Details
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Bug
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Status: Closed (View Workflow)
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Major
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Resolution: Fixed
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None
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None
Description
see https://github.com/MariaDB/mariadb-connector-nodejs/issues/40
The problem is when "piping", to handle the stream when writable stream fails
How to handle writable that stop for any reason ( for example a ClientRequest that has ended):
stream is then in pause mode, waiting for Writable to consume feed. All subsequent request are stopped until stream finished.
I don't see any other solution but to document piping properly to indicate to resume.
Probably a good solution for pool state is that streaming not consumed must be handled when connection is given back to pool.
example :
pool
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.getConnection()
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.then(conn => {
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const someWriterStream = fs.createWriteStream("./tmp.file") |
.on("error", err => { |
//export has ended, resume stream |
queryStream.resume();
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});
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|
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const transform = new Transform({ |
transform: function transformer(chunk, encoding, callback) { |
callback(null, JSON.stringify(chunk)); |
},
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objectMode: true |
});
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|
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const queryStream = conn.queryStream("SELECT seq as val FROM seq_1_to_10000"); |
queryStream
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.pipe(transform)
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.pipe(someWriterStream)
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.on('close', () => { |
conn.end();
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});
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|
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//forcing a WRITER end to simulate this error |
setTimeout(someWriterStream.destroy.bind(someWriterStream), 2);
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})
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.catch(err => { |
//error |
});
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