Pros of validator

• More comprehensive validation capabilities, including built-in validation rules
• Supports both struct and field-level validation
• Offers custom validation functions and error messages

Cons of validator

• Steeper learning curve due to more complex API
• May be overkill for simple struct-to-map conversions
• Requires additional tags for validation rules

Code Comparison

mapstructure:

type Person struct {
    Name string `mapstructure:"name"`
    Age  int    `mapstructure:"age"`
}

var m = map[string]interface{}{"name": "John", "age": 30}
var p Person
mapstructure.Decode(m, &p)

validator:

type Person struct {
    Name string `validate:"required,min=2,max=50"`
    Age  int    `validate:"required,gte=0,lte=120"`
}

validate := validator.New()
err := validate.Struct(person)

Summary

mapstructure focuses on decoding maps into structs, while validator provides extensive validation capabilities. mapstructure is simpler to use for basic conversions, but validator offers more robust data validation features. Choose mapstructure for straightforward struct population from maps, and validator when you need comprehensive input validation.

Pros of govalidator

• Focuses on data validation with a wide range of built-in validation functions
• Supports custom validation rules and error messages
• Provides utility functions for string manipulation and type checking

Cons of govalidator

• Limited to validation and doesn't offer advanced struct mapping capabilities
• May require more manual work for complex data transformations
• Less flexible for handling nested structures compared to mapstructure

Code Comparison

mapstructure:

type Person struct {
    Name string `mapstructure:"name"`
    Age  int    `mapstructure:"age"`
}

var m = map[string]interface{}{"name": "John", "age": 30}
var p Person
mapstructure.Decode(m, &p)

govalidator:

type User struct {
    Name  string `valid:"required"`
    Email string `valid:"email"`
}

u := User{Name: "John", Email: "john@example.com"}
result, err := govalidator.ValidateStruct(u)

mapstructure excels at mapping between different data structures, especially when dealing with complex nested structures or interfaces. It's particularly useful for decoding configuration files or API responses into Go structs.

govalidator, on the other hand, specializes in data validation. It offers a wide range of built-in validators and allows for custom validation rules. While it doesn't provide the same level of struct mapping capabilities as mapstructure, it's more focused on ensuring data integrity and correctness.

Choose mapstructure for flexible data mapping and transformation, and govalidator for robust data validation and sanitization tasks.

Pros of ozzo-validation

• More flexible validation rules with built-in and custom validators
• Supports validation of nested structures and slices
• Provides detailed error messages for failed validations

Cons of ozzo-validation

• Requires more setup and code for basic validations
• Learning curve for custom validation rules
• May be overkill for simple data binding scenarios

Code Comparison

mapstructure:

type Person struct {
    Name string `mapstructure:"name"`
    Age  int    `mapstructure:"age"`
}

var m = map[string]interface{}{"name": "John", "age": 30}
var p Person
mapstructure.Decode(m, &p)

ozzo-validation:

type Person struct {
    Name string
    Age  int
}

func (p Person) Validate() error {
    return validation.ValidateStruct(&p,
        validation.Field(&p.Name, validation.Required),
        validation.Field(&p.Age, validation.Required, validation.Min(0)),
    )
}

mapstructure focuses on decoding map data into structs, while ozzo-validation provides a more comprehensive validation framework. mapstructure is simpler to use for basic data binding, but ozzo-validation offers more control over validation rules and error reporting. Choose mapstructure for straightforward struct population, and ozzo-validation for complex validation scenarios with detailed error handling.

Pros of structs

• Simpler API for basic struct operations (e.g., converting to map, getting field names)
• Supports both struct tags and field names for flexible mapping
• Includes utility functions for working with struct fields (e.g., IsZero, HasZero)

Cons of structs

• Less powerful decoding capabilities compared to mapstructure
• Limited support for nested structs and complex data structures
• Fewer options for customizing the mapping process

Code Comparison

structs:

m := structs.Map(person)
names := structs.Names(person)

mapstructure:

var result Person
err := mapstructure.Decode(input, &result)

Key Differences

• structs focuses on struct-to-map conversions and field operations
• mapstructure specializes in decoding maps or JSON into structs
• structs has a more straightforward API for basic struct manipulations
• mapstructure offers more advanced decoding features and customization options

Use Cases

• Choose structs for simple struct-to-map conversions and basic field operations
• Opt for mapstructure when dealing with complex data structures or requiring advanced decoding capabilities

Pros of Cast

• Specialized in type conversion, offering a wide range of casting functions
• Simpler API for basic type conversions
• Includes additional utility functions like ToTimeE and ToDurationE

Cons of Cast

• Less flexible for complex struct mapping scenarios
• Doesn't support custom decoding logic for specific fields
• Limited options for handling nested structures

Code Comparison

Cast:

value := cast.ToString(123)
number := cast.ToInt([]byte("456"))

Mapstructure:

var result MyStruct
err := mapstructure.Decode(input, &result)

Key Differences

Mapstructure focuses on decoding map-like structures into Go structs, offering more advanced features for complex mapping scenarios. It provides greater flexibility in handling nested structures and custom decoding logic.

Cast, on the other hand, specializes in straightforward type conversions between various Go types. It offers a simpler API for basic casting operations but lacks the advanced struct mapping capabilities of Mapstructure.

Choose Cast for simple type conversions and basic casting needs. Opt for Mapstructure when dealing with complex struct mapping, nested structures, or when you need more control over the decoding process.