/
viewBuilderBase.js
135 lines (108 loc) · 2.94 KB
/
viewBuilderBase.js
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
var _ = require('lodash'),
eventEmitter = require('../eventEmitter');
function dive(obj, key) {
var keys = key.split('.');
var x = 0;
var value = obj;
while (keys[x]) {
value = value && value[keys[x]];
x++;
}
return value;
}
var ViewBuilder = {};
ViewBuilder.prototype = {
configure: function(fn) {
fn.call(this);
return this;
},
use: function(module) {
if (!module) return;
if (module.commit) {
this.repository = module;
}
},
loadViewModel: function(id, callback) {
this.repository.get(id, callback);
},
saveViewModel: function(vm, callback) {
this.repository.commit(vm, callback);
},
setOptions: function(options) {
this.options = options;
},
'create': function(evt, vm) {
this.defaultAction(evt, vm, 'create');
},
'update': function(evt, vm) {
this.defaultAction(evt, vm, 'update');
},
'delete': function(evt, vm) {
this.defaultAction(evt, vm, 'delete');
},
defaultAction: function(evt, vm, action) {
if(action !== 'delete') {
_.extend(vm, evt.payload);
} else {
vm.destroy();
}
},
handle: function(evt) {
var self = this;
// Map events to function names:
// - For the event handler matching the current event, its name is returned
// - For all other event handlers, undefined is returned
var fnNames = _.map(this.events, function(item) {
if (_.isString(item) && item === evt.event) {
return item;
} else if (item[evt.event]) {
return item[evt.event];
}
}
);
// Reduce function names to function name:
// - Replace all undefineds by an empty string
// - Keep all non-undefined values
//
// NOTE: This will fail if multiple event handlers match the current event,
// but this is not allowed anyway, so it can only happen on error.
var fnName = _.reduce(fnNames, function(memo, item) {
return memo + (item || '');
}, '');
if(this[fnName]) {
var vmIdPath = 'payload.id';
if (this.viewModelIds && this.viewModelIds[evt.event]) {
vmIdPath = this.viewModelIds[evt.event];
}
var vmId = dive(evt, vmIdPath);
this.loadViewModel(vmId, function(err, vm) {
if (err) {
throw err;
}
// Call the event handler found by map-reduce.
self[fnName](evt, vm);
self.saveViewModel(vm, function(err) {
if (err && err.name === 'ConcurrencyError') {
setTimeout(function() {
self.handle(evt);
}, 100);
return;
}
if (err) {
throw err;
}
eventEmitter.emit('denormalized:' + evt.event, evt);
});
});
} else {
throw new Error('missing handle function');
}
}
};
module.exports = {
extend: function(obj) {
var newObj = _.extend(_.clone(ViewBuilder.prototype), obj);
newObj.options = {};
return newObj;
}
};