, then we can go ahead and use prototype or other suitable scopes. Using prototype is safer if you think the singleton might cause unexpected behavior but that is left to testing.

Microsoft Unity - How to register connectionstring as a parameter to repository constructor when it can vary by client?

I am relatively new to IoC containers so I apologize in advance for my ignorance.
My application is a asp.net 4.0 MVC app that uses the Entity Framework with a Repository layer on top of that. It is a multi tenant application so the connection string that is used varies by the logged in client.
The connection string is determined by a 'key' that gets passed in as part of the route which indicates the client. This route data is only present on the first request of the user's session.
The route looks kind of like this: http://{host}/login/dev/
where 'dev' indicates we are using the dev database.
Currently the IoC container is registering all dependencies in the global.asax Application_Start event handler and I have the 'key' hardcoded as follows:
var cnString = CommonServices.GetDBConnection("dev");
container.RegisterType<IRequestMgmtRecipientRepository, RequestMgmtRecipientRepository>(
new InjectionConstructor(cnString));
Is there a way with Unity to dynamically register the repository based on the logged in client using the route data that is supplied initially?
Note: I am not manually resolving the repositories. They are getting constructed by the container when the controllers get instantiated.
I am stumped.
Thanks!
Quick assumption, you can use the host to identify your tenant.
the following article has a slightly different approach http://www.agileatwork.com/bolt-on-multi-tenancy-in-asp-net-mvc-with-unity-and-nhibernate-part-ii-commingled-data/, its using NH, but it is usable.
based on the above this hacked code may work (not tried/complied the following, not much of a unity user, more of a windsor person :) )
Container.RegisterType<IRequestMgmtRecipientRepository, RequestMgmtRecipientRepository>(new InjectionFactory(c =>
{
//the following you can get via a static class
//HttpContext.Current.Request.Url.Host, if i remember correctly
var context = c.Resolve<HttpContextBase>();
var host = context.Request.Headers["Host"] ?? context.Request.Url.Host;
var connStr = CommonServices.GetDBConnection("dev_" + host); //assumed
return new RequestMgmtRecipientRepository(connStr);
}));
Scenario 2 (i do not think this was the case)
if the client identifies the Tenant (not the host, ie http: //host1), this suggests you would already need access to a database to access the client information? in this case the database which holds client information, will also need to have enough information to identify the tenant.
the issue with senario 2 will arise around anon uses, which tenant is being accessed.
assuming senario 2, then the InjectionFactory should still work.
hope this helps

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