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node.jspostgresqltypescriptnestjstypeorm

Saving Buffer on Postgres bytea with TypeORM only store 10 bytes

I'm trying to save some images on a postgres db, but only 10 bytes of data are being saved.

The flow is something like this:

I receive a base64 encoded string on my server, then i load that to a Buffer, set it to my entity and save it. But then a try to restore that information from db and i'm getting only 10 bytes of data, verified with octet_length() on a query.

My entity attribute definition:

@Column({ "name": "entima_imagem", "type": "bytea", "nullable": false })
entima_imagem: Buffer;

The code where i receive the data and save it:

entity.entima_imagem = Buffer.from(base64String, "base64");
const repository = this.getRepositoryTarget(Entity);
const saved = await repository.save<any>(entity);

On the server, before saving, i'm writing the file on disc and i can visualize it without problem.

Solution

  • Based on that comment https://github.com/typeorm/typeorm/issues/2878#issuecomment-432725569 and the idea of bytea hex format from there https://www.postgresql.org/docs/9.0/datatype-binary.html I did the following:

    Decoded the Buffer to a hex string, escaped it with \x and then loaded it to a Buffer again.

    entity.entima_imagem = Buffer.from("\\x" + Buffer.from(base64String, "base64").toString("hex"));

    Now the data is saved without problems and i can retrieve them just as it's supposed to be.

    It didn't look so elegant, but solved the problem for now.