AWS Maven Wagon

This project is a Maven Wagon for Amazon S3.

It is a fork of the original Spring Build project, adapted to support session tokens.

In order to publish artifacts to an S3 bucket, the user (as identified by their access key) must be listed as an owner on the bucket.

Usage

To publish Maven artifacts to S3 a build extension must be defined in a project's pom.xml. The latest version of the wagon can be found on the aws-maven page in Nexus.

<project>
  ...
  <build>
    ...
    <extensions>
      ...
      <extension>
        <groupId>com.vortexa</groupId>
        <artifactId>aws-maven</artifactId>
        <version>0.1.4</version>
      </extension>
      ...
    </extensions>
    ...
  </build>
  ...
</project>

Once the build extension is configured distribution management repositories can be defined in the pom.xml with an s3:// scheme.

<project>
  ...
  <distributionManagement>
    <repository>
      <id>aws-release</id>
      <name>AWS Release Repository</name>
      <url>s3://<BUCKET>/release</url>
    </repository>
    <snapshotRepository>
      <id>aws-snapshot</id>
      <name>AWS Snapshot Repository</name>
      <url>s3://<BUCKET>/snapshot</url>
    </snapshotRepository>
  </distributionManagement>
  ...
</project>

The code looks for the following three environment variables:

• AWS_ACCESS_KEY_ID
• AWS_SECRET_ACCESS_KEY
• AWS_SESSION_TOKEN

If all three are found, they are used for authentication. If not, settings.xml comes into play.

The ~/.m2/settings.xml must be updated to include access and secret keys for the account when not using environment-variable based session authentication.

The access key should be used to populate the username element, and the secret access key should be used to populate the password element.

<settings>
  ...
  <servers>
    ...
    <server>
      <id>aws-release</id>
      <username>0123456789ABCDEFGHIJ</username>
      <password>0123456789abcdefghijklmnopqrstuvwxyzABCD</password>
    </server>
    <server>
      <id>aws-snapshot</id>
      <username>0123456789ABCDEFGHIJ</username>
      <password>0123456789abcdefghijklmnopqrstuvwxyzABCD</password>
    </server>
    ...
  </servers>
  ...
</settings>

Alternatively, the access and secret keys for the account can be provided using

• AWS_ACCESS_KEY_ID (or AWS_ACCESS_KEY) and AWS_SECRET_KEY (or AWS_SECRET_ACCESS_KEY) environment variables
• aws.accessKeyId and aws.secretKey system properties
• The Amazon EC2 Instance Metadata Service

Making Artifacts Public

This wagon doesn't set an explict ACL for each artfact that is uploaded. Instead you should create an AWS Bucket Policy to set permissions on objects. A bucket policy can be set in the AWS Console and can be generated using the AWS Policy Generator.

In order to make the contents of a bucket public you need to add statements with the following details to your policy:

Effect	Principal	Action	Amazon Resource Name (ARN)
Allow	*	ListBucket	arn:aws:s3:::<BUCKET>
Allow	*	GetObject	arn:aws:s3:::<BUCKET>/*

If your policy is setup properly it should look something like:

{
  "Id": "Policy1397027253868",
  "Statement": [
    {
      "Sid": "Stmt1397027243665",
      "Action": [
        "s3:ListBucket"
      ],
      "Effect": "Allow",
      "Resource": "arn:aws:s3:::<BUCKET>",
      "Principal": {
        "AWS": [
          "*"
        ]
      }
    },
    {
      "Sid": "Stmt1397027177153",
      "Action": [
        "s3:GetObject"
      ],
      "Effect": "Allow",
      "Resource": "arn:aws:s3:::<BUCKET>/*",
      "Principal": {
        "AWS": [
          "*"
        ]
      }
    }
  ]
}

If you prefer to use the command line, you can use the following script to make the contents of a bucket public:

BUCKET=<BUCKET>
TIMESTAMP=$(date +%Y%m%d%H%M)
POLICY=$(cat<<EOF
{
  "Id": "public-read-policy-$TIMESTAMP",
  "Statement": [
    {
      "Sid": "list-bucket-$TIMESTAMP",
      "Action": [
        "s3:ListBucket"
      ],
      "Effect": "Allow",
      "Resource": "arn:aws:s3:::$BUCKET",
      "Principal": {
        "AWS": [
          "*"
        ]
      }
    },
    {
      "Sid": "get-object-$TIMESTAMP",
      "Action": [
        "s3:GetObject"
      ],
      "Effect": "Allow",
      "Resource": "arn:aws:s3:::$BUCKET/*",
      "Principal": {
        "AWS": [
          "*"
        ]
      }
    }
  ]
}
EOF
)

aws s3api put-bucket-policy --bucket $BUCKET --policy "$POLICY"