This library is a lightweight Node.js client derived from node-crate
for interacting with CrateDB via its HTTP endpoint. Unlike libraries such as node-postgres
, which use the PostgreSQL wire protocol, this client communicates with CrateDB's native HTTP API.
Caution
This library is primarily a proof of concept.
While it provides basic functionality to interact with CrateDB, it is not production-ready and lacks the robustness of established libraries.
For production use, consider mature libraries like node-postgres
which leverage CrateDB's PostgreSQL compatibility. Use this client only for testing, experimentation, or if you know what you're doing. 😉
The CrateDBClient
can be configured with either environment variables or directly with an options object. Below are the configuration options, along with their default values.
Option | Type | Default Value | Description |
---|---|---|---|
user |
string |
'crate' or process.env.CRATEDB_USER |
Database user. |
password |
string or null |
'' or process.env.CRATEDB_PASSWORD |
Database password. |
host |
string |
'localhost' or process.env.CRATEDB_HOST |
Database host. |
port |
number |
4200 or process.env.CRATEDB_PORT |
Database port. |
defaultSchema |
string |
'doc' or process.env.CRATEDB_DEFAULT_SCHEMA |
Default schema for queries. |
connectionString |
string |
null |
Connection string, e.g., https://user:password@host:port/ . |
ssl |
object or null |
null |
SSL configuration; |
keepAlive |
boolean |
true |
Enables HTTP keep-alive for persistent connections. |
maxConnections |
number |
20 |
Limits the maximum number of concurrent connections. |
Alternatively, you can set these variables in your environment:
export CRATEDB_USER=crate
export CRATEDB_PASSWORD=secretpassword
export CRATEDB_HOST=my.database-server.com
export CRATEDB_PORT=4200
export CRATEDB_DEFAULT_SCHEMA=doc
To use the CrateDBClient
:
- Import the
CrateDBClient
class. - Instantiate it with your configuration options.
- Call any of the CRUD and DDL methods provided.
import { CrateDBClient } from './CrateDBClient.js';
const client = new CrateDBClient({
user: 'database-user',
password: 'secretpassword!!',
host: 'my.database-server.com',
port: 5334,
defaultSchema: 'my_schema',
keepAlive: true, // Enable persistent connections
maxConnections: 20 // Limit to 20 concurrent sockets
});
Execute a raw SQL query.
await client.executeSql('SELECT * FROM my_table';);
await client.executeSql('SELECT * FROM my_table', []);
The streamQuery
method in CrateDBClient wraps the CrateDBCursor functionality
for convenient query streaming. This method automatically manages the cursor’s
lifecycle.
Streams query results row by row using an async generator. The batchSize
determines the number of rows fetched per request (default is 100
).
for await (const row of client.streamQuery('SELECT * FROM my_table ORDER BY id', 5)) {
console.log(row); // Process each row individually
}
Insert a new row into a specified table with optional primary key conflict resolution.
tableName
: The name of the table to insert the row into.obj
: An object representing the row to insert.primaryKeys
: (Optional) An array of column names to use as primary keys for conflict resolution.
If primaryKeys
are provided, the method will handle conflicts by updating the non-primary key fields of conflicting rows. If no primaryKeys
are provided, conflicting rows will be skipped.
// Insert a row with primary key conflict resolution
await client.insert("my_table", { id: 1, column1: "value1", column2: "value2" }, ["id"]);
// Insert a row without conflict resolution
await client.insert("my_table", { id: 1, column1: "value1", column2: "value2" });
Insert multiple rows into a table with optional primary key conflict resolution.
tableName
: The name of the table to insert rows into.jsonArray
: An array of objects representing rows to insert.primaryKeys
: (Optional) An array of column names to use as primary keys for conflict resolution.
If primaryKeys
are provided, the method will handle conflicts by updating the non-primary key fields of conflicting rows. If no primaryKeys
are provided, conflicting rows will be skipped.
const bulkData = [
{ id: 1, name: "Earth", kind: "Planet", description: "A beautiful place." },
{ id: 2, name: "Mars", kind: "Planet", description: "The red planet." },
{ id: 1, name: "Earth Updated", kind: "Planet", description: "Updated description." }, // Conflict on id
];
await client.insertMany("my_table", bulkData, ["id"]);
// Conflicting row with `id: 1` will be updated instead of skipped.
await client.insertMany("my_table", bulkData);
// Conflicting rows will be skipped as no `primaryKeys` are provided.
Update rows in a table that match a WHERE clause.
await client.update('my_table', { column1: 'new_value' }, 'column2 = value2');
Delete rows from a table that match a WHERE clause.
await client.delete('my_table', 'column1 = value1');
Drop a specified table.
await client.drop('my_table');
Create a new table based on a schema definition.
await client.createTable({
my_table: {
id: 'INTEGER PRIMARY KEY',
name: 'STRING',
created_at: 'TIMESTAMP'
}
});
Create a cursor to fetch large datasets efficiently.
const cursor = client.createCursor('SELECT * FROM my_table ORDER BY id');
await cursor.open();
console.log(await cursor.fetchone()); // Fetch one record
console.log(await cursor.fetchmany(5)); // Fetch 5 records
console.log(await cursor.fetchall()); // Fetch all remaining records
await cursor.close(); // Close the cursor and commit the transaction
Creates an async generator that fetches query results in chunks of size batchSize (default is 100).
const cursor = client.createCursor('SELECT * FROM my_table ORDER BY id');
await cursor.open();
for await (const row of cursor.iterate(5)) {
console.log(row); // Process each row individually
}
await cursor.close();
Configure keepAlive for persistent connections and maxConnections to limit concurrent connections.
const client = new CrateDBClient({
user: 'database-user',
password: 'secretpassword!!',
host: 'my.database-server.com',
port: 4200,
ssl: true, // Use HTTPS
keepAlive: true, // Enable persistent connections
maxConnections: 20, // Limit to 10 concurrent sockets
defaultSchema: 'my_schema' // Default schema for queries
});
MIT License. Feel free to use and modify this library as per the terms of the license.