Add credit and docs for #6520 (#6542)

hapi-fhir-client-apache-http5/pom.xml

@@ -4,7 +4,7 @@
 	<parent>
 		<groupId>ca.uhn.hapi.fhir</groupId>
 		<artifactId>hapi-deployable-pom</artifactId>
-		<version>7.7.7-SNAPSHOT</version>
+		<version>7.7.10-SNAPSHOT</version>
 
 		<relativePath>../hapi-deployable-pom/pom.xml</relativePath>
 	</parent>

hapi-fhir-docs/pom.xml

@@ -129,7 +129,13 @@
 			<groupId>com.fasterxml.jackson.core</groupId>
 			<artifactId>jackson-databind</artifactId>
 		</dependency>
-    </dependencies>
+		<dependency>
+			<groupId>ca.uhn.hapi.fhir</groupId>
+			<artifactId>hapi-fhir-client-apache-http5</artifactId>
+			<version>7.7.10-SNAPSHOT</version>
+			<scope>compile</scope>
+		</dependency>
+	</dependencies>
 
 	<build>
 		<plugins>

hapi-fhir-docs/src/main/java/ca/uhn/hapi/fhir/docs/GenericClientExample.java

@@ -22,10 +22,13 @@ package ca.uhn.hapi.fhir.docs;
 import ca.uhn.fhir.context.FhirContext;
 import ca.uhn.fhir.context.PerformanceOptionsEnum;
 import ca.uhn.fhir.model.api.IResource;
+import ca.uhn.fhir.okhttp.client.OkHttpRestfulClientFactory;
 import ca.uhn.fhir.rest.api.DeleteCascadeModeEnum;
 import ca.uhn.fhir.rest.api.MethodOutcome;
 import ca.uhn.fhir.rest.api.SearchStyleEnum;
 import ca.uhn.fhir.rest.api.SummaryEnum;
+import ca.uhn.fhir.rest.client.apache.ApacheHttp5RestfulClientFactory;
+import ca.uhn.fhir.rest.client.apache.ApacheRestfulClientFactory;
 import ca.uhn.fhir.rest.client.api.IGenericClient;
 import ca.uhn.fhir.rest.client.api.ServerValidationModeEnum;
 import ca.uhn.fhir.rest.client.interceptor.LoggingInterceptor;
@@ -52,14 +55,34 @@ import java.util.ArrayList;
 import java.util.List;
 
 public class GenericClientExample {
+	public static void chooseProvider() {
+		// START SNIPPET: chooseProvider
+		// Create a context and configure it for deferred child scanning
+		FhirContext ctx = FhirContext.forR5();
+
+		// Use Apache HttpClient 4.x client (this is the default)
+		ctx.setRestfulClientFactory(new ApacheRestfulClientFactory(ctx));
+
+		// Use OkHttp as the HTTP provider
+		ctx.setRestfulClientFactory(new OkHttpRestfulClientFactory(ctx));
+
+		// Use Apache HttpClient 5.x client
+		ctx.setRestfulClientFactory(new ApacheHttp5RestfulClientFactory(ctx));
+
+		// Now create a client and use it
+		String serverBase = "http://hapi.fhir.org/baseR5";
+		IGenericClient client = ctx.newRestfulGenericClient(serverBase);
+		// END SNIPPET: chooseProvider
+	}
+
 	public static void deferModelScanning() {
 		// START SNIPPET: deferModelScanning
 		// Create a context and configure it for deferred child scanning
-		FhirContext ctx = FhirContext.forDstu2();
+		FhirContext ctx = FhirContext.forR5();
 		ctx.setPerformanceOptions(PerformanceOptionsEnum.DEFERRED_MODEL_SCANNING);
 
 		// Now create a client and use it
-		String serverBase = "http://fhirtest.uhn.ca/baseDstu2";
+		String serverBase = "http://hapi.fhir.org/baseR5";
 		IGenericClient client = ctx.newRestfulGenericClient(serverBase);
 		// END SNIPPET: deferModelScanning
 	}
@@ -67,13 +90,13 @@ public class GenericClientExample {
 	public static void performance() {
 		// START SNIPPET: dontValidate
 		// Create a context
-		FhirContext ctx = FhirContext.forDstu2();
+		FhirContext ctx = FhirContext.forR5();
 
 		// Disable server validation (don't pull the server's metadata first)
 		ctx.getRestfulClientFactory().setServerValidationMode(ServerValidationModeEnum.NEVER);
 
 		// Now create a client and use it
-		String serverBase = "http://fhirtest.uhn.ca/baseDstu2";
+		String serverBase = "http://hapi.fhir.org/baseR5";
 		IGenericClient client = ctx.newRestfulGenericClient(serverBase);
 		// END SNIPPET: dontValidate
 	}
@@ -134,8 +157,8 @@ public class GenericClientExample {
 	public static void simpleExample() {
 		// START SNIPPET: simple
 		// We're connecting to a DSTU1 compliant server in this example
-		FhirContext ctx = FhirContext.forDstu2();
+		FhirContext ctx = FhirContext.forR5();
-		String serverBase = "http://fhirtest.uhn.ca/baseDstu2";
+		String serverBase = "http://hapi.fhir.org/baseR5";
 
 		IGenericClient client = ctx.newRestfulGenericClient(serverBase);
 

hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/changelog/7_8_0/6520-add-httpclient5-support.yaml

@@ -0,0 +1,8 @@
+---
+type: add
+issue: 6520
+title: "A new FHIR client implementation based on Apache HttpClient 5.x has been
+  added to HAPI FHIR. This implementation is optional for now, with the default
+  remaining to use HttpClient 4.x, but this will likely become the default (and only
+  supported version of the HttpClient library) in the future. Thanks to 
+  Ibrahim Tallouzi for the contribution!"

hapi-fhir-docs/src/main/resources/ca/uhn/hapi/fhir/docs/client/introduction.md

@@ -11,3 +11,11 @@ There are two types of REST clients provided by HAPI:
 * The [Annotation Client](./annotation_client.html) client relies on static binding to specific operations to give better compile-time checking against servers with a specific set of capabilities
 exposed. This second model takes more effort to use, but can be useful if the person defining the specific methods to invoke is not the same person who is using those methods.
 
+# HTTP Providers
+
+The HAPI FHIR Client framework uses an underlying HTTP provider to handle the transport communication. Most of the documentation in this section describes how to perform FHIR REST operations using the client, but you may need to select a specific provider if you need to customize the transport in any way. The following example shows how to choose from several providers.
+
+```java
+{{snippet:classpath:/ca/uhn/hapi/fhir/docs/GenericClientExample.java|chooseProvider}}
+```
+

pom.xml

@@ -956,7 +956,7 @@
 		</developer>
 		<developer>
 			<id>iyt-trifork</id>
-			<name>Ibrahim</name>
+			<name>Ibrahim Tallouzi</name>
 			<organization>Trifork A/S</organization>
 		</developer>
 	</developers>