//tag::ref-doc[]
= Amazon S3 Source

This source app supports transfer of files using the Amazon S3 protocol.
Files are transferred from the `remote` directory (S3 bucket) to the `local` directory where the application is deployed.

Messages emitted by the source are provided as a byte array by default. However, this can be
customized using the `--mode` option:

- *ref* Provides a `java.io.File` reference
- *lines* Will split files line-by-line and emit a new message for each line
- *contents* The default. Provides the contents of a file as a byte array

When using `--mode=lines`, you can also provide the additional option `--withMarkers=true`.
If set to `true`, the underlying `FileSplitter` will emit additional _start-of-file_ and _end-of-file_ marker messages before and after the actual data.
The payload of these 2 additional marker messages is of type `FileSplitter.FileMarker`. The option `withMarkers` defaults to `false` if not explicitly set.

See also link:../../../functions/common/metadata-store-common/README.adoc[MetadataStore] options for possible shared persistent store configuration used to prevent duplicate messages on restart.


=== mode = lines

==== Headers:

* `Content-Type: text/plain`
* `file_orginalFile: <java.io.File>`
* `file_name: <file name>`
* `correlationId: <UUID>` (same for each line)
* `sequenceNumber: <n>`
* `sequenceSize: 0` (number of lines is not know until the file is read)

==== Payload:

A `String` for each line.

The first line is optionally preceded by a message with a `START` marker payload.
The last line is optionally followed by a message with an `END` marker payload.

Marker presence and format are determined by the `with-markers` and `markers-json` properties.

=== mode = ref

==== Headers:

None.

==== Payload:

A `java.io.File` object.

== Options

The **$$s3$$** $$source$$ has the following options:

//tag::configuration-properties[]
Properties grouped by prefix:


=== file.consumer

$$markers-json$$:: $$When 'fileMarkers == true', specify if they should be produced as FileSplitter.FileMarker objects or JSON.$$ *($$Boolean$$, default: `$$true$$`)*
$$mode$$:: $$The FileReadingMode to use for file reading sources. Values are 'ref' - The File object, 'lines' - a message per line, or 'contents' - the contents as bytes.$$ *($$FileReadingMode$$, default: `$$<none>$$`, possible values: `ref`,`lines`,`contents`)*
$$with-markers$$:: $$Set to true to emit start of file/end of file marker messages before/after the data. Only valid with FileReadingMode 'lines'.$$ *($$Boolean$$, default: `$$<none>$$`)*

=== metadata.store.dynamo-db

$$create-delay$$:: $$Delay between create table retries.$$ *($$Integer$$, default: `$$1$$`)*
$$create-retries$$:: $$Retry number for create table request.$$ *($$Integer$$, default: `$$25$$`)*
$$read-capacity$$:: $$Read capacity on the table.$$ *($$Long$$, default: `$$1$$`)*
$$table$$:: $$Table name for metadata.$$ *($$String$$, default: `$$<none>$$`)*
$$time-to-live$$:: $$TTL for table entries.$$ *($$Integer$$, default: `$$<none>$$`)*
$$write-capacity$$:: $$Write capacity on the table.$$ *($$Long$$, default: `$$1$$`)*

=== metadata.store.gemfire

$$region$$:: $$Gemfire region name for metadata.$$ *($$String$$, default: `$$<none>$$`)*

=== metadata.store.jdbc

$$region$$:: $$Unique grouping identifier for messages persisted with this store.$$ *($$String$$, default: `$$DEFAULT$$`)*
$$table-prefix$$:: $$Prefix for the custom table name.$$ *($$String$$, default: `$$<none>$$`)*

=== metadata.store.mongo-db

$$collection$$:: $$MongoDB collection name for metadata.$$ *($$String$$, default: `$$metadataStore$$`)*

=== metadata.store.redis

$$key$$:: $$Redis key for metadata.$$ *($$String$$, default: `$$<none>$$`)*

=== metadata.store

$$type$$:: $$Indicates the type of metadata store to configure (default is 'memory'). You must include the corresponding Spring Integration dependency to use a persistent store.$$ *($$StoreType$$, default: `$$<none>$$`, possible values: `mongodb`,`gemfire`,`redis`,`dynamodb`,`jdbc`,`zookeeper`,`hazelcast`,`memory`)*

=== metadata.store.zookeeper

$$connect-string$$:: $$Zookeeper connect string in form HOST:PORT.$$ *($$String$$, default: `$$127.0.0.1:2181$$`)*
$$encoding$$:: $$Encoding to use when storing data in Zookeeper.$$ *($$Charset$$, default: `$$UTF-8$$`)*
$$retry-interval$$:: $$Retry interval for Zookeeper operations in milliseconds.$$ *($$Integer$$, default: `$$1000$$`)*
$$root$$:: $$Root node - store entries are children of this node.$$ *($$String$$, default: `$$/SpringIntegration-MetadataStore$$`)*

=== s3.common

$$endpoint-url$$:: $$Optional endpoint url to connect to s3 compatible storage.$$ *($$String$$, default: `$$<none>$$`)*
$$path-style-access$$:: $$Use path style access.$$ *($$Boolean$$, default: `$$false$$`)*

=== s3.supplier

$$auto-create-local-dir$$:: $$Create or not the local directory.$$ *($$Boolean$$, default: `$$true$$`)*
$$delete-remote-files$$:: $$Delete or not remote files after processing.$$ *($$Boolean$$, default: `$$false$$`)*
$$filename-pattern$$:: $$The pattern to filter remote files.$$ *($$String$$, default: `$$<none>$$`)*
$$filename-regex$$:: $$The regexp to filter remote files.$$ *($$Pattern$$, default: `$$<none>$$`)*
$$list-only$$:: $$Set to true to return s3 object metadata without copying file to a local directory.$$ *($$Boolean$$, default: `$$false$$`)*
$$local-dir$$:: $$The local directory to store files.$$ *($$File$$, default: `$$<none>$$`)*
$$preserve-timestamp$$:: $$To transfer or not the timestamp of the remote file to the local one.$$ *($$Boolean$$, default: `$$true$$`)*
$$remote-dir$$:: $$AWS S3 bucket resource.$$ *($$String$$, default: `$$bucket$$`)*
$$remote-file-separator$$:: $$Remote File separator.$$ *($$String$$, default: `$$/$$`)*
$$tmp-file-suffix$$:: $$Temporary file suffix.$$ *($$String$$, default: `$$.tmp$$`)*
//end::configuration-properties[]

== Amazon AWS common options

The Amazon S3 Source (as all other Amazon AWS applications) is based on the
https://github.com/spring-cloud/spring-cloud-aws[Spring Cloud AWS] project as a foundation, and its auto-configuration
classes are used automatically by Spring Boot.
Consult their documentation regarding required and useful auto-configuration properties.

Some of them are about AWS credentials:

- cloud.aws.credentials.accessKey
- cloud.aws.credentials.secretKey
- cloud.aws.credentials.instanceProfile
- cloud.aws.credentials.profileName
- cloud.aws.credentials.profilePath

Other are for AWS `Region` definition:

- cloud.aws.region.auto
- cloud.aws.region.static

And for AWS `Stack`:

- cloud.aws.stack.auto
- cloud.aws.stack.name

== Examples

```
java -jar s3-source.jar --s3.remoteDir=/tmp/foo --file.consumer.mode=lines
```
//end::ref-doc[]
