topic Re: February Developer Challenge - CAP Plugins: Week 2 in Application Development and Automation Discussions

February Developer Challenge - CAP Plugins: Week 2

thomas_jung — Tue, 05 Mar 2024 16:13:48 GMT

If you missed week 1, you can find all the details: here

Now that the challenge is complete: here is my sample solution: jung-thomas/dev-challenge-feb-2024: Developer Challenge February 2024 (github.com)

This week's challenge is going to build upon what we learned last week with the OData V2 plugin. We will continue working with the same project, but now we want to add support for GraphQL.

What is GraphQL?

GraphQL is a query language for APIs and a runtime for executing those queries by using a type system you define for your data. Unlike REST, which uses multiple URLs to access different resources, GraphQL accesses all the resources from a single endpoint with queries that articulate exactly what data is needed.

GraphQL and OData are both specifications for building and consuming APIs but take different approaches to some aspects.

GraphQL is a query language for APIs and a runtime for executing those queries by using a type system you define for your data.

OData defines a set of best practices for building and consuming RESTful APIs. It extends REST by providing a uniform way to describe both the data and the data model, enabling more detailed queries and interactions with the data.

How does this impact the SAP Cloud Application Programming Model?

The SAP Cloud Application Programming model was designed to be protocol agnostic as much as possible. While OData V4 is the default service type exposed by CAP applications; CAP was never intended to only support OData or just one version of that specification. Therefore its possible from a single model and service definition to support both OData and GraphQL even with the differences in approaches used by the two different protocols!

Your Task this week

Use the GraphQl Adapter plug-in to add GraphQL support to your project and to ONLY the CatalogService endpoint. And make sure that this same service also still supports OData V4 in parallel.

GraphQL Adapter: The GraphQL Adapter is a protocol adapter that generically generates a GraphQL schema for the models of an application and serves an endpoint that allows you to query your services using the GraphQL query language.

https://github.com/cap-js/graphql

To complete the challenge, post a screenshot from the graphql test tool (which can be accessed from /graphql url of your application) running a query against the ListOfBooks entity in the CatalogService.

Bonus 1: The test tool doesn't automatically include a link to the GraphQL test tool. But using a server.js file we can use the on serving event to extend the CAP test tool ourselves. Your bonus challenge is to add the code to your project to expose a link in the test tool to the GraphQL page but only for the service endpoints that support GraphQL. Hint: Several of the samples in the SAP-Samples repository on GitHub perform this technique.

Re: February Developer Challenge - CAP Plugins: Week 2

qmacro — Thu, 15 Feb 2024 10:36:35 GMT

For the bonus part:

Re: February Developer Challenge - CAP Plugins: Week 2

kumarniti4 — Thu, 15 Feb 2024 17:10:37 GMT

Screenshots:

Bonus:

Thanks, @qmacro, for the additional hint. I was so close already but gave up. I tried again after seeing your hint and found the example.

Re: February Developer Challenge - CAP Plugins: Week 2

ajmaradiaga — Wed, 14 Feb 2024 16:56:34 GMT

Adding GraphQL to service...

Re: February Developer Challenge - CAP Plugins: Week 2

satya-dev — Wed, 14 Feb 2024 17:52:10 GMT

I added and graphql adapter.

Re: February Developer Challenge - CAP Plugins: Week 2

egenoves — Wed, 14 Feb 2024 22:37:00 GMT

The GraphSql plugin:

Re: February Developer Challenge - CAP Plugins: Week 2

smok1 — Thu, 15 Feb 2024 04:59:45 GMT

Added GraphQL:

Bonus 1:

Re: February Developer Challenge - CAP Plugins: Week 2

Ruthiel — Thu, 15 Feb 2024 11:52:01 GMT

I tried to add the GraphQL link unsuccessfully.
Maybe something wrong with my server.js code.

Re: February Developer Challenge - CAP Plugins: Week 2

SandipAgarwalla — Thu, 15 Feb 2024 11:53:55 GMT

GraphQL query

Bonus - WIP

Re: February Developer Challenge - CAP Plugins: Week 2

stickman_0x00 — Thu, 15 Feb 2024 12:07:17 GMT

Felt more like I was learning how to search github than understanding how it works adding the links 😕

Re: February Developer Challenge - CAP Plugins: Week 2

thomas_jung — Thu, 15 Feb 2024 13:46:46 GMT

If you need a hint or help with the bonus feel free to direct message me here on the Community platform.

Re: February Developer Challenge - CAP Plugins: Week 2

Raghu_150 — Thu, 15 Feb 2024 13:56:46 GMT

Re: February Developer Challenge - CAP Plugins: Week 2

qmacro — Thu, 15 Feb 2024 14:34:43 GMT

Searching GitHub is a good skill to master! There's so much great material on CAP and everything there, that being able to pinpoint something or fish out an example of how to do something that the one that can wield search effectively has an advantage over those that can't. Plus you need to recognise and sift through CAP code examples to find the solution, so that's CAP specific! 🙂

Re: February Developer Challenge - CAP Plugins: Week 2

qmacro — Thu, 15 Feb 2024 14:40:39 GMT

If I may be so bold and offer a bit of a clue to those looking to complete the bonus part of this week's task. The search facility on GitHub is fantastic, and with the help of search modifiers, you can narrow in on what you're looking for with ease.

The base search is at https://github.com/search and the query language includes parameters that allow you to specific the context of your search. For example, you might want to set the `org` to `SAP-samples` and the `type` to `code`, and perhaps the `path` to something else, while looking for the things that @thomas_jung hinted at in the bonus description 🙂

You should end up with a very specific URL that you can GET in your browser, and there are (at the time of writing) only two results, both of which have code that you can use.

Good luck!

Re: February Developer Challenge - CAP Plugins: Week 2

stickman_0x00 — Thu, 15 Feb 2024 14:47:52 GMT

Can't argue with that and this time you guys did gave us enough tips to solve the problem 😋. In the mean time learned that how to do for the rest protocol too.

Continue keep bringing them!

Re: February Developer Challenge - CAP Plugins: Week 2

Former Member — Thu, 15 Feb 2024 18:10:40 GMT

graphql query:

bonus:

Re: February Developer Challenge - CAP Plugins: Week 2

smok1 — Thu, 15 Feb 2024 21:15:04 GMT

I just debug the 'standard code', understand how the 'standard Cap index' page is constructed and did my own solution. Curious to find the SAP sample solution on GIT.

Re: February Developer Challenge - CAP Plugins: Week 2

NagaPrakashT — Thu, 15 Feb 2024 22:34:01 GMT

Re: February Developer Challenge - CAP Plugins: Week 2

gustavo_paulo — Fri, 16 Feb 2024 01:20:46 GMT

GraphQL query

Bonus 1

Re: February Developer Challenge - CAP Plugins: Week 2

SandipAgarwalla — Fri, 16 Feb 2024 07:45:47 GMT

Can't seem to get the bonus execise correct. Found the server.js, but does not work 🙄