Calendar database for resource bookings using leveldb
$ npm install len
You create a len database by passing in an existing leveldb - this can also be a sub-level
var len = require('len');
var level = require('level');
// create a new leveldb - this can also be a sub-level
var leveldb = level('/tmp/lentest');
// create a new lem store using the leveldb
var lendb = len(db);A booking represents a resource being used for a period of time.
Here we create a booking for bob the mechanic:
// start at 9.30
var start = new Date('04/03/14 09:30:00');
// end at 13.30
var end = new Date('04/03/14 13:30:00');
lendb.saveBooking('mechanics.bob', {
id:14,
start:start,
end:end,
meta:{
name:'Fix Car',
customer:34
}
}, function(error, booking){
// bob is all booked in
})We can ask len about bookings for all mechanics in a particular month:
var through = require('through');
var start = new Date('03/01/2014');
var end = new Date('04/01/2014').getTime();
var bookings_in_month = 0;
lendb.createBookingStream('mechanics', {
start:start,
end:end,
// this means booking must start and end inside the window
inclusive:true
}).pipe(through(function(booking){
// booking is an object with 'id', 'start', 'end' and 'meta' keys
bookings_in_month++;
}, function(){
console.log('there are: ' + bookings_in_month.length + ' mechanic bookings in March');
}))Resources are created using paths and this can be a useful way to get booking reports at various layers.
For example - imagine we have a team that does some projects - we want to be able to ask the following questions:
- the start and end point of one project
- an array of bookings for one project
- an array of bookings for all projects
- an array of bookings between certain points for all projects
This can be done using the paths you give to resources - if we create resources with the following paths:
- team.alpha.project.1
- team.alpha.project.2
Then we can ask for the start and end for one project:
lendb.getRange('team.alpha.project.1', function(err, bounds){
// bounds.start = timestamp of the earliest start of booking for the project
// bounds.end = timestamp of the latest end of booking for the project
})get a readstream of bookings:
// bookings for one project
lendb.createBookingStream('team.alpha.project.1').pipe(through(function(booking){
// booking is an object
}))
// bookings for one team's projects
lendb.createBookingStream('team.alpha.project')get a readstream of bookings withing a time period
var start = new Date('03/04/14 09:30:00');
var end = new Date('03/04/14 13:30:00');
lendb.createBookingStream('team.alpha.project', {
start:start,
end:end
})Create a new len database from the provided leveldb. This can be a level-sublevel so you can partition len into an existing database.
var len = require('len');
var level = require('level');
var leveldb = level('/tmp/mylem');
var lendb = len(leveldb);Fetch a booking record using the resourcepath and booking id:
lendb.loadBooking('project.1', 14, function(err, booking){
// booking is an object with 'id', 'start', 'end' and 'meta' keys
})Insert/update a booking into the schedule for a resource.
booking is an object:
{
id: 0, // the id of the booking you are saving - this is auto-created is left blank
start: Date(), // the start timestamp of the booking
end: Date(), // the end timestamp of the booking
meta: { // an object with anything you like for the booking meta-data
customer:12,
comments:'apples'
}
}The start and end timestamps are required - the meta object is converted to a JSON string and is returned in the 'meta' property of bookings.
var start = new Date('03/04/14 09:30:00');
var end = new Date('03/04/14 13:30:00');
lendb.createBooking('project.1', {
id:14,
start:start,
end:end,
meta:{
name:'meta data here'
}
}, function(err){
// the booking is created for the resource
})Remove a booking from the schedule
resource.removeBooking('project.1', 14, function(err){
// the booking is removed
})Use this to get the start and end date for bookings in a resource
lendb.getRange('projects.1', function(err, range){
// range.start and range.end are timestamps
})You can also pass a window to constrain the results:
lendb.getRange('projects.1', {
start:start,
end:end
}, function(err, range){
// range.start and range.end are timestamps
})Use this to get an object stream of bookings for a given resource.
var through = require('through');
lendb.createBookingStream('mechanics.bob', {
start:start,
end:end
}).pipe(through(function(booking){
console.log('booking found');
console.log(booking.id);
}))You can also query the booking stream using a time-window:
var through = require('through');
var start = new Date('03/01/2014');
var end = new Date('04/01/2014').getTime();
var bookings_in_month = 0;
lendb.createBookingStream('mechanics.bob', {
start:start,
end:end,
inclusive:true
}).pipe(through(function(booking){
// booking is an object with 'id', 'start', 'end' and 'meta' keys
bookings_in_month++;
}, function(){
console.log('there are: ' + bookings_in_month.length + ' bookings for bob in March');
}))the inclusive option controls whether bookings have to start and end inside the time window (true) or if any part of it is in the time window (false)
MIT