@flowblade/source-kysely

A source adapter for Kysely.


Install

``bash
yarn add @flowblade/source-kysely kysely

Install optional drivers

01. for Ms SqlServer or Azure Sql Edge

yarn add tedious tarn
`

Kysely supports


Quick start

`typescript
// Your db configuration, see Utils section for more details
import { db } from "@/config/db.config.ts";
import { KyselyDatasource, isQueryResultError } from "@flowblade/source-kysely";
import { sql } from "kysely";

import { KyselyDatasource, isQueryResultError } from "@flowblade/source-kysely";

const ds = new KyselyDatasource({ db });
const query = ds.queryBuilder // This gives access to Kysely expression builder
.selectFrom("brand as b")
.select(["b.id", "b.name"])
.leftJoin("product as p", "p.brand_id", "b.id")
.select(["p.id as product_id", "p.name as product_name"])
.where("b.created_at", "<", new Date())
.orderBy("b.name", "desc");

const result = await ds.query(query);

// Or with query information (will be sent in the metadata)
// const result = await ds.query(query, {
// name: 'getBrands'
// });

// Option 1: the QResult object contains the data, metadata and error
// - data: the result rows (TData or undefined if error)
// - error: the error (QError or undefined if success)
// - meta: the metadata (always present)

const { data, meta, error } = result;

// Option 2: You operate over the result, ie: mapping the data

const { data: data2 } = result.map((row) => {
return {
...data,
key: key-${row.productId},
};
});
`

$3

`typescript
import { KyselyDatasource } from "@flowblade/source-kysely";

const ds = new KyselyDatasource({ db });
const query = ds.queryBuilder // This gives access to Kysely expression builder
.selectFrom("brand as b")
.select(["b.id", "b.name"]);

const stream = ds.stream(query, {
// Chunksize used when reading the database
// @default undefined
chunkSize: undefined,
});

for await (const brand of stream) {
console.log(brand.name);
if (brand.name === "Something") {
// Breaking or returning before the stream has ended will release
// the database connection and invalidate the stream.
break;
}
}
`

Utils

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Create a Kysely dialect for Ms SqlServer or Azure Sql Edge.

`typescript
import * as Tedious from "tedious";
import {
TediousConnUtils,
createKyselyMssqlDialect,
} from "@flowblade/source-kysely";

const jdbcDsn =
"sqlserver://localhost:1433;database=db;user=sa;password=pwd;trustServerCertificate=true;encrypt=false";
const tediousConfig = TediousConnUtils.fromJdbcDsn(jdbcDsn);

const dialect = createKyselyMssqlDialect({
tediousConfig,
// 👉 Optional tarn pool options
poolOptions: {
min: 0, // 👉 Minimum number of connections, default 0
max: 10, // 👉 Maximum number of connections, default 10
propagateCreateError: true, // 👉 Propagate connection creation errors, default false
},
dialectConfig: {
/**
* When true, connections are validated before being acquired from the pool,
* resulting in additional requests to the database.
*
* In safe scenarios, this can be set to false to improve performance.
*
* Defaults to true.
*/
validateConnections: true,
/**
* When true, connections are reset to their initial states when released back to the pool,
* resulting in additional requests to the database.
*
* Defaults to false.
*/
resetConnectionsOnRelease: false,
// 👉 Override Tedious types to enhance compatibility and modern support
tediousTypes: {
...Tedious.TYPES,
// see https://github.com/kysely-org/kysely/issues/1161#issuecomment-2384539764
NVarChar: Tedious.TYPES.VarChar,
// see https://github.com/kysely-org/kysely/issues/1596#issuecomment-3341591075
DateTime: Tedious.TYPES.DateTime2,
},
},
});

const db = new Kysely({
dialect,
});
`

> Note: For performance you can avoid connection roundtrips by setting validateConnections to false
> and resetConnectionOnRelease to false.

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#### fromJdbcDsn

Parse and validate a JDBC connection string and return a Tedious connection configuration.

`typescript
import * as Tedious from "tedious";
import { TediousConnUtils } from "@flowblade/source-kysely";

// In your .env file
// DB_JDBC_DSN="sqlserver://localhost:1433;database=db;user=sa;password=pwd;trustServerCertificate=true;encrypt=false";

const tediousConfig = TediousConnUtils.fromJdbcDsn(process.env.DB_JDBC_DSN);

const tediousConnection = new Tedious.Connection(tediousConfig);
``

Compatibility

| Level | CI | Description |
| ------------ | --- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Node | ✅ | CI for 20.x, 22.x. & 24.x |
| Cloudflare | ✅ | Ensured with @cloudflare/vitest-pool-workers (see wrangler.toml |
| Browserslist | ✅ | > 95% on 01/2025. Chrome 96+, Firefox 90+, Edge 19+, ios 15+, Safari 15+ and Opera 77+ |
| Typescript | ✅ | TS 5.0 + / are-the-type-wrong checks on CI. |
| ES2022 | ✅ | Dist files checked with es-check |
| Performance | ✅ | Monitored with codspeed.io |

Contributors

Contributions are welcome. Have a look to the CONTRIBUTING document.

Sponsors

Sponsor>), coffee>),
or star – All is spent for quality time with loved ones. Thanks ! 🙏❤️

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JetBrains	Embie.be

License

MIT © Sébastien Vanvelthem and contributors.