tS3Output – Docs for ESB 5.x

Component family

MapReduce/Output

Function

The tS3Output component receives data processed by its
preceding component and writes the data into a given S3 filesystem.
By default, the format used to write the data is S3N (S3 Native
Filesystem).

This component, along with the MapReduce family it belongs to, appears only when you are
creating a Map/Reduce Job.

Purpose

tS3Output writes data into a
given S3 filesystem.

Basic settings

Property type

Either Built-in or Repository.

Built-in: No property data stored
centrally.

Repository: Select the Repository
file where Properties are stored. The following fields are
pre-filled in using fetched data.

Schema and Edit
Schema

A schema is a row description. It defines the number of fields to be processed and passed on
to the next component. The schema is either Built-In or
stored remotely in the Repository.

Click Edit schema to make changes to the schema. If the
current schema is of the Repository type, three options are
available:

Built-In: You create and store the schema locally for this
component only. Related topic: see Talend Studio
User Guide.

Repository: You have already created the schema and
stored it in the Repository. You can reuse it in various projects and Job designs. Related
topic: see Talend Studio User Guide.

Force S3 format instead of the recommended
S3N

Select this check box to use the S3 format to write the data.
Otherwise, the default S3N format is used.

Note that the S3N format allows you to write structured data while
in the S3 format the data is flat.

Bucket and Folder

Enter the bucket name and its folder in which you need to write data. You need to separate
the bucket name and the folder name using a slash (/).

Access key and Secret
key

Enter the authentication information required to connect to the Amazon S3 bucket to be
used.

To enter the password, click the […] button next to the
password field, and then in the pop-up dialog box enter the password between double quotes
and click OK to save the settings.

File type

Type

Select the type of the file to be processed. The type of the file may be:

Action

Select an operation for writing data:

Create: Creates a file and write
data in it.

Overwrite: Overwrites the file
existing in the directory specified in the Folder field.

Row separator

Enter the separator used to identify the end of a row.

Field separator

Enter character, string or regular expression to separate fields for the transferred
data.

Include Header

Select this check box to output the header of the data.

This option is not available for a Sequence file.

Custom encoding

You may encounter encoding issues when you process the stored data. In that situation, select
this check box to display the Encoding list.

Select the encoding from the list or select Custom and
define it manually. This field is compulsory for database data handling.

This option is not available for a Sequence file.

Compress the data

Select the Compress the data check box to compress the
output data.

Hadoop provides different compression formats that help reduce the space needed for
storing files and speed up data transfer. When reading a compressed file, the Studio needs
to uncompress it before being able to feed it to the input flow.

Merge result to single file

Select this check box to merge the final part files into a single file and put that file in a
specified directory.

Once selecting it, you need to enter the path to, or browse to the
folder you want to store the merged file in. This directory is
automatically created if it does not exist.

The following check boxes are used to manage the source and the target files:

This option is not available for a Sequence file.

Advanced settings

Advanced separator (for number)

Select this check box to change the separator used for numbers. By
default, the thousands separator is a coma (,) and the decimal separator is a period (.).

This option is not available for a Sequence file.

Global Variables

ERROR_MESSAGE: the error message generated by the
component when an error occurs. This is an After variable and it returns a string. This
variable functions only if the Die on error check box is
cleared, if the component has this check box.

A Flow variable functions during the execution of a component while an After variable
functions after the execution of the component.

To fill up a field or expression with a variable, press Ctrl +
Space to access the variable list and choose the variable to use from it.

For further information about variables, see Talend Studio
User Guide.

Usage

In a Talend Map/Reduce Job, it is used as a start component and requires
a transformation component as output link. The other components used along with it must be
Map/Reduce components, too. They generate native Map/Reduce code that can be executed
directly in Hadoop.

Once a Map/Reduce Job is opened in the workspace, tS3Output as well as the MapReduce family appears in the Palette of the Studio.

Note that in this documentation, unless otherwise explicitly stated, a scenario presents
only Standard Jobs, that is to say traditional Talend data
integration Jobs, and non Map/Reduce Jobs.

Hadoop Connection

You need to use the Hadoop Configuration tab in the
Run view to define the connection to a given Hadoop
distribution for the whole Job.

When you configure this connection for tS3Output, you need to select the Use Datanode hostname check box.

This connection is effective on a per-Job basis.