idGenerator.ts•9.63 kB
/**
* @fileoverview Provides a utility class `IdGenerator` for creating customizable, prefixed unique identifiers,
* and a standalone `generateUUID` function for generating standard UUIDs.
* The `IdGenerator` supports entity-specific prefixes, custom character sets, and lengths.
*
* Note: Logging has been removed from this module to prevent circular dependencies
* with the `requestContextService`, which itself uses `generateUUID` from this module.
* This was causing `ReferenceError: Cannot access 'generateUUID' before initialization`
* during application startup.
* @module src/utils/security/idGenerator
*/
import { randomUUID as cryptoRandomUUID, randomBytes } from "crypto";
import { BaseErrorCode, McpError } from "../../types-global/errors.js";
// Removed: import { logger, requestContextService } from "../index.js";
/**
* Defines the structure for configuring entity prefixes.
* Keys are entity type names (e.g., "project", "task"), and values are their corresponding ID prefixes (e.g., "PROJ", "TASK").
*/
export interface EntityPrefixConfig {
[key: string]: string;
}
/**
* Defines options for customizing ID generation.
*/
export interface IdGenerationOptions {
length?: number;
separator?: string;
charset?: string;
}
/**
* A generic ID Generator class for creating and managing unique, prefixed identifiers.
* Allows defining custom prefixes, generating random strings, and validating/normalizing IDs.
*/
export class IdGenerator {
/**
* Default character set for the random part of the ID.
* @private
*/
private static DEFAULT_CHARSET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
/**
* Default separator character between prefix and random part.
* @private
*/
private static DEFAULT_SEPARATOR = "_";
/**
* Default length for the random part of the ID.
* @private
*/
private static DEFAULT_LENGTH = 6;
/**
* Stores the mapping of entity types to their prefixes.
* @private
*/
private entityPrefixes: EntityPrefixConfig = {};
/**
* Stores a reverse mapping from prefixes (case-insensitive) to entity types.
* @private
*/
private prefixToEntityType: Record<string, string> = {};
/**
* Constructs an `IdGenerator` instance.
* @param entityPrefixes - An initial map of entity types to their prefixes.
*/
constructor(entityPrefixes: EntityPrefixConfig = {}) {
// Logging removed to prevent circular dependency with requestContextService.
this.setEntityPrefixes(entityPrefixes);
}
/**
* Sets or updates the entity prefix configuration and rebuilds the internal reverse lookup map.
* @param entityPrefixes - A map where keys are entity type names and values are their desired ID prefixes.
*/
public setEntityPrefixes(entityPrefixes: EntityPrefixConfig): void {
// Logging removed.
this.entityPrefixes = { ...entityPrefixes };
this.prefixToEntityType = Object.entries(this.entityPrefixes).reduce(
(acc, [type, prefix]) => {
acc[prefix.toLowerCase()] = type; // Store lowercase for case-insensitive lookup
return acc;
},
{} as Record<string, string>,
);
}
/**
* Retrieves a copy of the current entity prefix configuration.
* @returns The current entity prefix configuration.
*/
public getEntityPrefixes(): EntityPrefixConfig {
return { ...this.entityPrefixes };
}
/**
* Generates a cryptographically secure random string.
* @param length - The desired length of the random string. Defaults to `IdGenerator.DEFAULT_LENGTH`.
* @param charset - The character set to use. Defaults to `IdGenerator.DEFAULT_CHARSET`.
* @returns The generated random string.
*/
public generateRandomString(
length: number = IdGenerator.DEFAULT_LENGTH,
charset: string = IdGenerator.DEFAULT_CHARSET,
): string {
const bytes = randomBytes(length);
let result = "";
for (let i = 0; i < length; i++) {
result += charset[bytes[i] % charset.length];
}
return result;
}
/**
* Generates a unique ID, optionally prepended with a prefix.
* @param prefix - An optional prefix for the ID.
* @param options - Optional parameters for ID generation (length, separator, charset).
* @returns A unique identifier string.
*/
public generate(prefix?: string, options: IdGenerationOptions = {}): string {
// Logging removed.
const {
length = IdGenerator.DEFAULT_LENGTH,
separator = IdGenerator.DEFAULT_SEPARATOR,
charset = IdGenerator.DEFAULT_CHARSET,
} = options;
const randomPart = this.generateRandomString(length, charset);
const generatedId = prefix
? `${prefix}${separator}${randomPart}`
: randomPart;
return generatedId;
}
/**
* Generates a unique ID for a specified entity type, using its configured prefix.
* @param entityType - The type of entity (must be registered).
* @param options - Optional parameters for ID generation.
* @returns A unique identifier string for the entity (e.g., "PROJ_A6B3J0").
* @throws {McpError} If the `entityType` is not registered.
*/
public generateForEntity(
entityType: string,
options: IdGenerationOptions = {},
): string {
const prefix = this.entityPrefixes[entityType];
if (!prefix) {
throw new McpError(
BaseErrorCode.VALIDATION_ERROR,
`Unknown entity type: ${entityType}. No prefix registered.`,
);
}
return this.generate(prefix, options);
}
/**
* Validates if an ID conforms to the expected format for a specific entity type.
* @param id - The ID string to validate.
* @param entityType - The expected entity type of the ID.
* @param options - Optional parameters used during generation for validation consistency.
* @returns `true` if the ID is valid, `false` otherwise.
*/
public isValid(
id: string,
entityType: string,
options: IdGenerationOptions = {},
): boolean {
const prefix = this.entityPrefixes[entityType];
const {
length = IdGenerator.DEFAULT_LENGTH,
separator = IdGenerator.DEFAULT_SEPARATOR,
} = options;
if (!prefix) {
return false;
}
// Assumes default charset characters (uppercase letters and digits) for regex.
const pattern = new RegExp(
`^${this.escapeRegex(prefix)}${this.escapeRegex(separator)}[A-Z0-9]{${length}}$`,
);
return pattern.test(id);
}
/**
* Escapes special characters in a string for use in a regular expression.
* @param str - The string to escape.
* @returns The escaped string.
* @private
*/
private escapeRegex(str: string): string {
return str.replace(/[.*+?^${}()|[\]\\]/g, "\\$&");
}
/**
* Strips the prefix and separator from an ID string.
* @param id - The ID string (e.g., "PROJ_A6B3J0").
* @param separator - The separator used in the ID. Defaults to `IdGenerator.DEFAULT_SEPARATOR`.
* @returns The ID part without the prefix, or the original ID if separator not found.
*/
public stripPrefix(
id: string,
separator: string = IdGenerator.DEFAULT_SEPARATOR,
): string {
const parts = id.split(separator);
return parts.length > 1 ? parts.slice(1).join(separator) : id; // Handle separators in random part
}
/**
* Determines the entity type from an ID string by its prefix (case-insensitive).
* @param id - The ID string (e.g., "PROJ_A6B3J0").
* @param separator - The separator used in the ID. Defaults to `IdGenerator.DEFAULT_SEPARATOR`.
* @returns The determined entity type.
* @throws {McpError} If ID format is invalid or prefix is unknown.
*/
public getEntityType(
id: string,
separator: string = IdGenerator.DEFAULT_SEPARATOR,
): string {
const parts = id.split(separator);
if (parts.length < 2 || !parts[0]) {
throw new McpError(
BaseErrorCode.VALIDATION_ERROR,
`Invalid ID format: ${id}. Expected format like: PREFIX${separator}RANDOMLPART`,
);
}
const prefix = parts[0];
const entityType = this.prefixToEntityType[prefix.toLowerCase()];
if (!entityType) {
throw new McpError(
BaseErrorCode.VALIDATION_ERROR,
`Unknown entity type for prefix: ${prefix}`,
);
}
return entityType;
}
/**
* Normalizes an entity ID to ensure the prefix matches the registered case
* and the random part is uppercase.
* @param id - The ID to normalize (e.g., "proj_a6b3j0").
* @param separator - The separator used in the ID. Defaults to `IdGenerator.DEFAULT_SEPARATOR`.
* @returns The normalized ID (e.g., "PROJ_A6B3J0").
* @throws {McpError} If the entity type cannot be determined from the ID.
*/
public normalize(
id: string,
separator: string = IdGenerator.DEFAULT_SEPARATOR,
): string {
const entityType = this.getEntityType(id, separator);
const registeredPrefix = this.entityPrefixes[entityType];
const idParts = id.split(separator);
const randomPart = idParts.slice(1).join(separator);
return `${registeredPrefix}${separator}${randomPart.toUpperCase()}`;
}
}
/**
* Default singleton instance of the `IdGenerator`.
* Initialize with `idGenerator.setEntityPrefixes({})` to configure.
*/
export const idGenerator = new IdGenerator();
/**
* Generates a standard Version 4 UUID (Universally Unique Identifier).
* Uses the Node.js `crypto` module. This function is independent of the IdGenerator instance
* to prevent circular dependencies when used by other utilities like requestContextService.
* @returns A new UUID string.
*/
export const generateUUID = (): string => {
return cryptoRandomUUID();
};