Instance profile credentials example. (#3401)

* Instance profile credentials example.

* InstanceProfile CloudFormation template included to provision AWS
environment.

* Included java package installation under Yaml script.

* Using SpringApplication reference to prepare application context.

* Introducing SpringCloudS3Service to handle all S3 operations.

spring-cloud/spring-cloud-aws/README.md

@@ -19,3 +19,8 @@ to write the following in `application.properties`:
 cloud.aws.rds.spring-cloud-test-db
 cloud.aws.rds.spring-cloud-test-db.password=se3retpass
 ```
+Multiple application classes are available under this project. To launch InstanceProfileAwsApplication application, replace `start-class` under `pom.xml`:
+
+```
+<start-class>com.baeldung.spring.cloud.aws.InstanceProfileAwsApplication</start-class>
+```

spring-cloud/spring-cloud-aws/pom.xml

@@ -19,6 +19,7 @@
     </parent>
 
     <properties>
+        <start-class>com.baeldung.spring.cloud.aws.SpringCloudAwsApplication</start-class>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
         <java.version>1.8</java.version>

spring-cloud/spring-cloud-aws/src/main/java/com/baeldung/spring/cloud/aws/InstanceProfileAwsApplication.java

@@ -0,0 +1,60 @@
+package com.baeldung.spring.cloud.aws;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.UUID;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
+import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.context.ConfigurableApplicationContext;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+
+import com.baeldung.spring.cloud.aws.s3.SpringCloudS3Service;
+
+@Configuration
+@EnableAutoConfiguration
+@ComponentScan("com.baeldung.spring.cloud.aws.s3")
+public class InstanceProfileAwsApplication {
+
+    private static final Logger logger = LoggerFactory.getLogger(InstanceProfileAwsApplication.class);
+    private static final String applicationConfig = "spring.config.name:application-instance-profile";
+
+    private static String bucketName;
+    private static String fileName = "sample-file.txt";
+
+    private static void setupResources() {
+        bucketName = "baeldung-test-" + UUID.randomUUID()
+            .toString();
+        try {
+            Files.write(Paths.get(fileName), "Hello World!".getBytes());
+        } catch (IOException e) {
+            logger.error(e.getMessage(), e);
+        }
+    }
+
+    public static void main(String[] args) {
+        setupResources();
+        if (!new File(fileName).exists()) {
+            logger.warn("Not able to create {} file. Check your folder permissions.", fileName);
+            System.exit(1);
+        }
+
+        SpringApplication application = new SpringApplicationBuilder(InstanceProfileAwsApplication.class).properties(applicationConfig)
+            .build();
+        ConfigurableApplicationContext context = application.run(args);
+        SpringCloudS3Service service = context.getBean(SpringCloudS3Service.class);
+
+        // S3 bucket operations
+        service.createBucket(bucketName);
+        service.uploadObject(bucketName, fileName);
+        service.downloadObject(bucketName, fileName);
+        service.deleteBucket(bucketName);
+    }
+
+}

spring-cloud/spring-cloud-aws/src/main/java/com/baeldung/spring/cloud/aws/s3/SpringCloudS3Service.java

@@ -0,0 +1,64 @@
+package com.baeldung.spring.cloud.aws.s3;
+
+import java.io.File;
+import java.io.IOException;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+
+import com.amazonaws.services.s3.AmazonS3;
+import com.amazonaws.services.s3.model.ListObjectsV2Result;
+import com.amazonaws.services.s3.model.S3ObjectSummary;
+
+@Component
+public class SpringCloudS3Service {
+
+    private static final Logger logger = LoggerFactory.getLogger(SpringCloudS3Service.class);
+
+    @Autowired
+    AmazonS3 amazonS3;
+
+    @Autowired
+    SpringCloudS3 springCloudS3;
+
+    public void createBucket(String bucketName) {
+        logger.debug("Creating S3 bucket: {}", bucketName);
+        amazonS3.createBucket(bucketName);
+        logger.info("{} bucket created successfully", bucketName);
+    }
+
+    public void downloadObject(String bucketName, String objectName) {
+        String s3Url = "s3://" + bucketName + "/" + objectName;
+        try {
+            springCloudS3.downloadS3Object(s3Url);
+            logger.info("{} file download result: {}", objectName, new File(objectName).exists());
+        } catch (IOException e) {
+            logger.error(e.getMessage(), e);
+        }
+    }
+
+    public void uploadObject(String bucketName, String objectName) {
+        String s3Url = "s3://" + bucketName + "/" + objectName;
+        File file = new File(objectName);
+        try {
+            springCloudS3.uploadFileToS3(file, s3Url);
+            logger.info("{} file uploaded to S3", objectName);
+        } catch (IOException e) {
+            logger.error(e.getMessage(), e);
+        }
+    }
+
+    public void deleteBucket(String bucketName) {
+        logger.trace("Deleting S3 objects under {} bucket...", bucketName);
+        ListObjectsV2Result listObjectsV2Result = amazonS3.listObjectsV2(bucketName);
+        for (S3ObjectSummary objectSummary : listObjectsV2Result.getObjectSummaries()) {
+            logger.info("Deleting S3 object: {}", objectSummary.getKey());
+            amazonS3.deleteObject(bucketName, objectSummary.getKey());
+        }
+        logger.info("Deleting S3 bucket: {}", bucketName);
+        amazonS3.deleteBucket(bucketName);
+    }
+
+}

spring-cloud/spring-cloud-aws/src/main/resources/InstanceProfileFormation.yaml

@@ -0,0 +1,78 @@
+AWSTemplateFormatVersion: 2010-09-09
+Metadata:
+  'AWS::CloudFormation::Designer':
+    157e7d5f-5cb3-4a23-a50c-97e7f6c57173:
+      size:
+        width: 60
+        height: 60
+      position:
+        x: 450
+        'y': 90
+      z: 0
+      embeds: []
+    9bbaaa55-9cba-4555-a7c6-fb6ac248fd3a:
+      size:
+        width: 60
+        height: 60
+      position:
+        x: 260
+        'y': 90
+      z: 0
+      embeds: []
+      isassociatedwith:
+        - 157e7d5f-5cb3-4a23-a50c-97e7f6c57173
+    a7348729-a594-4dca-9b0a-e1c8d777dc3b:
+      size:
+        width: 60
+        height: 60
+      position:
+        x: 70
+        'y': 90
+      z: 0
+      embeds: []
+Resources:
+  IAMRoleBaeldung:
+    Type: 'AWS::IAM::Role'
+    Properties:
+      AssumeRolePolicyDocument:
+        Version: 2012-10-17
+        Statement:
+          - Effect: Allow
+            Principal:
+              Service:
+                - ec2.amazonaws.com
+            Action:
+              - 'sts:AssumeRole'
+      ManagedPolicyArns:
+        - 'arn:aws:iam::aws:policy/AmazonS3FullAccess'
+    Metadata:
+      'AWS::CloudFormation::Designer':
+        id: 157e7d5f-5cb3-4a23-a50c-97e7f6c57173
+  InstanceProfileBaeldung:
+    Type: 'AWS::IAM::InstanceProfile'
+    Properties:
+      Roles:
+        - !Ref IAMRoleBaeldung
+    Metadata:
+      'AWS::CloudFormation::Designer':
+        id: 9bbaaa55-9cba-4555-a7c6-fb6ac248fd3a
+  EC2Instance:
+    Type: 'AWS::EC2::Instance'
+    Properties:
+      ImageId: ami-2581aa40
+      InstanceType: t2.micro
+      IamInstanceProfile: !Ref InstanceProfileBaeldung
+      KeyName: Satish-Ohio
+      UserData: !Base64 
+        'Fn::Join':
+          - ''
+          - - |
+              #!/bin/bash
+            - |
+              apt -y install openjdk-8-jre-headless
+    Metadata:
+      'AWS::CloudFormation::Designer':
+        id: a7348729-a594-4dca-9b0a-e1c8d777dc3b
+    DependsOn:
+      - InstanceProfileBaeldung
+

spring-cloud/spring-cloud-aws/src/main/resources/application-instance-profile.properties

@@ -0,0 +1,14 @@
+# Don't try to create DataSouce when running tests which don't need a DataSource
+spring.autoconfigure.exclude=\
+  org.springframework.cloud.aws.autoconfigure.jdbc.AmazonRdsDatabaseAutoConfiguration,\
+  org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration
+cloud.aws.region.auto=true
+
+# Load instance profile credentials
+cloud.aws.credentials.instanceProfile=true
+
+# Disable auto cloud formation
+cloud.aws.stack.auto=false
+
+# Disable web environment
+spring.main.web-environment=false