Utilities

Utility functions and helpers provided by NestJS CRUD Automator.

Entity Utilities

GenerateEntityInformation

Generates entity metadata from entity class.

Location: src/utility/generate-entity-information.utility.ts

function GenerateEntityInformation<E>(entity: Type<E>): IApiEntity<E>

Usage:

const entityInfo = GenerateEntityInformation(UserEntity);
// Returns: { name: "UserEntity", primaryKey: "id", columns: [...], relations: [...] }

getEntityColumns

Gets all column names from an entity.

Location: src/utility/get-entity-columns.utility.ts

function getEntityColumns<E>(entity: Type<E>): string[]

DTO Utilities

analyzeEntityMetadata

Analyzes entity metadata for DTO generation.

Location: src/utility/dto/analize.utility.ts

function analyzeEntityMetadata<E>(entity: Type<E>): void

Internal Use: Called automatically by controller factory.

DtoGenerate

Generates DTO classes from entity metadata.

Location: src/utility/dto/generate.utility.ts

function DtoGenerate(/* parameters */): Type<any>

Internal Use: Called automatically for DTO generation.

String Utilities

camelCaseString

Converts string to camelCase.

Location: src/utility/camel-case-string.utility.ts

function camelCaseString(input: string): string

Example:

camelCaseString("user_name") // Returns: "userName"
camelCaseString("UserName") // Returns: "userName"

capitalizeString

Capitalizes first letter of string.

Location: src/utility/capitalize-string.utility.ts

function capitalizeString(input: string): string

Example:

capitalizeString("hello") // Returns: "Hello"

Error Utilities

ErrorException

Creates formatted error messages.

Location: src/utility/error-exception.utility.ts

function ErrorException(message: string, context?: any): Error

Example:

throw ErrorException("Invalid entity configuration", {
  entity: "UserEntity",
  field: "id"
});

errorString

Formats error objects to strings.

Location: src/utility/error-string.utility.ts

function errorString(error: unknown): string

isErrorOfType

Checks if error is of specific type.

Location: src/utility/is-error-of-type.utility.ts

function isErrorOfType<T extends Error>(
  error: unknown,
  errorType: Type<T>
): error is T

Example:

if (isErrorOfType(error, ValidationError)) {
  // Handle validation error
}

Logging Utilities

LoggerUtility

Logging utility for internal use.

Location: src/utility/logger.utility.ts

class LoggerUtility {
  static log(message: string, context?: string): void
  static error(message: string, trace?: string, context?: string): void
  static warn(message: string, context?: string): void
  static debug(message: string, context?: string): void
}

Example:

LoggerUtility.log("Operation completed", "UserService");
LoggerUtility.error("Operation failed", error.stack, "UserService");

Controller Utilities

ApiControllerApplyDecorators

Applies decorators to controller methods.

Location: src/utility/api/controller/apply-decorators.utility.ts

Internal Use: Used by controller factory.

ApiControllerApplyMetadata

Applies metadata to controller methods.

Location: src/utility/api/controller/apply-metadata.utility.ts

Internal Use: Used by controller factory.

ApiControllerGetMethodName

Gets method name for route type.

Location: src/utility/api/controller/get-method-name.utility.ts

Internal Use: Used by controller factory.

ApiControllerGetPrimaryColumn

Gets primary column from entity.

Location: src/utility/api/controller/get-primary-column.utility.ts

function ApiControllerGetPrimaryColumn<E>(
  entity: Type<E>
): IApiControllerPrimaryColumn

ApiControllerHandleRequestRelations

Handles relation loading in requests.

Location: src/utility/api/controller/handle-request-relations.utility.ts

Internal Use: Used by controller factory.

ApiControllerTransformData

Transforms request/response data.

Location: src/utility/api/controller/transform-data.utility.ts

Internal Use: Used by controller factory.

ApiControllerValidateRequest

Validates incoming requests.

Location: src/utility/api/controller/validate-request.utility.ts

Internal Use: Used by controller factory.

ApiControllerWriteDtoSwagger

Writes Swagger documentation for DTOs.

Location: src/utility/api/controller/write-dto-swagger.utility.ts

Internal Use: Used by controller factory.

ApiControllerWriteMethod

Writes controller methods.

Location: src/utility/api/controller/write-method.utility.ts

Internal Use: Used by controller factory.

Filter Utilities

ApiControllerGetListTransformFilter

Transforms filter query parameters.

Location: src/utility/api/controller/get-list/transform-filter.utility.ts

Internal Use: Used for query parameter transformation.

ApiControllerGetListTransformOperation

Transforms filter operations.

Location: src/utility/api/controller/get-list/transform-operation.utility.ts

Internal Use: Used for filter operation mapping.

filterOrderByFromEntity

Generates order by options from entity.

Location: src/utility/api/filter-order-by-from-entity.utility.ts

Internal Use: Used for sorting configuration.

Next Steps

• Validators - Custom validators
• Interceptors - Interceptors reference
• Classes - Base classes