Sequelize paranoid delete cascade

models.js

import paranoidDeleteCascade from './helpers/paranoidDeleteCascade';

// Patch the paranoid delete functionality of Sequelize
sequelize.addHook('afterDestroy', paranoidDeleteCascade(db));

paranoid-delete-cascade.js

import isArray from 'lodash/isArray';
import map from 'lodash/map';

const paranoidDeleteCascade = (models) =>
  async (instance, options, next) => {
    // Only operate on paranoid models
    if (!instance.$modelOptions.paranoid) {
      return next();
    }

    const modelName = instance.$modelOptions.name.singular;

    await Promise.all(
      // Go over all associations of the instance model, and delete if needed
      map(models[modelName].associations, async (association) => {
        try {
          // Only delete if cascade is set up correctly
          if (association.options.onDelete !== 'CASCADE') {
            return true;
          }

          let relationModel = association.target;

          const getOptions = { transaction: options.transaction };

          // Handle "through" cases
          if (association.through) {
            relationModel = association.through.model;

            // Include the id of the through model instance
            getOptions.include = [{
              model: relationModel,
            }];
          }

          // Load id(s) of association
          const instances = await instance[`get${association.as}`](getOptions);

          if (isArray(instances)) {
            // Association has no results so nothing to delete
            if (instances.length === 0) {
              return true;
            }

            // Delete all individually as bulk delete doesn't cascase in sequelize
            return await Promise.all(instances.map(i => i.destroy(Object.assign({}, options, { individualHooks: true }))));
          }

          // Association is not set, so nothing to delete
          if (!instances) {
            return true;
          }

          return await instances.destroy(options);
        } catch (error) {
          // If we had issues deleting, we have bigger problems
          Promise.resolve(true);
        }

        return true;
      })
    );

    return next();
  };

export default paranoidDeleteCascade;

Transactions also need to be passed to the helper that load associations.

const getOptions = { transaction: options.transaction };

Sorry, how can i use that. I tried to mount it like this:

import paranoidDeleteCascade from "./paranoidDeleteCascade";

const Sequelize = require("sequelize");
require("dotenv").config();

export const sequelizeConnection = new Sequelize(
  process.env.DB_NAME,
  process.env.DB_USER,
  process.env.DB_PASSWORD,
  {
    port: process.env.DB_PORT,
    host: process.env.DB_HOST, //change this with docker host
    dialect: process.env.DB_DIALECT
  }
);

sequelizeConnection.addHook("afterDestroy", paranoidDeleteCascade(sequelizeConnection));

is that okei ? It seems not to work

Here an example of association

ProductPrice.belongsTo(Product, {
  foreignKey: "productId",
  onDelete: "CASCADE",
  hooks: "true"
});

Product.hasMany(ProductPrice, {
  as: "productPrices",
  onDelete: "CASCADE",
  hooks: true,
  constraints: true
});

@Christian-Nja, on this line, you need to pass an object containing yours models to paranoidDeleteCascade.

sequelizeConnection.addHook("afterDestroy", paranoidDeleteCascade(models));

@AntoineGrandchamp thank you! I inserted my model like this:

sequelizeConnection.addHook("afterDestroy",  paranoidDeleteCascade({
    product: Product,
    productDescription: ProductDescription,
  })
);

the relations are:

ProductDescription.belongsTo(Product, {
  foreignKey: "productId"
});

Product.hasMany(ProductDescription, {
  as: "productDescriptions",
  onDelete: "CASCADE",
  hooks: true
});

And the models:

const Sequelize = require("sequelize");
import { sequelizeConnection } from "../mySqlDBConnection";

export const Product = sequelizeConnection.define(
  "product",
  {
    id: {
      defaultValue: Sequelize.UUIDV4,
      type: Sequelize.UUIDV4,
      primaryKey: true,
      allowNull: false
    },
    shopCode: {
      type: Sequelize.STRING,
      allowNull: false
    },
    name: {
      type: Sequelize.STRING,
      allowNull: false
    },
    barCode: {
      type: Sequelize.STRING
    },
    quantity: {
      type: Sequelize.INTEGER,
      allowNull: false
    },
    state: {
      type: Sequelize.STRING,
      allowNull: false
    },
    deleteReason: {
      type: Sequelize.STRING
    }
  },
  {
    tableName: "product",
    freezeTableName: true,
    paranoid: true,
    timestamps: true
  },
  {
    indexes: [
      {
        unique: true,
        fields: ["id", "barCode", "shopCode"]
      }
    ]
  }
);

const Sequelize = require("sequelize");
import { sequelizeConnection } from "../mySqlDBConnection";

export const ProductDescription = sequelizeConnection.define(
  "product_description",
  {
    id: {
      defaultValue: Sequelize.UUIDV4,
      type: Sequelize.UUIDV4,
      primaryKey: true,
      allowNull: false
    },
    description: {
      type: Sequelize.STRING
    },
    importance: {
      type: Sequelize.INTEGER
    },
    productId: {
      type: Sequelize.INTEGER
    },
    deleteReason: {
      type: Sequelize.STRING
    }
  },
  {
    tableName: "product_description",
    freezeTableName: true,
    paranoid: true,
    timestamps: true
  },
  {
    indexes: [
      {
        unique: true,
        fields: ["id"]
      }
    ]
  }
);

But it still doesn't work ...

I confirm that this does work, great idea man, it might put some load on your server though specially if you're soft deleting large amount of data with a lot of associations.
One hint though, you need to the "individualHooks: true," property to the destroy options for the "afterDestroy" hook to run, otherwise it'll the "afterDestroy" won't fire but the "afterBulkDestroy" will fire instead.
I'm using sequelize version 5.22.3.
await db[model].destroy({ where: { id: item.id }, transaction: transaction, individualHooks: true, });

Thanks for the feedback @gostavee and @AntoineGrandchamp . I've incorporated your suggestions.