Re: Postgres driver bug

So it appears that this is a bit of a corner case. The copy is not active

Sure send a PR please

Dave Cramer

dave.cramer(at)credativ(dot)ca
http://www.credativ.ca

On 6 February 2015 at 09:31, Nikos Viorres <nviorres(at)gmail(dot)com> wrote:

> Well, the driver shouldn't be waiting for input since the InpuStream has
> been closed, this is a try with resources. I think that the lock should be
> released as soon as the IS is closed.
>
> regards
>
> On Fri, Feb 6, 2015 at 4:27 PM, Dave Cramer <pg(at)fastcrypt(dot)com> wrote:
>
>> IIRC this is due to the driver waiting for input from the client ?
>>
>> What would you suggest it do ?
>>
>> Dave Cramer
>>
>> dave.cramer(at)credativ(dot)ca
>> http://www.credativ.ca
>>
>> On 6 February 2015 at 09:19, Nikos Viorres <nviorres(at)gmail(dot)com> wrote:
>>
>>> Hi Dave,
>>>
>>> I am using 9.3-1102-jdbc4 version of the driver. You are correct, getOutputStream()
>>> will always throw an exception after getInputStream has been called so as
>>> to avoid reading the bytes from the IS and releasing the internal lock that
>>> the driver keeps and thus always resulting in an infinite wait.
>>>
>>> regards
>>>
>>> On Fri, Feb 6, 2015 at 3:23 PM, Dave Cramer <pg(at)fastcrypt(dot)com> wrote:
>>>
>>>> Nikos,
>>>>
>>>> What version of the driver are you using ?
>>>>
>>>> From what I see getOutputStream() will always throw an exception ?
>>>>
>>>> Dave
>>>>
>>>> Dave Cramer
>>>>
>>>> dave.cramer(at)credativ(dot)ca
>>>> http://www.credativ.ca
>>>>
>>>> On 6 February 2015 at 03:57, Nikos Viorres <nviorres(at)gmail(dot)com> wrote:
>>>>
>>>>> Hi,
>>>>>
>>>>> The attached simple piece of code results always in a the driver going
>>>>> into a wait state that never receives a wake up signal and by looking at
>>>>> the code, even if it does it will loop again into the same wait state. If
>>>>> anyone else thinks this is a problem i could provide a fix
>>>>>
>>>>> regards
>>>>>
>>>>>
>>>>>
>>>>> package nvrs.test;
>>>>>
>>>>> import org.postgresql.PGConnection;
>>>>> import org.postgresql.copy.PGCopyInputStream;
>>>>>
>>>>> import java.io.FileNotFoundException;
>>>>> import java.io.IOException;
>>>>> import java.io.InputStream;
>>>>> import java.io.OutputStream;
>>>>> import java.sql.Connection;
>>>>> import java.sql.DriverManager;
>>>>> import java.sql.SQLException;
>>>>>
>>>>> /**
>>>>> * Date: 5/2/2015
>>>>> */
>>>>> public class PostgresDriverBug {
>>>>>
>>>>> public static void main(String...args) throws SQLException {
>>>>> PostgresConnectionFactory connectionFactory
>>>>> = new PostgresConnectionFactory("localhost", 5432, "postgres",
>>>>> "postgres", "postgres");
>>>>>
>>>>> Connection con = connectionFactory.getNewConnection();
>>>>>
>>>>>
>>>>> try (InputStream is = getPostgresInputStream("select * from
>>>>> public.some_table", con);
>>>>> OutputStream os = getOutputStream()) {
>>>>>
>>>>> final byte[] buffer = new byte[1024 * 4];
>>>>> int read = is.read(buffer);
>>>>>
>>>>> while (read > 0) {
>>>>> os.write(buffer, 0, read);
>>>>> read = is.read(buffer);
>>>>> }
>>>>>
>>>>> } catch (IOException e) {
>>>>> System.err.println("Something bad happened " + e.getMessage());
>>>>>
>>>>> con.rollback();
>>>>> }
>>>>>
>>>>> System.out.println("Done!");
>>>>> }
>>>>>
>>>>> private static OutputStream getOutputStream() throws IOException {
>>>>> throw new FileNotFoundException("ooops");
>>>>> }
>>>>>
>>>>> private static InputStream getPostgresInputStream(String
>>>>> selectQuery, Connection con)
>>>>> throws SQLException {
>>>>>
>>>>> return new PGCopyInputStream(PGConnection.class.cast(con),
>>>>> "COPY (" + selectQuery +") TO
>>>>> STDOUT");
>>>>> }
>>>>>
>>>>> public static class PostgresConnectionFactory {
>>>>> private final String host;
>>>>> private final int port;
>>>>> private final String database;
>>>>> private final String user;
>>>>> private final String password;
>>>>>
>>>>> public PostgresConnectionFactory(final String host, final int
>>>>> port, final String database,
>>>>> final String user, final String
>>>>> password) {
>>>>> this.host = host;
>>>>> this.port = port;
>>>>> this.database = database;
>>>>> this.user = user;
>>>>> this.password = password;
>>>>> }
>>>>>
>>>>> private String getConnectionUrl() {
>>>>> return "jdbc:postgresql://" + host + ":" + port + "/" + database;
>>>>> }
>>>>>
>>>>> public Connection getNewConnection() throws SQLException {
>>>>> Connection con = DriverManager.getConnection(getConnectionUrl(),
>>>>> user,
>>>>> password);
>>>>>
>>>>> con.setAutoCommit(false);
>>>>> return con;
>>>>> }
>>>>> }
>>>>>
>>>>> }
>>>>>
>>>>
>>>>
>>>
>>
>