#!/bin/bash

##############################################################################
#
#    Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
#    SPDX-License-Identifier: Apache-2.0
#
###############################################################################

###############################################################################
#
#     Before running this AWS CLI example, set up your development environment, including your credentials.
#
#     For more information, see the following documentation topic:
#
#     https://docs.aws.amazon.com/cli/latest/userguide/getting-started-install.html
#
###############################################################################


source ./awsdocs_general.sh

# snippet-start:[aws-cli.bash-linux.dynamodb.CreateTable]
###############################################################################
# function dynamodb_create_table
#
# This function creates an Amazon DynamoDB table.
#
# Parameters:
#       -n table_name  -- The name of the table to create.
#       -a attribute_definitions -- JSON file path of a list of attributes and their types.
#       -k key_schema -- JSON file path of a list of attributes and their key types.
#       -p provisioned_throughput -- Provisioned throughput settings for the table.
#
#  Returns:
#       0 - If successful.
#       1 - If it fails.
###############################################################################
function dynamodb_create_table() {
  local table_name attribute_definitions key_schema provisioned_throughput response
  local option OPTARG # Required to use getopts command in a function.

  #######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_create_table"
    echo "Creates an Amazon DynamoDB table."
    echo " -n table_name  -- The name of the table to create."
    echo " -a attribute_definitions -- JSON file path of a list of attributes and their types."
    echo " -k key_schema -- JSON file path of a list of attributes and their key types."
    echo " -p provisioned_throughput -- Provisioned throughput settings for the table."
    echo ""
  }

  # Retrieve the calling parameters.
  while getopts "n:a:k:p:h" option; do
    case "${option}" in
      n) table_name="${OPTARG}" ;;
      a) attribute_definitions="${OPTARG}" ;;
      k) key_schema="${OPTARG}" ;;
      p) provisioned_throughput="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$table_name" ]]; then
    errecho "ERROR: You must provide a table name with the -n parameter."
    usage
    return 1
  fi

  if [[ -z "$attribute_definitions" ]]; then
    errecho "ERROR: You must provide an attribute definitions json file path the -a parameter."
    usage
    return 1
  fi

  if [[ -z "$key_schema" ]]; then
    errecho "ERROR: You must provide a key schema json file path the -k parameter."
    usage
    return 1
  fi

  if [[ -z "$provisioned_throughput" ]]; then
    errecho "ERROR: You must provide a provisioned throughput json file path the -p parameter."
    usage
    return 1
  fi

  iecho "Parameters:\n"
  iecho "    table_name:   $table_name"
  iecho "    attribute_definitions:   $attribute_definitions"
  iecho "    key_schema:   $key_schema"
  iecho "    provisioned_throughput:   $provisioned_throughput"
  iecho ""

  response=$(aws dynamodb create-table \
    --table-name "$table_name" \
    --attribute-definitions file://"$attribute_definitions" \
    --key-schema file://"$key_schema" \
    --provisioned-throughput "$provisioned_throughput")

  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports create-table operation failed.$response"
    return 1
  fi

  return 0
}
# snippet-end:[aws-cli.bash-linux.dynamodb.CreateTable]

###############################################################################
# function dynamodb_wait_table_active
#
# This function waits for a DynamoDB table to become active.
#
# Parameters:
#       -n table_name  -- The name of the table.
#
#  Returns:
#       0 - Table is active.
#       1 - If it fails.
###############################################################################
function dynamodb_wait_table_active() {
  local table_name
  local option OPTARG # Required to use getopts command in a function.

  #######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_wait_table_active"
    echo "Waits for a DynamoDB table to become active."
    echo "  -n table_name  -- The name of the table."
    echo ""
  }

  # Retrieve the calling parameters.
  while getopts "n:h" option; do
    case "${option}" in
      n) table_name="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$table_name" ]]; then
    errecho "ERROR: You must provide a table name with the -n parameter."
    usage
    return 1
  fi


  aws dynamodb wait table-exists \
    --table-name "$table_name"

   local error_code=${?}

    if [[ $error_code -ne 0 ]]; then
      aws_cli_error_log "$error_code"
      errecho "ERROR: AWS reports wait table-exists operation failed."
      return 1
    fi

  return 0
}

# snippet-start:[aws-cli.bash-linux.dynamodb.DescribeTable]
###############################################################################
# function dynamodb_describe_table
#
# This function returns the status of a DynamoDB table.
#
# Parameters:
#       -n table_name  -- The name of the table.
#
#  Response:
#       - TableStatus:
#     And:
#       0 - Table is active.
#       1 - If it fails.
###############################################################################
function dynamodb_describe_table {
  local table_name
  local option OPTARG # Required to use getopts command in a function.

  #######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_describe_table"
    echo "Describe the status of a DynamoDB table."
    echo "  -n table_name  -- The name of the table."
    echo ""
  }

  # Retrieve the calling parameters.
  while getopts "n:h" option; do
    case "${option}" in
      n) table_name="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$table_name" ]]; then
    errecho "ERROR: You must provide a table name with the -n parameter."
    usage
    return 1
  fi

  local table_status
    table_status=$(
      aws dynamodb describe-table \
        --table-name "$table_name" \
        --output text \
        --query 'Table.TableStatus'
    )

   local error_code=${?}

    if [[ $error_code -ne 0 ]]; then
      aws_cli_error_log "$error_code"
      errecho "ERROR: AWS reports describe-table operation failed.$table_status"
      return 1
    fi

  echo "$table_status"

  return 0
}
# snippet-end:[aws-cli.bash-linux.dynamodb.DescribeTable]

# snippet-start:[aws-cli.bash-linux.dynamodb.PutItem]
##############################################################################
# function dynamodb_put_item
#
# This function puts an item into a DynamoDB table.
#
# Parameters:
#       -n table_name  -- The name of the table.
#       -i item  -- Path to json file containing the item values.
#
#  Returns:
#       0 - If successful.
#       1 - If it fails.
##############################################################################
function dynamodb_put_item() {
  local table_name item response
  local option OPTARG # Required to use getopts command in a function.

  #######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_put_item"
    echo "Put an item into a DynamoDB table."
    echo " -n table_name  -- The name of the table."
    echo " -i item  -- Path to json file containing the item values."
    echo ""
  }

  while getopts "n:i:h" option; do
    case "${option}" in
      n) table_name="${OPTARG}" ;;
      i) item="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$table_name" ]]; then
    errecho "ERROR: You must provide a table name with the -n parameter."
    usage
    return 1
  fi

  if [[ -z "$item" ]]; then
    errecho "ERROR: You must provide an item with the -i parameter."
    usage
    return 1
  fi

  iecho "Parameters:\n"
  iecho "    table_name:   $table_name"
  iecho "    item:   $item"
  iecho ""
  iecho ""

  response=$(aws dynamodb put-item \
    --table-name "$table_name" \
    --item file://"$item")

  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports put-item operation failed.$response"
    return 1
  fi

  return 0

}
# snippet-end:[aws-cli.bash-linux.dynamodb.PutItem]

# snippet-start:[aws-cli.bash-linux.dynamodb.UpdateItem]
##############################################################################
# function dynamodb_update_item
#
# This function updates an item in a DynamoDB table.
#
#
# Parameters:
#       -n table_name  -- The name of the table.
#       -k keys  -- Path to json file containing the keys that identify the item to update.
#       -e update expression  -- An expression that defines one or more attributes to be updated.
#       -v values  -- Path to json file containing the update values.
#
#  Returns:
#       0 - If successful.
#       1 - If it fails.
#############################################################################
function dynamodb_update_item() {
  local table_name keys update_expression values response
  local option OPTARG # Required to use getopts command in a function.

  #######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_update_item"
    echo "Update an item in a DynamoDB table."
    echo " -n table_name  -- The name of the table."
    echo " -k keys  -- Path to json file containing the keys that identify the item to update."
    echo " -e update expression  -- An expression that defines one or more attributes to be updated."
    echo " -v values  -- Path to json file containing the update values."
    echo ""
  }

  while getopts "n:k:e:v:h" option; do
    case "${option}" in
      n) table_name="${OPTARG}" ;;
      k) keys="${OPTARG}" ;;
      e) update_expression="${OPTARG}" ;;
      v) values="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$table_name" ]]; then
    errecho "ERROR: You must provide a table name with the -n parameter."
    usage
    return 1
  fi

  if [[ -z "$keys" ]]; then
    errecho "ERROR: You must provide a keys json file path the -k parameter."
    usage
    return 1
  fi
  if [[ -z "$update_expression" ]]; then
    errecho "ERROR: You must provide an update expression with the -e parameter."
    usage
    return 1
  fi

  if [[ -z "$values" ]]; then
    errecho "ERROR: You must provide a values json file path the -v parameter."
    usage
    return 1
  fi

  iecho "Parameters:\n"
  iecho "    table_name:   $table_name"
  iecho "    keys:   $keys"
  iecho "    update_expression:   $update_expression"
  iecho "    values:   $values"

  response=$(aws dynamodb update-item \
    --table-name "$table_name" \
    --key file://"$keys" \
    --update-expression "$update_expression" \
    --expression-attribute-values file://"$values")

  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports update-item operation failed.$response"
    return 1
  fi

  return 0

}
# snippet-end:[aws-cli.bash-linux.dynamodb.UpdateItem]

# snippet-start:[aws-cli.bash-linux.dynamodb.GetItem]
#############################################################################
# function dynamodb_get_item
#
# This function gets an item from a DynamoDB table.
#
# Parameters:
#       -n table_name  -- The name of the table.
#       -k keys  -- Path to json file containing the keys that identify the item to get.
#       [-q query]  -- Optional JMESPath query expression.
#
#  Returns:
#       The item as text output.
#  And:
#       0 - If successful.
#       1 - If it fails.
############################################################################
function dynamodb_get_item() {
  local table_name keys query response
  local option OPTARG # Required to use getopts command in a function.

  # ######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_get_item"
    echo "Get an item from a DynamoDB table."
    echo " -n table_name  -- The name of the table."
    echo " -k keys  -- Path to json file containing the keys that identify the item to get."
    echo " [-q query]  -- Optional JMESPath query expression."
    echo ""
  }
  query=""
  while getopts "n:k:q:h" option; do
    case "${option}" in
      n) table_name="${OPTARG}" ;;
      k) keys="${OPTARG}" ;;
      q) query="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$table_name" ]]; then
    errecho "ERROR: You must provide a table name with the -n parameter."
    usage
    return 1
  fi

  if [[ -z "$keys" ]]; then
    errecho "ERROR: You must provide a keys json file path the -k parameter."
    usage
    return 1
  fi

  if [[ -n "$query" ]]; then
    response=$(aws dynamodb get-item \
      --table-name "$table_name" \
      --key file://"$keys" \
      --output text \
      --query "$query")
  else
    response=$(
      aws dynamodb get-item \
        --table-name "$table_name" \
        --key file://"$keys" \
        --output text
    )
  fi

  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports get-item operation failed.$response"
    return 1
  fi

  if [[ -n "$query" ]]; then
    echo "$response" | sed "/^\t/s/\t//1" # Remove initial tab that the JMSEPath query inserts on some strings.
  else
    echo "$response"
  fi

  return 0
}
# snippet-end:[aws-cli.bash-linux.dynamodb.GetItem]

# snippet-start:[aws-cli.bash-linux.dynamodb.DeleteItem]
##############################################################################
# function dynamodb_delete_item
#
# This function deletes an item from a DynamoDB table.
#
# Parameters:
#       -n table_name  -- The name of the table.
#       -k keys  -- Path to json file containing the keys that identify the item to delete.
#
#  Returns:
#       0 - If successful.
#       1 - If it fails.
###########################################################################
function dynamodb_delete_item() {
  local table_name keys response
  local option OPTARG # Required to use getopts command in a function.

  # ######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_delete_item"
    echo "Delete an item from a DynamoDB table."
    echo " -n table_name  -- The name of the table."
    echo " -k keys  -- Path to json file containing the keys that identify the item to delete."
    echo ""
  }
  while getopts "n:k:h" option; do
    case "${option}" in
      n) table_name="${OPTARG}" ;;
      k) keys="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$table_name" ]]; then
    errecho "ERROR: You must provide a table name with the -n parameter."
    usage
    return 1
  fi

  if [[ -z "$keys" ]]; then
    errecho "ERROR: You must provide a keys json file path the -k parameter."
    usage
    return 1
  fi

  iecho "Parameters:\n"
  iecho "    table_name:   $table_name"
  iecho "    keys:   $keys"
  iecho ""

  response=$(aws dynamodb delete-item \
    --table-name "$table_name" \
    --key file://"$keys")

  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports delete-item operation failed.$response"
    return 1
  fi

  return 0

}
# snippet-end:[aws-cli.bash-linux.dynamodb.DeleteItem]

# snippet-start:[aws-cli.bash-linux.dynamodb.Query]
#############################################################################
# function dynamodb_query
#
# This function queries a DynamoDB table.
#
# Parameters:
#       -n table_name  -- The name of the table.
#       -k key_condition_expression -- The key condition expression.
#       -a attribute_names -- Path to JSON file containing the attribute names.
#       -v attribute_values -- Path to JSON file containing the attribute values.
#       [-p projection_expression]  -- Optional projection expression.
#
#  Returns:
#       The items as json output.
#  And:
#       0 - If successful.
#       1 - If it fails.
###########################################################################
function dynamodb_query() {
  local table_name key_condition_expression attribute_names attribute_values projection_expression response
  local option OPTARG # Required to use getopts command in a function.

  # ######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_query"
    echo "Query a DynamoDB table."
    echo " -n table_name  -- The name of the table."
    echo " -k key_condition_expression -- The key condition expression."
    echo " -a attribute_names -- Path to JSON file containing the attribute names."
    echo " -v attribute_values -- Path to JSON file containing the attribute values."
    echo " [-p projection_expression]  -- Optional projection expression."
    echo ""
  }

  while getopts "n:k:a:v:p:h" option; do
    case "${option}" in
      n) table_name="${OPTARG}" ;;
      k) key_condition_expression="${OPTARG}" ;;
      a) attribute_names="${OPTARG}" ;;
      v) attribute_values="${OPTARG}" ;;
      p) projection_expression="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$table_name" ]]; then
    errecho "ERROR: You must provide a table name with the -n parameter."
    usage
    return 1
  fi

  if [[ -z "$key_condition_expression" ]]; then
    errecho "ERROR: You must provide a key condition expression with the -k parameter."
    usage
    return 1
  fi

  if [[ -z "$attribute_names" ]]; then
    errecho "ERROR: You must provide a attribute names with the -a parameter."
    usage
    return 1
  fi

  if [[ -z "$attribute_values" ]]; then
    errecho "ERROR: You must provide a attribute values with the -v parameter."
    usage
    return 1
  fi

  if [[ -z "$projection_expression" ]]; then
    response=$(aws dynamodb query \
      --table-name "$table_name" \
      --key-condition-expression "$key_condition_expression" \
      --expression-attribute-names file://"$attribute_names" \
      --expression-attribute-values file://"$attribute_values")
  else
    response=$(aws dynamodb query \
      --table-name "$table_name" \
      --key-condition-expression "$key_condition_expression" \
      --expression-attribute-names file://"$attribute_names" \
      --expression-attribute-values file://"$attribute_values" \
      --projection-expression "$projection_expression")
  fi

  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports query operation failed.$response"
    return 1
  fi

  echo "$response"

  return 0
}
# snippet-end:[aws-cli.bash-linux.dynamodb.Query]

# snippet-start:[aws-cli.bash-linux.dynamodb.Scan]
#############################################################################
# function dynamodb_scan
#
# This function scans a DynamoDB table.
#
# Parameters:
#       -n table_name  -- The name of the table.
#       -f filter_expression  -- The filter expression.
#       -a expression_attribute_names -- Path to JSON file containing the expression attribute names.
#       -v expression_attribute_values -- Path to JSON file containing the expression attribute values.
#       [-p projection_expression]  -- Optional projection expression.
#
#  Returns:
#       The items as json output.
#  And:
#       0 - If successful.
#       1 - If it fails.
###########################################################################
function dynamodb_scan() {
  local table_name filter_expression expression_attribute_names expression_attribute_values projection_expression response
  local option OPTARG # Required to use getopts command in a function.

  # ######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_scan"
    echo "Scan a DynamoDB table."
    echo " -n table_name  -- The name of the table."
    echo " -f filter_expression  -- The filter expression."
    echo " -a expression_attribute_names -- Path to JSON file containing the expression attribute names."
    echo " -v expression_attribute_values -- Path to JSON file containing the expression attribute values."
    echo " [-p projection_expression]  -- Optional projection expression."
    echo ""
  }

  while getopts "n:f:a:v:p:h" option; do
    case "${option}" in
      n) table_name="${OPTARG}" ;;
      f) filter_expression="${OPTARG}" ;;
      a) expression_attribute_names="${OPTARG}" ;;
      v) expression_attribute_values="${OPTARG}" ;;
      p) projection_expression="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$table_name" ]]; then
    errecho "ERROR: You must provide a table name with the -n parameter."
    usage
    return 1
  fi

  if [[ -z "$filter_expression" ]]; then
    errecho "ERROR: You must provide a filter expression with the -f parameter."
    usage
    return 1
  fi

  if [[ -z "$expression_attribute_names" ]]; then
    errecho "ERROR: You must provide expression attribute names with the -a parameter."
    usage
    return 1
  fi

  if [[ -z "$expression_attribute_values" ]]; then
    errecho "ERROR: You must provide expression attribute values with the -v parameter."
    usage
    return 1
  fi

  if [[ -z "$projection_expression" ]]; then
    response=$(aws dynamodb scan \
      --table-name "$table_name" \
      --filter-expression "$filter_expression" \
      --expression-attribute-names file://"$expression_attribute_names" \
      --expression-attribute-values file://"$expression_attribute_values")
  else
    response=$(aws dynamodb scan \
      --table-name "$table_name" \
      --filter-expression "$filter_expression" \
      --expression-attribute-names file://"$expression_attribute_names" \
      --expression-attribute-values file://"$expression_attribute_values" \
      --projection-expression "$projection_expression")
  fi

  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports scan operation failed.$response"
    return 1
  fi

  echo "$response"

  return 0
}
# snippet-end:[aws-cli.bash-linux.dynamodb.Scan]

# snippet-start:[aws-cli.bash-linux.dynamodb.BatchWriteItem]
##############################################################################
# function dynamodb_batch_write_item
#
# This function writes a batch of items into a DynamoDB table.
#
# Parameters:
#       -i item  -- Path to json file containing the items to write.
#
#  Returns:
#       0 - If successful.
#       1 - If it fails.
############################################################################
function dynamodb_batch_write_item() {
  local item response
  local option OPTARG # Required to use getopts command in a function.

  #######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_batch_write_item"
    echo "Write a batch of items into a DynamoDB table."
    echo " -i item  -- Path to json file containing the items to write."
    echo ""
  }
  while getopts "i:h" option; do
    case "${option}" in
      i) item="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$item" ]]; then
    errecho "ERROR: You must provide an item with the -i parameter."
    usage
    return 1
  fi

  iecho "Parameters:\n"
  iecho "    table_name:   $table_name"
  iecho "    item:   $item"
  iecho ""

  response=$(aws dynamodb batch-write-item \
    --request-items file://"$item")

  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports batch-write-item operation failed.$response"
    return 1
  fi

  return 0
}
# snippet-end:[aws-cli.bash-linux.dynamodb.BatchWriteItem]

# snippet-start:[aws-cli.bash-linux.dynamodb.BatchGetItem]
#############################################################################
# function dynamodb_batch_get_item
#
# This function gets a batch of items from a DynamoDB table.
#
# Parameters:
#       -i item  -- Path to json file containing the keys of the items to get.
#
#  Returns:
#       The items as json output.
#  And:
#       0 - If successful.
#       1 - If it fails.
##########################################################################
function dynamodb_batch_get_item() {
  local item response
  local option OPTARG # Required to use getopts command in a function.

  #######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_batch_get_item"
    echo "Get a batch of items from a DynamoDB table."
    echo " -i item  -- Path to json file containing the keys of the items to get."
    echo ""
  }

  while getopts "i:h" option; do
    case "${option}" in
      i) item="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$item" ]]; then
    errecho "ERROR: You must provide an item with the -i parameter."
    usage
    return 1
  fi

  response=$(aws dynamodb batch-get-item \
    --request-items file://"$item")
  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports batch-get-item operation failed.$response"
    return 1
  fi

  echo "$response"

  return 0
}
# snippet-end:[aws-cli.bash-linux.dynamodb.BatchGetItem]

# snippet-start:[aws-cli.bash-linux.dynamodb.ListTables]
##############################################################################
# function dynamodb_list_tables
#
# This function lists all the tables in a DynamoDB.
#
# Returns:
#       0 - If successful.
#       1 - If it fails.
###########################################################################
function dynamodb_list_tables() {
  response=$(aws dynamodb list-tables \
    --output text \
    --query "TableNames")

  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports batch-write-item operation failed.$response"
    return 1
  fi

  echo "$response" | tr -s "[:space:]" "\n"

  return 0
}
# snippet-end:[aws-cli.bash-linux.dynamodb.ListTables]

# snippet-start:[aws-cli.bash-linux.dynamodb.DeleteTable]
###############################################################################
# function dynamodb_delete_table
#
# This function deletes a DynamoDB table.
#
# Parameters:
#       -n table_name  -- The name of the table to delete.
#
#  Returns:
#       0 - If successful.
#       1 - If it fails.
###############################################################################
function dynamodb_delete_table() {
  local table_name response
  local option OPTARG # Required to use getopts command in a function.

  # bashsupport disable=BP5008
  function usage() {
    echo "function dynamodb_delete_table"
    echo "Deletes an Amazon DynamoDB table."
    echo " -n table_name  -- The name of the table to delete."
    echo ""
  }

  # Retrieve the calling parameters.
  while getopts "n:h" option; do
    case "${option}" in
      n) table_name="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$table_name" ]]; then
    errecho "ERROR: You must provide a table name with the -n parameter."
    usage
    return 1
  fi

  iecho "Parameters:\n"
  iecho "    table_name:   $table_name"
  iecho ""

  response=$(aws dynamodb delete-table \
    --table-name "$table_name")

  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports delete-table operation failed.$response"
    return 1
  fi

  return 0
}
# snippet-end:[aws-cli.bash-linux.dynamodb.DeleteTable]