Transactions

In addition to individual CRUD operations, the FhirClient can submit transaction bundles to a FHIR server. Use TransactionAsync(Bundle transaction) to send a transaction; the call requires a transaction Bundle that describes the set of operations the server should perform. The simplest way to construct such a bundle is with the TransactionBuilder helper.

Using TransactionBuilder

TransactionBuilder provides a convenient API to build a transaction or batch Bundle without manually constructing the Bundle and its entries. You can add interactions by calling the corresponding builder methods (for example Create(), Update(), Read(), Delete()). When you’ve added all entries, call ToBundle() to obtain the Bundle to pass to TransactionAsync().

var pat = new Patient() { /* set up data */ };
var client = new FhirClient("http://server.fire.ly");
var builder = new TransactionBuilder("http://server.fire.ly", Bundle.BundleType.Transaction); // or Batch

// Add a new entry to the bundle including the patient resource that needs to be created.
builder.Create(pat);

// Add a new entry to the bundle with instructions that Patient with id "1337" needs to be deleted.
builder.Delete("Patient", "1337");

// returns the transaction bundle
var bundle = builder.ToBundle();

// Send the transaction to the server.
var response = await client.TransactionAsync(bundle);

Below are the interactions you can add to a transaction bundle using TransactionBuilder:

• Create(): create a resource on the server.

• Read(): return a resource from the server.

• Update(): update a resource on the server.

• Delete(): delete a resource on the server.

• Patch(): patch a resource on the server.

• Search(): search for resources on the server using search criteria.

• CapabilityStatement(): request the server’s CapabilityStatement.

• ResourceHistory(): request the historical versions of a specific resource.

• CollectionHistory(): request historical versions of all resources of a given type.

• ServerHistory(): request server-wide historical versions of resources.

• Transaction(): execute a nested transaction on the server.

Conditional interactions

In addition to the standard interactions, TransactionBuilder supports the conditional interactions defined by the FHIR specification. Several builder methods accept an optional SearchParams parameter to express the condition to use for the interaction. Example:

var pat = new Patient() { /* set up data */ };
var client = new FhirClient("http://server.fire.ly");
var builder = new TransactionBuilder("http://server.fire.ly", Bundle.BundleType.Transaction);

// Update the patient resource with family name "Levin", and date of birth "01-01-1990"
var updateConditions = new SearchParams();
updateConditions.Add("birthdate", "1990-01-01");
updateConditions.Add("family", "Levin");
builder.Update(updateConditions, pat);

// Delete the patient with email address "test@example.org"
var deleteCondition = new SearchParams("email", "test@example.com");
builder.Delete("Patient", deleteCondition);

// returns the transaction bundle
var bundle = builder.ToBundle();

// Send the transaction to the server.
var response = await client.TransactionAsync(bundle);

The following builder methods support conditional interactions:

• Create()

• Update()

• Delete()

• Patch()