clear_cached_data

Clear all cached values for all records in a CachingTable

table_client.clear_cached_data()

Parameters

clear_cached_data has no parameters.

Availability

Table	Available
DynamoDBBasicTable	⬜
DynamoDBCachingTable	✅
ExternalDynamoDBApiBasicTable	⬜
ExternalDynamoDBApiCachingTable	✅

Example

Queried record

{

"userId": "x42",

"username": "Robinson"

}

Code

import json

from typing import Any, Optional

from StructNoSQL import TableDataModel, DynamoDBCachingTable, PrimaryIndex, BaseField

class UsersTableModel(TableDataModel):

userId = BaseField(field_type=str, required=True)

username = BaseField(field_type=str, required=False)

class UsersTable(DynamoDBCachingTable):

def __init__(self):

primary_index = PrimaryIndex(hash_key_name='userId', hash_key_variable_python_type=str)

super().__init__(

table_name='accounts-data', region_name='eu-west-2',

data_model=UsersTableModel, primary_index=primary_index,

auto_create_table=True

)

table_client = UsersTable()

table_client.debug = True

# Set debug to True to retrieve each value

# with its metadata (ie, the 'fromCache' attribute)

with open("record.json", 'r') as file:

source_record_data: dict = json.load(fp=file)

put_record_success: bool = table_client.put_record(record_dict_data=source_record_data)

if put_record_success is not True:

print("Error with put_record")

table_client.commit_operations()

table_client.clear_cached_data()

# put_record will cache our data, so we need to call commit_operations to

# make sure the record is created, then clear our cached_data a first time.

first_time_retrieved_username: Optional[Any] = table_client.get_field(

key_value='x42', field_path='username'

)

print(f"First retrieval username value : {first_time_retrieved_username}")

second_time_retrieved_username: Optional[Any] = table_client.get_field(

key_value='x42', field_path='username'

)

print(f"Second retrieval username value : {second_time_retrieved_username}")

table_client.clear_cached_data() # <-- We clear the cache

third_time_retrieved_username: Optional[Any] = table_client.get_field(

key_value='x42', field_path='username'

)

print(f"Third retrieval username value : {third_time_retrieved_username}")

Output

First retrieval username value : {'value': 'Robinson', 'fromCache': False}

Second retrieval username value : {'value': 'Robinson', 'fromCache': True}

Third retrieval username value : {'value': 'Robinson', 'fromCache': False}