Metadata for record file management

You use metadata attributes to control how the trading engine handles the file records that are transported in messages.

You can set these attributes:

Local and virtual attributes

Metadata attributes for file records are classed as either local or virtual attributes:

  • Local attributes (for example, LocalFileRecordFormat) apply to document files stored on the Activator file system. Local attributes describe how file records are structured and in what character set the record is encoded. This enables the trading engine to process documents correctly.
  • Virtual attributes (for example, VirtualFileRecordFormat) are used by file-transfer protocols such as PeSIT, to describe the files being transferred. Virtual attributes are conveyed by a protocol during the exchange to the partner. This tells the partner what is being transferred and how to process the file once received.

Sent messages

For sending messages, file attributes are defined in a message attributes template or in the Message Handler:

  • If LocalFileRecordFormat is not given, OCTET_STREAM is assumed (the default value).
  • If LocalFileRecordFormat is FIXED_TEXT or FIXED_BINARY, LocalRecordLength is required.
  • If LocalFileRecordFormat is VARIABLE_TEXT or VARIABLE_BINARY, LocalRecordLength is optional.
  • If LocalFileCharSet is not given, ASCII is assumed.
  • LocalFilePaddingCode is required only in case of record transcoding.
  • Virtual file attributes are optional. If virtual file attributes are not given, the corresponding local file attributes are assumed.
  • If VirtualFileRecordFormat is different than LocalFileRecordFormat or the LocalFileChatSet is different than VirtualFileChatset, the file undergoes transcoding before being sent.

Consumed messages

For consumed messages, virtual file attributes are provided by the protocol elements (metadata), as conveyed during the protocol exchange. Local file attributes are assumed to be the same as virtual file attributes received. However, you can use the record transformation options of the Message Handler to override these attributes and set file transcoding as needed. Additionally, for PeSIT message consumption, virtual and local file attribute values can be overridden by applying a message attributes template on the PeSIT pickup.

Transcoding

Transcoding applies only to files that have a record structure and not to OCTET_STREAM (unstructured) files. Transcoding occurs when LocalFileRecordFormat is different from VirtualFileRecordFormat or LcoalFileCharSet is different from VirtualFileCharset. File records can be transformed from FIX_ to VARIABLE_ format or vice-versa.

For outbound messages, transformation takes local file attributes as source attributes and virtual file attributes as target attributes. For inbound message, it is the other way round.

When transformed from FIX_ to VARIABLE_, trailing padding characters (as defined in LocalFilePaddingChar or VirtualFilePaddingChar) are stripped off to make the record in variable format.

When transformed from VARIABLE_ to FIX_ , padding characters (as defined in LocalFilePaddingChar or VirtualFilePaddingChar) are added to make the record in fixed format. The process assumes fixed format record length is at least as long as the maximum variable format record.

Attributes

Attribute Value

Description

LocalFileCharSet
  • ASCII
  • EBCDIC
  • Free

Name of the character set used in the local file.

LocalFilePaddingChar
  • 0x00…0x7F

Padding character used in the local file.

LocalFileRecordFormat
  • FIXED_BINARY
  • VARIABLE_BINARY
  • FIXED_TEXT
  • VARIABLE_TEXT
  • OCTET_STREAM

Format of the local file record.

To turn off transcoding, set this value to OCTET_STREAM

LocalFileRecordLength
  • Length in bytes

Size (for fixed length) or maximum size (for variable length) of the file record.

VirtualFileCharSet
  • ASCII
  • EBCDIC
  • Free
Name of the character set for the file flowing over the network
VirtualFilePaddingChar
  • 0x00…0x7F
Padding character used in the file over the network
VirtualFileRecordFormat
  • FIXED_BINARY
  • VARIABLE_BINARY
  • FIXED_TEXT
  • VARIABLE_TEXT
  • OCTET_STREAM

Format of the virtual file record.

To turn off transcoding, set this value to OCTET_STREAM

VirtualFileRecordLength
  • Length in bytes
Size (for fixed length) or maximum size (for variable length) of the file record.
message.attributes.template .in/out
  • Message Attributes Template name
Indicates the Message Attribute Template applied on reception/ on sending

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