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AWS Lex Plugin 2.4.0 Released

Amazon Web Services (AWS) Lex Plugin 2.4.0 to the UniMRCP Server (UMS) has been released.

The plugin is based on the following components:

  • UniMRCP Server 1.7.0
  • AWS SDK 1.8.129
  • AWS Lex V2
  • Libevent 2.1.9
  • Libnghttp2 1.42.0

The binaries are currently available for the following Linux distributions:

  • Red Hat / CentOS 7 (unimrcp-lex-1.7.6-1.el7.x86_64.rpm)
  • Red Hat / CentOS 8 (unimrcp-lex-1.7.6-1.el8.x86_64.rpm)
  • Ubuntu 18.04 LTS (unimrcp-lex_1.7.6-bionic_amd64.deb)
  • Ubuntu 20.04 LTS (unimrcp-lex_1.7.6-focal_amd64.deb)

This release adds support for transparent session attributes of the Lex V2 API. The release also provides a few fixes and improvements in the existing functionality.

The detailed list of changes introduced in this release follows.
New Features
  • Allow session attributes of the Lex V2 API to be transparently specified either globally in the configuration file or per MRCP request via vendor-specific parameters.
  • Allow the session id of the Lex V2 API to be explicitly specified by the client by means of a vendor-specific parameter 'session-id'.
Fixed Problems
  • Fixed a possible segfault on processing the header field Logging-Tag having an empty [no] value.
  • Fixed processing of AWS profile parameters, including 'aws-arn-role', passed per MRCP request by the client.
  • Skip a fallback intent having the dialog action set to 'close' with no transcription, if the attribute 'skip-empty-results' is set to 'true', which is the default behavior.
Configuration Parameters
  • Added new attributes in the format of 'x-amz-lex.*' to the element 'streaming-recognition'. The name of the attribute must start with a prefix 'x-amz-lex' and a separator '.' must be used in the path. For example: x-amz-lex.audio.start-timeout-ms.
  • Updated the Usage Guide to reflect the changes introduced in this release.

Visit the Lex plugin page for more information.


Thank you for using UniMRCP.

Arsen Chaloyan
Author of UniMRCP

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