Save binary field with typeorm

save-binary.js

require("reflect-metadata");
const {
  EntitySchema,
  createConnection,
  Table,
  getConnection,
} = require("typeorm");
const { randomUUID } = require("crypto");

const Tag = new EntitySchema({
  name: "tags",
  columns: {
    id: {
      type: Number,
      primary: true,
    },
    serial: {
      type: Buffer,
    },
  },
});

const config = {
  type: "sqlite",
  database: "./database.sqlite",
  entities: [Tag],
};
const serial = randomUUID();

console.log(`Generated uuid: ${serial}`);

createConnection(config)
  .then((conn) =>
    // create table "tags" if not exists
    conn.createQueryRunner().createTable(
      new Table({
        name: "tags",
        columns: [
          {
            name: "id",
            type: "int",
            isPrimary: true,
          },
          {
            name: "serial",
            type: "binary(16)",
          },
        ],
      }),
      true
    )
  )
  .then(() =>
    // Save tag
    getConnection()
      .getRepository(Tag)
      .save({
        id: Date.now(),
        serial: Buffer.from(serial.replace(/-/gi, ""), "hex"), // parse to buffer before save
      })
  )
  .then((saved) => {
    console.log("saved tag", saved);
    return saved;
  })
  // Retrieve the saved tag by id
  .then((saved) => getConnection().getRepository(Tag).findOne(saved.id))
  .then((tag) => {
    console.log("retrieved tag", {
      id: tag.id,
      serial: Buffer.from(tag.serial, "binary")
        .toString("hex") // convert to hexadecimal string
        .split("")
        .reduce(
          (filled, char) => filled.replace(/x/i, char),
          "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
        ),
    });
  });