Source

repository/BaseRepository.ts

import { IRepository } from "../interfaces/IRepository";
import { Constructor, Model } from "@decaf-ts/decorator-validation";
import { enforceDBDecorators } from "./utils";
import { OperationKeys } from "../operations/constants";
import { InternalError } from "./errors";
import { wrapMethodWithContext } from "./wrappers";
import { findPrimaryKey } from "../identity/utils";
import { Context } from "./Context";
import { RepositoryFlags } from "./types";

/**
 * @description Base repository implementation providing CRUD operations for models.
 * @summary The BaseRepository class serves as a foundation for repository implementations, providing
 * abstract and concrete methods for creating, reading, updating, and deleting model instances.
 * It handles operation lifecycles including prefix and suffix operations, and enforces decorators.
 * @template M - The model type extending Model
 * @template F - The repository flags type, defaults to RepositoryFlags
 * @template C - The context type, defaults to Context<F>
 * @param {Constructor<M>} clazz - The constructor for the model class
 * @class BaseRepository
 * @example
 * class UserModel extends Model {
 *   @id()
 *   id: string;
 *
 *   @required()
 *   name: string;
 * }
 *
 * class UserRepository extends BaseRepository<UserModel> {
 *   constructor() {
 *     super(UserModel);
 *   }
 *
 *   async create(model: UserModel): Promise<UserModel> {
 *     // Implementation
 *     return model;
 *   }
 *
 *   async read(key: string): Promise<UserModel> {
 *     // Implementation
 *     return new UserModel({ id: key, name: 'User' });
 *   }
 *
 *   async update(model: UserModel): Promise<UserModel> {
 *     // Implementation
 *     return model;
 *   }
 *
 *   async delete(key: string): Promise<UserModel> {
 *     // Implementation
 *     const model = await this.read(key);
 *     return model;
 *   }
 * }
 *
 * @mermaid
 * sequenceDiagram
 *   participant C as Client
 *   participant R as Repository
 *   participant P as Prefix Methods
 *   participant D as Database
 *   participant S as Suffix Methods
 *   participant V as Validators/Decorators
 *
 *   Note over C,V: Create Operation
 *   C->>R: create(model)
 *   R->>P: createPrefix(model)
 *   P->>V: enforceDBDecorators(ON)
 *   P->>D: Database operation
 *   D->>S: createSuffix(model)
 *   S->>V: enforceDBDecorators(AFTER)
 *   S->>C: Return model
 *
 *   Note over C,V: Read Operation
 *   C->>R: read(key)
 *   R->>P: readPrefix(key)
 *   P->>V: enforceDBDecorators(ON)
 *   P->>D: Database operation
 *   D->>S: readSuffix(model)
 *   S->>V: enforceDBDecorators(AFTER)
 *   S->>C: Return model
 *
 *   Note over C,V: Update Operation
 *   C->>R: update(model)
 *   R->>P: updatePrefix(model)
 *   P->>V: enforceDBDecorators(ON)
 *   P->>D: Database operation
 *   D->>S: updateSuffix(model)
 *   S->>V: enforceDBDecorators(AFTER)
 *   S->>C: Return model
 *
 *   Note over C,V: Delete Operation
 *   C->>R: delete(key)
 *   R->>P: deletePrefix(key)
 *   P->>V: enforceDBDecorators(ON)
 *   P->>D: Database operation
 *   D->>S: deleteSuffix(model)
 *   S->>V: enforceDBDecorators(AFTER)
 *   S->>C: Return model
 */
export abstract class BaseRepository<
  M extends Model,
  F extends RepositoryFlags = RepositoryFlags,
  C extends Context<F> = Context<F>,
> implements IRepository<M, F, C>
{
  private readonly _class!: Constructor<M>;
  private _pk!: keyof M;
  private _pkProps!: any;

  /**
   * @description Gets the model class constructor.
   * @summary Retrieves the constructor for the model class associated with this repository.
   * Throws an error if no class definition is found.
   * @return {Constructor<M>} The constructor for the model class
   */
  get class() {
    if (!this._class)
      throw new InternalError(`No class definition found for this repository`);
    return this._class;
  }

  /**
   * @description Gets the primary key property name of the model.
   * @summary Retrieves the name of the property that serves as the primary key for the model.
   * If not already determined, it finds the primary key using the model's decorators.
   * @return The name of the primary key property
   */
  get pk(): keyof M {
    if (!this._pk) {
      const { id, props } = findPrimaryKey(new this.class());
      this._pk = id;
      this._pkProps = props;
    }
    return this._pk;
  }

  /**
   * @description Gets the primary key properties.
   * @summary Retrieves the properties associated with the primary key of the model.
   * If not already determined, it triggers the pk getter to find the primary key properties.
   * @return {any} The properties of the primary key
   */
  protected get pkProps(): any {
    if (!this._pkProps) {
      // eslint-disable-next-line @typescript-eslint/no-unused-vars
      const pk = this.pk;
    }
    return this._pkProps;
  }

  protected constructor(clazz?: Constructor<M>) {
    if (clazz) this._class = clazz;
    // eslint-disable-next-line @typescript-eslint/no-this-alias
    const self = this;
    [this.create, this.read, this.update, this.delete].forEach((m) => {
      const name = m.name;
      wrapMethodWithContext(
        self,
        (self as any)[name + "Prefix"],
        m,
        (self as any)[name + "Suffix"]
      );
    });
  }

  /**
   * @description Creates a new model instance in the repository.
   * @summary Persists a new model instance to the underlying data store.
   * This method must be implemented by concrete repository classes.
   * @param {M} model - The model instance to create
   * @param {any[]} args - Additional arguments for the create operation
   * @return {Promise<M>} A promise that resolves to the created model instance
   */
  abstract create(model: M, ...args: any[]): Promise<M>;

  /**
   * @description Creates multiple model instances in the repository.
   * @summary Persists multiple model instances to the underlying data store by calling
   * the create method for each model in the array.
   * @param {M[]} models - The array of model instances to create
   * @param {any[]} args - Additional arguments for the create operation
   * @return {Promise<M[]>} A promise that resolves to an array of created model instances
   */
  async createAll(models: M[], ...args: any[]): Promise<M[]> {
    return Promise.all(models.map((m) => this.create(m, ...args)));
  }

  /**
   * @description Prepares a model for creation and executes pre-creation operations.
   * @summary Processes a model before it is created in the data store. This includes
   * creating a context, instantiating a new model instance, and enforcing any decorators
   * that should be applied before creation.
   * @param {M} model - The model instance to prepare for creation
   * @param {any[]} args - Additional arguments for the create operation
   * @return A promise that resolves to an array containing the prepared model and context arguments
   */
  protected async createPrefix(model: M, ...args: any[]) {
    const contextArgs = await Context.args<M, C, F>(
      OperationKeys.CREATE,
      this.class,
      args
    );
    model = new this.class(model);
    await enforceDBDecorators<M, typeof this, any, F, C>(
      this,
      contextArgs.context,
      model,
      OperationKeys.CREATE,
      OperationKeys.ON
    );
    return [model, ...contextArgs.args];
  }

  /**
   * @description Processes a model after creation and executes post-creation operations.
   * @summary Finalizes a model after it has been created in the data store. This includes
   * enforcing any decorators that should be applied after creation.
   * @param {M} model - The model instance that was created
   * @param {C} context - The context for the operation
   * @return {Promise<M>} A promise that resolves to the processed model instance
   */
  protected async createSuffix(model: M, context: C) {
    await enforceDBDecorators<M, typeof this, any, F, C>(
      this,
      context,
      model,
      OperationKeys.CREATE,
      OperationKeys.AFTER
    );
    return model;
  }

  /**
   * @description Prepares multiple models for creation and executes pre-creation operations.
   * @summary Processes multiple models before they are created in the data store. This includes
   * creating a context, instantiating new model instances, and enforcing any decorators
   * that should be applied before creation for each model.
   * @param {M[]} models - The array of model instances to prepare for creation
   * @param {any[]} args - Additional arguments for the create operation
   * @return  A promise that resolves to an array containing the prepared models and context arguments
   */
  protected async createAllPrefix(models: M[], ...args: any[]) {
    const contextArgs = await Context.args<M, C, F>(
      OperationKeys.CREATE,
      this.class,
      args
    );
    await Promise.all(
      models.map(async (m) => {
        m = new this.class(m);
        await enforceDBDecorators<M, typeof this, any, F, C>(
          this,
          contextArgs.context,
          m,
          OperationKeys.CREATE,
          OperationKeys.ON
        );
        return m;
      })
    );
    return [models, ...contextArgs.args];
  }

  /**
   * @description Processes multiple models after creation and executes post-creation operations.
   * @summary Finalizes multiple models after they have been created in the data store. This includes
   * enforcing any decorators that should be applied after creation for each model.
   * @param {M[]} models - The array of model instances that were created
   * @param {C} context - The context for the operation
   * @return {Promise<M[]>} A promise that resolves to the array of processed model instances
   */
  protected async createAllSuffix(models: M[], context: C) {
    await Promise.all(
      models.map((m) =>
        enforceDBDecorators<M, typeof this, any, F, C>(
          this,
          context,
          m,
          OperationKeys.CREATE,
          OperationKeys.AFTER
        )
      )
    );
    return models;
  }

  /**
   * @description Retrieves a model instance from the repository by its primary key.
   * @summary Fetches a model instance from the underlying data store using its primary key.
   * This method must be implemented by concrete repository classes.
   * @param {string | number} key - The primary key of the model to retrieve
   * @param {any[]} args - Additional arguments for the read operation
   * @return {Promise<M>} A promise that resolves to the retrieved model instance
   */
  abstract read(key: string | number, ...args: any[]): Promise<M>;

  /**
   * @description Retrieves multiple model instances from the repository by their primary keys.
   * @summary Fetches multiple model instances from the underlying data store using their primary keys
   * by calling the read method for each key in the array.
   * @param {string[] | number[]} keys - The array of primary keys of the models to retrieve
   * @param {any[]} args - Additional arguments for the read operation
   * @return {Promise<M[]>} A promise that resolves to an array of retrieved model instances
   */
  async readAll(keys: string[] | number[], ...args: any[]): Promise<M[]> {
    return await Promise.all(keys.map((id) => this.read(id, ...args)));
  }

  /**
   * @description Processes a model after retrieval and executes post-read operations.
   * @summary Finalizes a model after it has been retrieved from the data store. This includes
   * enforcing any decorators that should be applied after reading.
   * @param {M} model - The model instance that was retrieved
   * @param {C} context - The context for the operation
   * @return {Promise<M>} A promise that resolves to the processed model instance
   */
  protected async readSuffix(model: M, context: C) {
    await enforceDBDecorators<M, typeof this, any, F, C>(
      this,
      context,
      model,
      OperationKeys.READ,
      OperationKeys.AFTER
    );
    return model;
  }

  /**
   * @description Prepares for reading a model and executes pre-read operations.
   * @summary Processes a key before a model is read from the data store. This includes
   * creating a context, instantiating a new model instance with the key, and enforcing any decorators
   * that should be applied before reading.
   * @param {string} key - The primary key of the model to read
   * @param {any[]} args - Additional arguments for the read operation
   * @return A promise that resolves to an array containing the key and context arguments
   */
  protected async readPrefix(key: string, ...args: any[]) {
    const contextArgs = await Context.args<M, C, F>(
      OperationKeys.READ,
      this.class,
      args
    );
    const model: M = new this.class();
    model[this.pk] = key as any;
    await enforceDBDecorators<M, typeof this, any, F, C>(
      this,
      contextArgs.context,
      model,
      OperationKeys.READ,
      OperationKeys.ON
    );
    return [key, ...contextArgs.args];
  }

  /**
   * @description Prepares for reading multiple models and executes pre-read operations.
   * @summary Processes multiple keys before models are read from the data store. This includes
   * creating a context, instantiating new model instances with the keys, and enforcing any decorators
   * that should be applied before reading for each key.
   * @param {string[] | number[]} keys - The array of primary keys of the models to read
   * @param {any[]} args - Additional arguments for the read operation
   * @return A promise that resolves to an array containing the keys and context arguments
   */
  protected async readAllPrefix(keys: string[] | number[], ...args: any[]) {
    const contextArgs = await Context.args<M, C, F>(
      OperationKeys.READ,
      this.class,
      args
    );
    await Promise.all(
      keys.map(async (k) => {
        const m = new this.class();
        m[this.pk] = k as any;
        return enforceDBDecorators<M, typeof this, any, F, C>(
          this,
          contextArgs.context,
          m,
          OperationKeys.READ,
          OperationKeys.ON
        );
      })
    );
    return [keys, ...contextArgs.args];
  }

  /**
   * @description Processes multiple models after retrieval and executes post-read operations.
   * @summary Finalizes multiple models after they have been retrieved from the data store. This includes
   * enforcing any decorators that should be applied after reading for each model.
   * @param {M[]} models - The array of model instances that were retrieved
   * @param {C} context - The context for the operation
   * @return {Promise<M[]>} A promise that resolves to the array of processed model instances
   */
  protected async readAllSuffix(models: M[], context: C) {
    await Promise.all(
      models.map((m) =>
        enforceDBDecorators<M, typeof this, any, F, C>(
          this,
          context,
          m,
          OperationKeys.READ,
          OperationKeys.AFTER
        )
      )
    );
    return models;
  }

  /**
   * @description Updates an existing model instance in the repository.
   * @summary Updates an existing model instance in the underlying data store.
   * This method must be implemented by concrete repository classes.
   * @param {M} model - The model instance to update
   * @param {any[]} args - Additional arguments for the update operation
   * @return {Promise<M>} A promise that resolves to the updated model instance
   */
  abstract update(model: M, ...args: any[]): Promise<M>;

  /**
   * @description Updates multiple model instances in the repository.
   * @summary Updates multiple model instances in the underlying data store by calling
   * the update method for each model in the array.
   * @param {M[]} models - The array of model instances to update
   * @param {any[]} args - Additional arguments for the update operation
   * @return {Promise<M[]>} A promise that resolves to an array of updated model instances
   */
  async updateAll(models: M[], ...args: any): Promise<M[]> {
    return Promise.all(models.map((m) => this.update(m, ...args)));
  }

  /**
   * @description Processes a model after update and executes post-update operations.
   * @summary Finalizes a model after it has been updated in the data store. This includes
   * enforcing any decorators that should be applied after updating.
   * @param {M} model - The model instance that was updated
   * @param {C} context - The context for the operation
   * @return {Promise<M>} A promise that resolves to the processed model instance
   */
  protected async updateSuffix(model: M, context: C) {
    await enforceDBDecorators<M, typeof this, any, F, C>(
      this,
      context,
      model,
      OperationKeys.UPDATE,
      OperationKeys.AFTER
    );
    return model;
  }

  /**
   * @description Prepares a model for update and executes pre-update operations.
   * @summary Processes a model before it is updated in the data store. This includes
   * creating a context, validating the primary key, retrieving the existing model,
   * and enforcing any decorators that should be applied before updating.
   * @param {M} model - The model instance to prepare for update
   * @param {any[]} args - Additional arguments for the update operation
   * @return A promise that resolves to an array containing the prepared model and context arguments
   */
  protected async updatePrefix(model: M, ...args: any[]) {
    const contextArgs = await Context.args<M, C, F>(
      OperationKeys.UPDATE,
      this.class,
      args
    );
    const id = model[this.pk];
    if (!id)
      throw new InternalError(
        `No value for the Id is defined under the property ${this.pk as string}`
      );
    const oldModel = await this.read(id as string);
    await enforceDBDecorators<M, typeof this, any, F, C>(
      this,
      contextArgs.context,
      model,
      OperationKeys.UPDATE,
      OperationKeys.ON,
      oldModel
    );
    return [model, ...contextArgs.args];
  }

  /**
   * @description Prepares multiple models for update and executes pre-update operations.
   * @summary Processes multiple models before they are updated in the data store. This includes
   * creating a context, instantiating new model instances, and enforcing any decorators
   * that should be applied before updating for each model.
   * @param {M[]} models - The array of model instances to prepare for update
   * @param {any[]} args - Additional arguments for the update operation
   * @return A promise that resolves to an array containing the prepared models and context arguments
   */
  protected async updateAllPrefix(models: M[], ...args: any[]) {
    const contextArgs = await Context.args<M, C, F>(
      OperationKeys.UPDATE,
      this.class,
      args
    );
    await Promise.all(
      models.map((m) => {
        m = new this.class(m);
        enforceDBDecorators<M, typeof this, any, F, C>(
          this,
          contextArgs.context,
          m,
          OperationKeys.UPDATE,
          OperationKeys.ON
        );
        return m;
      })
    );
    return [models, ...contextArgs.args];
  }

  /**
   * @description Processes multiple models after update and executes post-update operations.
   * @summary Finalizes multiple models after they have been updated in the data store. This includes
   * enforcing any decorators that should be applied after updating for each model.
   * @param {M[]} models - The array of model instances that were updated
   * @param {C} context - The context for the operation
   * @return {Promise<M[]>} A promise that resolves to the array of processed model instances
   */
  protected async updateAllSuffix(models: M[], context: C) {
    await Promise.all(
      models.map((m) =>
        enforceDBDecorators<M, typeof this, any, F, C>(
          this,
          context,
          m,
          OperationKeys.UPDATE,
          OperationKeys.AFTER
        )
      )
    );
    return models;
  }

  /**
   * @description Deletes a model instance from the repository by its primary key.
   * @summary Removes a model instance from the underlying data store using its primary key.
   * This method must be implemented by concrete repository classes.
   * @param {string | number} key - The primary key of the model to delete
   * @param {any[]} args - Additional arguments for the delete operation
   * @return {Promise<M>} A promise that resolves to the deleted model instance
   */
  abstract delete(key: string | number, ...args: any[]): Promise<M>;

  /**
   * @description Deletes multiple model instances from the repository by their primary keys.
   * @summary Removes multiple model instances from the underlying data store using their primary keys
   * by calling the delete method for each key in the array.
   * @param {string[] | number[]} keys - The array of primary keys of the models to delete
   * @param {any[]} args - Additional arguments for the delete operation
   * @return {Promise<M[]>} A promise that resolves to an array of deleted model instances
   */
  async deleteAll(keys: string[] | number[], ...args: any[]): Promise<M[]> {
    return Promise.all(keys.map((k) => this.delete(k, ...args)));
  }

  /**
   * @description Processes a model after deletion and executes post-delete operations.
   * @summary Finalizes a model after it has been deleted from the data store. This includes
   * enforcing any decorators that should be applied after deletion.
   * @param {M} model - The model instance that was deleted
   * @param {C} context - The context for the operation
   * @return {Promise<M>} A promise that resolves to the processed model instance
   */
  protected async deleteSuffix(model: M, context: C) {
    await enforceDBDecorators<M, typeof this, any, F, C>(
      this,
      context,
      model,
      OperationKeys.DELETE,
      OperationKeys.AFTER
    );
    return model;
  }

  /**
   * @description Prepares for deleting a model and executes pre-delete operations.
   * @summary Processes a key before a model is deleted from the data store. This includes
   * creating a context, retrieving the model to be deleted, and enforcing any decorators
   * that should be applied before deletion.
   * @param {any} key - The primary key of the model to delete
   * @param {any[]} args - Additional arguments for the delete operation
   * @return A promise that resolves to an array containing the key and context arguments
   */
  protected async deletePrefix(key: any, ...args: any[]) {
    const contextArgs = await Context.args<M, C, F>(
      OperationKeys.DELETE,
      this.class,
      args
    );
    const model = await this.read(key, ...contextArgs.args);
    await enforceDBDecorators<M, typeof this, any, F, C>(
      this,
      contextArgs.context,
      model,
      OperationKeys.DELETE,
      OperationKeys.ON
    );
    return [key, ...contextArgs.args];
  }

  /**
   * @description Prepares for deleting multiple models and executes pre-delete operations.
   * @summary Processes multiple keys before models are deleted from the data store. This includes
   * creating a context, retrieving the models to be deleted, and enforcing any decorators
   * that should be applied before deletion for each model.
   * @param {string[] | number[]} keys - The array of primary keys of the models to delete
   * @param {any[]} args - Additional arguments for the delete operation
   * @return A promise that resolves to an array containing the keys and context arguments
   */
  protected async deleteAllPrefix(keys: string[] | number[], ...args: any[]) {
    const contextArgs = await Context.args<M, C, F>(
      OperationKeys.DELETE,
      this.class,
      args
    );
    const models = await this.readAll(keys, ...contextArgs.args);
    await Promise.all(
      models.map(async (m) => {
        return enforceDBDecorators<M, typeof this, any, F, C>(
          this,
          contextArgs.context,
          m,
          OperationKeys.DELETE,
          OperationKeys.ON
        );
      })
    );
    return [keys, ...contextArgs.args];
  }

  /**
   * @description Processes multiple models after deletion and executes post-delete operations.
   * @summary Finalizes multiple models after they have been deleted from the data store. This includes
   * enforcing any decorators that should be applied after deletion for each model.
   * @param {M[]} models - The array of model instances that were deleted
   * @param {C} context - The context for the operation
   * @return {Promise<M[]>} A promise that resolves to the array of processed model instances
   */
  protected async deleteAllSuffix(models: M[], context: C) {
    await Promise.all(
      models.map((m) =>
        enforceDBDecorators<M, typeof this, any, F, C>(
          this,
          context,
          m,
          OperationKeys.DELETE,
          OperationKeys.AFTER
        )
      )
    );
    return models;
  }

  /**
   * @description Merges two model instances into a new instance.
   * @summary Creates a new model instance by combining properties from an old model and a new model.
   * Properties from the new model override properties from the old model if they are defined.
   * @param {M} oldModel - The original model instance
   * @param {M} model - The new model instance with updated properties
   * @return {M} A new model instance with merged properties
   */
  protected merge(oldModel: M, model: M): M {
    const extract = (model: M) =>
      Object.entries(model).reduce((accum: Record<string, any>, [key, val]) => {
        if (typeof val !== "undefined") accum[key] = val;
        return accum;
      }, {});

    return new this.class(Object.assign({}, extract(oldModel), extract(model)));
  }

  /**
   * @description Returns a string representation of the repository.
   * @summary Creates a string that identifies this repository by the name of its model class.
   * @return {string} A string representation of the repository
   */
  toString() {
    return `${this.class.name} Repository`;
  }
}