Struct UserId 

pub struct UserId(/* private fields */);

User identifier value object for type-safe authentication and authorization

This value object provides type-safe user authentication with authorization management, identity validation, and comprehensive security features. It implements Domain-Driven Design (DDD) value object patterns with multiple user ID format support.

Key Features

• Type Safety: Strongly-typed user identifiers that cannot be confused with other string types
• Authentication: Comprehensive user authentication with format validation
• Authorization: User-specific permission checking and access control
• Cross-Platform: Consistent representation across languages and storage systems
• Security Features: Audit trails, user classification, and domain management
• Serialization: Full serialization support for storage and API integration

Benefits Over Raw Strings

• Type Safety: UserId cannot be confused with other string types
• Domain Semantics: Clear intent in function signatures and authentication business logic
• User Validation: Comprehensive validation rules and format checking
• Future Evolution: Extensible for user-specific methods and security features

Security Benefits

• Type Safety: Cannot be confused with other string types in security contexts
• Validation: Format checking and constraint enforcement for reliable authentication
• Audit Trails: Clear user action tracking and accountability
• Authorization: User-specific permission checking and access control

User ID Formats

• Email: user@domain.com (most common, normalized to lowercase)
• Username: username123 (alphanumeric with underscores and hyphens)
• UUID: 550e8400-e29b-41d4-a716-446655440000 (standard UUID format)
• System: system-backup (automatically prefixed system accounts)
• API: api-webhook (automatically prefixed API accounts)

Use Cases

• User Authentication: Authenticate users with various ID formats
• Authorization Management: User-specific permission checking and access control
• Identity Validation: Comprehensive format validation and constraint enforcement
• Audit Trails: Track user actions with proper identification

Usage Examples

Cross-Language Mapping

• Rust: UserId newtype wrapper with full validation
• Go: UserID struct with equivalent interface
• JSON: String representation for API compatibility
• Database: TEXT column with validation constraints

Implementations

impl UserId

pub fn new(user_id: String) -> Result<Self, PipelineError>

Creates a new user ID with format validation

Purpose

Creates a type-safe user identifier with comprehensive format validation. Supports email, username, UUID, and system account formats.

Why

Type-safe user IDs provide:

• Prevention of authentication errors from invalid formats
• Clear API contracts for authentication systems
• Audit trail support with validated identities
• Domain-based authorization capabilities

Arguments

• user_id - User identifier string (email, username, UUID, or system)

Returns

• Ok(UserId) - Valid user ID
• Err(PipelineError::InvalidConfiguration) - Invalid format

Errors

Returns error when:

• User ID is empty
• User ID exceeds 256 characters
• Contains invalid characters

Examples

pub fn parse(user_id: &str) -> Result<Self, PipelineError>

Creates a user ID from a string slice

pub fn value(&self) -> &str

Gets the user ID string

pub fn is_email(&self) -> bool

Checks if this is an email format user ID

pub fn is_username(&self) -> bool

Checks if this is a username format user ID

pub fn is_uuid(&self) -> bool

Checks if this is a UUID format user ID

pub fn email_domain(&self) -> Option<&str>

Gets the domain from email format user ID

pub fn email_local(&self) -> Option<&str>

Gets the local part from email format user ID

pub fn belongs_to_domain(&self, domain: &str) -> bool

Checks if user belongs to a specific domain

Purpose

Validates user’s email domain for domain-based authorization. Used for multi-tenant access control and organization filtering.

Why

Domain-based authorization enables:

• Multi-tenant access control
• Organization-level permissions
• Domain-specific feature access
• Email-based user grouping

Arguments

• domain - Domain to check (case-insensitive)

Returns

true if user’s email domain matches (case-insensitive), false otherwise

Examples

pub fn is_system_user(&self) -> bool

Checks if this is a system user account

Purpose

Identifies service accounts and system users for special handling. System users typically have elevated permissions and different audit requirements.

Why

System user detection enables:

• Service account identification
• Automated process authentication
• Different authorization rules
• Separate audit logging

Returns

true if user ID starts with: system-, service-, bot-, or api-

Examples

pub fn is_admin_user(&self) -> bool

Checks if this is an admin user (contains ‘admin’ or ends with ‘-admin’)

pub fn user_type(&self) -> UserType

Gets the user type based on format and content

pub fn validate(&self) -> Result<(), PipelineError>

Validates the user ID

pub fn normalize(&self) -> UserId

Normalizes the user ID (lowercase for emails)

impl UserId

Predefined user ID builders

pub fn email(email: &str) -> Result<Self, PipelineError>

Creates an email-based user ID

pub fn username(username: &str) -> Result<Self, PipelineError>

Creates a username-based user ID

pub fn uuid(uuid: &str) -> Result<Self, PipelineError>

Creates a UUID-based user ID

pub fn system(name: &str) -> Result<Self, PipelineError>

Creates a system user ID

pub fn api(name: &str) -> Result<Self, PipelineError>

Creates an API user ID

Trait Implementations

impl AsRef<str> for UserId

fn as_ref(&self) -> &str

Converts this type into a shared reference of the (usually inferred) input type.

impl Clone for UserId

fn clone(&self) -> UserId

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for UserId

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for UserId

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl From<UserId> for String

fn from(user_id: UserId) -> Self

Converts to this type from the input type.

impl FromStr for UserId

type Err = PipelineError

The associated error which can be returned from parsing.

fn from_str(s: &str) -> Result<Self, Self::Err>

Parses a string s to return a value of this type.

impl Hash for UserId

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for UserId

fn cmp(&self, other: &UserId) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for UserId

fn eq(&self, other: &UserId) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for UserId

fn partial_cmp(&self, other: &UserId) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Eq for UserId

impl StructuralPartialEq for UserId