BasicSearchFilter

//DynamoDB table with Primary Key "id" and each item has attributes "title" and "author
//If you have an item in the table that only has one of these attributes, the search will fail
//Use the below GraphQL schema:

type Post {
	id: ID!
	title: String!
	author: String!
}

type Query {
	searchByCity(title: String!): [Post]
}

//Attach a resolver with the following filter on the request template to look for items that match your input value for title
{
    "version" : "2017-02-28",
    "operation" : "Scan",
    "filter" : {
        "expression" : "contains(#title, :title)",
        "expressionNames" : {
            "#title" : "title"
        },
        "expressionValues" : {
            ":title" : $util.dynamodb.toDynamoDBJson($ctx.args.title)
        }
    }
}

//The response template in the resolver will pass back the results that match:
$util.toJson($ctx.result.items)

//Now you can run a query and any items that have "Hello" in the title will be returned:
query {
  searchByCity(title:"Hello"){
    id
    title
    author
  }
}