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@numtel
Last active Jan 21, 2020
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What would you like to do?
Restart ZongJi gracefully on error
var ZongJi = require('zongji');
var RETRY_TIMEOUT = 4000;
function zongjiManager(dsn, options, onBinlog) {
var newInst = new ZongJi(dsn, options);
newInst.on('error', function(reason) {
newInst.removeListener('binlog', onBinlog);
setTimeout(function() {
// If multiple errors happened, a new instance may have already been created
if(!('child' in newInst)) {
newInst.child = zongjiManager(dsn, Object.assign({}, options, {
binlogName: newInst.binlogName,
binlogNextPos: newInst.binlogNextPos
}), onBinlog);
newInst.emit('child', newInst.child, reason);
newInst.child.on('child', child => newInst.emit('child', child));
}
}, RETRY_TIMEOUT);
});
newInst.on('binlog', onBinlog);
newInst.start(options);
return newInst;
}
// To check if it works
var eventCount = 0;
setInterval(function() { console.log('Events:', eventCount) }, 2000);
var zongji = zongjiManager(
// Pass the connection settings
{
host : 'localhost',
user : 'root',
password : 'numtel',
},
// Pass the options
// Must include rotate events for binlogName and binlogNextPos properties
{
includeEvents: ['rotate', 'tablemap', 'writerows', 'updaterows', 'deleterows'],
},
// Binlog callback that will be attached each time Zongji is restarted
function(event) {
eventCount++
event.dump();
});
var newest = zongji;
zongji.on('child', function(child, reason) {
console.log('New Instance Created', reason);
newest.stop();
newest = child;
});
process.on('SIGINT', function() {
console.log('Got SIGINT.');
newest.stop();
process.exit();
});
@YousefED

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@YousefED YousefED commented May 3, 2019

@numtel this will create a new Zongji instance, but the new instance doesn't have the TableMap yet right?

This would mean that events might be filtered out, until we get a new tablemap? Are my assumptions correct? What approach would you recommend here?

@stephen-dahl

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@stephen-dahl stephen-dahl commented Jan 21, 2020

correct variables to access binlog filename/position are

newInst.options.filename,
newInst.options.position
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