[IMP] point_of_sale: big reworking of the scale screens:

- no welcome scale in cashier mode, as it was an unnecessary delay for people who use it all day
- no more parallel calls to the proxy which could reorder or make the driver crash
- auto throttling of the proxy calls -> max 20 reads per seconds, but can go slower as well.
- faster and cleaner update of the weight in the scale screen

bzr revid: fva@openerp.com-20130911154155-rs600cixvftvkhoi

addons/point_of_sale/controllers/main.py

@@ -3,12 +3,17 @@ import logging
 import simplejson
 import os
 import openerp
+import time
+import random
 
 from openerp.addons.web import http
 from openerp.addons.web.http import request
 from openerp.addons.web.controllers.main import manifest_list, module_boot, html_template
 
 class PointOfSaleController(http.Controller):
+    def __init__(self):
+        self.scale = 'closed'
+        self.scale_weight = 0.0
 
     @http.route('/pos/app', type='http', auth='admin')
     def app(self):
@@ -64,6 +69,10 @@ class PointOfSaleController(http.Controller):
 
         return m
 
+    @http.route('/pos/test_connection', type='json', auth='admin')
+    def test_connection(self):
+        return
+
     @http.route('/pos/scan_item_success', type='json', auth='admin')
     def scan_item_success(self, ean):
         """
@@ -98,18 +107,38 @@ class PointOfSaleController(http.Controller):
 
     @http.route('/pos/weighting_start', type='json', auth='admin')
     def weighting_start(self):
-        print "weighting_start"
+        if self.scale == 'closed':
+            print "Opening (Fake) Connection to Scale..."
+            self.scale = 'open'
+            self.scale_weight = 0.0
+            time.sleep(0.1)
+            print "... Scale Open."
+        else:
+            print "WARNING: Scale already Connected !!!"
         return 
 
     @http.route('/pos/weighting_read_kg', type='json', auth='admin')
     def weighting_read_kg(self):
-        print "weighting_read_kg"
+        if self.scale == 'open':
-        return 3.14
+            print "Reading Scale..."
+            time.sleep(0.025)
+            self.scale_weight += 0.01
+            print "... Done."
+            return self.scale_weight
+        else:
+            print "WARNING: Reading closed scale !!!"
+            return 0.0
 
     @http.route('/pos/weighting_end', type='json', auth='admin')
     def weighting_end(self):
-        print "weighting_end"
+        if self.scale == 'open':
-        return 
+            print "Closing Connection to Scale ..."
+            self.scale = 'closed'
+            self.scale_weight = 0.0
+            time.sleep(0.1)
+            print "... Scale Closed."
+        else:
+            print "WARNING: Scale already Closed !!!"
 
     @http.route('/pos/payment_request', type='json', auth='admin')
     def payment_request(self, price):

addons/point_of_sale/static/src/js/devices.js

@@ -1,6 +1,81 @@
 
 function openerp_pos_devices(instance,module){ //module is instance.point_of_sale
 
+    // the JobQueue schedules a sequence of 'jobs'. each job is
+    // a function returning a deferred. the queue waits for each job to finish 
+    // before launching the next. Each job can also be scheduled with a delay. 
+    // the  is used to prevent parallel requests to the proxy.
+
+    module.JobQueue = function(){
+        var queue = [];
+        var running = false;
+        var scheduled_end_time = 0;
+        var end_of_queue = (new $.Deferred()).resolve();
+        var stoprepeat = false;
+
+        var run = function(){
+            if(end_of_queue.state() === 'resolved'){
+                end_of_queue =  new $.Deferred();
+            }
+            if(queue.length > 0){
+                running = true;
+                var job = queue[0];
+                if(!job.opts.repeat || stoprepeat){
+                    queue.shift();
+                    stoprepeat = false;
+                }
+
+                // the time scheduled for this job
+                scheduled_end_time = (new Date()).getTime() + (job.opts.duration || 0);
+
+                // we run the job and put in def when it finishes
+                var def = job.fun() || (new $.Deferred()).resolve();
+                
+                // we don't care if a job fails ... 
+                def.always(function(){
+                    // we run the next job after the scheduled_end_time, even if it finishes before
+                    setTimeout(function(){
+                        run();
+                    }, Math.max(0, scheduled_end_time - (new Date()).getTime()) ); 
+                });
+            }else{
+                running = false;
+                end_of_queue.resolve();
+            }
+        };
+        
+        // adds a job to the schedule.
+        // opts : {
+        //    duration    : the job is guaranteed to finish no quicker than this (milisec)
+        //    repeat      : if true, the job will be endlessly repeated
+        //    important   : if true, the scheduled job cannot be canceled by a queue.clear()
+        // }
+        this.schedule  = function(fun, opts){
+            queue.push({fun:fun, opts:opts || {}});
+            if(!running){
+                run();
+            }
+        }
+
+        // remove all jobs from the schedule (except the ones marked as important)
+        this.clear = function(){
+            queue = _.filter(queue,function(job){job.opts.important === true}); 
+        };
+
+        // end the repetition of the current job
+        this.stoprepeat = function(){
+            stoprepeat = true;
+        };
+        
+        // returns a deferred that resolves when all scheduled 
+        // jobs have been run.
+        // ( jobs added after the call to this method are considered as well )
+        this.finished = function(){
+            return end_of_queue;
+        }
+
+    };
+
     // this object interfaces with the local proxy to communicate to the various hardware devices
     // connected to the Point of Sale. As the communication only goes from the POS to the proxy,
     // methods are used both to signal an event, and to fetch information. 
@@ -10,7 +85,6 @@ function openerp_pos_devices(instance,module){ //module is instance.point_of_sal
             options = options || {};
             url = options.url || 'http://localhost:8069';
             
-            this.weight = 0;
             this.weighting = false;
             this.debug_weight = 0;
             this.use_debug_weight = false;
@@ -35,18 +109,11 @@ function openerp_pos_devices(instance,module){ //module is instance.point_of_sal
             this.connection.destroy();
         },
         message : function(name,params){
-            var ret = new $.Deferred();
             var callbacks = this.notifications[name] || [];
             for(var i = 0; i < callbacks.length; i++){
                 callbacks[i](params);
             }
-
+            return this.connection.rpc('/pos/' + name, params || {});       
-            this.connection.rpc('/pos/' + name, params || {}).done(function(result) {
-                ret.resolve(result);
-            }).fail(function(error) {
-                ret.reject(error);
-            });
-            return ret;
         },
 
         // this allows the client to be notified when a proxy call is made. The notification 
@@ -82,14 +149,32 @@ function openerp_pos_devices(instance,module){ //module is instance.point_of_sal
 
         //the client is starting to weight
         weighting_start: function(){
+            var ret = new $.Deferred();
             if(!this.weighting){
                 this.weighting = true;
-                this.weight = 0;
+                this.message('weighting_start').always(function(){
-                return this.message('weighting_start');
+                    ret.resolve();
+                });
             }else{
                 console.error('Weighting already started!!!');
-                this.weight = 0;
+                ret.resolve();
             }
+            return ret;
+        },
+
+        // the client has finished weighting products
+        weighting_end: function(){
+            var ret = new $.Deferred();
+            if(this.weighting){
+                this.weighting = false;
+                this.message('weighting_end').always(function(){
+                    ret.resolve();
+                });
+            }else{
+                console.error('Weighting already ended !!!');
+                ret.resolve();
+            }
+            return ret;
         },
 
         //returns the weight on the scale. 
@@ -97,20 +182,14 @@ function openerp_pos_devices(instance,module){ //module is instance.point_of_sal
         // and a weighting_end()
         weighting_read_kg: function(){
             var self = this;
-            if(!this.weighting){
+            var ret = new $.Deferred();
-                console.error('Weighting while not started!!!');
-            }
             this.message('weighting_read_kg',{})
-                .done(function(weight){
+                .then(function(weight){
-                    if(self.weighting){
+                    ret.resolve(self.use_debug_weight ? self.debug_weight : weight);
-                        if(self.use_debug_weight){
+                }, function(){ //failed to read weight
-                            self.weight = self.debug_weight;
+                    ret.resolve(self.use_debug_weight ? self.debug_weight : 0.0);
-                        }else{
-                            self.weight = weight;
-                        }
-                    }
                 });
-            return this.weight;
+            return ret;
         },
 
         // sets a custom weight, ignoring the proxy returned value. 
@@ -125,17 +204,6 @@ function openerp_pos_devices(instance,module){ //module is instance.point_of_sal
             this.debug_weight = 0;
         },
 
-        // the client has finished weighting products
-        weighting_end: function(){
-            if(this.weighting){
-                this.weight = 0;
-                this.weighting = false;
-                this.message('weighting_end');
-            }else{
-                console.error('Weighting already ended !!!');
-                this.weight = 0;
-            }
-        },
 
         // the pos asks the client to pay 'price' units
         payment_request: function(price){

addons/point_of_sale/static/src/js/models.js

@@ -24,6 +24,7 @@ function openerp_pos_models(instance, module){ //module is instance.point_of_sal
 
             this.barcode_reader = new module.BarcodeReader({'pos': this});  // used to read barcodes
             this.proxy = new module.ProxyDevice();              // used to communicate to the hardware devices via a local proxy
+            this.proxy_queue = new module.JobQueue();         // used to prevent parallels communications to the proxy
             this.db = new module.PosLS();                       // a database used to store the products and categories
             this.db.clear('products','categories');
             this.debug = jQuery.deparam(jQuery.param.querystring()).debug !== undefined;    //debug mode 

addons/point_of_sale/static/src/js/screens.js

@@ -441,7 +441,7 @@ function openerp_pos_screens(instance, module){ //module is instance.point_of_sa
     module.ErrorInvoiceTransferPopupWidget = module.ErrorPopupWidget.extend({
         template: 'ErrorInvoiceTransferPopupWidget',
     });
-
+                
     module.ScaleInviteScreenWidget = module.ScreenWidget.extend({
         template:'ScaleInviteScreenWidget',
 
@@ -451,30 +451,35 @@ function openerp_pos_screens(instance, module){ //module is instance.point_of_sa
         show: function(){
             this._super();
             var self = this;
+            var queue = this.pos.proxy_queue;
 
-            self.pos.proxy.weighting_start();
+            queue.schedule(function(){
-
+                return self.pos.proxy.weighting_start();
-            this.intervalID = setInterval(function(){
+            },{ unclearable: true });
-                var weight = self.pos.proxy.weighting_read_kg();
+            
-                if(weight > 0.001){
+            queue.schedule(function(){
-                    clearInterval(this.intervalID);
+                return self.pos.proxy.weighting_read_kg().then(function(weight){
-                    self.pos_widget.screen_selector.set_current_screen(self.next_screen);
+                    if(weight > 0.001){
-                }
+                        self.pos_widget.screen_selector.set_current_screen(self.next_screen);
-            },50);
+                    }
+                });
+            },{duration: 100, repeat: true});
 
             this.add_action_button({
                     label: _t('Back'),
                     icon: '/point_of_sale/static/src/img/icons/png48/go-previous.png',
                     click: function(){  
-                        clearInterval(this.intervalID);
                         self.pos_widget.screen_selector.set_current_screen(self.previous_screen);
                     }
                 });
         },
         close: function(){
             this._super();
-            clearInterval(this.intervalID);
+            var self = this;
-            this.pos.proxy.weighting_end();
+            this.pos.proxy_queue.clear();
+            this.pos.proxy_queue.schedule(function(){
+                return self.pos.proxy.weighting_end();
+            },{ unclearable: true });
         },
     });
 
@@ -486,9 +491,11 @@ function openerp_pos_screens(instance, module){ //module is instance.point_of_sa
 
         show: function(){
             this._super();
-            this.renderElement();
             var self = this;
+            var queue = this.pos.proxy_queue;
 
+            this.set_weight(0);
+            this.renderElement();
 
             this.add_action_button({
                     label: _t('Back'),
@@ -507,14 +514,16 @@ function openerp_pos_screens(instance, module){ //module is instance.point_of_sa
                     },
                 });
             
-            this.pos.proxy.weighting_start();
+            queue.schedule(function(){
-            this.intervalID = setInterval(function(){
+                return self.pos.proxy.weighting_start()
-                var weight = self.pos.proxy.weighting_read_kg();
+            },{ unclearable: true });
-                if(weight != self.weight){
+            
-                    self.weight = weight;
+            queue.schedule(function(){
-                    self.$('.js-weight').text(self.get_product_weight_string());
+                return self.pos.proxy.weighting_read_kg().then(function(weight){
-                }
+                    self.set_weight(weight);
-            },50);
+                });
+            },{duration:50, repeat: true});
+
         },
         renderElement: function(){
             var self = this;
@@ -544,54 +553,24 @@ function openerp_pos_screens(instance, module){ //module is instance.point_of_sa
             var product = this.get_product();
             return (product ? product.get('price') : 0) || 0;
         },
+        set_weight: function(weight){
+            this.weight = weight;
+            this.$('.js-weight').text(this.get_product_weight_string());
+        },
         get_product_weight_string: function(){
             return (this.weight || 0).toFixed(3) + ' Kg';
         },
         close: function(){
+            var self = this;
             this._super();
-            clearInterval(this.intervalID);
+
-            this.pos.proxy.weighting_end();
+            this.pos.proxy_queue.clear();
+            this.pos.proxy_queue.schedule(function(){
+                self.pos.proxy.weighting_end();
+            },{ unclearable: true });
         },
     });
 
-    // the JobQueue schedules a sequence of 'jobs'. each job is
-    // a function returning a deferred. the queue waits for each job to finish 
-    // before launching the next. Each job can also be scheduled with a delay. 
-    // the queue jobqueue is used to prevent parallel requests to the payment terminal.
-
-    module.JobQueue = function(){
-        var queue = [];
-        var running = false;
-        var run = function(){
-            if(queue.length > 0){
-                running = true;
-                var job = queue.shift();
-                setTimeout(function(){
-                    var def = job.fun();
-                    if(def){
-                        def.done(run);
-                    }else{
-                        run();
-                    }
-                },job.delay || 0);
-            }else{
-                running = false;
-            }
-        };
-        
-        // adds a job to the schedule.
-        this.schedule  = function(fun, delay){
-            queue.push({fun:fun, delay:delay});
-            if(!running){
-                run();
-            }
-        }
-
-        // remove all jobs from the schedule
-        this.clear = function(){
-            queue = [];
-        };
-    };
 
     module.ClientPaymentScreenWidget =  module.ScreenWidget.extend({
         template:'ClientPaymentScreenWidget',