Hi Sverre,
in my apps (Spring Boot + Vaadin + JOOQ) I also have to store files
uploaded by the user.
If I do this in the Postgresql, which is BTW not everytime a good solution,
I usually split document meta data (filename, MIME type, size etc.) from
document content (the byte array only).
Often, the UI shows some document meta data in the first place and storing
and retrieving has to be therefore pretty easy,.
And my method for storing the maybe large content looks like this, and
surprisingly the comment contains a link to this group WHY it look so :-)
/**
* @see https://groups.google.com/g/jooq-user/c/Gwn0rce_J-Q Daher wird
das hier
*/
private void storeContent(Integer id, byte[] content) {
if (this.jooq.configuration().connectionProvider() instanceof
DataSourceConnectionProvider dscp) {
var dataSource = dscp.dataSource();
try (Connection conn = dataSource.getConnection();
ByteArrayInputStream is = new
ByteArrayInputStream(content);
PreparedStatement ps = conn.prepareStatement("insert into
document_storage (id, content) values (?, ?)")) {
ps.setInt(1, id);
ps.setBinaryStream(2, is, content.length);
ps.executeUpdate();
} catch (Exception ex) {
log.error(ex.getMessage());
}
}
}
Hope that helps
Kind regards
Dominik
On Wednesday, 29 November 2023 at 18:30:18 UTC+1 sverre.ale...@gmail.com
wrote:
> Hi,
>
> I have a use case where I store and retrieve large blobs (1 MB - 200 MB)
> from a postgres database.
>
> On the input side I've managed to stream spring boot MultipartFiles from a
> REST interface all the way into the DB using the following code:
> public class StreamingBlobBinding implements Binding<byte[], InputStream>
> {
> @Override
> public Converter<byte[], InputStream> converter() {
> return new Converter<>() {
>
> @Override
> public InputStream from(byte[] bytes) {
> return new ByteArrayInputStream(bytes);
> }
>
> @Override
> public byte[] to(InputStream inputStream) {
> try {
> return IOUtils.toByteArray(inputStream);
> } catch (IOException e) {
> throw new RuntimeException(e);
> }
> }
>
> @Override
> public Class<byte[]> fromType() {
> return byte[].class;
> }
>
> @Override
> public Class<InputStream> toType() {
> return InputStream.class;
> }
> };
> }
>
> @Override
> public void sql(BindingSQLContext<InputStream> ctx) {
> if (ctx.render().paramType() == ParamType.INLINED) {
> ctx.render().visit(DSL.inline(ctx.convert(converter()).value()));
> } else {
> ctx.render().sql(ctx.variable());
> }
> }
>
> @Override
> public void register(BindingRegisterContext<InputStream> ctx) throws
> SQLException
> {
> ctx.statement().registerOutParameter(ctx.index(), Types.BLOB);
> }
>
> @Override
> public void set(BindingSetStatementContext<InputStream> ctx) throws
> SQLException
> {
> // This line is responsible for the streaming
> ctx.statement().setBinaryStream(ctx.index(), ctx.value());
> }
>
> @Override
> public void set(BindingSetSQLOutputContext<InputStream>
> bindingSetSQLOutputContext) throws SQLException {
> throw new SQLFeatureNotSupportedException();
> }
>
> @Override
> public void get(BindingGetResultSetContext<InputStream>
> bindingGetResultSetContext) throws SQLException {
> throw new SQLFeatureNotSupportedException();
> }
>
> @Override
> public void get(BindingGetStatementContext<InputStream>
> bindingGetStatementContext) throws SQLException {
> throw new SQLFeatureNotSupportedException();
> }
>
> @Override
> public void get(BindingGetSQLInputContext<InputStream>
> bindingGetSQLInputContext) throws SQLException {
> throw new SQLFeatureNotSupportedException();
> }
> }
>
> and
>
> public static long saveFileData(MultipartFile file) throws IOException {
> final var id = uow.ctx.nextval(FILE_DATA_SEQ);
> var inputStreamType = FILE_DATA.DATA.getDataType().asConvertedDataType(new
> StreamingBlobBinding());
> var dataColumn = DSL.field(FILE_DATA.DATA.getName(), inputStreamType);
> var result = uow.ctx.insertInto(FILE_DATA)
> .columns(FILE_DATA.ID, dataColumn)
> .values(DSL.val(id, FILE_DATA.ID.getDataType()),
> DSL.val(file.getInputStream(), inputStreamType))
> .execute();
>
> if (result != 1) {
> throw new DataAccessException("Unable to store filedata");
> }
>
> return id;
> }
>
>
> I'm having more difficulty getting it to work the other way around, i.e.
> having Jooq fetch a BLOB from postgres and storing the result using a
> OutputStream. Do anyone have any tips on how I can achieve this?
>
> Best regards,
> Sverre Aleksandersen
>
--
You received this message because you are subscribed to the Google Groups "jOOQ
User Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to jooq-user+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/jooq-user/6a8de7e2-bd55-4033-86fd-0c9bc943a592n%40googlegroups.com.
