The subscription resource is used to define a push-based subscription from describes a server particular client's request 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 be notified about a message on the defined "channel" so that another system can take an appropriate action. SubscriptionTopic.

A formal identifier that is used to identify this code system when it is represented in other formats, or referenced in a specification, model, design or an instance.

A natural language name identifying the subscription.

The status of the subscription, which marks the server state for managing the subscription.

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.

The reference to the subscription topic to be notified about.

Contact details for a human to contact about the subscription. The primary use of this for system administrator troubleshooting.

The time for the server to turn the subscription off.

The server is permitted to deviate from this time but should observe it.

A description of why this subscription is defined.

The rules that filter properties to be applied to narrow the server should use subscription topic stream. When multiple filters are applied, evaluates to determine when true if all the conditions are met; otherwise it returns false. (i.e., logical AND).

If the element is a reference to generate notifications for another resource, this subscription. element contains "Reference", and the targetProfile element defines what resources can be referenced. The targetProfile may be a reference to the general definition of a resource (e.g. http://hl7.org/fhir/StructureDefinition/Patient).

The rules are search criteria (without filter label (=key) as defined in the [base] part). Like Bundle.entry.request.url, it has no leading "/". SubscriptionTopic.canfilterBy.searchParamName element.

A record of The operator to apply to the last error that occurred filter value when the server processed a notification. determining matches (Search modifiers).

Details where to send notifications when resources are received that meet the criteria. The literal value or resource path as is legal in search - for example, "Patient/123" or "le1950".

The type of channel to send notifications on.

The url that describes the actual end-point to send messages to.

For rest-hook, and websocket, rest-hook the end-point must be an http: or https: URL; for websocket ws: or wss:; for email, a mailto: url, for sms, a tel: url, url; and for message the endpoint can be in any form of url the server understands (usually, http: http/s: 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).

The mime type Additional headers / information to send as part of the payload notification.

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 - either application/fhir+xml, or application/fhir+json. If the payload outgoing notifications for rest-hook type subscriptions.

If present, a 'hearbeat" notification (keepalive) is sent via this channel with an the interval period equal to this elements integer value in seconds. If not present, then there a heartbeat notification is no payload in not sent.

If present, the notification, just maximum amount of time a notification. server will allow before failing a notification attempt.

The mime type to send the payload in - either application/fhir+xml, or application/fhir+json. The MIME types "text/plain" and "text/html" may also be used for Email and SMS subscriptions.

How much of the resource content to deliver in the notification payload. The choices are an empty payload, only the resource id, or the full resource content.

Sending the payload has obvious security implications. The server is responsible for ensuring that the content is appropriately secured.

Additional headers / information If present, where to send as part place URLs of the notification. resources in notifications.

Exactly what these mean depend on the channel type. They can convey additional information to If present, the recipient and/or meet security requirements; for example, support maximum number of multiple headers triggering resources that will be included in a notification bundle (e.g., a server will not include more than this number of trigger resources in a single notification). Note that this is not a strict limit on the outgoing notifications for rest-hook type subscriptions. number of entries in a bundle, as dependent resources can be included.