System and custom metadata, System metadata available – HP StoreAll Storage User Manual

Page 161

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System and custom metadata

Two types of metadata are supported for queries, and both can be referenced in the same query:

System metadata applies to all files and directories. Each file and directory stored in StoreAll
includes a fixed set of attributes comprising its system metadata. System metadata attributes
are distinguished from custom metadata attributes by the system:: prefix. System metadata
attributes cannot be deleted by the user through the API.

Custom metadata applies only to files and directories where the user assigns them. Custom
metadata names are user-defined, with value strings also defined by the user. Custom metadata
is meaningful to the user, but it is not used by StoreAll. Custom metadata can be added,
replaced, or deleted by the user (see

“Custom metadata assignment” (page 152)

).

System metadata available

The following table describes the system metadata attributes available for query and updates using
the API.

For "date" types, see

“API date formats” (page 155)

.

With the exception of system::deleteTime, all of the system metadata attributes listed in this
table are valid for live (for example, not-yet-deleted) files and directories. For deleted files, only
the following attributes are valid: system::path, system::deleteTime,
system::lastActivityTime

and system::lastActivityReason.

Writable

Example

Description

Type

System attribute (key)

no

images/xray.jpg

The pathname of the
file or directory,

string

system::path

expressed as a path
relative to the mount
point of the StoreAll file
system.

This attribute is always
returned above the
JSON stanza of
requested attributes
within curly braces { },
not inside the stanza.

no

433

The StoreAll user ID
(UID) number of the

numeric

system::ownerUserId

owner of the file or
directory.

no

1025489

The file size. The
number of bytes stored

numeric

system::size

by StoreAll to hold the
file’s contents.

no

700

The StoreAll group ID
(GID) number of the

numeric

system::ownerGroupId

primary group to which
the owner of the file or
directory belongs.

Metadata queries

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