appsync-tools

##Provides helpful tools for parsing database responses and handling routes inside of Lambda for AWS Appsync.

DB response parsing

Aurora results are returned as a list of dictionaries with the column names being the key. Nulls (returned by Aurora as isNull) are returned as None types. Any value that can be parsed as json is cast from a string to a list/dictionary. Responses are returned formated as:

  [
    {"columnOneName": "value", "columnTwoName": "value"},
    {"columnOneName": "value", "columnTwoName": "value"}
  ]

Where each item in the top level array is a separate row.

Dynamodb results are returned as either a dictionary (for get_item operations) or a list of dictionaries (query).

Pretty parsing Aurora records

pretty_parse_aurora(records, type_attribute=None) -> list

Arguments:

• records -- The records from the API query (execute_statement()["records"])

Keyword Args:

• type_attribute -- If used will pass results to typify(results, type_attribute=type_attribute) before returning

  from appsync_tools import pretty_parse_aurora

  response = client.execute_statement(
      secretArn=environ["PG_SECRET"],
      database=environ["DB_NAME"],
      parameters=parameters,
      resourceArn=environ["DB_ARN"],
      includeResultMetadata=True,
      sql=sql
  )
  print(pretty_parse_aurora(response))

Parsing Dynamodb records

pretty_parse_dynamo(records, type_attribute=None) -> list | dict

Arguments:

• records -- The Item(s) from a call to query, get_item

Keyword Args:

• type_attribute -- If used will pass results to typify(results, type_attribute=type_attribute) before returning

  from appsync_tools import pretty_parse_dynamo

  response = client.get_item(
    Key={"pk": "foo", "sk": "bar"}
  )
  print(response.get("Item"))

Adding __typename to all records based on an attribute

typify(records, type_attribute="type") -> list | dict Arguments:

• records -- The Item(s) from a call to query, get_item

Keyword Args:

• type_attribute -- Attribute name that contains the __typename value

Example

  from appsync_tools import typify

  response = client.get_item(
    Key={"pk": "foo", "sk": "BarType"}
  )

  print(typify(response.get("Item"), type_attribute="sk"))