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"use strict"
/**
* Emit event if it exists
* @method
*/
function emitSDAMEvent(self, event, description) {
if(self.listeners(event).length > 0) {
self.emit(event, description);
}
}
var getPreviousDescription = function(self) {
if(!self.s.serverDescription) {
self.s.serverDescription = {
address: self.name,
arbiters: [], hosts: [], passives: [], type: 'Unknown'
}
}
return self.s.serverDescription;
}
var emitServerDescriptionChanged = function(self, description) {
if(self.listeners('serverDescriptionChanged').length > 0) {
// Emit the server description changed events
self.emit('serverDescriptionChanged', {
topologyId: self.s.topologyId != -1 ? self.s.topologyId : self.id, address: self.name,
previousDescription: getPreviousDescription(self),
newDescription: description
});
self.s.serverDescription = description;
}
}
var getPreviousTopologyDescription = function(self) {
if(!self.s.topologyDescription) {
self.s.topologyDescription = {
topologyType: 'Unknown',
servers: [{
address: self.name, arbiters: [], hosts: [], passives: [], type: 'Unknown'
}]
}
}
return self.s.topologyDescription;
}
var emitTopologyDescriptionChanged = function(self, description) {
if(self.listeners('topologyDescriptionChanged').length > 0) {
// Emit the server description changed events
self.emit('topologyDescriptionChanged', {
topologyId: self.s.topologyId != -1 ? self.s.topologyId : self.id, address: self.name,
previousDescription: getPreviousTopologyDescription(self),
newDescription: description
});
self.s.serverDescription = description;
}
}
var changedIsMaster = function(self, currentIsmaster, ismaster) {
var currentType = getTopologyType(self, currentIsmaster);
var newType = getTopologyType(self, ismaster);
if(newType != currentType) return true;
return false;
}
var getTopologyType = function(self, ismaster) {
if(!ismaster) {
ismaster = self.ismaster;
}
if(!ismaster) return 'Unknown';
if(ismaster.ismaster && !ismaster.hosts) return 'Standalone';
if(ismaster.ismaster && ismaster.msg == 'isdbgrid') return 'Mongos';
if(ismaster.ismaster) return 'RSPrimary';
if(ismaster.secondary) return 'RSSecondary';
if(ismaster.arbiterOnly) return 'RSArbiter';
return 'Unknown';
}
var inquireServerState = function(self) {
return function(callback) {
if(self.s.state == 'destroyed') return;
// Record response time
var start = new Date().getTime();
// emitSDAMEvent
emitSDAMEvent(self, 'serverHeartbeatStarted', { connectionId: self.name });
// Attempt to execute ismaster command
self.command('admin.$cmd', { ismaster:true }, { monitoring:true }, function(err, r) {
if(!err) {
// Legacy event sender
self.emit('ismaster', r, self);
// Calculate latencyMS
var latencyMS = new Date().getTime() - start;
// Server heart beat event
emitSDAMEvent(self, 'serverHeartbeatSucceeded', { durationMS: latencyMS, reply: r.result, connectionId: self.name });
// Did the server change
if(changedIsMaster(self, self.s.ismaster, r.result)) {
// Emit server description changed if something listening
emitServerDescriptionChanged(self, {
address: self.name, arbiters: [], hosts: [], passives: [], type: !self.s.inTopology ? 'Standalone' : getTopologyType(self)
});
}
// Updat ismaster view
self.s.ismaster = r.result;
// Set server response time
self.s.isMasterLatencyMS = latencyMS;
} else {
emitSDAMEvent(self, 'serverHearbeatFailed', { durationMS: latencyMS, failure: err, connectionId: self.name });
}
// Peforming an ismaster monitoring callback operation
if(typeof callback == 'function') {
return callback(err, r);
}
// Perform another sweep
self.s.inquireServerStateTimeout = setTimeout(inquireServerState(self), self.s.haInterval);
});
};
}
// Object.assign method or polyfille
var assign = Object.assign ? Object.assign : function assign(target, firstSource) {
if (target === undefined || target === null) {
throw new TypeError('Cannot convert first argument to object');
}
var to = Object(target);
for (var i = 1; i < arguments.length; i++) {
var nextSource = arguments[i];
if (nextSource === undefined || nextSource === null) {
continue;
}
var keysArray = Object.keys(Object(nextSource));
for (var nextIndex = 0, len = keysArray.length; nextIndex < len; nextIndex++) {
var nextKey = keysArray[nextIndex];
var desc = Object.getOwnPropertyDescriptor(nextSource, nextKey);
if (desc !== undefined && desc.enumerable) {
to[nextKey] = nextSource[nextKey];
}
}
}
return to;
}
//
// Clone the options
var cloneOptions = function(options) {
var opts = {};
for(var name in options) {
opts[name] = options[name];
}
return opts;
}
module.exports.inquireServerState = inquireServerState
module.exports.getTopologyType = getTopologyType;
module.exports.emitServerDescriptionChanged = emitServerDescriptionChanged;
module.exports.emitTopologyDescriptionChanged = emitTopologyDescriptionChanged;
module.exports.cloneOptions = cloneOptions;
module.exports.assign = assign;
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