Overview
This node enables interaction with a FHIR (Fast Healthcare Interoperability Resources) server, allowing users to perform various operations on FHIR resources. Specifically, the VRead operation retrieves a specific version of a FHIR resource by its ID and version ID. This is useful in healthcare scenarios where historical versions of patient records or clinical data need to be accessed for auditing, compliance, or clinical review.
Practical examples include:
- Retrieving a previous version of a patient's medical record.
- Accessing a specific revision of a diagnostic report for comparison.
- Auditing changes made to a medication request over time.
Properties
| Name | Meaning |
|---|---|
| Authentication | The method used to authenticate requests. Options: Basic Auth, Custom Auth, Digest Auth, Header Auth, None, OAuth1, OAuth2, Query Auth. |
| Base URL | The base URL of the FHIR server API to which requests are sent. Required when using certain authentication methods. |
| Resource Type | The type of FHIR resource to operate on (e.g., Patient, Observation, MedicationRequest). A comprehensive list of standard FHIR resource types is provided, plus an option for custom resource types. |
| Custom Resource Type | If "Resource Type" is set to "- Custom -", this string specifies the custom resource type name. |
| Tenant ID | Optional tenant identifier included in request headers to support multi-tenant FHIR servers. |
| ID | The unique identifier of the FHIR resource instance to retrieve. Required for VRead operation. |
| Version ID | The specific version identifier of the resource to retrieve. Required for VRead operation. |
| Specify Query Parameters | How query parameters are specified: either as key-value pairs or as raw JSON. |
| Query Parameters | Key-value pairs of query parameters to include in the request URL. |
| JSON | Raw JSON object representing query parameters if specifying them as JSON. |
| FHIR Path | An optional FHIRPath expression to extract specific data from the response JSON. |
| Ignore SSL Issues | Whether to ignore SSL certificate validation errors when connecting to the FHIR server. Useful for development or self-signed certificates. |
Output
The output is a JSON object representing the requested FHIR resource version. If the resource is a Bundle, it extracts and returns individual entries accordingly. The structure corresponds directly to the FHIR resource JSON schema, including all fields and metadata such as resourceType, id, and meta.versionId.
If a FHIRPath expression is provided, the output will be filtered to return only the data matching that expression.
No binary data output is produced by this operation.
Dependencies
- Requires access to a FHIR server endpoint supporting the FHIR RESTful API.
- Supports multiple authentication methods; appropriate credentials or tokens must be configured in n8n.
- Uses the
fhirpathlibrary internally to evaluate FHIRPath expressions. - Network connectivity and proper SSL configuration are necessary unless ignoring SSL issues is enabled.
Troubleshooting
- Invalid JSON in Query or Body: If JSON input fields contain invalid JSON, the node throws an error indicating the parameter with invalid JSON. Ensure JSON syntax correctness.
- Resource Not Found: If the specified resource ID or version does not exist, the FHIR server may return a 404 error. Verify the IDs and version IDs are correct.
- Authentication Errors: Incorrect or missing authentication credentials will cause authorization failures. Confirm that the selected authentication method is properly configured.
- Multiple Results Error: For search operations (not VRead), if the option to error on multiple results is enabled and more than one result is returned, an error is thrown.
- SSL Certificate Issues: If connecting to a server with invalid or self-signed certificates, enable "Ignore SSL Issues" to bypass validation during testing.
- Unsupported Operation: If an unsupported operation is selected, the node throws an error indicating the operation is not supported.