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@@ -1127,10 +1127,89 @@ Invoker</a> acts natively is an adapter for Spring Cloud Function jars.</p>
<p>The <a href="https://aws.amazon.com/">AWS</a> adapter takes a Spring Cloud Function app and converts it to a form that can run in AWS Lambda.</p>
</div>
<div class="paragraph">
<p>The adapter has a couple of generic request handlers that you can use. The most generic is <code>SpringBootStreamHandler</code>, which uses a Jackson <code>ObjectMapper</code> provided by Spring Boot to serialize and deserialize the objects in the function. There is also a <code>SpringBootRequestHandler</code> which you can extend, and provide the input and output types as type parameters (enabling AWS to inspect the class and do the JSON conversions itself).</p>
<p>The details of how to get stared with AWS Lambda is out of scope of this document, so the expectation is that user has some familiarity with
AWS and AWS Lambda and wants to learn what additional value spring provides.</p>
</div>
<div class="sect3">
<h4 id="_getting_started_2"><a class="link" href="#_getting_started_2">Getting Started</a></h4>
<div class="paragraph">
<p>One of the goals of Spring Cloud Function framework is to provide necessary infrastructure elements to enable a <em>simple function application</em>
to interact in a certain way in a particular environment.
A simple function application (in context or Spring) is an application that contains beans of type Supplier, Function or Consumer.
So, with AWS it means that a simple function bean should somehow be recognised and executed in AWS Lambda environment.</p>
</div>
<div class="paragraph">
<p>If your app has more than one <code>@Bean</code> of type <code>Function</code> etc. then you can choose the one to use by configuring <code>function.name</code> (e.g. as <code>FUNCTION_NAME</code> environment variable in AWS). The functions are extracted from the Spring Cloud <code>FunctionCatalog</code> (searching first for <code>Function</code> then <code>Consumer</code> and finally <code>Supplier</code>).</p>
<p>Let’s look at the example:</p>
</div>
<div class="listingblock">
<div class="content">
<pre class="highlightjs highlight"><code class="language-java hljs" data-lang="java">@SpringBootApplication
public class FunctionConfiguration {
public static void main(String[] args) {
SpringApplication.run(FunctionConfiguration.class, args);
}
@Bean
public Function&lt;String, String&gt; uppercase() {
return value -&gt; value.toUpperCase();
}
}</code></pre>
</div>
</div>
<div class="paragraph">
<p>It shows a complete Spring Boot application with a function bean defined in it. What’s interesting is that on the surface this is just
another boot app, but in the context of AWS Adapter it is also a perfectly valid AWS Lambda application. No other code or configuration
is required. All you need to do is package it and deploy it, so let’s look how we can do that.</p>
</div>
<div class="paragraph">
<p>To make things simpler we’ve provided a sample project ready to be built and deployed and you can access it
<a href="https://github.com/spring-cloud/spring-cloud-function/tree/master/spring-cloud-function-samples/function-sample-aws">here</a>.</p>
</div>
<div class="paragraph">
<p>You simply execute <code>./mvnw clean package</code> to generate JAR file. All the necessary maven plugins have already been setup to generate
appropriate AWS deployable JAR file. (You can read more details about JAR layout in <a href="#_notes_on_jar_layout">Notes on JAR Layout</a>).</p>
</div>
<div class="paragraph">
<p>Then you have to upload the JAR file (via AWS dashboard or AWS CLI) to AWS.</p>
</div>
<div class="paragraph">
<p>When ask about <em>handler</em> you specify <code>org.springframework.cloud.function.adapter.aws.FunctionInvoker::handleRequest</code> which is a generic request handler.</p>
</div>
<div class="imageblock text-center">
<div class="content">
<img src="https://raw.githubusercontent.com/spring-cloud/spring-cloud-function/master/docs/src/main/asciidoc/images/AWS-deploy.png" alt="AWS deploy" width="800">
</div>
</div>
<div class="paragraph">
<p>That is all. Save and execute the function with some sample data which for this function is expected to be a
String which function will uppercase and return back.</p>
</div>
<div class="paragraph">
<p>While <code>org.springframework.cloud.function.adapter.aws.FunctionInvoker</code> is a general purpose AWS&#8217;s <code>RequestHandler</code> implementation aimed at completely
isolating you from the specifics of AWS Lambda API, for some cases you may want to specify which specific AWS&#8217;s <code>RequestHandler</code> you want
to use. The next section will explain you how you can accomplish just that.</p>
</div>
</div>
<div class="sect3">
<h4 id="_aws_request_handlers"><a class="link" href="#_aws_request_handlers">AWS Request Handlers</a></h4>
<div class="paragraph">
<p>The adapter has a couple of generic request handlers that you can use. The most generic is (and the one we used in the Getting Started section)
is <code>org.springframework.cloud.function.adapter.aws.FunctionInvoke</code> which is the implementation of AWS&#8217;s <code>RequestStreamHandler</code>.
User doesn&#8217;t need to do anything other then specify it as 'handler' on AWS dashborad when deplioyimng function.
It will handle most of the case including Kinesis, streaming etc. .</p>
</div>
<div class="paragraph">
<p>The most generic is
<code>SpringBootStreamHandler</code>, which uses a Jackson <code>ObjectMapper</code> provided by Spring Boot to serialize and deserialize the objects
in the function. There is also a <code>SpringBootRequestHandler</code> which you can extend, and provide the input and output types as type
parameters (enabling AWS to inspect the class and do the JSON conversions itself).</p>
</div>
<div class="paragraph">
<p>If your app has more than one <code>@Bean</code> of type <code>Function</code> etc. then you can choose the one to use by configuring <code>function.name</code>
(e.g. as <code>FUNCTION_NAME</code> environment variable in AWS). The functions are extracted from the Spring Cloud <code>FunctionCatalog</code>
(searching first for <code>Function</code> then <code>Consumer</code> and finally <code>Supplier</code>).</p>
</div>
</div>
<div class="sect3">
<h4 id="_notes_on_jar_layout"><a class="link" href="#_notes_on_jar_layout">Notes on JAR Layout</a></h4>