topic SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category in Application Development and Automation Discussions

SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

qmacro — Wed, 16 Aug 2023 07:09:33 GMT

(Check out the SAP Developer Challenge - APIs blog post for everything you need to know about the challenge to which this task relates!)

You've made various read-only requests so far; now it's time to create some data.

Background

For this task we return briefly to the Northbreeze service from Task 2. Until now, mostly due to the nature of the deliberate simplicity of the tasks in this Developer Challenge, the actions you've been performing from an HTTP perspective have been read-only.

This time you'll write some data, albeit data that won't last long (the Northbreeze service runs in-memory and has been set up not to use a permanent persistence layer). Then you'll read it back, with a minor difference, to examine what the response looks like. It's that response, compressed, that you'll need for the hash.

The Northwind service traditionally has products, which you've encountered already. Those products are organized into categories, of which there are just a few. A category (taking the first one) looks like this:

{
  "CategoryID": 1,
  "CategoryName": "Beverages",
  "Description": "Soft drinks, coffees, teas, beers, and ales"
}

You can get a feel for the distribution of products across categories by asking for the count of products by category ID which is expressed like this (showing the path, with whitespace, for easier reading):

/odata/v4/northbreeze/Products
  ?$apply=groupby(
    (Category_CategoryID),
    aggregate($count as productcount)
  )

This returns a response that looks like this:

{
  "@odata.context": "$metadata#Products(Category_CategoryID,productcount)",
  "value": [
    {
      "productcount@odata.type": "#Decimal",
      "productcount": 12,
      "Category_CategoryID": 1,
      "@odata.id": null
    },
    {
      "productcount@odata.type": "#Decimal",
      "productcount": 12,
      "Category_CategoryID": 2,
      "@odata.id": null
    },
    {
      "productcount@odata.type": "#Decimal",
      "productcount": 13,
      "Category_CategoryID": 3,
      "@odata.id": null
    },
    {
      "productcount@odata.type": "#Decimal",
      "productcount": 10,
      "Category_CategoryID": 4,
      "@odata.id": null
    },
    {
      "productcount@odata.type": "#Decimal",
      "productcount": 7,
      "Category_CategoryID": 5,
      "@odata.id": null
    },
    {
      "productcount@odata.type": "#Decimal",
      "productcount": 6,
      "Category_CategoryID": 6,
      "@odata.id": null
    },
    {
      "productcount@odata.type": "#Decimal",
      "productcount": 5,
      "Category_CategoryID": 7,
      "@odata.id": null
    },
    {
      "productcount@odata.type": "#Decimal",
      "productcount": 12,
      "Category_CategoryID": 8,
      "@odata.id": null
    }
  ]}

As you can see, the OData V4 aggregate facilities, and CAP's support for them, is pretty neat!

Your task

Your task is to create a new category, and then request it. In other words, you must contruct an appropriate HTTP request to form an OData CREATE operation, to add a new category entity into the entity set. You can see from above that a category has just three properties:

CategoryID - this is the key and must be an integer value
CategoryName - a short name for the category
Description - a brief summary of what the category is

You must supply the following values for these properties when creating your new category:

CategoryID - your SAP Community ID number (see the Hints and tips section)
CategoryName - your SAP Community ID in lower case
Description - the static text August Developer Challenge

You can tell that the CategoryID property must be a number, because of how it's defined in the OData service's metadata document.

Once you've created your new category, you must then construct an appropriate HTTP request to form an OData READ operation to request a representation of your category. There are some important points here:

you must use an OData READ operation and not an OData QUERY operation
you must exclude the Description property, i.e. you should request (and expect) only the category properties CategoryID and CategoryName
the representation of the response must be in JSON

The representation of the response is the value you need to hash and share as a new reply to this discussion thread, as always, and as described in Task 0. Note that you'll have to URL encode the entire value, as you will be sending it within the value=('...') part of the hash service URL.

You should ensure that the order of the properties in the JSON object structure returned is sorted (it should already be, but double check or just add that processing to whatever mechanism you build to do this) and that there is no extraneous whitespace in the structure at all.

Here's an example of what a response representation will look like - note the single line and no whitespace, and that the CategoryName value is all lower case:

{"@odata.context":"some-context-specification","CategoryID":53,"CategoryName":"qmacro"}

Hints and tips

You already know about your SAP Community ID. For example, qmacro is the SAP Community ID for DJ Adams. To get your SAP Community ID number, which is unique, just go to your profile page, and get the number from your profile page's URL. For example, the profile page for DJ Adams is at https://groups.community.sap.com/t5/user/viewprofilepage/user-id/53 and looks like this:

You can see the SAP Community ID number in the URL - it's 53. Go to your profile page and get the number from the resulting URL for your profile.

What about the OData READ vs OData QUERY operation question? Both use the same HTTP method (GET) but the structure of the data returned is different. Given that the data and its structure is what you need to ensure is correct before hashing it, it's important you think about how you would request that single new category.

For discussion

What is the definition of the CategoryID property, according to the metadata document?

What is the difference between the result of an OData QUERY operation and the result of an OData READ operation? How does this relate to OData's origins? What is the significant difference in data structure returned?

Did you try to request a different representation of your category, such as XML? What happened?

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

harsh_itaverma — Wed, 16 Aug 2023 09:32:08 GMT

6444dddcbedf9d37b40eca030044c0df44e19f4ba2604de0acf15fbcff899fd4

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

harsh_itaverma — Wed, 16 Aug 2023 06:56:13 GMT

Not sure if this is correct, as I had to encode the JSON representation to get the hash value.
@qmacro are we supposed to do so?

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

qmacro — Wed, 16 Aug 2023 07:10:44 GMT

Speedy! 👟

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

qmacro — Wed, 16 Aug 2023 07:11:26 GMT

Well done - yes, you are correct. I've just added a note to the "Your task" section to help make this more explicit for others. Thanks for asking! 👍

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

vladimirs_semikins — Wed, 16 Aug 2023 07:41:29 GMT

bfb2201deadd6ffdf1914a0ed5f72ad1f5c3849800aabbfbe0f66707f23aa2f1

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

vladimirs_semikins — Wed, 16 Aug 2023 07:42:28 GMT

I've used ChatGTP to explain to me what is the difference between OData READ and QUERY

finger cross🤞that it explains me correctly 😄

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

ajmaradiaga — Wed, 16 Aug 2023 07:45:25 GMT

2c99f60839faf0bd532af31708fc0e05965fc240cf495373759e4bceeed9ae67

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

ajmaradiaga — Wed, 16 Aug 2023 07:51:38 GMT

I encode the whole response but I don't get the same value as @harsh_itaverma.

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

kasch-code — Wed, 16 Aug 2023 08:29:30 GMT

47831e26b73993b5f956540378c2f7e7b7fe286459078de9772f7abe2b2d3a08

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

harsh_itaverma — Wed, 16 Aug 2023 09:24:21 GMT

@ajmaradiaga you would find it funny but I checked my answers imitating yours and @vladimirs_semikins answer and was happy that it's matching 😛

My bad as I posted the wrong hash that I got with the JSON representation without removing the whitespaces.
Thanks a lot for the heads up.

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

harsh_itaverma — Wed, 16 Aug 2023 09:43:16 GMT

@ajmaradiaga can you please check once how you tried getting the hash for me cause looks like it was correct 😞

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

berserk — Wed, 16 Aug 2023 09:58:07 GMT

Thanks for the hint!

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

berserk — Wed, 16 Aug 2023 09:58:16 GMT

f8da703135004ae8b7f3111413e80a1b4551dfa9387c4dd70bdde358f917a1d1

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

SandipAgarwalla — Wed, 16 Aug 2023 10:27:45 GMT

722fba17bfeae45e6787a523f3b12ef69bd51d5fc4b34981de327dfb358ed17c

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

stickman_0x00 — Wed, 16 Aug 2023 10:36:30 GMT

de5b555ae1d367b049d7d96e4d9f97df8d1e1f8bf1eae50ad2742adfe722007d

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

nicoschoenteich — Wed, 16 Aug 2023 12:00:48 GMT

02a4b2a5a12b133de4ed00f94aff580283f8cab4211dcff0c18d5f5d87fcf02c

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

Tomas_Buryanek — Wed, 16 Aug 2023 12:07:39 GMT

7d66d8c69da53c9c2616a1a7cd40e4a3d0357f06552bdaf4de83965420f0456a

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

Tomas_Buryanek — Wed, 16 Aug 2023 12:36:21 GMT

This was fun!

Like some others, I also decided to ask Chat GPT for some help (OData operations, filters etc..) and was surprised by very helpful and on-point answers. In this sense "Googling" is much worse.

Then I just used REST client. In my case one of the browser extensions 🙂

Re: SAP Developer Challenge - APIs - Task 6 - Create a new Northbreeze category

qmacro — Wed, 16 Aug 2023 12:39:58 GMT

Great! That's one aspect of this challenge that I wanted to stay with - to have tasks that are fun. So that makes me happy that you had fun 🙂