Everything in CAP / Node.js
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Error handlingSAP and community
Beginners Guide to Advanced Event MeshBeginners Guide to Advanced Event MeshA scenario-by-scenario walkthrough of Advanced Event Mesh, run through Cloud Integration iFlows: publishing and consuming queue messages, dead message queue setup with retry counts and acknowledgment modes, direct messages, durable topic endpoints and selectors, time-to-live, REST Delivery Points, replay by replication group message ID, parallel consumers with partition keys, and the request-reply pattern. Each scenario is built and verified step by step against a Solace trial account standing in for AEM.PriyankaChak, published 2025-07-24
Don't "let it crash", is this the new CAP guideline?Don't "let it crash", is this the new CAP guideline?Dinu traces a change in error handling in CAP's Node.js runtime: @sap/cds@8.2.0 adds a cds.server.shutdown_on_uncaught_errors config flag, defaulting to true, but invoking an operation with an undefined variable no longer takes the server down, with or without the flag, where the same code crashed it on cds@6 and cds@7, and the author notes the old behaviour was already missing in cds@8.1. It still crashes with features.odata_new_adapter turned off to use the old OData parser, so it is the new OData adapter, like the REST adapter before it, that answers an uncaught error with a 500 instead of taking the process down.Dinu, published 2024-09-06
Effective Axios Error Logging for Robust SAP IntegrationsEffective Axios Error Logging for Robust SAP IntegrationsTwo logged failures printed side by side, and the point is made by looking at them: one tells you what went wrong and one does not. Axios buries the useful part of an HTTP error, and this is what to unwrap before logging it from a CAP service.Sahil2508, published 2025-08-31
Messaging System for Transferring Error, Warning, and Information Messages from OData V4 Services to HTTP Client ApplicationsMessaging System for Transferring Error, Warning, and Information Messages from OData V4 Services to HTTP Client ApplicationsGetting a message out of a CAP service and onto a Fiori elements object page in a draft scenario — errors, warnings and information, each of which the UI treats differently. Co-written with one of the people on the OData side, and it spends its length on the message container rather than on the handler that fills it.arley-triana-morin, published 2022-08-11
Messaging System for Transferring Error, Warning, and Information Messages from OData V4 Services to HTTP Client Applications
OData changed in @cap-js-community/odata-v2-adapter 1.10.0, 2023-04-05. Affects A recipe, Runnable code.
SAP Cloud Application Programming Model（CAP）：カスタムロジックの実装 – Part 2SAP Cloud Application Programming Model（CAP）：カスタムロジックの実装 – Part 2A walkthrough of implementing custom logic in a CAP Node.js service for the capire bookshop sample, registering before, on and after handlers around the generated CRUD service for its Books and Orders entities. The before handler validates an incoming order's amount and runs a transactional CQN UPDATE to decrement stock, raising a 400 or 409 through req.error when the amount is invalid or no rows match; an after handler on READ appends a discount note to overstocked books.rasai, published 2021-01-01
GraphQLSAP only
CAP: GraphQL as new protocolCAP: GraphQL as new protocolWritten days after @cap-js/graphql appeared, by somebody who went looking for it — an introduction to GraphQL alongside what the adapter actually does to a CAP service. The first outside account of the capability, and still one of very few.jhodel18, published 2023-03-18
CAP: GraphQL as new protocol
@cap-js/graphql has been through 11 major lines since this was published, most recently 0.12 (2025-05), 0.13 (2025-07), 0.14 (2025-10). Affects Runnable code.
SAP CAP function and action with Unstructured/Dynamic Type Input/OutputSAP CAP function and action with Unstructured/Dynamic Type Input/OutputA CAP action or function can take or return an unstructured type: annotate the service @protocol: 'rest', declare the parameter or return value as @open type object {}, and a handler shapes the payload however a given request needs, shown here with a bound action and a function that returns a different structure per input. The text states plainly that OData V4 and GraphQL services require a fixed structure for action and function parameters, so the dynamic type works only over CAP's REST protocol.published 2022-12-08
SAP CAPv7 - Node.js Highlights and ExperiencesSAP CAPv7 - Node.js Highlights and ExperiencesAn account of upgrading a 100+ table CAP Node.js project from v6 to v7, working through breaking changes in @sap/cds 7: event handlers now always receive an array, service paths move under /odata/v4/... unless serve_on_root is set, and cds-serve replaces cds run. It goes deepest on the GraphQL plugin, @cap-js/graphql: the /graphql endpoint it serves, Composition results wrapped in a nodes connection, and offset-based pagination reached through OData's top and skip rather than GraphQL's own limit and offset.published 2023-08-03
SAP GraphQL in CAPm (node.js)SAP GraphQL in CAPm (node.js)Adding the GraphQL protocol adapter to a CAP project when it was new — an entity, some data, the feature switched on, and a check that it answers. Short, and it is the earliest account here of CAP speaking something other than OData.enric101, published 2021-11-29
Metadata publishingSAP and community
CAP, CDS, CDL, CSN and jq - finding associationsCAP, CDS, CDL, CSN and jq - finding associationsHow associations are actually represented once CDL is compiled into CSN, worked out by parsing the machine-readable form with jq. Useful less as a recipe than as a way in: anything that wants to reason about a CDS model without the compiler has to read CSN, and this is what that looks like from the outside.published 2024-04-16
Develop a full stack Business application with SAP Cloud Application Programming ModelDevelop a full stack Business application with SAP Cloud Application Programming ModelBuilds a full-stack CAP application in SAP Web IDE Full Stack's now-retired 'SAP Cloud Platform Business Application' template: a data-model.cds entity with its own service definition, then Fiori annotations on the generated OData. Building the project compiles that model into Catalog.xml and csn.json, the EDMX and CSN that metadata publishing says every exposed service gets. The entity and service definitions it writes by hand are the basic shape data modelling covers, though the webIDE and MTA tooling staged around them is gone.former_member584731, published 2018-11-29
Importing an external data model using CDS Graphical Modeler for Visual Studio CodeImporting an external data model using CDS Graphical Modeler for Visual Studio CodeWalks through the CDS Graphical Modeler for Visual Studio Code: creating a "Customers" entity, importing an external OData model from an edmx file into the CDS model, and drawing a managed association from the new entity to an entity from the imported namespace. The import happens through the modeler's GUI rather than the cds import command, and the imported edmx becomes a CDS file the modeler can open directly.Xiao-fei_Song, published 2022-05-09
Importing external edmx files to your CAP project using the CDS Graphical ModelerImporting external edmx files to your CAP project using the CDS Graphical ModelerAn EDMX downloaded from the API hub — API_BUSINESS_PARTNER in the example — imported into the CDS model and its entities exposed as projections, done through the graphical modeller rather than cds import. Barely a page long.Xiao-fei_Song, published 2021-05-19
Introducing the Cloud Application Programming Model (CAP)Introducing the Cloud Application Programming Model (CAP)SAP's own general-availability announcement for CAP, laid out as a Golden Path: a data model and service defined in CDS gets a generated service provider that serves metadata publishing and CRUD requests, fills in primary keys and audit data, and writes trace and audit logs without application code. The same CDS model carries annotations that translate to OData vocabularies and generate a Fiori elements app skeleton, which is how Fiori annotations work in CAP.Daniel7, published 2018-06-05
SAP Cloud Platform Backend service: Tutorial [12]: CDS : local: buildSAP Cloud Platform Backend service: Tutorial [12]: CDS : local: buildCompiling a CDS model locally with the cds command-line tool, installed from @sap/cds via SAP's own npm registry, before uploading it to SAP Cloud Platform Backend service: cds compile converts the model to CSN by default, --to edmx or --to edm produces the OData V2 or V4 metadata document, and --to hana or --to sql produces the database-specific definition files. It shows the local build catching an error the CDS editor's own validation misses — an entity with no key, valid CSN but invalid OData — before the same model reaches the server's compiler.CarlosRoggan, published 2019-04-15
ODataSAP and community
ui5-call-actionui5-call-actionFour UI5 apps over one CAP service, each calling the same bound, collection-bound and unbound OData actions and functions from custom code.independent, cap
UI5 apps calling CAP OData actions and functions from custom code
Neither the package manifest nor the repository tree declares a licence.
#BTP #SAPCAP: Quirky Nuggets (N03-N04)#BTP #SAPCAP: Quirky Nuggets (N03-N04)Two unrelated findings in one post, which is the format of the series: the OData operators tried against a CAP service — with a schema of deliberately awkward types to try them on — and undeploying database artifacts, which is the half people hit in anger. Numbered N03 and N04 of a run that continues either side.Ajit_K_Panda, published 2023-06-05
#BTP #SAPCAP: Quirky Nuggets (N03-N04)
Deployment changed in @sap/cds-dk 8.9.0, 2025-03-31. Affects A recipe, Runnable code.
AI-assisted full stack development using model context protocol serversAI-assisted full stack development using model context protocol serversMCP servers in Visual Studio Code used to configure, query and change a full-stack application built with CAP, CDS and OData: the agent access to your code concern, a coding assistant reading and changing the project it works in. The abstract names no server, so neither @cap-js/mcp-server nor any other is attached, and it does not say which changes are made. A TechEd 2026 session (Thursday 29 October, Berlin), presented by Sergio Guerrero, written here from SAP's abstract; the recording is not yet published.
Calling bound / unbound CAP actions from Fiori elements application.Calling bound / unbound CAP actions from Fiori elements application.invokeAction from the Fiori elements Edit flow API, with the difference between bound and unbound actions spelled out first because the call shape differs. Under three thousand characters and it answers exactly one question.vidhyasagarmule, published 2024-09-07
Consume Remote Services in a Full-Stack CAP ApplicationConsume Remote Services in a Full-Stack CAP ApplicationExtending the Developer's Guide application with a remote S/4HANA service — connectivity, importing the Business Partner API, and running against it. SAP publishes this as four separate paths: mock server or real S/4HANA Cloud, times Cloud Foundry or Kyma. One entry covers all four, because the difference between them is which backend and which runtime, not what you learn.SAP
Create a Business Service using CDS, Node.js, SQLite and a OData serviceCreate a Business Service using CDS, Node.js, SQLite and a OData serviceThe stack at its smallest — CDS, Node, SQLite, an OData service — worked through at length. Nothing cloud in it, which is the point: it is the shape of a CAP service before any of the platform arrives.raybanton, published 2021-07-12
Create a Business Service using CDS, Node.js, SQLite and a OData service
Database connectors has changed twice since this was published, most recently in @sap/cds 10.1.0, 2026-09-07. Affects A recipe, Runnable code.
Create CDS Views and expose through OData service in CAPMCreate CDS Views and expose through OData service in CAPMViews defined in CDS and then exposed, which is the whole of what a small CAP service is. Written step by step from cds init onward in Business Application Studio.VenkateshMundru, published 2025-08-11
Custom Functions in OData V4 – SAP Cloud Application Programming ModelCustom Functions in OData V4 – SAP Cloud Application Programming ModelFunctions rather than actions, and the distinction is where it starts: a function must return data and must never change any, so it is the read-only half of custom operations. Then how to declare and implement one on a CAP service.Roopa_N, published 2021-04-28
Custom Functions in OData V4 – SAP Cloud Application Programming Model
OData changed in @cap-js-community/odata-v2-adapter 1.10.0, 2023-04-05. Affects A recipe.
Extend SAP SuccessFactors on SAP BTP with CAP - Create the CAP ServiceExtend SAP SuccessFactors on SAP BTP with CAP - Create the CAP ServiceWalks through writing a service definition in SAP Business Application Studio that projects entities from an existing CDS model: one entity gets @odata.draft.enabled because Fiori Elements only shows CRUD actions on a draft-enabled entity, and a read-only projection of an already-imported SuccessFactors OData entity fails with the generic handlers because the call is delegated to the remote service, so a custom handler is needed. Running cds watch then serves the entities, drafts and $metadata at the declared service path.published 2022-03-23
Extend SAP SuccessFactors on SAP BTP with the SAP Cloud Application Programming ModelExtend SAP SuccessFactors on SAP BTP with the SAP Cloud Application Programming ModelTwelve tutorials, about two hours, building a side-by-side extension of SuccessFactors on BTP. The spine is remote services: importing the SuccessFactors OData service definitions into a CAP model, then treating them as entities the extension reads and writes through, rather than as an API called from a handler. Indexed as one entry because the parts only make sense in order.SAP
How to add OData v2 adapter proxy to your CAP projectHow to add OData v2 adapter proxy to your CAP projectThe problem is stated in one line — a UI5 application that only speaks OData v2 in front of a CAP service that speaks v4 — and the answer is a proxy in the middle rather than a rewrite of either end. Written while v4 support in the UI5 stack was still patchy, which is the whole reason the adapter exists.published 2020-06-30
How to add OData v2 adapter proxy to your CAP project
OData changed in @cap-js-community/odata-v2-adapter 1.10.0, 2023-04-05. Affects Runnable code.
How to Perform Initial Loads from S/4HANA to Advanced Event Mesh with Odata PollHow to Perform Initial Loads from S/4HANA to Advanced Event Mesh with Odata PollWalks through building a Cloud Integration flow that polls the S/4HANA Business Partner OData API on a timer, splits the response into individual records, and publishes each as an event to Advanced Event Mesh through its adapter, with the topic set dynamically from a grouping property. Selects fields and expands associations with $select/$expand against an EDMX from the API Business Hub, and works around the OData V2 adapter's lack of JSON support by falling back to the HTTP adapter with an XML-to-JSON converter. Flags the trade-off: the pattern needs no backend change beyond activating the API, but the polled payload has to stay aligned with whatever event format the ERP pushes on change.AlexPfeil, published 2025-04-04
Messaging System for Transferring Error, Warning, and Information Messages from OData V4 Services to HTTP Client ApplicationsMessaging System for Transferring Error, Warning, and Information Messages from OData V4 Services to HTTP Client ApplicationsGetting a message out of a CAP service and onto a Fiori elements object page in a draft scenario — errors, warnings and information, each of which the UI treats differently. Co-written with one of the people on the OData side, and it spends its length on the message container rather than on the handler that fills it.arley-triana-morin, published 2022-08-11
Messaging System for Transferring Error, Warning, and Information Messages from OData V4 Services to HTTP Client Applications
OData changed in @cap-js-community/odata-v2-adapter 1.10.0, 2023-04-05. Affects A recipe, Runnable code.
Resolving date serialization issues when using an external OData v2 service with CAPResolving date serialization issues when using an external OData v2 service with CAPDates coming out of an external OData v2 service in a shape CAP does not expect, and what to do about it. A narrow bug report with a fix, and the kind of thing that costs an afternoon if nobody has written it down.pieterjanssens, published 2020-07-09
SAP BTP SDK for iOS & CAP with OData V4 supportSAP BTP SDK for iOS & CAP with OData V4 supportThe iOS SDK gaining OData V4, which until then made connecting a native app to a CAP service awkward — CAP defaults to v4 and the SDK did not speak it. Short, and it marks the date that stopped being a problem.KRiedelsheimer, published 2021-04-21
SAP CAP Adapter to expose OData as custom REST ServiceSAP CAP Adapter to expose OData as custom REST ServiceWalks through consuming an external OData V2 service in a CAP project — cds import converts the Northwind service's EDMX into a CSN and cds.connect.to wires up the remote proxy — then re-exposing it as plain REST with the @protocol:'rest' annotation instead of OData's own envelope. Shows two ways to reshape the response, renaming and dropping fields in a CDS projection or rewriting the returned objects in a custom service handler, and remaps ?pageSize and ?offset onto OData's $top and $skip in that same handler.Former Member, published 2021-09-15
SAP CAP function and action with Unstructured/Dynamic Type Input/OutputSAP CAP function and action with Unstructured/Dynamic Type Input/OutputA CAP action or function can take or return an unstructured type: annotate the service @protocol: 'rest', declare the parameter or return value as @open type object {}, and a handler shapes the payload however a given request needs, shown here with a bound action and a function that returns a different structure per input. The text states plainly that OData V4 and GraphQL services require a fixed structure for action and function parameters, so the dynamic type works only over CAP's REST protocol.published 2022-12-08
SAP CAP(Cloud Application Programming)开发框架概述SAP CAP(Cloud Application Programming)开发框架概述A Chinese-language walkthrough of CAP built mainly from CAPire's own "About CAP" page: CDS entities, associations, compositions and aspects for data modelling, with an extend Books with @restrict: [{ grant:'WRITE', to:'admin' }] aspect as its authorization example; CQL and CQN queries shown against both a local service and OData's $select/$expand; and the service-and-event model — this.on, this.emit, srv.on — that carries CAP's async processing. It closes with the author's own setup: installing @sap/cds-dk, scaffolding a bookshop project with cds init, and running it with cds watch against local SQLite, mocked authentication and file-based messaging standing in for HANA Cloud, IAS and Kafka.ArthurYang, published 2024-01-07
SAP Cloud Application Programming Model: Deep Insert (4) Consume Remote ServiceSAP Cloud Application Programming Model: Deep Insert (4) Consume Remote ServiceFourth in a long series on deep insert, and the one where the target stops being local. Twenty thousand characters, project files linked, and the earlier parts on UUIDs and multi-level structures are prerequisites the author names.CarlosRoggan, published 2019-07-24
SAP Cloud Application Programming Model: Deep Insert (4) Consume Remote Service
Destinations changed in @sap-cloud-sdk/connectivity 4.0.0, 2025-03-04. Affects A recipe, Runnable code.
SAP Cloud Application Programming Model: Deep Insert (5) Consume Remote Service with SAP Cloud SDKSAP Cloud Application Programming Model: Deep Insert (5) Consume Remote Service with SAP Cloud SDKThe same thing again through SAP Cloud SDK, published as a deliberate comparison with the part before it — the author says outright that it does what the previous post did, differently. Reading both is how you see what the SDK is actually doing for you.CarlosRoggan, published 2019-07-26
SAP Cloud Application Programming Model: Deep Insert (5) Consume Remote Service with SAP Cloud SDK
Destinations changed in @sap-cloud-sdk/connectivity 4.0.0, 2025-03-04. Affects Runnable code.
SAP Cloud Platform Backend service: Tutorial [11]: CDS : magic: key: generationSAP Cloud Platform Backend service: Tutorial [11]: CDS : magic: key: generationExplains CDS's UUID key type: giving a key property UUID gets its value generated automatically instead of a hand-picked unused number, as data modelling lets an element's type do, at the cost of a 36-character value unfit for a user-facing display. It then works out how that generated value is addressed in a single-entity read URL — bare brackets in OData V4 against the guid'...' literal V2 requires — citing the OData specification for the difference.CarlosRoggan, published 2019-03-15
The Complete Guide to Calling Actions in UI5 with Custom CodeThe Complete Guide to Calling Actions in UI5 with Custom CodeWritten because the documentation is thin and the samples sparse, and openly as a note to the author's future self — hand-coding an action call has become a rare task for anyone mostly working in Fiori elements, which is exactly why it is hard to look up when it comes round. Comes with a CAP sample project, so the service half is there too.published 2025-07-21
The End2End Journey: Advocates Service – CAP Service, OData V2/4 & REST in One single ProjectThe End2End Journey: Advocates Service – CAP Service, OData V2/4 & REST in One single ProjectOne CAP service exposing OData V2, OData V4 and REST at the same time, which is unusual enough to be worth the read on its own. Part of an end-to-end series, deployed on Cloud Foundry against HANA Cloud, so the protocol question sits inside a whole application rather than a snippet.KRiedelsheimer, published 2021-05-06
The End2End Journey: Advocates Service – CAP Service, OData V2/4 & REST in One single Project
OData changed in @cap-js-community/odata-v2-adapter 1.10.0, 2023-04-05. Affects A recipe, Runnable code.
OpenAPISAP and community
Adding a Swagger UI to Your SAP Cloud Application Programming Model / Node.js ServiceAdding a Swagger UI to Your SAP Cloud Application Programming Model / Node.js ServiceThe problem stated from the other side of the wire: a CAP and HANA backend consumed by frontend developers with no SAP background, who said in the first meeting that they could not work from what the service offered. A browsable API page is the answer, and this is the post the Swagger UI plugin indexed here exists to serve.published 2020-01-23
Adding a Swagger UI to Your SAP Cloud Application Programming Model / Node.js Service
cds-swagger-ui-express has been through 11 major lines since this was published, most recently 0.9 (2024-07), 0.10 (2024-10), 0.11 (2026-02). Affects Runnable code.
Edge Integration Cell : Design, deploy and manage APIsEdge Integration Cell : Design, deploy and manage APIsWalks through creating an API artifact in API Management on the customer-managed Edge Integration Cell runtime, including the option to generate the artifact by importing an OpenAPI specification rather than from a URL or by hand. It then attaches an Authentication policy and a Quota step capped at four calls per minute, deploys, and shows both the resulting 401 and the quota-breach error in the Monitor logs. The author frames it as the first of a series on Edge Integration Cell's policies.published 2023-11-15
Invoke OpenAPI-documented APIs remotely with SAP Cloud Application Programming ModelInvoke OpenAPI-documented APIs remotely with SAP Cloud Application Programming ModelThe other direction: consuming an API described by an OpenAPI document from CAP, rather than publishing one. Worth pairing with the plugin entries here, which all serve the outbound half.wittro, published 2022-08-30
Invoke OpenAPI-documented APIs remotely with SAP Cloud Application Programming Model
Destinations changed in @sap-cloud-sdk/connectivity 4.0.0, 2025-03-04. Affects Runnable code.
Part 2 – Empowering SAP BTP CAP Services through Open API Spec and Annotations for Effective Communication, Collaboration and GovernancePart 2 – Empowering SAP BTP CAP Services through Open API Spec and Annotations for Effective Communication, Collaboration and GovernanceWalks through generating an OpenAPI specification for a Node.js CAP service: installing cds-swagger-ui-express, bootstrapping it in server.js, a sample CDS data model with associations and compositions, and the YUML diagram and endpoint details the Open API Preview renders in Business Application Studio. Also shows gating the Swagger UI behind a user-defined environment variable so it is served in development and QA subaccounts but excluded from the production deployment on Cloud Foundry. Second of a three-part series; the first covers the concepts and the third goes deeper into annotations.mohit_bansal3, published 2023-05-24
Swagger UI | SAP BTP Extension Generators | Hands-on Video TutorialsSwagger UI | SAP BTP Extension Generators | Hands-on Video TutorialsA blog post wrapped around a video playlist from the SAP HANA Academy — Swagger UI for CDS, added to the BTP extension generator series. The written half is an ingredients list and a table of contents; the substance is in the recordings.dvankempen, published 2021-07-09
Pagination and streamingSAP only
[Part – 2] Enrich CAP based Services with Behaviors using Annotations[Part – 2] Enrich CAP based Services with Behaviors using AnnotationsThe second half of a two-part walkthrough of CAP's behavioral annotations, following on from access control and input validation in the first part. This post works through @cds.autoexpose, @cds.api.ignore, @cds.persistence.exists/skip, @cds.on.insert/@cds.on.update and the @odata.Type/@odata.singleton mapping overrides, all shaping how a CDS model is projected into a service, which is data modelling. Alongside these it covers @cds.query.limit for default and maximum page sizes (pagination and streaming), @odata.etag with exclusive and shared locks for optimistic concurrency (concurrency control), and @cds.search for scoping $search to chosen elements (search), each with a CDS code example.published 2023-01-29
Serve your application over MCPSAP and community
API ManagementAPI ManagementAPI proxies in front of backend services, with security and traffic management policies attached to them, and Developer Hub where consumers subscribe.sap official, btp
API proxies with security and traffic policies and Developer Hub
Agentic CAP: Build MCP servers and enterprise AI agentsAgentic CAP: Build MCP servers and enterprise AI agentsCAP applications become AI agents over the Model Context Protocol and the Agent2Agent protocol, which is the serve your application over MCP concern, and SAP AI Core is the LLM integration through which AI is embedded in a CAP app, with recommendations from the SAP-RPT-1 model as the abstract's example. The abstract names the two protocols and the one model and does not say which packages carry them. A two-hour TechEd 2026 session in a hands-on room (Tuesday 27 October, Berlin), presented by Daniel Hutzel, Daniel Schlachter, Marc Huber and Sami Lechner, written here from SAP's abstract; the recording is not yet published.
CAP Node.js Expert Session #6 - The MCP AdapterCAP Node.js Expert Session #6 - The MCP AdapterDaniel Schlachter and DJ Adams add @cap-js/mcp to a bookshop service, inspect its describe, query and action tools, and query the catalogue through an AI agent. The session distinguishes this runtime adapter from the development-time MCP server and demonstrates automatic registration of the running service with a local agent. The recording describes the adapter as beta in July 2026, with read-only queries and writes through unbound actions.
Examine the details of the Model Context Protocol on startupExamine the details of the Model Context Protocol on startupWhat the MCP adapter actually does when a CAP server boots, watched rather than described — the companion to the tutorial that switches it on.
Model Context Protocol Adapter — CAP guideModel Context Protocol Adapter — CAP guideDocuments @cap-js/mcp and com.sap.cds:cds-adapter-mcp, service annotations, generated describe/query/call tools and local client setup. The guide records Java doc-comment configuration, unbound-action-based data changes, incomplete XSUAA PKCE support and the adapter’s governance boundaries.
Third-Party MCP Server Access to SAP Solutions on BTPThird-Party MCP Server Access to SAP Solutions on BTPDescribes external MCP servers and custom servers on BTP, assigning their operators responsibility for authentication, scoped identity, API limits, logging and lifecycle. The permitted use remains conditional on the SAP API Policy, while SAP Integration Suite and Joule Studio are described as SAP-provided paths. Hosting a server on BTP does not automatically supply its governance controls.Dhawal Joshi, Harut Ter-Minasyan, Mirko Günther
WebSocketCommunity only
CAP WebSocketsCAP WebSocketsThe early one, from 2021, before an adapter existed to make it ordinary. Read for what the problem looked like when it had to be solved by hand.vvdries, published 2021-01-26
Communicate from a Java Application to ABAP via WebSocket RFC using JCo - Migration GuideCommunicate from a Java Application to ABAP via WebSocket RFC using JCo - Migration GuideWalks a JCo setup from classic CPIC-based RFC to WebSocket RFC: swap the application- or message-server logon properties for jco.client.wshost and jco.client.wsport, and implement DestinationDataProvider's getSSLContext (and, for mTLS, getClientCertificate) since the new connection runs over TLS. It covers building the PKI trust on both sides — a local PKCS12 keystore for the Java side, STRUST's SSL-Server Standard certificate exported and imported for mutual trust on the ABAP side — and notes that on BTP, JCo paired with the Destination service already implements this via the Connectivity service, so the custom SSLContext work can be skipped there.simon_luser, published 2025-01-21
SAP Event Mesh: S4 HANA On-Prem and SAP CI(BTP IS) through WebSocket and WebhooksSAP Event Mesh: S4 HANA On-Prem and SAP CI(BTP IS) through WebSocket and WebhooksA step-by-step walkthrough of wiring Event Mesh to publish and consume events between an on-premise S/4HANA system and Cloud Integration, contrasting persistent queues (one subscriber, kept until consumed) against unpersisted topics, and WebSocket's AMQP transport against webhook delivery for the same queue. Two tested findings support it: a queue consumer running in continuous consumption mode receives a message ahead of a webhook on the same topic, and a message stays queued and is retried (almost 8770 times in under a minute, in the author's test) until the consumer processes it successfully.FarooqAhmed, published 2023-10-03
XML payloadsCommunity only
@neoimpulse/cap-js-xml-protocol@neoimpulse/cap-js-xml-protocolA CAP plugin that lets the REST adapter take XML, parsing the payload to JSON and rewriting the content type before CAP sees the request.independent, cap
CAP plugin letting the REST adapter accept XML payloads
Analytical queriesSAP only
blog-cap-chartblog-cap-chartA Fiori elements overview page over a CAP service whose two donut-chart cards read the same measure from an aggregating view and from the plain entity, so what the aggregation annotations change is visible side by side.independent, cap
Fiori overview page comparing aggregated and plain donut-chart cards
Neither the package manifest nor the repository tree declares a licence.
Building an Analytical List Page with CAP OData V4Building an Analytical List Page with CAP OData V4The annotations a CAP OData V4 service needs before an Analytical List Page will render — the write-up behind the cap-alp sample indexed here. Candid about its provenance: the author credits a GitHub repository she found the approach in, and notes that the repository is no longer available, which is the whole argument for indexing the reasoning rather than only linking the code.published 2023-06-12
Building an Analytical List Page with CAP OData V4
cap-alp: no published releases, repository quiet for 24 months. Affects A recipe, Runnable code.
Discovering SAP Fiori Elements Analytical functions by implementing SAP Support Message ReportingDiscovering SAP Fiori Elements Analytical functions by implementing SAP Support Message ReportingAnalytical annotations learned by building something the author wanted — a view over SAP support messages — after a conversation in February 2021 that the post dates precisely. Exploration written up as exploration.published 2021-03-14
E2E: SAP Cloud Platform Internet of Things to SAP Analytics CloudE2E: SAP Cloud Platform Internet of Things to SAP Analytics CloudDevice data from ingestion to chart, with CAP occupying the middle: a CDS-defined persistence on HANA Cloud, and an OData service published from it for Analytics Cloud to consume live. The interesting choice is that CAP is used for the model rather than for business logic — there is barely any.Gunter, published 2020-08-31
Empowering Your Data Analytics with GPT-3 and SAP CAP IntegrationEmpowering Your Data Analytics with GPT-3 and SAP CAP IntegrationFree text in, SQL out, answer back in a sentence — the model writes the query, CAP runs it, and the model turns the rows into prose. Written in the GPT-3 window, so the model access has dated, but the three-step shape has not, and it is a different bet from retrieval: nothing is embedded, the schema is the context.Former Member, published 2023-03-10
Fiori Elements Analytical Table with CAP: Does it work with V2 and V4?Fiori Elements Analytical Table with CAP: Does it work with V2 and V4?A question in the title and an answer in the post, with the boundary drawn carefully: this is an analytical table inside a List Report, not the Analytical List Page, and the two protocol versions do not behave the same.published 2023-04-03
Fiori Elements Analytical Table with CAP: Does it work with V2 and V4?
Fiori annotations changed in @sap/cds-dk 9.6.0, 2025-12-17. Affects Runnable code.
Predictive Asset Insights embedded Live analytics using CAP and SACPredictive Asset Insights embedded Live analytics using CAP and SACCAP as the layer between a line-of-business application's data and a live Analytics Cloud story embedded back into it — master data and operational data both. Structured as ten steps, which keeps it honest about how much of this is configuration rather than modelling.Saif, published 2021-07-18
SAP Data and Analytics Showcase - Develop a Machine Learning Application on SAP BTPSAP Data and Analytics Showcase - Develop a Machine Learning Application on SAP BTPThe overview post of a showcase written by three authors, setting out the dataset, the scenario and the solution map before any of it is built. Its job is to say which piece goes where across the SAP data and analytics portfolio; the CAP application is one station on that map rather than the subject.former_member10846, published 2022-08-12
SAP Data and Analytics Showcase – Use SAP Cloud Application Programming Model to Develop a Machine Learning Application on SAP BTPSAP Data and Analytics Showcase – Use SAP Cloud Application Programming Model to Develop a Machine Learning Application on SAP BTPThe instalment where the showcase becomes code: the CAP application built in Business Application Studio, and the sub-scenario it covers implemented step by step. The overview post is the one that says why this piece exists at all.former_member10846, published 2022-08-12
SAP Incentive Management - Understanding of CSN file & CLI Command to generateSAP Incentive Management - Understanding of CSN file & CLI Command to generateCSN met from the far end: not as CAP's compiled model but as the interchange format a product hands to Analytics Cloud so a story knows the shape of the data. Explains what CSN is, why the format matters here, and the command that produces one.Yogananda, published 2024-11-19
AttachmentsSAP and community
@tklein1801/cap-js-attachments@tklein1801/cap-js-attachmentsA CAP Node.js attachments plugin with a draft-based upload table, Object Store integration and configurable malware scanning for the files that are uploaded.independent, cap
CAP Node.js attachments plugin with Object Store and malware scanning
SAP Document Management service, integration optionSAP Document Management service, integration optionA BTP service of APIs and a reusable UI5 component for adding document management, with folders, versions and status, to a business application over SAP's repository or a CMIS-compliant one.sap official, btp
APIs and a UI5 component for document management in apps
sap-cap-sdm-pluginsap-cap-sdm-pluginA CAP Node.js plugin that maps annotated CDS entities to SAP Document Management and exposes CMIS and repository-administration clients, in an early release.independent, cap
CAP Node.js plugin mapping CDS entities to SAP Document Management
Archived The declared repository is archived.
Functional boundary For versioned or thumbnail-enabled repositories, or bulk upload and download, the [README](https://raw.githubusercontent.com/vneecious/sap-cap-sdm-plugin/d9f036b16542e5c5b9b6dc704e0ba5f880193212/README.md) labels this an “early release” and lists those features as unsupported.
Building an Attachment Upload and Download Solution Using UploadSetwithTable ControlBuilding an Attachment Upload and Download Solution Using UploadSetwithTable ControlThe successor control to UploadSet posts the file in one request by default, and against CAP that is wrong: the record has to be created first and the content put to it afterwards. The author states the two-step shape plainly and notes it may not apply to an ABAP backend, which is the kind of boundary that usually goes unsaid. Written during a proof of concept for a reusable attachment component, and it carries the problem they hit with the control.published 2025-03-13
Consume SAP Document Management using @cap-js/sdm pluginConsume SAP Document Management using @cap-js/sdm pluginStoring attachments in a SAP Document Management repository from a CAP application, using the official plugin. The point the post makes about the plugin is that it brings its own UI: a user attaches any number of documents and one Save writes them all to the repository, so the application does not build an upload surface of its own.published 2024-08-26
Extend Upload Set to Fiori Elements and utilize Document Management ServiceExtend Upload Set to Fiori Elements and utilize Document Management ServiceWritten two months before there was an official plugin, and the author has left the record of that in the page: an update dated 2024-04-04 noting the CAP team released @cap-js/attachments, and another dated 2024-05-21 saying they tested it and wrote up the Object Store variant separately. The hand-built version underneath is still the answer when the plugin's storage choices do not fit.published 2024-02-25
Extend Upload Set to Fiori Elements and utilize Document Management Service
Attachments has changed 3 times since this was published, most recently in @cap-js/sdm 1.0.0, 2024-06-26. Affects Runnable code.
Extend Upload Set with Table to Fiori Elements and utilize Object StoreExtend Upload Set with Table to Fiori Elements and utilize Object StoreThe Object Store variant of the author's earlier Document Management post, written after testing @cap-js/attachments — a sample managing text and file information together, and offered as something for people new to BTP rather than as a pattern.published 2024-05-21
Extend Upload Set with Table to Fiori Elements and utilize Object Store
Fiori annotations changed in @sap/cds-dk 9.6.0, 2025-12-17. Affects Runnable code.
How to transfer file from CAP backsideHow to transfer file from CAP backsideA PDF arriving from the front end, stored against the record with @Core.MediaType, and then sent on to an external service for parsing. Short, and the second half is the part that is not in the plugin documentation: getting the bytes back out of the model to forward them somewhere else.published 2023-09-14
How to transfer file from CAP backside
Attachments has changed 3 times since this was published, most recently in @cap-js/sdm 1.0.0, 2024-06-26. Affects Runnable code.
Presenting sap-cap-sdm-plugin: Effortless Integration Between CAP (Node.js) and DMSPresenting sap-cap-sdm-plugin: Effortless Integration Between CAP (Node.js) and DMSThe author's introduction of the plugin, and unusually clear about its lineage: the idea came from a post about cds.plugins whose example did nothing more than append an emoji to annotated properties, and the groundwork was an earlier library, sap-cloud-cmis-client, that this builds on. Worth reading for how a plugin gets conceived as much as for what it does with Document Management Service.published 2023-10-02
Presenting sap-cap-sdm-plugin: Effortless Integration Between CAP (Node.js) and DMS
sap-cap-sdm-plugin is archived. Its last release was 2024-03-24. Affects Runnable code.
Unlocking Efficiency: Leveraging SAP BTP Document Management Service in Fiori Applications # 2Unlocking Efficiency: Leveraging SAP BTP Document Management Service in Fiori Applications # 2Document Management's own Attachment Reuse UI dropped into a Fiori elements List Report, in two variants — OData V2, and OData V4 in a CAP application. The CAP half is one of the two scenarios rather than the subject; the rest of the series is about custom Fiori apps and a process task UI, with no CAP in them.published 2024-12-10
Upload attachments in a Freestyle UI5 and CAP appUpload attachments in a Freestyle UI5 and CAP appAttachments where the UI is freestyle rather than Fiori elements, so none of the generated upload behaviour applies and both ends have to be written.published 2023-12-19
Uploading attachment with cap-js/attachment plugins but via External App/PostmanUploading attachment with cap-js/attachment plugins but via External App/PostmanThe plugin is written for a Fiori elements front end; this is the case where the caller is neither — Postman and a React app. Short, and it exists because the request shape is not obvious from outside the generated UI: what to POST, what to PUT, and in which order.published 2025-07-24
Use SAP Document Management Service Plugin In CAP NODEJS Step by Step GuidanceUse SAP Document Management Service Plugin In CAP NODEJS Step by Step GuidanceThe official plugin is documented in capire; this is somebody who set it up anyway and wrote down where it went wrong. The author says as much — the point is to spare customers the troubles, so the value is in the order of the steps and the prerequisites, not in the API.Jacky_Liu1, published 2025-03-06
Working with the Attachment plugin - Cloud Application ProgrammingWorking with the Attachment plugin - Cloud Application ProgrammingOne instalment of the author's own series working through the CAP plugins one at a time, and it reads as that: what the plugin does, how it does it, and how to put it in a service. Written from the plugin list in capire rather than from a problem, which makes it the plainest introduction here.published 2024-05-18
Working with the Attachment plugin - Cloud Application Programming
@cap-js/attachments has been through 3 major lines since this was published: 2 (2025-03), 3 (2025-10), 4 (2026-08). Affects A recipe, Runnable code.
CachingSAP and community
Redis on SAP BTP, hyperscaler optionRedis on SAP BTP, hyperscaler optionA managed Redis from the underlying hyperscaler, consumed through a BTP service binding rather than run yourself.sap official, btp
Managed Redis from the hyperscaler via a BTP service binding
Boosting performance in SAP Cloud Application Programming Model (CAP) applications with cds-cachingBoosting performance in SAP Cloud Application Programming Model (CAP) applications with cds-cachingThe plugin's introduction post: what cds-caching is for, how it is put together and the cases it was written against. The edge holds because the plugin's README still points here as the piece to read first, so this is where a reader arriving at the plugin is sent. It predates version 1.0 and the API has moved since: the read-through calls it shows as cache.run() and cache.send() are the ones the README now lists as deprecated in favour of cache.rt.*, which returns the cache key and hit/miss metadata alongside the result, and 1.0 made user, tenant and locale awareness opt-in under keyManagement rather than folding them into request-based keys by default. Metrics and monitoring, the OData API and full TypeScript definitions arrived with 1.0 and are described in CAP just got faster: What's new in cds-caching 1.0 instead. The reasoning about when a CAP service wants a cache still reads true; the call sites need translating.published 2025-06-25
Boosting performance in SAP Cloud Application Programming Model (CAP) applications with cds-caching
cds 9, maintenance until 2027-06, cds-caching 0.x, now 3.1.1. Affects A recipe.
CAP just got faster: What's new in cds-caching 1.0CAP just got faster: What's new in cds-caching 1.0What changed in cds-caching at 1.0, announced at reCAP 2025 by the plugin's own maintainer. The substantive change is the read-through API: cache.rt.run(), send(), exec() and wrap() replace the bare cache.run() and cache.send(), and each returns the cache key and hit-or-miss metadata beside the result rather than the value alone. The second is quieter and easier to miss on an upgrade: user, tenant and locale stopped being folded into request-based cache keys by default and became opt-in through keyManagement, or per operation through a key template. Both of those still describe 3.x. What does not is the second half of the post: the metrics configuration it shows was reshaped at 2.0 and the statistics and dashboard settings were removed at 3.0, so take the monitoring and dashboard sections from the README instead. Read it as the successor to the introduction post, which still shows the deprecated calls.published 2025-07-15
CAP just got faster: What's new in cds-caching 1.0
cds-caching 1.0, now 3.1.1, cds 9, maintenance until 2027-06. Affects A reference.
Performance Boost and Caching Strategy for Faster Data Access using "cds-caching" in SAP CAPPerformance Boost and Caching Strategy for Faster Data Access using "cds-caching" in SAP CAPSomebody else's account of using the plugin, which is the useful counterpart to its documentation. The case is specific: a master-data entity of more than a million rows, rarely written and constantly read, where the read-heavy shape is what makes caching worth the complexity rather than a general performance wish. Walks through integrating cds-caching into that application and what it changed.NaveenChandar, published 2025-03-04
Performance Boost and Caching Strategy for Faster Data Access using "cds-caching" in SAP CAP
cds-caching has been through 4 major lines since this was published, most recently 1 (2025-07), 2 (2026-07), 3 (2026-08). Affects A recipe, Runnable code.
Concurrency controlSAP and community
[Part – 2] Enrich CAP based Services with Behaviors using Annotations[Part – 2] Enrich CAP based Services with Behaviors using AnnotationsThe second half of a two-part walkthrough of CAP's behavioral annotations, following on from access control and input validation in the first part. This post works through @cds.autoexpose, @cds.api.ignore, @cds.persistence.exists/skip, @cds.on.insert/@cds.on.update and the @odata.Type/@odata.singleton mapping overrides, all shaping how a CDS model is projected into a service, which is data modelling. Alongside these it covers @cds.query.limit for default and maximum page sizes (pagination and streaming), @odata.etag with exclusive and shared locks for optimistic concurrency (concurrency control), and @cds.search for scoping $search to chosen elements (search), each with a CDS code example.published 2023-01-29
Data federationSAP and community
The Full Picture: Federating, Replicating, and Caching Remote Data in CAP — Part 1The Full Picture: Federating, Replicating, and Caching Remote Data in CAP — Part 1Part one of two, and the concepts half: terminology, what CAP already does, and what a project still has to write. It fixes a vocabulary — federation is the umbrella for making remote data part of your model, delegation forwards each request to the remote at query time, replication is a scheduled copy into the local database, and caching is an option on either rather than a third strategy — which collides with CAP's own, since what this series calls replication is what the CAP-level Data Federation guide calls federation. From the ground the Service Integration guide covers, it lists what is left to hand-write: cross-service $expand, navigation filters across the boundary, write forwarding, timeouts and retries, then scheduling, delta detection, backoff, a guard for two app instances sharing one schedule, idempotent writes, and knowing whether the last run succeeded. That list is why the edge to cds-data-federation holds: the second half maps it onto @federation.delegate and @federation.replicate and says which package carries which part — annotations in cds-data-federation, the scheduled engine in cds-data-pipeline, response caching through cds-caching — so it is the design rationale for the annotations, not the API reference. The gap list and the plugins answering it come from the same person who maintains them; cap-replication-demo and SAP's xtravels sample are cited as the hand-written form of the same work. Part 2 is announced as a walkthrough of a demo application and is not covered here.
Data modellingSAP and community
#CAP-TechBytes Input Validation#CAP-TechBytes Input ValidationThe annotations one at a time — @mandatory, @assert.unique, @assert.range including the enum form, @assert.format — each with what it produces. Ends on error handling, which is the part that decides whether any of it is usable from a UI.Thajunniza, published 2023-07-07
A CAP Plugin for Flexible Number Range Management: cds-numberrange-pluginA CAP Plugin for Flexible Number Range Management: cds-numberrange-pluginThe author's own plugin, and the reason given for writing it is about plugins rather than about number ranges: a year of using them convinced them that this was the way to extend CAP without leaving marks on the application. Sequential document numbers are the thing it does; keeping the host project clean is the thing it argues for.abdulbasit, published 2025-06-17
Analyze and optimize ABAP Cloud model apps built on core data servicesAnalyze and optimize ABAP Cloud model apps built on core data servicesPerformance anti-patterns in data models built with ABAP CDS under ABAP Cloud applications, and the tools that find them: the abstract names ABAP cross trace, the SQL analyzer (PlanViz) in Visual Studio Code and the SAP HANA database explorer as what the session uses to follow a bottleneck from the application to the database. The anti-patterns are taken from real business applications, which is where the data modelling edge holds; which ones are shown is not in the abstract. A TechEd 2026 session (Tuesday 27 October, Berlin), presented by Ingo Braeuninger, Robert Werlich, Steffen Siegmund and Thomas Fiedler, written here from SAP's abstract; the recording is not yet published.
CAP, CDS, CDL, CSN and jq - finding associationsCAP, CDS, CDL, CSN and jq - finding associationsHow associations are actually represented once CDL is compiled into CSN, worked out by parsing the machine-readable form with jq. Useful less as a recipe than as a way in: anything that wants to reason about a CDS model without the compiler has to read CSN, and this is what that looks like from the outside.published 2024-04-16
Computed field example in CAPComputed field example in CAPAn answer to a Community question — how to count the entities on the far side of an association — written up as a short post rather than left in a thread. The answer combines CDS with Node.js service events, which is the seam worth noticing: some of what looks like modelling is expressed in the model and some has to be computed when the request arrives, and the boundary between them is not obvious from either side.published 2019-08-21
Computed field example in CAP
Data modelling has changed 3 times since this was published, most recently in @sap/cds 9.9.0, 2026-04-23. Affects A recipe, Runnable code.
Create CDS Views and expose through OData service in CAPMCreate CDS Views and expose through OData service in CAPMViews defined in CDS and then exposed, which is the whole of what a small CAP service is. Written step by step from cds init onward in Business Application Studio.VenkateshMundru, published 2025-08-11
Creating structured types, enums and named aspects using the CDS Graphical ModelerCreating structured types, enums and named aspects using the CDS Graphical ModelerThe modelling constructs that are awkward to draw — structured types, enums, named aspects — done in the graphical modeller rather than in CDL.Xiao-fei_Song, published 2021-05-26
Develop a full stack Business application with SAP Cloud Application Programming ModelDevelop a full stack Business application with SAP Cloud Application Programming ModelBuilds a full-stack CAP application in SAP Web IDE Full Stack's now-retired 'SAP Cloud Platform Business Application' template: a data-model.cds entity with its own service definition, then Fiori annotations on the generated OData. Building the project compiles that model into Catalog.xml and csn.json, the EDMX and CSN that metadata publishing says every exposed service gets. The entity and service definitions it writes by hand are the basic shape data modelling covers, though the webIDE and MTA tooling staged around them is gone.former_member584731, published 2018-11-29
First Java Cap ApplicationFirst Java Cap ApplicationA step-by-step walkthrough of a first CAP Java project: com.sap.cds:cds-services-archetype scaffolds the initial Maven project, and the domain model is then rewritten in the db folder with entities, the cuid and managed aspects, associations, compositions and a CodeList, so a hand-coded event handler serving a single entity gives way to a service that CAP's generic persistence handling serves without custom code. It deploys that model to SQLite for local development — cds deploy --to sqlite, then a Spring profile pointing at the generated database file — and ends by adding an index.cds so the model and service can be published as a reusable npm module.bruce_wang3, published 2020-12-08
Importing @sap/cds common.cds to your CAP project using the CDS Graphical ModelerImporting @sap/cds common.cds to your CAP project using the CDS Graphical ModelerPulling the common aspects and code lists from @sap/cds into a model through the modeller, so the reuse types appear in the diagram rather than only in the file.Xiao-fei_Song, published 2021-05-06
Learn how to define constraints declaratively in your CDS modelLearn how to define constraints declaratively in your CDS modelConstraints expressed in the model rather than checked in a handler — the distinction the atlas draws between input validation the framework enforces and validation somebody writes.SAP
SAP CAP Adapter to expose OData as custom REST ServiceSAP CAP Adapter to expose OData as custom REST ServiceWalks through consuming an external OData V2 service in a CAP project — cds import converts the Northwind service's EDMX into a CSN and cds.connect.to wires up the remote proxy — then re-exposing it as plain REST with the @protocol:'rest' annotation instead of OData's own envelope. Shows two ways to reshape the response, renaming and dropping fields in a CDS projection or rewriting the returned objects in a custom service handler, and remaps ?pageSize and ?offset onto OData's $top and $skip in that same handler.Former Member, published 2021-09-15
SAP CAP Recent Enhancements the HANA Dev Should Know AboutSAP CAP Recent Enhancements the HANA Dev Should Know AboutThomas Jung walks through CAP features for HANA database developers that landed through late 2021: doc comments in the data model (CDL comments propagated into generated database objects via the package.json cdsc.docs compiler option), and schema evolution reaching general availability in the November 2021 release, using the @cds.persistence.journal annotation and cds.hana.journal settings to generate incremental hdbmigrationtable migration scripts instead of dropping and recreating tables. It also walks through two features outside those two: window functions in view column definitions, added in the December 2021 release, and a beta assert_integrity setting that generates database foreign-key constraints from 1:1 associations and compositions.published 2022-02-15
SAP CAP(Cloud Application Programming)开发框架概述SAP CAP(Cloud Application Programming)开发框架概述A Chinese-language walkthrough of CAP built mainly from CAPire's own "About CAP" page: CDS entities, associations, compositions and aspects for data modelling, with an extend Books with @restrict: [{ grant:'WRITE', to:'admin' }] aspect as its authorization example; CQL and CQN queries shown against both a local service and OData's $select/$expand; and the service-and-event model — this.on, this.emit, srv.on — that carries CAP's async processing. It closes with the author's own setup: installing @sap/cds-dk, scaffolding a bookshop project with cds init, and running it with cds watch against local SQLite, mocked authentication and file-based messaging standing in for HANA Cloud, IAS and Kafka.ArthurYang, published 2024-01-07
SAP Cloud Platform Backend service: Tutorial [11]: CDS : magic: key: generationSAP Cloud Platform Backend service: Tutorial [11]: CDS : magic: key: generationExplains CDS's UUID key type: giving a key property UUID gets its value generated automatically instead of a hand-picked unused number, as data modelling lets an element's type do, at the cost of a 36-character value unfit for a user-facing display. It then works out how that generated value is addressed in a single-entity read URL — bare brackets in OData V4 against the guid'...' literal V2 requires — citing the OData specification for the difference.CarlosRoggan, published 2019-03-15
Understanding Projections in CAPM: Select Only What You Need!Understanding Projections in CAPM: Select Only What You Need!One concept, explained by someone who had just learned it and says so — what a projection is, why it matters, and an analogy. The register is unusual here and suits the subject: projections are the first thing that makes CDS feel different from a table.Avisek_, published 2025-06-10