I am using Breeze JS and would like to implement a server with full CRUD functionality using Progress Openedge. The Breeze website talks a lot about being able to write your own server implementation but I can find no information describing the format of a save bundle that Breeze sends to the server. Does anyone know of any documentation or schema?
The documentation for this is buried in the DataServiceAdapters page. Look about halfway down, under the heading saveChanges (saveContext, saveBundle) -> promise.
There's an example of what the JSON looks like in this SO answer.
The SaveBundle is not documented for a very good reason: it has no definition in BreezeJS!
It could be any serialized object that your server requires to satisfy yoursaveChanges work flow. You can see that this is true by examining the a60_abstractDataServiceAdapter.js source in github:
proto._prepareSaveBundle = function (/*saveContext, saveBundle*/) {
...
throw new Error("Need a concrete implementation of _prepareSaveBundle");
};
Breeze does ship with an implementation b00_breeze.dataService.webApi that satisfies the expectations of the companion Breeze ASP.NET Web API helper classes such as ContextProvider. This implementation is worth studying if you decide to write your own server support code.
But it is only one of many possible implementations. An OData web server, for example, requires an entirely different package and format for "$batch" change-set saves. Only you know what's right for your "Progress Openedge" server.
All that said, we do delve into some critical aspects of the SaveBundle destined for Breeze Web API services in the documentation for "ContextProvider".
Feel free to follow-up with more specific questions after you've read that.
Related
How can Breeze JS be used to consume a pure, simple, plain old RESTful API? Consider a web api endpoint that does not support OData and does not have Microsoft Entity Framework as the OR/M layer.
I see there's this Edmund's sample here, but I would like it to be more specific on how to manually setup BreezeJS metadata, since from what I understand about not having OData support is the fact that you lose out-of-the-box metadata resolution for the model consumed from an api endpoint. I quote from this Edmund example:
we have not yet described the Metadata Definition API properly. We ask that you rely on your intuition as you read this code ... your intuition will usually be correct. Please post questions to StackOveflow tagged with "breeze".
Is there any source of information on this topic that leaves intuition aside?
That Edmunds sample is so old, it pre-dates any of the documentation on how to write metadata.
Take a look at the Metadata by Hand topic in the BreezeJS documentation.
I'm looking for examples on how to implement a custom data provider for OData 4 and WebAPI (preferably for an in-memory untyped dataset).
Doese anyone know of any examples out there? My googeling turned up little of use.
I know of this example: http://msdn.microsoft.com/en-us/data/gg191846
But can't find the project-files for the example-code ... also it's from 2011 and things have changed since then...
You can refer to Web API OData Sample code at
https://aspnet.codeplex.com/SourceControl/latest
You can find the code at "Samples/WebApi/OData/v4/ODataUntypedSample" in the left panel.
There is another blog talking about "Typeless Entity Object Support in WebApi".
http://blogs.msdn.com/b/leohu/archive/2013/11/05/typeless-entity-object-support-in-webapi.aspx
Im new to breeze js, I understand that breeze has it's own query language related to OData
But I am trying to get breeze js working with a custom query language, as an example FIQL is
one of the form to make queries to backend, can we get breeze run with this type of query language.
Overview of FIQL :-
http://jaxenter.com/tutorial-smarter-search-with-fiql-and-apache-cxf-46876.html
(this is not a technical answer, at the very most it's an advice)
As mentionned from their website documentation :
Today, out of the box, the Breeze product ships with adapters for the
ASP.NET Web API and for OData. It also ships with .NET components that
interface with the Entity Framework and that generate Breeze metadata
from an Entity Framework model; that EF model could be developed code
first or database first. The Breeze client is in no way limited to
these technologies; they are merely the first backend components
available; we’d be thrilled to help you adapt Breeze to your preferred
server stack.
First question is whether
1) you want breeze to actually create FICL queries on the client and send them to a FICL service. This involves translating a client side breeze EntityQuery into FICL url syntax. If so you would need to create a new a 'uriBuilder' adapter.
2) you want to translate a breeze query already sent to your service into FIQL syntax on the server so that you can further refine the query and then send it on to your FICL service. If so you would need to create a breeze DataService endpoint.
Both of these are certainly possible.
If you are looking at the 1st option, take a look at the 'b000_uriBuilder.xxx' files in the breeze GitHub repo under the 'src' directory. There should be two 'uriBuilder.xxx' files, one which translates an EntityQuery into OData syntax and another that translates the EntityQuery into a new 'json' query syntax. There is also additional information on this 2nd syntax here:
http://www.getbreezenow.com/documentation/query-using-json
Both of these 'uriBuilder's make use an internal 'visitor' framework that we have not yet documented but should be reasonably understandable by looking at the source.
If you are looking at the 2nd option, I would recommend looking at the link mentioned above and then taking a look at the 'breeze.node.js' repo and the 'breeze-sequelize' subdir within it. In this repo we take a serialized server side breeze EntityQuery and translate it into a 'Node' Sequelize query that we can apply to a variety of backends.
Another option is to contact our professional services arm, at breeze#ideablade.com and ask them to assist in building the adapters for you or to ask for more detailed technical help.
I'm looking for a starting point on how to extend BreezeJS (or if it's even possible!) to support sending JSON data using the Badgerfish notation to the server from BreezeJS.
I see that BreezeJS has the JsonResultsAdapter - to take a response from the server and transform it - which would work to allow Breeze to walk through a Badgerfish JSON result set and instantiate entities.
I need the other way - a JsonRequestAdapter (or something like it) - to take the JSON that Breeze has created and about to send to the server, and modify to the Badgerfish notation.
Any guidance for this problem? thanks!
Update: June 2013
I've gone with the approach of implementing a custom Breeze DataService adapter that I pass into an EntityManager instance. This approach is not for the faint of heart to be honest, and took some work to really understand what needed to happen. I took the provided Web API DataService adapter and 'adapted' it to work for a generic RESTful service.
Adam, this is a great question.
We are trying to come up with a standard mechanism analagous to the 'JsonResultsAdapter' to be used to intecept http 'puts' but really want to understand the most common use cases first. We'd love any feedback on suggestions and use cases.
Please add a 'feature request' for this to the Breeze User Voice. We take these suggestions very seriously and this is a topic that we think is important as well, but really want to get some feedback from our community on its priority.
Here is my knowing about ASP.NET SPA:
have to use Upshot to talk to the server;
have to use DbDataController to provide Web APIs;
have to use Entity Framework Code first...
so, many concerns come out:
have to provide metadata for the upshot to work, this will obviously expose the structure of your database;
can i use Entity Framework Database First instead of Code First? You may ask why. Because Code First don't provide you the ability to customize your database(index customization, stored procedure...etc.);
A problem i met: when i add a "TestUpshot.edmx" file(generated from database 'northwind') to the MySpaApp.Models folder(trying to test whether i can use the edmx classes in the MyDbDataController class, and generate proper metadata in the client side), and run the application, there is an exception:"System.ArgumentException: Could not find the conceptual model type for MySpaApp.Models.Categories."...
Need help here, thanks in advance.
Dean
I may be missing something, but there is no requirement to use any of the technologies you've listed.
An SPA is just a pattern. You can use whatever you need to achieve that. There may be benefits with choosing certain technologies, ie templates, tutorials, etc.
Doesn't really answer your question, but should lead you to experiment with what you've got.
SPA is actually a way to conceptualize your client application. SPA comes the closest to the fat client - data server concept from the current web approaches. Definitely this will be the ruling concept within a couple of years.
Your concerns can be addressed using JayData at http://jaydata.codeplex.com that provides advanced, high level data access for JavaScript against any kind of EntityFramework back-ends (db, model or code first). Check out this video that presents the whole cycle from importing your EDMX from SQL (this could eighter be model first definition as well) to inserting a new product item in the Products table from JavaScript.