pca-subscription
type: StructureDefinition
node role: treeRoot
id:
  v: pca-subscription
text:
  status:
    v: extensions
  div:
    v: Generated Narrative: StructureDefinition pca-subscription Name Flags Card. Type Description & Constraints<img src="[binary]" alt="doco" style="background-color: inherit"/> Subscription 0..* Subscription Server push subscription criteria #xD; status S 1..1 code requested | active | error | off #xD; reason S 1..1 string Description of why this subscription was created Fixed Value: subscriber change notifications #xD; criteria S 1..1 string Rule for server push #xD; channel #xD; type S 1..1 code rest-hook | websocket | email | sms | message Fixed Value: rest-hook #xD; endpoint S 0..1 url Where the channel points to #xD; payload 0..0 MIME type to send, or omit for no payload #xD; header S 0..* string Usage depends on the channel type #xD; <img src="[binary]" alt="doco" style="background-color: inherit"/> Documentation for this format
url:
  v: http://pca.digitalhealth.gov.au/fhir/4.0/StructureDefinition/pca-subscription
  l: pca-subscription
version:
  v: 25.2.0.1
name:
  v: PcaSubscription
title:
  v: PCA Subscription
status:
  v: active
date:
  v: 2025-12-02T13:23:30+10:00
publisher:
  v: Australian Digital Health Agency
contact:
  telecom:
    system:
      v: email
description:
  v: This profile is used by subscribing systems to register for notifications from the PCA service when new or updated service offerings are available, or when publication of existing service offerings has been newly revoked.
use context:
  code:
    system:
      v: http://terminology.hl7.org/CodeSystem/usage-context-type
      l: usage-context-type
    code:
      v: jurisdiction
  value: CodeableConcept
    coding:
      system:
        v: urn:iso:std:iso:3166
        l: 3166
      code:
        v: AU
      display:
        v: Australia
copyright:
  v: Copyright © 2024 Australian Digital Health Agency - All rights reserved. This content is licensed under a Creative Commons Attribution 4.0 International License. See https://creativecommons.org/licenses/by/4.0/.
fhir version:
  v: 4.0.1
mapping:
  identity:
    v: rim
  uri:
    v: http://hl7.org/v3
    l: v3
  name:
    v: RIM Mapping
mapping:
  identity:
    v: w5
  uri:
    v: http://hl7.org/fhir/fivews
    l: fivews
  name:
    v: FiveWs Pattern Mapping
kind:
  v: resource
abstract:
  v: false
type:
  v: Subscription
  l: Subscription
base definition:
  v: http://hl7.org/fhir/StructureDefinition/Subscription
  l: Subscription
derivation:
  v: constraint
snapshot:
  extension:
    url:
      v: http://hl7.org/fhir/tools/StructureDefinition/snapshot-base-version
      l: snapshot-base-version
    value: String
      v: 4.0.1
  element:
    id:
      v: Subscription
    path:
      v: Subscription
    short:
      v: Server push subscription criteria
    definition:
      v: The subscription resource is used to define a push-based subscription from a server to another system. Once a subscription is registered with the server, the server checks every resource that is created or updated, and if the resource matches the given criteria, it sends a message on the defined "channel" so that another system can take an appropriate action.
    alias:
      v: WebHook
    alias:
      v: Hook
    alias:
      v: Routing Rule
    min:
      v: 0
    max:
      v: *
    base:
      path:
        v: Subscription
      min:
        v: 0
      max:
        v: *
    constraint:
      key:
        v: dom-2
      severity:
        v: error
      human:
        v: If the resource is contained in another resource, it SHALL NOT contain nested Resources
      expression:
        v: contained.contained.empty()
      xpath:
        v: not(parent::f:contained and f:contained)
      source:
        v: http://hl7.org/fhir/StructureDefinition/DomainResource
        l: DomainResource
    constraint:
      key:
        v: dom-3
      severity:
        v: error
      human:
        v: If the resource is contained in another resource, it SHALL be referred to from elsewhere in the resource or SHALL refer to the containing resource
      expression:
        v: contained.where((('#'+id in (%resource.descendants().reference | %resource.descendants().as(canonical) | %resource.descendants().as(uri) | %resource.descendants().as(url))) or descendants().where(reference = '#').exists() or descendants().where(as(canonical) = '#').exists() or descendants().where(as(canonical) = '#').exists()).not()).trace('unmatched', id).empty()
      xpath:
        v: not(exists(for $id in f:contained/*/f:id/@value return $contained[not(parent::*/descendant::f:reference/@value=concat('#', $contained/*/id/@value) or descendant::f:reference[@value='#'])]))
      source:
        v: http://hl7.org/fhir/StructureDefinition/DomainResource
        l: DomainResource
    constraint:
      key:
        v: dom-4
      severity:
        v: error
      human:
        v: If a resource is contained in another resource, it SHALL NOT have a meta.versionId or a meta.lastUpdated
      expression:
        v: contained.meta.versionId.empty() and contained.meta.lastUpdated.empty()
      xpath:
        v: not(exists(f:contained/*/f:meta/f:versionId)) and not(exists(f:contained/*/f:meta/f:lastUpdated))
      source:
        v: http://hl7.org/fhir/StructureDefinition/DomainResource
        l: DomainResource
    constraint:
      key:
        v: dom-5
      severity:
        v: error
      human:
        v: If a resource is contained in another resource, it SHALL NOT have a security label
      expression:
        v: contained.meta.security.empty()
      xpath:
        v: not(exists(f:contained/*/f:meta/f:security))
      source:
        v: http://hl7.org/fhir/StructureDefinition/DomainResource
        l: DomainResource
    constraint:
      extension:
        value: Boolean
      extension:
        value: Markdown
      key:
        v: dom-6
      severity:
        v: warning
      human:
        v: A resource should have narrative for robust management
      expression:
        v: text.`div`.exists()
      xpath:
        v: exists(f:text/h:div)
      source:
        v: http://hl7.org/fhir/StructureDefinition/DomainResource
        l: DomainResource
    is modifier:
      v: false
    is summary:
      v: false
    mapping:
      identity:
        v: rim
      map:
        v: Entity. Role, or Act
    mapping:
      identity:
        v: rim
      map:
        v: N/A
  element:
    id:
      v: Subscription.id

Boolean
v: true

Markdown
v: When a resource has no narrative, only systems that fully understand the data can display the resource to a human safely. Including a human readable representation in the resource makes for a much more robust eco-system and cheaper handling of resources by intermediary systems. Some ecosystems restrict distribution of resources to only those systems that do fully understand the resources, and as a consequence implementers may believe that the narrative is superfluous. However experience shows that such eco-systems often open up to new participants over time.

v: Subscription.id

v: Logical id of this artifact

v: The logical id of the resource, as used in the URL for the resource. Once assigned, this value never changes.

v: The only time that a resource does not have an id is when it is being submitted to the server using a create operation.

v: 0

v: 1

path:
  v: Resource.id
min:
  v: 0
max:
  v: 1

extension:
  url:
    v: http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type
    l: structuredefinition-fhir-type
  value: Url
    v: id
    l: id
code:
  v: http://hl7.org/fhirpath/System.String
  l: System.String

v: false

v: true

id:
  v: Subscription.meta
path:
  v: Subscription.meta
short:
  v: Metadata about the resource
definition:
  v: The metadata about the resource. This is content that is maintained by the infrastructure. Changes to the content might not always be associated with version changes to the resource.
min:
  v: 0
max:
  v: 1
base:
  path:
    v: Resource.meta
  min:
    v: 0
  max:
    v: 1
type:
  code:
    v: Meta
    l: Meta
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
is modifier:
  v: false
is summary:
  v: true

id:
  v: Subscription.implicitRules
path:
  v: Subscription.implicitRules
short:
  v: A set of rules under which this content was created
definition:
  v: A reference to a set of rules that were followed when the resource was constructed, and which must be understood when processing the content. Often, this is a reference to an implementation guide that defines the special rules along with other profiles etc.
comment:
  v: Asserting this rule set restricts the content to be only understood by a limited set of trading partners. This inherently limits the usefulness of the data in the long term. However, the existing health eco-system is highly fractured, and not yet ready to define, collect, and exchange data in a generally computable sense. Wherever possible, implementers and/or specification writers should avoid using this element. Often, when used, the URL is a reference to an implementation guide that defines these special rules as part of it's narrative along with other profiles, value sets, etc.
min:
  v: 0
max:
  v: 1
base:
  path:
    v: Resource.implicitRules
  min:
    v: 0
  max:
    v: 1
type:
  code:
    v: uri
    l: uri
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
is modifier:
  v: true
is modifier reason:
  v: This element is labeled as a modifier because the implicit rules may provide additional knowledge about the resource that modifies it's meaning or interpretation
is summary:
  v: true

id:
  v: Subscription.language
path:
  v: Subscription.language
short:
  v: Language of the resource content
definition:
  v: The base language in which the resource is written.
comment:
  v: Language is provided to support indexing and accessibility (typically, services such as text to speech use the language tag). The html language tag in the narrative applies to the narrative. The language tag on the resource may be used to specify the language of other presentations generated from the data in the resource. Not all the content has to be in the base language. The Resource.language should not be assumed to apply to the narrative automatically. If a language is specified, it should it also be specified on the div element in the html (see rules in HTML5 for information about the relationship between xml:lang and the html lang attribute).
min:
  v: 0
max:
  v: 1
base:
  path:
    v: Resource.language
  min:
    v: 0
  max:
    v: 1
type:
  code:
    v: code
    l: code
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
is modifier:
  v: false
is summary:
  v: false
binding:
  extension:
    url:
      v: http://hl7.org/fhir/StructureDefinition/elementdefinition-maxValueSet
      l: elementdefinition-maxValueSet
    value: Canonical
      v: http://hl7.org/fhir/ValueSet/all-languages
      l: all-languages
  extension:
    url:
      v: http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName
      l: elementdefinition-bindingName
    value: String
      v: Language
  strength:
    v: preferred
  description:
    v: A human language.
  value set:
    v: http://hl7.org/fhir/ValueSet/languages|4.0.1
    l: http://hl7.org/fhir/ValueSet/languages

id:
  v: Subscription.text
path:
  v: Subscription.text
short:
  v: Text summary of the resource, for human interpretation
definition:
  v: A human-readable narrative that contains a summary of the resource and can be used to represent the content of the resource to a human. The narrative need not encode all the structured data, but is required to contain sufficient detail to make it "clinically safe" for a human to just read the narrative. Resource definitions may define what content should be represented in the narrative to ensure clinical safety.
comment:
  v: Contained resources do not have narrative. Resources that are not contained SHOULD have a narrative. In some cases, a resource may only have text with little or no additional discrete data (as long as all minOccurs=1 elements are satisfied). This may be necessary for data from legacy systems where information is captured as a "text blob" or where text is additionally entered raw or narrated and encoded information is added later.
alias:
  v: narrative
alias:
  v: html
alias:
  v: xhtml
alias:
  v: display
min:
  v: 0
max:
  v: 1
base:
  path:
    v: DomainResource.text
  min:
    v: 0
  max:
    v: 1
type:
  code:
    v: Narrative
    l: Narrative
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: Act.text?

id:
  v: Subscription.contained
path:
  v: Subscription.contained
short:
  v: Contained, inline Resources
definition:
  v: These resources do not have an independent existence apart from the resource that contains them - they cannot be identified independently, and nor can they have their own independent transaction scope.
comment:
  v: This should never be done when the content can be identified properly, as once identification is lost, it is extremely difficult (and context dependent) to restore it again. Contained resources may have profiles and tags In their meta elements, but SHALL NOT have security labels.
alias:
  v: inline resources
alias:
  v: anonymous resources
alias:
  v: contained resources
min:
  v: 0
max:
  v: *
base:
  path:
    v: DomainResource.contained
  min:
    v: 0
  max:
    v: *
type:
  code:
    v: Resource
    l: Resource
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: N/A

id:
  v: Subscription.extension
path:
  v: Subscription.extension
short:
  v: Additional content defined by implementations
definition:
  v: May be used to represent additional information that is not part of the basic definition of the resource. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
comment:
  v: There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
alias:
  v: extensions
alias:
  v: user content
min:
  v: 0
max:
  v: *
base:
  path:
    v: DomainResource.extension
  min:
    v: 0
  max:
    v: *
type:
  code:
    v: Extension
    l: Extension
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
constraint:
  key:
    v: ext-1
  severity:
    v: error
  human:
    v: Must have either extensions or value[x], not both
  expression:
    v: extension.exists() != value.exists()
  xpath:
    v: exists(f:extension)!=exists(f:*[starts-with(local-name(.), "value")])
  source:
    v: http://hl7.org/fhir/StructureDefinition/Extension
    l: Extension
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: N/A

id:
  v: Subscription.modifierExtension
path:
  v: Subscription.modifierExtension
short:
  v: Extensions that cannot be ignored
definition:
  v: May be used to represent additional information that is not part of the basic definition of the resource and that modifies the understanding of the element that contains it and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer is allowed to define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).
comment:
  v: There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
requirements:
  v: Modifier extensions allow for extensions that *cannot* be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the [definition of modifier extensions](http://hl7.org/fhir/R4/extensibility.html#modifierExtension).
alias:
  v: extensions
alias:
  v: user content
min:
  v: 0
max:
  v: *
base:
  path:
    v: DomainResource.modifierExtension
  min:
    v: 0
  max:
    v: *
type:
  code:
    v: Extension
    l: Extension
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
constraint:
  key:
    v: ext-1
  severity:
    v: error
  human:
    v: Must have either extensions or value[x], not both
  expression:
    v: extension.exists() != value.exists()
  xpath:
    v: exists(f:extension)!=exists(f:*[starts-with(local-name(.), "value")])
  source:
    v: http://hl7.org/fhir/StructureDefinition/Extension
    l: Extension
is modifier:
  v: true
is modifier reason:
  v: Modifier extensions are expected to modify the meaning or interpretation of the resource that contains them
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: N/A

id:
  v: Subscription.status
path:
  v: Subscription.status
short:
  v: requested | active | error | off
definition:
  v: The status of the subscription, which marks the server state for managing the subscription.
comment:
  v: A client can only submit subscription resources in the requested or off state. Only the server can move a subscription from requested to active, and then to error. Either the server or the client can turn a subscription off. This element is labeled as a modifier because the status contains codes that mark the resource as not currently valid.
min:
  v: 1
max:
  v: 1
base:
  path:
    v: Subscription.status
  min:
    v: 1
  max:
    v: 1
type:
  code:
    v: code
    l: code
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
must support:
  v: true
is modifier:
  v: true
is modifier reason:
  v: This element is labelled as a modifier because it is a status element that contains status entered-in-error which means that the resource should not be treated as valid
is summary:
  v: true
binding:
  extension:
    url:
      v: http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName
      l: elementdefinition-bindingName
    value: String
      v: SubscriptionStatus
  strength:
    v: required
  description:
    v: The status of a subscription.
  value set:
    v: http://hl7.org/fhir/ValueSet/subscription-status|4.0.1
    l: http://hl7.org/fhir/ValueSet/subscription-status
mapping:
  identity:
    v: w5
  map:
    v: FiveWs.status

id:
  v: Subscription.contact
path:
  v: Subscription.contact
short:
  v: Contact details for source (e.g. troubleshooting)
definition:
  v: Contact details for a human to contact about the subscription. The primary use of this for system administrator troubleshooting.
min:
  v: 0
max:
  v: *
base:
  path:
    v: Subscription.contact
  min:
    v: 0
  max:
    v: *
type:
  code:
    v: ContactPoint
    l: ContactPoint
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
is modifier:
  v: false
is summary:
  v: true
mapping:
  identity:
    v: w5
  map:
    v: FiveWs.subject[x]
mapping:
  identity:
    v: w5
  map:
    v: FiveWs.subject

id:
  v: Subscription.end
path:
  v: Subscription.end
short:
  v: When to automatically delete the subscription
definition:
  v: The time for the server to turn the subscription off.
comment:
  v: The server is permitted to deviate from this time but should observe it.
min:
  v: 0
max:
  v: 1
base:
  path:
    v: Subscription.end
  min:
    v: 0
  max:
    v: 1
type:
  code:
    v: instant
    l: instant
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
is modifier:
  v: false
is summary:
  v: true
mapping:
  identity:
    v: w5
  map:
    v: FiveWs.done[x]

id:
  v: Subscription.reason
path:
  v: Subscription.reason
short:
  v: Description of why this subscription was created
definition:
  v: A description of why this subscription is defined.
min:
  v: 1
max:
  v: 1
base:
  path:
    v: Subscription.reason
  min:
    v: 1
  max:
    v: 1
type:
  code:
    v: string
    l: string
fixed: String
  v: subscriber change notifications
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
must support:
  v: true
is modifier:
  v: false
is summary:
  v: true
mapping:
  identity:
    v: w5
  map:
    v: FiveWs.why[x]

id:
  v: Subscription.criteria
path:
  v: Subscription.criteria
short:
  v: Rule for server push
definition:
  v: The rules that the server should use to determine when to generate notifications for this subscription.
comment:
  v: The rules are search criteria (without the [base] part). Like Bundle.entry.request.url, it has no leading "/".
min:
  v: 1
max:
  v: 1
base:
  path:
    v: Subscription.criteria
  min:
    v: 1
  max:
    v: 1
type:
  code:
    v: string
    l: string
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
must support:
  v: true
is modifier:
  v: false
is summary:
  v: true

id:
  v: Subscription.error
path:
  v: Subscription.error
short:
  v: Latest error note
definition:
  v: A record of the last error that occurred when the server processed a notification.
min:
  v: 0
max:
  v: 1
base:
  path:
    v: Subscription.error
  min:
    v: 0
  max:
    v: 1
type:
  code:
    v: string
    l: string
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
is modifier:
  v: false
is summary:
  v: true

id:
  v: Subscription.channel
path:
  v: Subscription.channel
short:
  v: The channel on which to report matches to the criteria
definition:
  v: Details where to send notifications when resources are received that meet the criteria.
min:
  v: 1
max:
  v: 1
base:
  path:
    v: Subscription.channel
  min:
    v: 1
  max:
    v: 1
type:
  code:
    v: BackboneElement
    l: BackboneElement
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
is modifier:
  v: false
is summary:
  v: true

id:
  v: Subscription.channel.id
path:
  v: Subscription.channel.id
representation:
  v: xmlAttr
short:
  v: Unique id for inter-element referencing
definition:
  v: Unique id for the element within a resource (for internal references). This may be any string value that does not contain spaces.
min:
  v: 0
max:
  v: 1
base:
  path:
    v: Element.id
  min:
    v: 0
  max:
    v: 1
type:
  extension:
    url:
      v: http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type
      l: structuredefinition-fhir-type
    value: Url
      v: string
      l: string
  code:
    v: http://hl7.org/fhirpath/System.String
    l: System.String
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: n/a

id:
  v: Subscription.channel.extension
path:
  v: Subscription.channel.extension
short:
  v: Additional content defined by implementations
definition:
  v: May be used to represent additional information that is not part of the basic definition of the element. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension.
comment:
  v: There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
alias:
  v: extensions
alias:
  v: user content
min:
  v: 0
max:
  v: *
base:
  path:
    v: Element.extension
  min:
    v: 0
  max:
    v: *
type:
  code:
    v: Extension
    l: Extension
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
constraint:
  key:
    v: ext-1
  severity:
    v: error
  human:
    v: Must have either extensions or value[x], not both
  expression:
    v: extension.exists() != value.exists()
  xpath:
    v: exists(f:extension)!=exists(f:*[starts-with(local-name(.), "value")])
  source:
    v: http://hl7.org/fhir/StructureDefinition/Extension
    l: Extension
is modifier:
  v: false
is summary:
  v: false
mapping:
  identity:
    v: rim
  map:
    v: n/a

id:
  v: Subscription.channel.modifierExtension
path:
  v: Subscription.channel.modifierExtension
short:
  v: Extensions that cannot be ignored even if unrecognized
definition:
  v: May be used to represent additional information that is not part of the basic definition of the element and that modifies the understanding of the element in which it is contained and/or the understanding of the containing element's descendants. Usually modifier elements provide negation or qualification. To make the use of extensions safe and manageable, there is a strict set of governance applied to the definition and use of extensions. Though any implementer can define an extension, there is a set of requirements that SHALL be met as part of the definition of the extension. Applications processing a resource are required to check for modifier extensions. Modifier extensions SHALL NOT change the meaning of any elements on Resource or DomainResource (including cannot change the meaning of modifierExtension itself).
comment:
  v: There can be no stigma associated with the use of extensions by any application, project, or standard - regardless of the institution or jurisdiction that uses or defines the extensions. The use of extensions is what allows the FHIR specification to retain a core level of simplicity for everyone.
requirements:
  v: Modifier extensions allow for extensions that *cannot* be safely ignored to be clearly distinguished from the vast majority of extensions which can be safely ignored. This promotes interoperability by eliminating the need for implementers to prohibit the presence of extensions. For further information, see the [definition of modifier extensions](http://hl7.org/fhir/R4/extensibility.html#modifierExtension).
alias:
  v: extensions
alias:
  v: user content
alias:
  v: modifiers
min:
  v: 0
max:
  v: *
base:
  path:
    v: BackboneElement.modifierExtension
  min:
    v: 0
  max:
    v: *
type:
  code:
    v: Extension
    l: Extension
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
constraint:
  key:
    v: ext-1
  severity:
    v: error
  human:
    v: Must have either extensions or value[x], not both
  expression:
    v: extension.exists() != value.exists()
  xpath:
    v: exists(f:extension)!=exists(f:*[starts-with(local-name(.), "value")])
  source:
    v: http://hl7.org/fhir/StructureDefinition/Extension
    l: Extension
is modifier:
  v: true
is modifier reason:
  v: Modifier extensions are expected to modify the meaning or interpretation of the element that contains them
is summary:
  v: true
mapping:
  identity:
    v: rim
  map:
    v: N/A

id:
  v: Subscription.channel.type
path:
  v: Subscription.channel.type
short:
  v: rest-hook | websocket | email | sms | message
definition:
  v: The type of channel to send notifications on.
min:
  v: 1
max:
  v: 1
base:
  path:
    v: Subscription.channel.type
  min:
    v: 1
  max:
    v: 1
type:
  code:
    v: code
    l: code
fixed: Code
  v: rest-hook
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
must support:
  v: true
is modifier:
  v: false
is summary:
  v: true
binding:
  extension:
    url:
      v: http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName
      l: elementdefinition-bindingName
    value: String
      v: SubscriptionChannelType
  strength:
    v: required
  description:
    v: The type of method used to execute a subscription.
  value set:
    v: http://hl7.org/fhir/ValueSet/subscription-channel-type|4.0.1
    l: http://hl7.org/fhir/ValueSet/subscription-channel-type

id:
  v: Subscription.channel.endpoint
path:
  v: Subscription.channel.endpoint
short:
  v: Where the channel points to
definition:
  v: The url that describes the actual end-point to send messages to.
comment:
  v: For rest-hook, and websocket, the end-point must be an http: or https: URL; for email, a mailto: url, for sms, a tel: url, and for message the endpoint can be in any form of url the server understands (usually, http: or mllp:). The URI is allowed to be relative; in which case, it is relative to the server end-point (since there may be more than one, clients should avoid using relative URIs).
min:
  v: 0
max:
  v: 1
base:
  path:
    v: Subscription.channel.endpoint
  min:
    v: 0
  max:
    v: 1
type:
  code:
    v: url
    l: url
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
must support:
  v: true
is modifier:
  v: false
is summary:
  v: true

id:
  v: Subscription.channel.payload
path:
  v: Subscription.channel.payload
short:
  v: MIME type to send, or omit for no payload
definition:
  v: The mime type to send the payload in - either application/fhir+xml, or application/fhir+json. If the payload is not present, then there is no payload in the notification, just a notification. The mime type "text/plain" may also be used for Email and SMS subscriptions.
comment:
  v: Sending the payload has obvious security implications. The server is responsible for ensuring that the content is appropriately secured.
min:
  v: 0
max:
  v: 0
base:
  path:
    v: Subscription.channel.payload
  min:
    v: 0
  max:
    v: 1
type:
  code:
    v: code
    l: code
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
is modifier:
  v: false
is summary:
  v: true
binding:
  extension:
    url:
      v: http://hl7.org/fhir/StructureDefinition/elementdefinition-bindingName
      l: elementdefinition-bindingName
    value: String
      v: MimeType
  strength:
    v: required
  description:
    v: The mime type of an attachment. Any valid mime type is allowed.
  value set:
    v: http://hl7.org/fhir/ValueSet/mimetypes|4.0.1
    l: http://hl7.org/fhir/ValueSet/mimetypes

id:
  v: Subscription.channel.header
path:
  v: Subscription.channel.header
short:
  v: Usage depends on the channel type
definition:
  v: Additional headers / information to send as part of the notification.
comment:
  v: Exactly what these mean depend on the channel type. They can convey additional information to the recipient and/or meet security requirements; for example, support of multiple headers in the outgoing notifications for rest-hook type subscriptions.
min:
  v: 0
max:
  v: *
base:
  path:
    v: Subscription.channel.header
  min:
    v: 0
  max:
    v: *
type:
  code:
    v: string
    l: string
constraint:
  key:
    v: ele-1
  severity:
    v: error
  human:
    v: All FHIR elements must have a @value or children
  expression:
    v: hasValue() or (children().count() > id.count())
  xpath:
    v: @value|f:*|h:div
  source:
    v: http://hl7.org/fhir/StructureDefinition/Element
    l: Element
must support:
  v: true
is modifier:
  v: false
is summary:
  v: true

element:
  id:
    v: Subscription
  path:
    v: Subscription
element:
  id:
    v: Subscription.status
  path:
    v: Subscription.status
  must support:
    v: true
element:
  id:
    v: Subscription.reason
  path:
    v: Subscription.reason
  fixed: String
    v: subscriber change notifications
  must support:
    v: true
element:
  id:
    v: Subscription.criteria
  path:
    v: Subscription.criteria
  must support:
    v: true
element:
  id:
    v: Subscription.channel.type
  path:
    v: Subscription.channel.type
  fixed: Code
    v: rest-hook
  must support:
    v: true
element:
  id:
    v: Subscription.channel.endpoint
  path:
    v: Subscription.channel.endpoint
  must support:
    v: true
element:
  id:
    v: Subscription.channel.payload
  path:
    v: Subscription.channel.payload
  max:
    v: 0
element:
  id:
    v: Subscription.channel.header
  path:
    v: Subscription.channel.header
  must support:
    v: true