CodePattern/15 工程化/2 松耦合/2 消息链/1 只有消息接口.py

################ 待整理 
''' 
应用场景针对各个组件的 notify 方法发指令来驱动所有工作
这是一个示例性质的原型，具体分布式环境下需要调整

notify 用了四种写法，是和本主题无关的测试
'''
from cppy.cp_util import *
from collections import defaultdict

badmsg = lambda : exec ('''  raise Exception("Message not understood " , action ) ''')
class fff:
    def __init__(self, d):
        self._data = defaultdict( badmsg )
        self._data.update(d)

    def __getitem__(self, key):        
        return self._data[key]


class DataStorageMod():    
    def __init__(self):
        self._data = []

    def notify(self, action, *args):
        return {
            'init': lambda : self._init,
            'words': lambda : self._words
        }.get( action , badmsg )()(*args)

    def _init(self, path_to_file):
        self._data = re_split( read_file(path_to_file) )

    def _words(self):
        return self._data
   

class StopWordMod():    
    _stop_words = []

    def notify(self, action, *args):
        return {  'init': self._init,
          'is_stop_word': self._is_stop_word
        }[ action ](*args)  
 
    def _init(self):        
        self._stop_words = get_stopwords()  

    def _is_stop_word(self, wordx):
        return wordx in self._stop_words


class WordFrequencyMod():    
    _word_freqs = {}

    def notify(self, action, *args):        
        return fff( {
            'increment_count':  lambda : self._increment_count,
            'sorted':           lambda : self._sorted
        })[ action ]()(*args)
 
    def _increment_count(self, word):    
        self._word_freqs[word] = self._word_freqs.get(word,0) + 1
        
    def _sorted(self):        
        return sort_dict(self._word_freqs)


class ScenarioManager():

    def notify(self, action, *args):
        if action == 'init':
            return self._init( *args)
        elif action == 'run':
            return self._run()
        else:
            raise Exception("Message not understood " + action )
 
    def _init(self, path_to_file):
        self._storage_manager = DataStorageMod()
        self._stop_word_manager = StopWordMod()
        self._word_freq_manager = WordFrequencyMod()
        self._storage_manager.notify('init', path_to_file)
        self._stop_word_manager.notify('init')

    def _run(self):
        for word  in self._storage_manager.notify('words'):
            if not self._stop_word_manager.notify('is_stop_word', word):
                self._word_freq_manager.notify('increment_count', word )

        word_freqs = self._word_freq_manager.notify('sorted')        
        print_word_freqs(word_freqs)        


if __name__ == '__main__':
    sm = ScenarioManager()
    sm.notify('init', testfilepath)
    sm.notify('run')