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AWS Lex Plugin 1.3.0 Released

Amazon Web Services (AWS) Lex Speech Recognition Plugin 1.3.0 to the UniMRCP Server (UMS) has been released.

The plugin is based on the following components:

  • UniMRCP Server 1.6.0
  • AWS SDK 1.7.172

The binaries are currently available for the following Linux distributions:

  • Red Hat / CentOS 7 (unimrcp-lex-1.6.2-1.el7.x86_64.rpm)
  • Ubuntu 16.04 LTS(unimrcp-lex_1.6.2-xenial_amd64.deb)
  • Ubuntu 18.04 LTS(unimrcp-lex_1.6.2-bionic_amd64.deb)

This release is built against a newer version of AWS SDK.

With this release, the plugin can be configured to use the AWS default credentials provider chain, which in turn allows to derive an IAM role set on an instance UniMRCP server is running on. The behavior is controlled by a new configuration attribute 'credentials-provider', which is supposed to be set to 'default' to use the default credentials provider chain. Note, in such a case, the attribute 'credentials-file' is not observed.

The detailed list of changes introduced in this release follows.
New Features
  • Added support for an IAM role-based access to AWS services. See Sections 3.1 and 4.3 in the Usage Guide.
  • Added support for various new formats of 'instance' element in NLSML results. See Sections 3.3 and 5.3 in the Usage Guide.
Fixed Problems
  • Strip off double quotes from the values of vendor-specific parameters passed from GVP.
  • Fixed processing of data in SRGS XML item element spanning multiple lines.
  • Compose the header field Waveform-URI based on the protocol version. Before, the format defined in MRCPv2 was used unconditionally.
  • Fixed output format of RDRs to strictly conform to JSON.
Configuration Parameters
  • Added a new attribute 'credentials-provider', which can be set to either 'default' or 'custom'. The latter is used by default.
  • Added a new attribute 'tag-format' to the element 'results', which defaults to 'semantics/xml' and can also be set to 'semantics/json', 'swi-semantics/xml' and 'swi-semantics/json'.
  • Upgraded the AWS SDK from 1.5.16 to 1.7.172 version.
  • Output the AWS SDK version string in the logs.
  • 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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