Integrate with AWS API Gateway.

Wip on #2721.

aws-lambda-scorer/lambda-template/build.gradle

@@ -18,6 +18,7 @@ dependencies {
  compile group: 'ai.h2o', name: 'mojo2-runtime-api', version: '0.13.7'
  compile group: 'ai.h2o', name: 'mojo2-runtime-impl', version: '0.13.7'
  compile group: 'com.amazonaws', name: 'aws-lambda-java-core', version: '1.2.0'
+ compile group: 'com.amazonaws', name: 'aws-lambda-java-events', version: '2.2.3'
  compile group: 'com.amazonaws', name: 'aws-java-sdk-s3', version: '1.11.445'
  compile group: 'com.google.code.gson', name: 'gson', version: '2.3.1'
  compile group: 'io.swagger.core.v3', name: 'swagger-annotations', version: '2.0.5'

aws-lambda-scorer/lambda-template/src/main/java/ai/h2o/dia/deploy/aws/lambda/ApiGatewayWrapper.java

@@ -0,0 +1,53 @@
+package ai.h2o.dia.deploy.aws.lambda;
+
+import ai.h2o.dai.deploy.aws.lambda.model.ScoreRequest;
+import ai.h2o.dai.deploy.aws.lambda.model.ScoreResponse;
+import ai.h2o.mojos.runtime.lic.LicenseException;
+import com.amazonaws.services.lambda.runtime.Context;
+import com.amazonaws.services.lambda.runtime.RequestHandler;
+import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyRequestEvent;
+import com.amazonaws.services.lambda.runtime.events.APIGatewayProxyResponseEvent;
+import com.google.gson.Gson;
+import com.google.gson.JsonSyntaxException;
+import org.apache.http.HttpStatus;
+
+import java.io.IOException;
+
+/**
+ * Wraps {@link MojoScorer} so that it can be called via the AWS API gateway.
+ *
+ * <p>Note that AWS API Gateway strictly mandates the input and output formats that we need to adhere to here.
+ * In addition, this class does error handling.
+ *
+ * @see <a href="https://docs.aws.amazon.com/apigateway/latest/developerguide/api-gateway-create-api-as-simple-proxy-for-lambda.html">
+ * Build an API Gateway API with Lambda Proxy Integration</a>
+ */
+public class ApiGatewayWrapper implements RequestHandler<APIGatewayProxyRequestEvent, APIGatewayProxyResponseEvent> {
+ private final Gson gson = new Gson();
+ private final MojoScorer mojoScorer = new MojoScorer();
+
+ @Override
+ public APIGatewayProxyResponseEvent handleRequest(APIGatewayProxyRequestEvent input, Context context) {
+ try {
+ ScoreRequest scoreRequest = gson.fromJson(input.getBody(), ScoreRequest.class);
+ ScoreResponse scoreResponse = mojoScorer.score(scoreRequest, context);
+ return toSuccessResponse(gson.toJson(scoreResponse));
+ } catch (JsonSyntaxException e) {
+ return toErrorResponse(HttpStatus.SC_BAD_REQUEST, e);
+ } catch (IOException e) {
+ return toErrorResponse(HttpStatus.SC_NOT_FOUND, e);
+ } catch (LicenseException e) {
+ return toErrorResponse(HttpStatus.SC_SERVICE_UNAVAILABLE, e);
+ } catch (Exception e) {
+ return toErrorResponse(HttpStatus.SC_INTERNAL_SERVER_ERROR, e);
+ }
+ }
+
+ private static APIGatewayProxyResponseEvent toErrorResponse(int statusCode, Exception exception) {
+ return new APIGatewayProxyResponseEvent().withStatusCode(statusCode).withBody(exception.toString());
+ }
+
+ private static APIGatewayProxyResponseEvent toSuccessResponse(String body) {
+ return new APIGatewayProxyResponseEvent().withStatusCode(HttpStatus.SC_OK).withBody(body);
+ }
+}

aws-lambda-scorer/terraform-recipe/api_gateway.tf

@@ -0,0 +1,52 @@
+resource "aws_api_gateway_rest_api" "scorer_api" {
+ name = "${var.lambda_id}_api"
+ description = "H2O Driverless AI Mojo Scorer API (${var.lambda_id})"
+}
+
+resource "aws_api_gateway_resource" "proxy_resource" {
+ rest_api_id = "${aws_api_gateway_rest_api.scorer_api.id}"
+ parent_id = "${aws_api_gateway_rest_api.scorer_api.root_resource_id}"
+ path_part = "score"
+}
+
+resource "aws_api_gateway_method" "proxy_method" {
+ rest_api_id = "${aws_api_gateway_rest_api.scorer_api.id}"
+ resource_id = "${aws_api_gateway_resource.proxy_resource.id}"
+ http_method = "POST"
+ authorization = "NONE"
+}
+
+resource "aws_api_gateway_integration" "scorer_integration" {
+ rest_api_id = "${aws_api_gateway_rest_api.scorer_api.id}"
+ resource_id = "${aws_api_gateway_method.proxy_method.resource_id}"
+ http_method = "${aws_api_gateway_method.proxy_method.http_method}"
+
+ integration_http_method = "POST"
+ type = "AWS_PROXY"
+ uri = "${aws_lambda_function.scorer_lambda.invoke_arn}"
+}
+
+resource "aws_api_gateway_deployment" "scorer_api_deployment" {
+ depends_on = [
+ "aws_api_gateway_integration.scorer_integration"
+ ]
+
+ rest_api_id = "${aws_api_gateway_rest_api.scorer_api.id}"
+ stage_name = "test"
+}
+
+resource "aws_lambda_permission" "apigw" {
+ statement_id = "AllowExecutionFromAPIGateway"
+ action = "lambda:InvokeFunction"
+ function_name = "${aws_lambda_function.scorer_lambda.arn}"
+ principal = "apigateway.amazonaws.com"
+
+ # The /*/*/* part allows invocation from any stage, method and resource path
+ # within API Gateway REST API.
+ source_arn = "${aws_api_gateway_rest_api.scorer_api.execution_arn}/*/*/*"
+}
+
+output "base_url" {
+ value = "${aws_api_gateway_deployment.scorer_api_deployment.invoke_url}"
+}
+

aws-lambda-scorer/terraform-recipe/main.tf

@@ -36,9 +36,9 @@ resource "aws_s3_bucket_object" "mojo" {
 // AWS Lambda function with a Java implementation of the Mojo scorer.
 resource "aws_lambda_function" "scorer_lambda" {
  function_name = "${var.lambda_id}_function"
- description = "H2O Driverless AI Mojo Scorer"
+ description = "H2O Driverless AI Mojo Scorer (${var.lambda_id})"
  filename = "${var.lambda_zip_path}"
- handler = "ai.h2o.dia.deploy.aws.lambda.MojoScorer::score"
+ handler = "ai.h2o.dia.deploy.aws.lambda.ApiGatewayWrapper::handleRequest"
  source_code_hash = "${base64sha256(file(var.lambda_zip_path))}"
  role = "${aws_iam_role.scorer_lambda_iam_role.arn}"
  runtime = "java8"