STU 3 Candidate

This page is part of the FHIR Specification (v1.4.0: STU 3 Ballot 3). The current version which supercedes this version is 5.0.0. For a full list of available versions, see the Directory of published versions . Page versions: R5 R4B R4 R3 R2

6.7 Resource Binary - Content

FHIR Infrastructure Work GroupMaturity Level: 1Compartments: Not linked to any defined compartments

A binary resource can contain any content, whether text, image, pdf, zip archive, etc.

6.7.1 Scope and Usage

There are situations where it is useful or required to handle pure binary content using the same framework as other resources. Typically, this is when the binary content is referred to from other FHIR Resources. Using the same framework means that the existing servers, security arrangements, code libraries etc. can handle additional related content. Typically, Binary resources are used for handling content such as:

  • CDA Documents (i.e. with XDS)
  • PDF Documents
  • Images (the Media resource is preferred for handling images, but not possible when the content is already binary - XDS)

A binary resource can contain any content, whether text, image, pdf, zip archive, etc. These resources are served in their native form on the rest interface, but can also be represented in XML or JSON, such as when including these resources in a bundle (used when it is convenient to include these in the feed directly rather than leaving them by reference).

6.7.2 Boundaries and Relationships

This resource is generally used as the target of a Document Reference or an Attachment, when a FHIR server finds it convenient to manage the content within the same overall REST framework as the other resources.

6.7.3 Resource Content

Structure

NameFlagsCard.TypeDescription & Constraintsdoco
.. Binary ΣResourcePure binary content defined by some other format than FHIR
... contentType Σ1..1codeMimeType of the binary content
MimeType (Required)
... content Σ1..1base64BinaryThe actual content

doco Documentation for this format

XML Template

<Binary xmlns="http://hl7.org/fhir"> doco
 <!-- from Resource: id, meta, implicitRules, and language -->
 <contentType value="[code]"/><!-- 1..1 MimeType of the binary content  -->
 <content value="[base64Binary]"/><!-- 1..1 The actual content -->
</Binary>

JSON Template

 

Alternate definitions: Schema/Schematron, Resource Profile (XML, JSON), Questionnaire

6.7.3.1 Terminology Bindings

PathDefinitionTypeReference
Binary.contentType The mime type of an attachment. Any valid mime type is allowed.RequiredBCP 13 (RFCs 2045, 2046, 2047, 4288, 4289 and 2049)

6.7.3.2 Serving Binary Resources using the RESTful API

Binary resources behave slightly differently to all other resources on the RESTful API. Specifically, when a read request is made for the binary resource that doesn't explicitly specify the FHIR content types "application/xml+fhir" or "application/json+fhir", then the content should be returned using the content type stated in the resource. e.g. if the content type in the resource is "application/pdf", then the content should be returned as a PDF directly.

Note that due to the way the web infrastructure works, it is not possible to make blanket rules about the relationship between the "Accept" field in the HTTP request, and the return type, which is why there is no hard rule about this. However the intent is that unless specifically requested, the FHIR XML/JSON representation is not returned.

Note that in the native binary representation, the normal resource metadata is not available directly, though some of it is replicated in the HTTP response headers.

When a binary is written the server (create/update - POST or PUT), the data is accepted as is and treated as a the binary content of a Binary, including when the content type is "application/xml+fhir" or "application/json+fhir", except for the special case where the content is actually a Binary resource.

6.7.3.3 Security Considerations

Binary resources are not constrained, and therefore can be of any content type and encoding. Therefore extra care needs to be taken to validate the content of the Binary resource against malicious or malformed content. For more details see Security of Narrative.

6.7.4 Search Parameters

Search parameters for this resource. The common parameters also apply. See Searching for more information about searching in REST, messaging, and services.

NameTypeDescriptionPaths
contenttypetokenMimeType of the binary contentBinary.contentType