Class PostgresConnector

lib/connectors/postgres-connector.ts:24–101

  | PostgresOptionsWithURI;

export class PostgresConnector implements Connector {
  _dialect: SupportedSQLDatabaseDialect = "postgres";

  _client: PostgresClient;
  _options: PostgresOptions;
  _translator: SQLTranslator;
  _connected = false;

  /** Create a PostgreSQL connection. */
  constructor(options: PostgresOptions) {
    this._options = options;
    if ("uri" in options) {
      this._client = new PostgresClient(options.uri);
    } else {
      this._client = new PostgresClient({
        hostname: options.host,
        user: options.username,
        password: options.password,
        database: options.database,
        port: options.port ?? 5432,
      });
    }
    this._translator = new SQLTranslator(this._dialect);
  }

  async _makeConnection() {
    if (this._connected) {
      return;
    }

    await this._client.connect();
    this._connected = true;
  }

  async ping() {
    await this._makeConnection();

    try {
      const [result] = (
        await this._client.queryObject("SELECT 1 + 1 as result")
      ).rows;
      return result === 2;
    } catch {
      return false;
    }
  }

  // deno-lint-ignore no-explicit-any
  async query(queryDescription: QueryDescription): Promise<any | any[]> {
    await this._makeConnection();

    const query = this._translator.translateToQuery(queryDescription);
    const response = await this._client.queryObject(query);
    const results = response.rows as Values[];

    if (queryDescription.type === "insert") {
      return results.length === 1 ? results[0] : results;
    }