Transactions

Next to the normal individual CRUD operations, the FhirClient has the ability to send transactions to a FHIR server. You can use transactions by calling the Transaction(Bundle transaction) function of the FhirClient. This functions requires a transaction bundle as input parameter that describes the transaction the server has to carry out. The easiest way to create a transaction bundle is by using TransactionBuilder.

Using TransactionBuilder

TransactionBuilder is a function to easily create a Bundle resource to describe a transaction or a batch, instead of creating a Bundle and adding all the entries manually. Simple interactions can be done by just calling the corresponding function of the builder e.g. (Create(), Update(), Read(), Delete() etc. ). After you have added all your instructions all you need to do is call the ToBundle() function. This will return the transaction Bundle that you’ve just created, which you can then pass to the Transaction() function of the FhirClient.

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 witd 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 is the list of all interactions you can add to the transaction bundle using the TransactionBuilder :

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

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

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

• Delete(): Deletes a resources on the server.

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

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

• CapabilityStatement(): Returns the CapabilityStatement of the server.

• ResourceHistory(): Returns all known historical versions of the resource from the server.

• CollectionHistory(): Returns all known historical versions of resources of a specific type from the server.

• ServerHistory(): Returns all known historical versions of all resources from the server.

• Transaction(): Call a sub-transaction on the server.

Conditional interactions

Next to the ‘standard’ interactions, TransactionBuilder also allows you to add the conditional interactions specified by the FHIR specification. The conditional interactions can be added by using the optional SearchParam parameter that some of the standard interactions have. You can use SearchParam to specify the conditions you want.

See the example below:

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);

Below is the list of functions that support conditional interactions:

• Create()

• Update()

• Delete()

• Patch()