Merge pull request #81 from srdc/add-fhir-client-util

Add FhirClientUtil for creating OnFhirNetworkClient with configurable security settings

onfhir-client/src/main/scala/io/onfhir/client/model/FhirRepositorySecuritySettings.scala

@@ -0,0 +1,36 @@
+package io.onfhir.client.model
+
+/**
+ * Interface for security settings
+ */
+trait IFhirRepositorySecuritySettings
+
+/**
+ * Security settings for FHIR API access via bearer token
+ *
+ * @param clientId                   OpenID Client identifier assigned to toFhir
+ * @param clientSecret               OpenID Client secret given to toFhir
+ * @param requiredScopes             List of required scores to write the resources
+ * @param authzServerTokenEndpoint   Authorization servers token endpoint
+ * @param clientAuthenticationMethod Client authentication method
+ */
+case class BearerTokenAuthorizationSettings(clientId: String,
+                                            clientSecret: String,
+                                            requiredScopes: Seq[String],
+                                            authzServerTokenEndpoint: String,
+                                            clientAuthenticationMethod: String = "client_secret_basic") extends IFhirRepositorySecuritySettings
+
+/**
+ * Security settings for FHIR API access via basic authentication
+ *
+ * @param username Username for basic authentication
+ * @param password Password for basic authentication
+ */
+case class BasicAuthenticationSettings(username: String, password: String) extends IFhirRepositorySecuritySettings
+
+/**
+ * Security settings for FHIR API access via fixed token
+ *
+ * @param token The fixed token
+ */
+case class FixedTokenAuthenticationSettings(token: String) extends IFhirRepositorySecuritySettings

onfhir-client/src/main/scala/io/onfhir/client/util/FhirClientUtil.scala

@@ -0,0 +1,46 @@
+package io.onfhir.client.util
+
+import akka.actor.ActorSystem
+import io.onfhir.client.OnFhirNetworkClient
+import io.onfhir.client.model.{BasicAuthenticationSettings, BearerTokenAuthorizationSettings, FixedTokenAuthenticationSettings, IFhirRepositorySecuritySettings}
+
+object FhirClientUtil {
+  /**
+   * Creates an `OnFhirNetworkClient` instance configured with optional security settings.
+   * This client is used to interact with an FHIR repository, supporting various authentication
+   * mechanisms such as bearer token, basic authentication, or fixed token authentication.
+   *
+   * @param fhirRepoUrl      The base URL of the FHIR repository that the client will communicate with.
+   * @param securitySettings An optional parameter specifying the security settings for authentication.
+   *                         These settings determine the type of authentication applied, if any.
+   *                           - `BearerTokenAuthorizationSettings` for OAuth2/OpenID Connect bearer tokens.
+   *                           - `BasicAuthenticationSettings` for basic username/password authentication.
+   *                           - `FixedTokenAuthenticationSettings` for fixed token-based authentication.
+   * @param actorSystem      The Akka ActorSystem, provided implicitly, for handling the underlying
+   *                         network operations and asynchronous behavior.
+   * @return A configured `OnFhirNetworkClient` ready for use.
+   */
+  def createOnFhirClient(fhirRepoUrl: String, securitySettings: Option[IFhirRepositorySecuritySettings] = None)
+                        (implicit actorSystem: ActorSystem): OnFhirNetworkClient = {
+    // Create a basic client with the provided FHIR repository URL.
+    val client = OnFhirNetworkClient.apply(fhirRepoUrl)
+
+    // Apply optional security settings for authentication, based on the type provided.
+    securitySettings
+      .map {
+        // Handle bearer token-based authentication (OAuth2/OpenID Connect).
+        case BearerTokenAuthorizationSettings(clientId, clientSecret, requiredScopes, authzServerTokenEndpoint, clientAuthenticationMethod) =>
+          client.withOpenIdBearerTokenAuthentication(clientId, clientSecret, requiredScopes, authzServerTokenEndpoint, clientAuthenticationMethod)
+
+        // Handle basic authentication with a username and password.
+        case BasicAuthenticationSettings(username, password) =>
+          client.withBasicAuthentication(username, password)
+
+        // Handle fixed token-based authentication.
+        case FixedTokenAuthenticationSettings(token) =>
+          client.withFixedBasicTokenAuthentication(token)
+      }
+      // If no security settings are provided, return the basic client without authentication.
+      .getOrElse(client)
+  }
+}