npitters / python-mapper-kata

A simple data translation kata to help exercise TDD skills

python-mapper-kata

The Scenario

Papillion Lavista High School (PLVHS) would like to upload statistics about their Track & Field ahtletes to the National Track & Field Database (NTFDB). The PLVHS event statistics are stored in json files, the data for each file needs to be translated to the format that the NTFDB requires.

Prerequisites

Poetry
Make

The Challenge

An application has been stubbed out in the app directory and tests in the tests directory. Using your TDD skills complete the transform function in the transformer.py module so that it can receive the PLVHS json data and transform it into json that the NTFDB expects. Examples of PLVHS input data can be found in the example_input directory. The mapping rules for the NTFDB data is defined in the mapping definition section below, all of these rules should be accounted for.

To run unit tests: make unit_tests
To execute the application: make run file=example_input/example_field.json (use any json file you want)

Mapping Definition

The following table defines all of the fields to be included in the NTFDB json data, the field that the data comes from in the PLVHS json data (if applicable) and any rules to apply to execute the mapping.

Note: Any required field that is either not included in the PLVHS data or is include but the value is null should result in an exception being raised.

Note: For any fields that require a translation, if a translation cannot be completed because the value is not included in the translation table then an execption should be raised.

NTFB Field (target)	Data Type	Required	PLVHS Field (source)	Rules
id	string	X	id
firstName	string		name	The name in the sourcde data is in the format first name + ' ' + last name. Map the first name part of of the source field. If for some reason the first name cannot be parsed out then leave it out of the target json.
lastName	string		name	The name in the source data is in the format first name + ' ' + last name. Map the last name part of of the source field. If for some reason the last name cannot be parsed out set this to the default value of "Unknown".
school	string	X		Always map hard coded value "Papillion Lavistia High School"
state	string	X		Always map hard coded value "NE"
grade	int	X	class	The grade should be mapped based on the Grade Mapping translation table.
classification	string	X	eventClassification	The classification should be mapped based on the Classification Mapping translation table.
eventName	string	X	eventId	The eventName should be mapped based on the Event Name Mapping translation table.
personalBest	string		times or marks	If the source eventTypeId == 1 (track) then this value is mapped from the times field. If eventTypeId == 2 (field) then this is mapped from the marks field. Each of these are pipe delimited values. If mapping from the times field then select the lowest time from the list. If mapping from the marks field then select the highest mark from the list. Additionaly, if mapping from the marks field the format of the values need to be translated. In the source data the format is xft yin, in the target data they need to be represted as x' y". If source value not present or is null then target value should be null
topThree	[string]	X	times or marks	If the source eventTypeId == 1 (track) then this value is mapped from the times field. If eventTypeId == 2 (field) then this is mapped from the marks field. Each of these are pipe delimited values. The target value is an array of 3 elements, and it always must be 3 elements. If mapping from times then it should be the 3 lowest times, if mapping from marks it should be the 3 highest marks. If 3 times or marks are not available then the array should be padded with null elements. The same rules for translating the format of marks applies.

Grade Mapping

Source Value	Target Value
Freshman	9
Sophomore	10
Junior	11
Senior	12

Classification Mapping

Source Value	Target Value
G	Girls
B	Boys

Event Name Mapping

Source Value	Target Value
1001	100m
1002	200m
1003	400m
1004	800m
1005	1600m
1006	3200m
2001	Long Jump
2002	Triple Jump
2003	Pole Vault
2004	High Jump
2005	Shot Put
2006	Discus