Prisma Better Errors

This module provides a way to handle errors thrown by the Prisma ORM in a more descriptive way. By default, Prisma throws errors with error codes that can be hard to understand for developers not familiar with the specific error codes used by Prisma. This module maps Prisma error codes to error messages and HTTP status codes, making it easier for developers to understand what went wrong and return appropriate error responses in their APIs.

Installation

You can install this module using npm:

npm install prisma-better-errors

Usage

To use this module, you need to import the prismaError class and use it to catch Prisma errors in your code. Here's an example:

import { PrismaClient,Prisma } from '@prisma/client';
import {  prismaError } from './prisma';

const prisma = new PrismaClient();

async function main() {
  try {
    const user = await prisma.user.create({
      data: {
        name: 'Alice',
        email: '[email protected]',
      },
    });
    console.log(user);
  } catch (error:any) {
    if (error instanceof Prisma.PrismaClientKnownRequestError) {
      console.log('HERE');
      throw new prismaError(error);
    }
    throw error
  }
}

main()
  .then(async () => {
    await prisma.$disconnect();
  })
  .catch(async (e) => {
    console.error(e);
    await prisma.$disconnect();
    process.exit(1);
  });
}

In this example, the getUser function tries to fetch a user from the database using Prisma's findUnique method. If an error is thrown, the prismaError class is used to wrap the error and provide a more descriptive error message and HTTP status code.

The prismaError class extends the built-in Error class and adds three properties:

• message: the error message.
• statusCode: the HTTP status code to return in the API response.
• metaData (optional): an object containing additional metadata about the error. This can be useful for debugging purposes.

With express middleware

Add the prismaError class to your error handling middleware and return the statusCode and title properties as part of the API error response. The metaData property can also be returned if it contains any additional information about the error.

app.use((err, req, res, next) => {
  if (err instanceof prismaError) {
    res.status(err.statusCode).json({
      title: err.title,
      message: err.message,
      metaData: err.metaData,
    });
  } else {
    // Handle other errors here
  }
});

// response
{
    "title": "Prisma Error",
    "statusCode": 409,
    "message": "Unique constraint failed",
    "metaData": {
        "target": [
            "email"
        ]
    }
}

Custom Error Messages

You can customize the error message and HTTP status code for each Prisma error code by modifying the QueryError map in the prisma-better-errors module. For example:

import { QueryError, prismaError } from 'prisma-better-errors';

// Add a new error code mapping
QueryError.set('P3000', { message: 'My custom error message', httpStatus: 422 });

// Use the new error code in your code
try {
  // Prisma code here
} catch (error) {
  // these are the query errors
  if (error instanceof Prisma.PrismaClientKnownRequestError) {
    throw new prismaError(error);
  }
}

Error Codes

The following table lists the error codes and their corresponding error messages and HTTP status codes:

| Error Code | Message | HTTP Status Code | | ---------- | ---------------------------------------------------------------------------------------------- | ---------------- | | P2000 | The provided value for the column is too long for the column's type | 400 | | P2001 | The record searched for in the where condition does not exist | 404 | | P2002 | Unique constraint failed | 409 | | P2003 | Foreign key constraint failed | 409 | | P2004 | A constraint failed on the database | 400 | | P2005 | The value stored in the database for the field is invalid for the field's type | 400 | | P2006 | The provided value for the field is not valid | 400 | | P2007 | Data validation error | 400 | | P2008 | Failed to parse the query | 400 | | P2009 | Failed to validate the query | 400 | | P2010 | Raw query failed | 500 | | P2011 | Null constraint violation | 400 | | P2012 | Missing a required value | 400 | | P2013 | Missing a required argument | 400 | | P2014 | The change you are trying to make would violate the required relation | 400 | | P2015 | A related record could not be found | 404 | | P2016 | Query interpretation error | 400 | | P2017 | The records for relation between the parent and child models are not connected | 400 | | P2018 | The required connected records were not found | 404 | | P2019 | Input error | 400 | | P2020 | Value out of range for the type | 400 | | P2021 | The table does not exist in the current database | 404 | | P2022 | The column does not exist in the current database | 404 | | P2023 | Inconsistent column data | 400 | | P2024 | Timed out fetching a new connection from the pool | 500 | | P2025 | An operation failed because it depends on one or more records that were required but not found | 404 | | P2026 | The current database provider doesn't support a feature that the query used | 400 | | P2027 | Multiple errors occurred on the database during query execution | 500 |

Author

Youssef Hany

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