Custom Error Example

This example demonstrates how to create and use custom error messages with explicit validation. The code in examples/ExplictValidation/custom_error.c shows how to validate an array of objects and generate custom error messages if validation fails.

Code Explanation

#include "CHashManipulatorOne.c"

CHashNamespace hash;
CHashObjectModule obj;
CHashArrayModule array;
CHashValidatorModule validator;

CHash *create() {
    return newCHashArray(
        newCHashObject("name", hash.newString("aaaaaaaaaaaa"), "age", hash.newNumber(26), "height", hash.newNumber(1.69), "married", hash.newBool(true)),
        newCHashObject("name", hash.newString("second name"), "age", hash.newNumber(42), "height", hash.newNumber(2.5), "married", hash.newBool(true)),
        newCHashObject("name", hash.newString("third name"), "age", hash.newNumber(55), "height", hash.newNumber(2.4), "married", hash.newBool(false))
    );
}

void validate(CHash *all_persons) {
    validator.ensure_Array(all_persons);
    CHash_for_in(person, all_persons, {
        validator.ensure_only_keys_cleaning_args(person, newCHashStringArray("name", "age", "height", "married"));
        validator.ensure_String_by_key(person, "name");
        validator.ensure_min_size_by_key(person, "name", 2);
        validator.ensure_max_size_by_key(person, "name", 30);
        validator.ensure_min_value_by_key(person, "age", 0);
        validator.ensure_max_value_by_key(person, "age", 120);
        validator.ensure_min_value_by_key(person, "height", 0.5);
        validator.ensure_max_value_by_key(person, "height", 2.5);
        validator.ensure_Bool_by_key(person, "married");
    });
}

CHash *create_custom_errors() {
    return newCHashArray(
        newCHashObject(CHASH_CODE, newCHashNumber(CHASH_WRONG_TYPE), CHASH_MESSAGE, newCHashString("my custom type error at #path# with #type# and #expected_type#")),
        newCHashObject(CHASH_CODE, newCHashNumber(CHASH_INVALID_KEY), CHASH_MESSAGE, newCHashString("my custom type error at #path# with #key# and #expected_keys#"))
    );
}

int main() {
    hash = newCHashNamespace();
    obj = hash.object;
    array = hash.array;
    validator = hash.validator;

    CHashArray *all_persons = create();
    validate(all_persons);
    CHash_catch(all_persons) {
        validator.generate_custom_error_cleaning_args(all_persons, create_custom_errors());
        char *message = hash.get_error_message(all_persons);
        printf("%s\n", message);
    }
    CHash_protected(all_persons) {
        CHash_print(all_persons);
    }
    hash.free(all_persons);
}

Validation Steps

1. Ensure Array: The validator.ensure_Array function checks if the input is an array.
2. Ensure Only Keys: The validator.ensure_only_keys_cleaning_args function ensures that each object in the array contains only the specified keys.
3. String Validation: The validator.ensure_String_by_key function checks if the 'name' key is a string.
4. String Length Validation: The validator.ensure_min_size_by_key and validator.ensure_max_size_by_key functions ensure the 'name' string length is within the specified range.
5. Numeric Validation: The validator.ensure_min_value_by_key and validator.ensure_max_value_by_key functions check if the 'age' and 'height' values are within the specified ranges.
6. Boolean Validation: The validator.ensure_Bool_by_key function checks if the 'married' key is a boolean.

Custom Error Handling

If any validation fails, the validator.generate_custom_error_cleaning_args function is used to generate a custom error message based on the predefined error codes and messages in the create_custom_errors function. This allows for more specific and informative error reporting.