From 7fb6889e69d109c9deaafd96141a71f3ac47e35e Mon Sep 17 00:00:00 2001
From: Abdel Jaidi <jaidisido@gmail.com>
Date: Thu, 16 Jun 2022 15:24:38 +0100
Subject: [PATCH] (refactor): Refactor DynamoDB read_partiql method

---
 awswrangler/dynamodb/_read.py  | 37 +++++++++++++++++-----------------
 awswrangler/dynamodb/_utils.py | 17 ----------------
 2 files changed, 18 insertions(+), 36 deletions(-)

diff --git a/awswrangler/dynamodb/_read.py b/awswrangler/dynamodb/_read.py
index 0e1f28067..160401d58 100644
--- a/awswrangler/dynamodb/_read.py
+++ b/awswrangler/dynamodb/_read.py
@@ -8,10 +8,9 @@
 import pandas as pd
 from boto3.dynamodb.types import TypeDeserializer
 
+from awswrangler import _utils
 from awswrangler._config import apply_configs
 
-from ._utils import get_client
-
 _logger: logging.Logger = logging.getLogger(__name__)
 
 
@@ -42,22 +41,25 @@ def _get_terms_groups(terms: List[str]) -> Tuple[List[str], List[str], List[str]
     return select_terms, from_terms, where_terms
 
 
-def _get_scan_response(table_name: str, select_terms: List[str], client: boto3.resource) -> List[Dict[str, Any]]:
+def _get_scan_response(
+    table_name: str, select_terms: List[str], boto3_session: Optional[boto3.Session] = None
+) -> List[Dict[str, Any]]:
     """Perform a scan to the Dynamo DB table and returns the data fetched."""
+    client_dynamodb = _utils.client(service_name="dynamodb", session=boto3_session)
     scan_config: Dict[str, Any] = {"TableName": table_name}
     if len(select_terms) > 1 or select_terms[0] != "*":
         scan_config["AttributesToGet"] = select_terms
     # get all responses even if pagination is necessary
-    response = client.scan(**scan_config)
+    response = client_dynamodb.scan(**scan_config)
     data: List[Dict[str, Any]] = response["Items"]
     while "LastEvaluatedKey" in response:
         scan_config["ExclusiveStartKey"] = response["LastEvaluatedKey"]
-        response = client.scan(**scan_config)
+        response = client_dynamodb.scan(**scan_config)
         data.extend(response["Items"])
     return data
 
 
-def _get_items(client: boto3.resource, query: str) -> List[Dict[str, Any]]:
+def _get_items(query: str, boto3_session: Optional[boto3.Session] = None) -> List[Dict[str, Any]]:
     # clean input query from possible excessive whitespace
     query = re.sub(" +", " ", query).strip()
     # generate terms list from query
@@ -70,8 +72,7 @@ def _get_items(client: boto3.resource, query: str) -> List[Dict[str, Any]]:
     if len(from_terms) == 0:
         raise ValueError("The PartiQL query contains no tables.")
     table_name = from_terms[0]
-    data = _get_scan_response(table_name, select_terms, client)
-    return data
+    return _get_scan_response(table_name=table_name, select_terms=select_terms, boto3_session=boto3_session)
 
 
 def _deserialize_value(value: Any) -> Any:
@@ -87,11 +88,13 @@ def _deserialize_data(df: pd.DataFrame, columns: pd.Index) -> pd.DataFrame:
     return df
 
 
-def _parse_dynamodb_results(results: List[Dict[str, Any]]) -> pd.DataFrame:
-    df = pd.DataFrame(results)
-    columns = df.columns
-    df = _deserialize_data(df, columns)
-    return df
+def _parse_dynamodb_items(
+    items: List[Dict[str, Any]],
+    dtype: Optional[Dict[str, str]] = None,
+) -> pd.DataFrame:
+    df = pd.DataFrame(items)
+    df = _deserialize_data(df, df.columns)
+    return df.astype(dtype=dtype) if dtype else df
 
 
 @apply_configs
@@ -140,10 +143,6 @@ def read_partiql_query(
     ...     dtype={'key': int}
     ... )
     """
-    client = get_client(boto3_session)
     _logger.debug("Reading results for PartiQL query:  %s", query)
-    items = _get_items(client, query)
-    df = _parse_dynamodb_results(items)
-    if dtype:
-        df = df.astype(dtype=dtype)
-    return df
+    items = _get_items(query=query, boto3_session=boto3_session)
+    return _parse_dynamodb_items(items=items, dtype=dtype)
diff --git a/awswrangler/dynamodb/_utils.py b/awswrangler/dynamodb/_utils.py
index bb960a82e..0baecf726 100644
--- a/awswrangler/dynamodb/_utils.py
+++ b/awswrangler/dynamodb/_utils.py
@@ -34,23 +34,6 @@ def get_table(
     return dynamodb_table
 
 
-@apply_configs
-def get_client(boto3_session: Optional[boto3.Session] = None) -> boto3.client:
-    """Get DynamoDB client.
-
-    Parameters
-    ----------
-    boto3_session : Optional[boto3.Session()]
-        Boto3 Session. The default boto3 Session will be used if boto3_session receive None.
-
-    Returns
-    -------
-    client : boto3.Client
-        Boto3 DynamoDB client.
-    """
-    return _utils.client(service_name="dynamodb", session=boto3_session)
-
-
 def _validate_items(
     items: Union[List[Dict[str, Any]], List[Mapping[str, Any]]], dynamodb_table: boto3.resource
 ) -> None: