> For the complete documentation index, see [llms.txt](https://jembi.gitbook.io/openhim-platform/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://jembi.gitbook.io/openhim-platform/packages/fhir-datastore-hapi-fhir.md). # FHIR Datastore HAPI FHIR The HAPI FHIR service will be used for two mandatory functionalities: * A validator of FHIR messages * A storage of FHIR message ### A validator Incoming messages from an EMR or Postman bundles are not always well structured and it may be missing required elements or be malformed. HAPI FHIR will use a FHIR IG to validate these messages. It will reject any invalid resources and it will return errors according to the IG. HAPI FHIR is the first check to make sure the data injected in the rest of the system conforms to the requirements. ### A storage Backed by a PostgreSQL database, all the validated incoming messages will be stored. This will allow HAPI FHIR to check for correct links and references between the resources, as well as another storage for backups in case the data is lost. --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://jembi.gitbook.io/openhim-platform/packages/fhir-datastore-hapi-fhir.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.