quixoticmonk · February 11, 2021 18:08 · Jun 5, 2017
diff --git a/scan.py b/scan.py
@@ -0,0 +1,48 @@
+from __future__ import print_function # Python 2/3 compatibility
+import boto3
+import json
+import decimal
+from boto3.dynamodb.conditions import Key, Attr
+
+# Helper class to convert a DynamoDB item to JSON.
+class DecimalEncoder(json.JSONEncoder):
+    def default(self, o):
+        if isinstance(o, decimal.Decimal):
+            if o % 1 > 0:
+                return float(o)
+            else:
+                return int(o)
+        return super(DecimalEncoder, self).default(o)
+
+dynamodb = boto3.resource('dynamodb') # may require parameters if not using default AWS environment vars
+
+table = dynamodb.Table('Movies')
+
+fe = Key('year').between(1950, 1959);
+pe = "#yr, title, info.rating"
+# Expression Attribute Names for Projection Expression only.
+ean = { "#yr": "year", } # aliases for reserved keywords
+# http://docs.aws.amazon.com/amazondynamodb/latest/developerguide/ReservedWords.html
+esk = None
+
+response = table.scan(
+    FilterExpression=fe,
+    ProjectionExpression=pe,
+    ExpressionAttributeNames=ean
+    )
+
+for i in response['Items']:
+    print(json.dumps(i, cls=DecimalEncoder))
+    # or do something else, like items.append(i)
+
+while 'LastEvaluatedKey' in response:
+    response = table.scan(
+        ProjectionExpression=pe,
+        FilterExpression=fe,
+        ExpressionAttributeNames= ean,
+        ExclusiveStartKey=response['LastEvaluatedKey']
+        )
+
+    for i in response['Items']:
+        print(json.dumps(i, cls=DecimalEncoder))
+        # or do something else, like items.append(i)
No results found