I was just experimenting building a tiny app with Emberjs as my frontend framework.
All the app is, is a list which I can add names to with a textbox and button, then remove names from the list by clicking the delete button after each name.
I'm using a very simple Symfony2 application as my data store via a REST API and can currently add names to the list no problem. What I don't understand is how to go about deleting them.
If I add a new name to the list, it won't have the unique ID (my objects have an id and a name) that would be assigned by the DB engine, so when I come to delete it, I can't pass an ID to the DELETE API call.
How do I fix this? Do I need to somehow return the complete object (with ID) when calling the create API call and update the object (how would I do that with Ember?) or is there some other way of doing it?
Edit: Added an image better illustrating my question:
As already mentioned in the comments, when you create a new record the Store set's an internal id for the record, then when you commit to your backend your API should conveniently return the entire object back (with it's new id) ember will then take care to set the new server-side generated id back to your internally newly created record in the Store.
Your server should be serializing the id back to your ember app. If you're using Ember Data and your models are extensions of DS.Model, you don't have to define the id property on the model, but you can still use it.
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I need to store the values of devices' attributes with the right type in OrionCB's MongoDB.
As I was unable to perform that I dived into the code and found that IoTAgentUL (as well as IoTAgentJSON) uses OrionCB's API v1 instead of API v2.
As I can see API v1's updateContext sends data to MongoDB without it's type, so every measure is stored as text.
In the other hand I found that API v2's update entity send data to MongoDB with it's type. It produces that I can store attribute's values with it's type which benefits me when manipulating data (i.e. creating indexes, sorting, etc).
My question is if is there any workaround to solve this using the current implementations of IoT Agents.
The only workaround I can imagine is, once entities are automatically created by the IoT Agents, to update the type of such entities by your own. I mean, AFAIK, you can update both the value and the type of an entity.
In more details, I can think on a script that subscribes for all entities of certain type (those created by the agents). Then, when an entity is created this is notified to the script, which automatically updates the type of the entity's attributes.
Please observe you only need to modify the attribute's types once, just when the entities are created, not when an entity's attribute is updated; thus, something like an array or cache of already modified entities is needed in your script.
I have a following architectural question - my application back-end is written at Java and client side at AngularJS. Right now I need to store the user input on the page in order to be able to share and bookmark my application urls and restore the state by this url.
I'm going to implement the following approach - every time the user interacts with my application via selecting the data and conditions at the page I'll collect all of his input at a complex JSON document and store this document at Elasticsearch. Key of this document from ES I'll send back to client application(AngularJS) and based on this key I'll update the page url. For example the original url looks like:
http://example.com/some-page
based on a key from server I'll update this url to following:
http://example.com/some-page/analysis/234532453455
where 234532453455 is a key of a document in ES.
Every time the users will try to access the following url - http://example.com/some-page/analysis/234532453455 AngularJS application will try to get a saved state by key (234532453455) via Java backend REST endpoint.
Will it work ?
Also, I'm in doubt right now how to prevent the duplication of the documents in ES. Right now I have no experience with ES so don't know what approach from ES can be used out of the box for this purpose.
For example is it a good idea to calculate some hash code of each JSON document and store this hash code as a key of a document.. so before storing the new document I can check the old document by hash code. Also performance is very important to me so please take this into account also.
For me it sounds you try to implement cache.
Yes you can do this but if you will use ES only for this solution then I think you should better look to redis or memcached.
I can't say that ES is bad solution for this but ES has some tricks which you must remember for instance its near realtime search. After you index data they are not immediately available to search it takes few seconds depends on configuration(But you can also call _refresh but I am not sure about performance if you index data very often).
Hash: I dont see reasons to use has I'd better create right id. So if you have types of reports per user than id could be "reporttype_{userid}", because if you will use hash as an ID then each new object will have new id and instead of rewriting you will end up with having many copies of old data for that user. if you go with pattern reporttype_{userid} then each time when user regenerate report with new data you will just override it.
As an option you could add to that option fields userid and expireat for future cleanup, for instance you could have job which will cleanup expired reports, but this is valid only if you go with ES, since in redis and memcached there is option to set expiration when you save data
This is more of a question on design approach. I have an application which has the following details:
UI in Angular
UI uses an api which is in Node/Express
Database is just a JSON file for now.
I want to move to mongoDb from the JSON file. What I'd like is, whenever anyone uses the UI to make changes to the database, I'd like to review the changes before they are updated in the database. what is the best way to achieve this?
This was easier for me with the JSON file because I was creating a pull request on git where I would review all the changes and then update.
Things that I have thought:
Let the UI write to a separate clone collection(table) and then review them and update the main collection accordingly. Not sure if this is the right way to do it.
Are you yourself wanting to review changes, or wanting an end user to review before saving? If it's you, you have a few options:
You can create a mongodb collection of pending objects that will get moved to a different collection once they're approved. This is OK, but not great because you'll end up shuttling objects around and it's probably more reasonable to use a flag to do aggregate grouping instead of collection-based delineation
You can simply use a property on an object as a flag and send objects that are pending review to your db with that flag enabled (using some property like true, 1, or another way of saying "this is true/on/enabled etc.")
If you want an end-user to be able to save, you can use mongoose hooks/middleware to fire off validators or whatever you want and return a response with meaningful data back to your angular UI. From there, you can have a user 'review' what they're saving. This doesn't persist or get saved, it's only saved once they send everything back up again (if that's how you choose to build the save process).
I am developing a mobile app which retrieves data from a Liferay-based portal. I am using JSON web services to access the data which works well for e.g. Blog Entries. How can I make a new web service for existing tables? Each tutorial I have found starts with the definition of a new entity (i.e. database table), but I don't need that. I just want to access existing data in such a way which is not provided by system ws, e.g. to filter web content which have a specific structure.
Note: I tried also a workaround, I managed to make a struts action which prints out the desired JSON data and returns null. When I enter the address for the action in a browser, I see the JSON string. But if I put it in my mobile app, I see an HTML code, it seems that it is redirected to the home page of the portal.
Neat trick if you don't want to define a new entity with servicebuilder: Just leave the entity empty, this defines just a type, but no fields, e.g. no underlying table. Then implement your methods by just delegating to whatever persistence you'd like to access (or even without any persistence).
<Entity name="Foo" local-service="true" remote-service="true">
</Entity>
This will create FooServiceImpl and FooLocalServiceImpl that you can use to implement your business logic, without any attached database table.
We are currently trying to set up routes in such a way that the returned content-type can be set using a route parameter. The routing is all working properly now, but there is one problem. If one requests html, then the normal view script is rendered. The data we provide to this script can be anything from a string to a collection of objects, and the view script decides what to show to the user.
If however JSON response is requested, then we just provide the data returned from our controller as JSON. However, some data should not be made publicly available to the user, and hence some filtering is required. Is there any possibility to use JSON view scripts (as in ZF1 with context-switch) in order to support such filtering? Or maybe another method?
There is no such thing as a JSON script which lets you decide what to render and what not. You have to provide the proper data in the view model such that only the data is given that is eligible to be displayed.
I have been thinking about a hook in the JSON renderer so you can filter the view model's data based on the context of the request, but such thing does not exist yet. Unfortunately, you have to select the data in your controller or model.