View Source ExEtlFramework.Validator (ex_etl_framework v0.2.0)

Provides functions for validating data structures.

This module offers a flexible way to define validation rules and apply them to your data. It's particularly useful for ensuring data integrity at various stages of your ETL pipeline.

Example

schema = %{
  name: [&Validator.required/1, &Validator.type(String)],
  age: [&Validator.type(Integer)]
}
Validator.validate(%{name: "John", age: 30}, schema)

Summary

Functions

required(value)

Validates that a value is not nil.

type(expected_type)

Creates a validator function that checks if a value is of a specific type.

validate(data, schema)

Validates data against a given schema.

Functions

required(value)

Validates that a value is not nil.

Parameters

value: The value to check.

Returns

Returns either:

:ok if the value is not nil.
{:error, "Field is required"} if the value is nil.

Example

Validator.required("Some value")  # Returns :ok
Validator.required(nil)           # Returns {:error, "Field is required"}

type(expected_type)

Creates a validator function that checks if a value is of a specific type.

Parameters

expected_type: The type to check against (e.g., String, Integer).

Returns

Returns a function that takes a value and returns:

:ok if the value is of the expected type or nil.
{:error, reason} if the value is not of the expected type.

Example

string_validator = Validator.type(String)
string_validator.("Hello")  # Returns :ok
string_validator.(123)      # Returns {:error, "Expected type String, got 123"}

validate(data, schema)

Validates data against a given schema.

Parameters

data: The data structure to validate.
schema: A map where keys are field names and values are lists of validator functions.

Returns

Returns either:

{:ok, data} if all validations pass.
{:error, field, reason} if any validation fails.

Example

schema = %{name: [&Validator.required/1, &Validator.type(String)]}
Validator.validate(%{name: "John"}, schema)