Insert Multiple records in dynamodb using api gateway

Question

How can I insert multiple rows in dynamodb using body mapping template of API gateway?

Input to my code is "xyz 1,abc 2" which has information about 2 rows to be inserted.

Only second record which is "abc 2" is getting stored, I want both records to be inserted in the table. Below is the code I have written

#set($rawAPIData = $input.path('$'))
#set ($bulk = $rawAPIData.split(","))
{
"TableName": "tablename",
#foreach( $records in $bulk)
#set ($s = $records.split(" "))
"Item": {
    "col1": {
            "S": "$s.get(0)"
    },
    "col2": {
            "S": "$s.get(1)"
    }

}
#if( $foreach.hasNext ), #end
#end
}

I'm new to this, suggestion would really help

Answer 1

This AWS guide shows how to use API Gateway as a proxy for DynamoDB. It's similar the approach you are trying to take. As a suggestion, it might be better have your api focus on a single row at a time, rather than splitting multiple inputs on ,. For example it would simplify your template somewhat to send requests similar to those found in the guide.

Example Request Body:

{ 
  "col1": "xyz",
  "col2": "1"
}

Template (derived from your template code):

{ 
    "TableName": "tablename",
    "Item": {
      "col1": {
          "S": "$input.path('$.col1')"
          },
      "col2": {
          "S": "$input.path('$.col2')"
         }
    }
}

However, if you want to stick to operating on multiple items, The BatchWriteItem documentation would be worth a read. Following the example, I think this should be your body template:

#set($rawAPIData = $input.path('$'))
#set ($bulk = $rawAPIData.split(","))
{
  "RequestItems": {
    "tablename": [
      #foreach($records in $bulk)
      #set ($s = $records.split(" "))
      {
        "PutRequest": {
          "Item": {
            "col1": {
               "S": "$s.get(0)"
            },
            "col2": {
              "S": "$s.get(1)"
            }
          }
        }
      }
     #if( $foreach.hasNext ), 
     #end
    ]
  }
#end
}