PLEASE NOTE: This documentation applies to an earlier version. For the most recent documentation, visit the Pentaho Enterprise Edition documentation site.

Description

The JSON Input step extracts relevant portions out of JSON structures, files or incoming fields, and outputs rows.

Options

File Tab

The File tab is where you enter basic connection information for accessing a resource.

Option	Definition
Step name	Name of this step as it appears in the transformation workspace
Source is from a previous step	Retrieves the source from a previously defined field
Select field	The field name to use as a source from a previous step
Use field as file names	Indicates source is a filename
Read source as URL	Indicates a source should be accessed as a URL
Do not pass field downstream	The source field will be removed from the output stream. This improves performance and memory utilization with large JSON fields.
File or directory	Indicates the location of the source if the source is not defined in a field
Regular expression	All filenames that match this regular expression are selected if a directory is specified
Exclude regular expression	All filenames that match this regular expression are excluded if a directory is specified
Show filename	Displays the file names of the connected source

Content Tab

The Content tab enables you to configure which data to collect.

Option	Definition
Ignore empty file	When checked, indicates to skip empty files---when unchecked, instances of empty files causes the process fail and stop
Do not raise an error if no files	When unchecked, causes the transformation to fail when there is no file to process---then checked, avoids failure when there is no file to process
Ignore missing path	When unchecked, causes the transformation to fail when the JSON path is missing---then checked, avoids failure when there is no JSON path
Limit	Sets a limit on the number of records generated from the step when set greater than zero
Include filename in output	Adds a string field with the filename in the result
Rownum in output	Adds an integer field with the row number in the result
Add files to result filesname	If checked, adds processed files to the result file list

Fields Tab

The Fields tab displays field definitions to extract values from the JSON structure. This step uses JSONPath to extract fields from JSON structures.

Additional Output Fields Tab

The Additional output fields tab enables you to provide additional information about the file to process.

Examples

Pentaho Data Integration ships with sample transformations you can run to demonstrate step functionality. To open a sample transformation, from within the Spoon interface, go to the File menu and select Open. Browse to pentaho\design-tools\data-integration\samples\transformations, then select the sample transformation you want to run. Within this directory are several sample transformations to demonstrate the functionality of this step.

JsonInput - read a dynamic file.ktr
JsonInput - read a file.ktr
JsonInput - read incoming stream.ktr

Metadata Injection Support (7.x and later)

All fields of this step support metadata injection. You can use this step with ETL Metadata Injection to pass metadata to your transformation at runtime.