1 """ |
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2 Handles mapping URLs to request handlers |
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3 """ |
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4 |
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5 from qmsk.web import http, handler |
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6 |
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7 class MapperError (http.ResponseError) : |
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8 """ |
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9 URL could not be mapped |
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10 """ |
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11 |
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12 def __init__ (self, url) : |
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13 super(MapperError, self).__init__("URL not found: %s" % (url, ), status='404 Not Found') |
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14 |
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15 class Mapper (handler.RequestHandler) : |
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16 """ |
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17 Looks up the handler to use based on the URL |
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18 """ |
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19 |
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20 def handle_request (self, request) : |
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21 """ |
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22 Map the given request |
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23 """ |
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24 |
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25 abstract |
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26 |
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27 class Mapping (object) : |
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28 """ |
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29 A mapping object for StaticMapping |
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30 """ |
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31 |
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32 def test (self, request) : |
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33 """ |
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34 Either return a handler, or None |
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35 """ |
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36 |
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37 abstract |
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38 |
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39 class RegexpMapping (object) : |
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40 """ |
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41 A mapping object that uses regular expressions |
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42 """ |
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43 |
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44 def __init__ (self, regexp, handler) : |
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45 pass |
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46 |
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47 def test (self, request) : |
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48 xxx |
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49 |
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50 class SimpleMapping (object) : |
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51 """ |
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52 A mapping object that uses simple expressions |
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53 """ |
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54 |
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55 def __init__ (self, expression, handler) : |
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56 pass |
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57 |
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58 def test (self, request) : |
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59 xxx |
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60 |
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61 class StaticMapper (Mapper) : |
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62 """ |
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63 Translates requests to handlers using a list of pre-determined Mapping's |
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64 """ |
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65 |
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66 def __init__ (self, mappings) : |
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67 # store |
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68 self.mappings = mappings |
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69 |
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70 def handle_request (self, request) : |
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71 """ |
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72 Returns the appropriate handler |
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73 """ |
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74 |
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75 # find handler to use |
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76 handler = None |
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77 |
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78 # just test each mapping in turn |
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79 for mapping in self.mappings : |
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80 handler = mapping.test(request) |
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81 |
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82 if handler : |
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83 break |
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84 |
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85 if not handler : |
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86 # fail, not found |
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87 raise MapperError(request.get_page_name()) |
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88 |
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89 # passthrough |
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90 return handler.handle_request(request) |
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91 |
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92 # "friendly" names |
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93 map = SimpleMapping |
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94 mapre = RegexpMapping |
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95 |
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