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Read metadata from HCP

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You can use the Read metadata from HCP step to identify and select an HCP object by its URL path and then select a specific target annotation name to read. The step returns the requested custom metadata from the annotation back to your PDI transformation for downstream processing. You can use the Write metadata to HCP step to further refine the metadata within the transformation and write it back to HCP.

Hitachi Content Platform (HCP) is an object-based storage repository designed for unstructured data. To add structure and control to the data, HCP creates metadata annotations that are associated with each object. An HCP object consists of a read-only file, a unique URL, system metadata properties, and custom metadata annotations. Each annotation for an HCP object has its own annotation name (for example: myannotation0515202).

General

Enter the following information for the step:

  • Step name: Specify the unique name of the transformation on the canvas. You can customize the name or leave it as the default.

Options

Screen capture of read metadata from HCP objects step

In the step window, specify the HCP object URL for the transformation to locate. You can also select the default annotation or a specific target annotation name to read, located at the specified object URL. There are two methods for designating an object URL and target annotation name to read. You can:

  • Define and populate text fields within the transformation that contain the object URL or target annotation name (recommended).
  • Manually enter an object URL and annotation name.

You can create and populate text fields two ways: either by using a transformation variable or by using values from a PDI step, such as Query HCP, Data Grid, or Get File Names.

The Read metadata from HCP step contains the following options.

OptionDescription
HCP VFS ConnectionFrom the drop-down list, select the VFS connection you created for this transformation to connect to your HCP repository.
Select incoming field for your Object URLFrom the drop-down list, select the name of a text field that contains the target HCP object URL. This text field is defined by a previous step in the transformation.

You can also enter the object URL directly into the field. For example: https://test.hcptest.pentaho.net/axis.gif

Annotation to read from

Select a target annotation name to read, using one of the following options:

  • Use default

    Reads the contents of the default annotation associated with the object URL, which is identified in the Select incoming field for your Object URL option.

    NoteThis annotation is named default in HCP.
  • Incoming field

    From the drop-down list, select the name of the text field that identifies a specific HCP annotation name. The annotation name in the field must be located at the object URL as entered in the Select incoming field for your Object URL option.

  • Manual

    Enter a specific HCP annotation name into the text box, for example myannotation0515202. The text string is limited to 32 characters.

    The target annotation must be located at the object URL as enterred in the Select incoming field for your Object URL option.

Outgoing fieldSpecify the name of the field downstream in the transformation that will contain the data read from the designated object URL and annotation name.