POIS Reference Server

Release Notes

Date	Version	Update Notes
2022-09-30	1.0.27	Initial release containing support for ad rules only. API configuration only - See API section for details
2023-03-17	1.1.0	* Added support for time signal outputs * Added support for segmentation descriptor prioritization * Added logic for state lock

Overview

This is a POIS reference server capable of interacting with a transcoder using ESAM protocol.

It is intended to be used for testing purposes only.

Functionality

The functionality includes:

• SCTE35 filtering (deleting unwanted, passing through noop):

  • UPID value
  • segmentation type id (program,network, provider advertisement id,chapter start/stop)
  • splice command type (5,6)
  • UPID type

• Modify / Replace (free text entry with parameter validation)

  • splice command type 5 → 6 Will be supported at a later date
  • modify certain characteristics:
    • example: web_delivery_not_allowed
      • be aware that this may add more metadata to payload that needs to be taken into consideration
    • Adding/modifying segmentation_upid value

• SCTE35 driven archives Will be supported at a later date, integrating with AWS Elemental Live

  • Utilizing the Elemental Live API (requires public facing Elemental Live IP or NAT proxy)

• SCTE35 input switching Will be supported at a later date, integrating with AWS Elemental Live

  • Synchronous using inbound SCTE35 messages (Source switch logged in schedule stored in database)

Architecture

The architecture consists of several AWS services and is deployed using a CloudFormation template.

For OTT workflows, AWS Elemental Live needs to contribute the ESAM conditioned stream to AWS. Then through MediaConnect, MediaLive and MediaPackage/MediaStore can the OTT package be generated.

How to deploy

Use this CloudFormation template to deploy the solution.. Please note, the only resources deployed in this solution pertain to the POIS. Deployed Resources include:

• AWS Lambda Functions x 2
• AWS Lambda Layers * 2
• Amazon API Gateway REST API
• DynamoDB Channels Database
• DynamoDB Schedule Database
• DynamoDB State Database
• Amazon S3 ***bucket deployed to host UI ... later phase
• AWS IAM Role & Policy creation for Lambda Functions

API Control

At initial release, the only option to configure the POIS is via API. Once you've deployed the CloudFormation stack, check the Outputs tab. This will contain your API Endpoints.

The two most important output values are the ESAMEndpoint which you will configure in your encoder, and the ChannelConfigurationAPI value. This is the API endpoint you need to use to start setting up the POIS.

Method	Path	Description
GET	/pois/channels	Returns configuration of all channels in the POIS
GET	/pois/channels/{channel-name}	Where {channel-name} is the name of your channel, this will return the configuration of the channel
PUT	/pois/channels/{channel-name}	Where {channel-name} is the name of your channel, this will create/update the channel configuration in the POIS
DELETE	/pois/channels/{channel-name}	Where {channel-name} is the name of your channel, this will delete the channel from the POIS database

You can download the POSTman collection for this API set here: https://www.getpostman.com/collections/f91925ceece614b8486e

• When creating a channel in the API, only 2 properties are required:
  • default_behavior = this can either be noop or delete
  • esam_version = currently this value has to be 2013

Creating SCTE35 Rules

The POIS offers some rudimentary capabilities for SCTE35 signal conditioning and deleting. Here are some tips when configuring your rules:

• The rules are processed in order, starting with the first rule in the list submitted via the API
• The rule format is as follows:
  • You first specify an action type. What do you want to happen if the rule evaluates to TRUE (supported actions: replace, delete)
  • Then comes the condition; what do you want to evaluate. Currently, the application supports simple checks, ie. splice_command_type = 5 (splice_command_type is the property, 5 is the value, and the operator is =)
    • It is possibly to use multiple comma separated values that will be evaluated in order. ie. "value":"32,48,52"
  • For replace actions, you also need to submit with the json a replace_params list. If the evaluation of the rule is True, then the SCTE properties listed in the replace_params list will all be used to modify the SCTE35 binary
• You can mix and match action types in your rules. IE. you can have a DELETE rule to delete all splice_command_type 5 signals, then have a subsequent rule to modify duration
• It's recommended that any DELETE rules should be at earlier indexes in list than REPLACE rules
• There is currently no checking to see if rules you submit contradict each other, so please validate this before you configure the channel or you may not get the desired results
• For major replace actions, ie. if splice_command_type = 5, modify to splice_command_type = 6, the code does not fill in any blanks, so make sure your replace_params list contains all the new properties you want included in the new SCTE35 binary
• The code supports multiple operators:
  • '=' equal to
  • '>' greater than
  • '<' less than
  • '-' range (ie. if duration is between 15-30). When the operator is range, the value MUST have a min integer value, and a max integer value, separated by a hyphen '-'. For example value="2-4"
  • '!=' not equal to (this is useful for filtering/deleting anything that isn't a specific SCTE35 type. ie. if segmentation_upid_type != "9")
• Mode, this is optional and accepts values: "stateful" or "stateless"
  • stateful. The POIS will write to a DB for a rule it has matched with a replace action. Any subsequent SCTE signal received in the active window of the 'replaced' SCTE signal will be deleted
  • stateless. Each ESAM decision will be made independently
• Descriptor Priority, this is in the case of receiving a SCTE35 with multiple segmentation descriptors. Setting a comma delimited priority for which descriptor settings to preserve. ie. "32,34,48"

Note: If all the rules evaluate to FALSE, the configured default_behavior action will apply to the ESAM response

Here's a sample channel configuration:

{
  "default_behavior": "noop",
  "esam_version": "2013",
  "descriptor_priority":"",
  "mode":"stateless",
  "rules": [
    {
      "type": "delete",
      "condition":{
      "property": "splice_command_type",
      "value": "5",
      "operator": "="
      }
    },
    {
      "type": "replace",
      "condition":{
      "property": "duration",
      "value": "30",
      "operator": "<"
      },
      "replace_params":[
      {"duration":"60"},
      {"avail_expected":"2"}
      ]
    }
  ]
}

The channel has 2 rules; rule 1 is a delete rule that will evaluate to true if the incoming SCTE35 is a splice insert (splice_command_type=5). Rule 2 is evaluating the value of the break_duration property in the incoming SCTE35, and if the condition evaluates to true there are 2 replace_param properties that will override the corresponding properties of the incoming SCTE35 values