eslint-plugin-kysely

eslint-plugin-kysely is a fork of eslint-plugin-kysely-rules.

ESLint plugin for enforcing safe database operations with Kysely. This plugin helps prevent common SQL-related issues and enforces best practices when working with Kysely.

Features

• Enforces WHERE clauses to prevent accidental full table scans
• Ensures SELECT clauses are explicitly defined
• Prevents ambiguous column references in queries
• Additional rules for safe database operations

Installation

npm install --save-dev eslint-plugin-kysely

Configuration

Basic Configuration

Add the plugin to your ESLint configuration:

{
  "plugins": ["kysely"],
  "rules": {
    "kysely/enforce-where-clause": "error",
    "kysely/enforce-select-clause": "warn",
    "kysely/enforce-no-ambigious-columns": "error",
    "kysely/enforce-kysely-operators": "warn"
  }
}

Recommended Configuration

For the best experience, you can use the recommended configuration which enables all rules with sensible defaults:

{
  "extends": ["plugin:kysely/recommended"]
}

This is equivalent to:

{
  "plugins": ["kysely"],
  "rules": {
    "kysely/enforce-where-clause": "error",
    "kysely/enforce-select-clause": "warn",
    "kysely/enforce-no-ambigious-columns": "error",
    "kysely/enforce-kysely-operators": "warn"
  }
}

Available Rules

enforce-where-clause

Prevents queries without WHERE clauses to avoid accidental table drops.

// ❌ Bad
db.deleteFrom("users");

// ✅ Good
db.deleteFrom("users").where("id", "=", 1);

enforce-select-clause

Ensures that SELECT clauses are explicitly defined`.

// ❌ Bad
db.selectFrom("users");

// ✅ Good
db.selectFrom("users").select(["id", "name", "email"]);

enforce-no-ambigious-columns

Prevents ambiguous column references in JOIN queries.

// ❌ Bad
db.selectFrom("users")
  .innerJoin("posts", "users.id", "posts.user_id")
  .select("id"); // Ambiguous: which table's id?

// ✅ Good
db.selectFrom("users")
  .innerJoin("posts", "users.id", "posts.user_id")
  .select(["users.id", "posts.id"]);

enforce-kysely-operators

Enforces proper operator usage in Kysely queries, particularly for null comparisons and array operations.

// ❌ Bad
db.selectFrom("users").where("deleted_at", "=", null);

db.selectFrom("users").where("status", "=", ["active", "pending"]);

// ✅ Good
db.selectFrom("users").where("deleted_at", "is", null);

db.selectFrom("users").where("status", "in", ["active", "pending"]);

The rule enforces:

• Using is and is not instead of = and != when comparing with null
• Using in instead of = when comparing with arrays

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

ISC

Author

sasumaki