gadgethiServerUtils 0.0.38

Gadgethi server maintenance package

gadgethiServerUtils

This is the utility helper functions that can support the gadgethi server development.

Initial setup

Need to setup config_location parameter

config_location = "/opt/doday/doday-config/server-config.yaml"

and call generate_db_header

public pub pem key should be in /opt/doday/cert/* folder

Database Operations

This is the documentation for db_operations.py file.

Abstract Level

db_operations is the utility function used for performing low-level operations on database

A python PostgreSQL operation may consists of two parts:

1. String query

   sql = """SELECT * FROM order_table WHERE username = %s"""
   

2. Execute entries

   result = execute(sql,('Andrew))
   

3. Result would be optional, since some operations are POST actions that do not require fetching data.

Database Connection

PostgreSQL requires explicit functions to connect to database

Connection Psycopg2 connect_to_database

This function connects to the POSTGRESQL database.

By passing in test argument = True, the server connects to Test database.

Generate Query

There are four main query examples. We may find it painful if we have to type them all everytime.

Select = '''SELECT * FROM queue_table WHERE order_id = %s ORDER BY priority,time;'''

Update = '''UPDATE queue_table SET base = %s, soup = %s, main = %s, food1 = %s, food2 = %s, food3 = %s, special = %s, price = %s, discounted_price = %s ,promotion = %s, promotion_key = %s, priority = %s, status = %s WHERE order_id = %s;'''

Delete = '''DELETE FROM queue_table WHERE order_id = %s ;'''

Insert = '''INSERT into queue_table (order_id, order_no, base, soup, main, food1, food2, food3, special, price, discounted_price, promotion, promotion_key, priority, status, time) VALUES (%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s);'''

So Andrew wrote the generate_query series functions

Gerate Query Function generate_query

This function generalizes the query statements.

generate_query(table, action, target_column_list, conditional_column_list = 'None', order_by_list = 'None', limit_number = 'None'):

* required:
	- table: table to execute on (ex. 'order')
	- action: A valid psycopg2 command (ex. 'SELECT')
	- target_column_list: list of the column names after the ACTION statements (ex.['base','soup','food1']), SELECT * from order_tables means to select everything from order_table. In this case the target column list if the all_order_columns

* optionals:
	- conditional_column_list: list of the column names after the WHERE statement (ex. [username, store_id]), WHERE username = %s, store_id = %s. In this case we want to find the arguments that match.
	- order_by_list: Order by what ascending/descending order (ex.[priority DESC, time ASC, _id ASC]) Which means ORDER BY priority DESC, time ASC, _id ASC. 
	- limit_number: the number of fetched data you want (ex.1) limit 1.

* Returns:
	- table_action_query: the query you want.

Execute SQL

executeSql Function executeSql

def executeSql(db_path, sql, entries, mode, debug_print=False, header=False):

* required:
	- db_path: database path (ex.getDb('order))
	- sql: string generated from the previous generate_query function
	- entries: arguments matching the sql = %s parts, in tuple form
	- mode:
		mode = 0 -> normal execute
		mode = 1 -> execute with arguments
		mode = 2 -> with return values but without arguments
		mode = 3 -> with return values and with arguments	
* optionals:
	- debug_print: True if development mode. Default False
	- header: description for the command generated. Default False

* Returns:
	- ret: Response of the execute command.

Versioning

Gados-redbean-devel-v1.2.2

Authors

• Andrew Wong

License

This project is licensed under the MIT License - see the LICENSE.md file for details

Acknowledgments