Struct CollationMapper 

pub struct CollationMapper { /* private fields */ }

Maps user locales to database-specific collation strings.

The mapper takes a global CollationConfig and database type, then translates user locales (e.g., “fr-FR”) into the appropriate database-specific collation format (e.g., “fr-FR-x-icu” for PostgreSQL with ICU).

Examples

use fraiseql_db::CollationConfig;
use fraiseql_db::{DatabaseType, collation::CollationMapper};

// PostgreSQL with ICU
let config = CollationConfig::default();
let mapper = CollationMapper::new(config.clone(), DatabaseType::PostgreSQL);
assert_eq!(mapper.map_locale("fr-FR").unwrap(), Some("fr-FR-x-icu".to_string()));

// MySQL (general collation, not locale-specific)
let mapper = CollationMapper::new(config, DatabaseType::MySQL);
assert_eq!(mapper.map_locale("fr-FR").unwrap(), Some("utf8mb4_unicode_ci".to_string()));

Implementations

impl CollationMapper

pub const fn new(config: CollationConfig, database_type: DatabaseType) -> Self

Create a new collation mapper.

Arguments

• config - Global collation configuration
• database_type - Target database type

pub fn map_locale(&self, locale: &str) -> Result<Option<String>>

Map user locale to database-specific collation string.

Arguments

• locale - User locale (e.g., “fr-FR”, “ja-JP”)

Returns

• Ok(Some(collation)) - Database-specific collation string
• Ok(None) - Use database default (no COLLATE clause)
• Err(_) - Invalid locale when strategy is Error

Errors

Returns FraiseQLError::Validation if locale is not in allowed list and on_invalid_locale is set to Error.

Examples

use fraiseql_db::CollationConfig;
use fraiseql_db::{DatabaseType, collation::CollationMapper};

let config = CollationConfig::default();
let mapper = CollationMapper::new(config, DatabaseType::PostgreSQL);

// Valid locale
let collation = mapper.map_locale("fr-FR").unwrap();
assert_eq!(collation, Some("fr-FR-x-icu".to_string()));

// Invalid locale (not in allowed list)
let result = mapper.map_locale("invalid");
assert!(result.is_ok(), "utf8 is a valid collation: {result:?}");

Errors

Returns FraiseQLError::Validation if locale is not in the allowed list and the configured InvalidLocaleStrategy is Reject.

pub const fn database_type(&self) -> DatabaseType

Get the database type this mapper is configured for.

pub const fn is_enabled(&self) -> bool

Check if collation is enabled.