ASL definition for audio generation workflow

audio-workflow-asl-definition.json

{
    "Comment": "Generates and save audio files for a given list ID.",
    "StartAt": "Get word list",
    "States": {
      "Get word list": {
        "Type": "Task",
        "Resource": "arn:aws:states:::lambda:invoke",
        "OutputPath": "$.Payload",
        "Parameters": {
          "Payload": {
            "list_id.$": "$.list_id",
            "last_word_token.$": "$.last_word_token"
          },
          "FunctionName": "${GetWordsForListIdFunction}"
        },
        "Retry": [
          {
            "ErrorEquals": [
              "Lambda.ServiceException",
              "Lambda.AWSLambdaException",
              "Lambda.SdkClientException"
            ],
            "IntervalSeconds": 2,
            "MaxAttempts": 6,
            "BackoffRate": 2
          }
        ],
        "Next": "Iterate over word batch"
      },
      "Iterate over word batch": {
        "Type": "Map",
        "Iterator": {
          "StartAt": "Generate audio file",
          "States": {
            "Generate audio file": {
              "Type": "Task",
              "Parameters": {
                "OutputFormat": "mp3",
                "OutputS3BucketName": "${PronunciationAudioBucket}",
                "OutputS3KeyPrefix": "audio/",
                "Text.$": "$.text",
                "VoiceId": "Zhiyu"
              },
              "Resource": "arn:aws:states:::aws-sdk:polly:startSpeechSynthesisTask",
              "Next": "Update item with audio file key",
              "ResultPath": "$.pollyOutput"
            },
            "Update item with audio file key": {
              "Type": "Task",
              "Resource": "arn:aws:states:::dynamodb:updateItem",
              "Parameters": {
                "TableName": "${TableName}",
                "Key": {
                  "PK": {
                    "S.$": "$.list_id"
                  },
                  "SK": {
                    "S.$": "$.word_id"
                  }
                },
                "UpdateExpression": "set #w.#a = :audioFileKey",
                "ExpressionAttributeValues": {
                  ":audioFileKey": {
                    "S.$": "$.pollyOutput.SynthesisTask.OutputUri"
                  }
                },
                "ExpressionAttributeNames": {
                  "#w": "Word",
                  "#a": "Audio file key"
                }
              },
              "Next": "Wait"
            },
            "Wait": {
              "Type": "Wait",
              "Seconds": 1,
              "End": true
            }
          }
        },
        "MaxConcurrency": 10,
        "ItemsPath": "$.word_list",
        "Next": "Is last_word_token present?",
        "ResultPath": "$.mapStepResult"
      },
      "Is last_word_token present?": {
        "Type": "Choice",
        "Default": "Get word list",
        "Choices": [
          {
            "Variable": "$.last_word_token",
            "IsNull": true,
            "Next": "Go to end"
          }
        ]
      },
      "Go to end": {
        "Type": "Pass",
        "End": true
      }
    }
}