Coverage for /pythoncovmergedfiles/medio/medio/usr/local/lib/python3.8/site-packages/nbconvert/exporters/slides.py: 32%

1"""HTML slide show Exporter class""" 

2 

3# Copyright (c) Jupyter Development Team. 

4# Distributed under the terms of the Modified BSD License. 

5 

6from copy import deepcopy 

7from warnings import warn 

8 

9from traitlets import Bool, Unicode, default 

10 

11from nbconvert.preprocessors.base import Preprocessor 

12 

13from .html import HTMLExporter 

14 

15 

16class _RevealMetadataPreprocessor(Preprocessor): 

17 # A custom preprocessor adding convenience metadata to cells 

18 

19 def preprocess(self, nb, resources=None): 

20 nb = deepcopy(nb) 

21 

22 for cell in nb.cells: 

23 # Make sure every cell has a slide_type 

24 try: 

25 slide_type = cell.metadata.get("slideshow", {}).get("slide_type", "-") 

26 except AttributeError: 

27 slide_type = "-" 

28 cell.metadata.slide_type = slide_type 

29 

30 # Find the first visible cell 

31 for index, cell in enumerate(nb.cells): 

32 if cell.metadata.slide_type not in {"notes", "skip"}: 

33 cell.metadata.slide_type = "slide" 

34 cell.metadata.slide_start = True 

35 cell.metadata.subslide_start = True 

36 first_slide_ix = index 

37 break 

38 else: 

39 msg = "All cells are hidden, cannot create slideshow" 

40 raise ValueError(msg) 

41 

42 in_fragment = False 

43 

44 for index, cell in enumerate(nb.cells[first_slide_ix + 1 :], start=(first_slide_ix + 1)): 

45 previous_cell = nb.cells[index - 1] 

46 

47 # Slides are <section> elements in the HTML, subslides (the vertically 

48 # stacked slides) are also <section> elements inside the slides, 

49 # and fragments are <div>s within subslides. Subslide and fragment 

50 # elements can contain content: 

51 # <section> 

52 # <section> 

53 # (content) 

54 # <div class="fragment">(content)</div> 

55 # </section> 

56 # </section> 

57 

58 # Get the slide type. If type is subslide or slide, 

59 # end the last slide/subslide/fragment as applicable. 

60 if cell.metadata.slide_type == "slide": 

61 previous_cell.metadata.slide_end = True 

62 cell.metadata.slide_start = True 

63 if cell.metadata.slide_type in {"subslide", "slide"}: 

64 previous_cell.metadata.fragment_end = in_fragment 

65 previous_cell.metadata.subslide_end = True 

66 cell.metadata.subslide_start = True 

67 in_fragment = False 

68 

69 elif cell.metadata.slide_type == "fragment": 

70 cell.metadata.fragment_start = True 

71 if in_fragment: 

72 previous_cell.metadata.fragment_end = True 

73 else: 

74 in_fragment = True 

75 

76 # The last cell will always be the end of a slide 

77 nb.cells[-1].metadata.fragment_end = in_fragment 

78 nb.cells[-1].metadata.subslide_end = True 

79 nb.cells[-1].metadata.slide_end = True 

80 

81 return nb, resources 

82 

83 

84class SlidesExporter(HTMLExporter): 

85 """Exports HTML slides with reveal.js""" 

86 

87 # Overrides from HTMLExporter 

88 ################################# 

89 export_from_notebook = "Reveal.js slides" 

90 

91 @default("template_name") 

92 def _template_name_default(self): 

93 return "reveal" 

94 

95 @default("file_extension") 

96 def _file_extension_default(self): 

97 return ".slides.html" 

98 

99 @default("template_extension") 

100 def _template_extension_default(self): 

101 return ".html.j2" 

102 

103 # Extra resources 

104 ################################# 

105 reveal_url_prefix = Unicode( 

106 help="""The URL prefix for reveal.js (version 3.x). 

107 This defaults to the reveal CDN, but can be any url pointing to a copy 

108 of reveal.js. 

109 

110 For speaker notes to work, this must be a relative path to a local 

111 copy of reveal.js: e.g., "reveal.js". 

112 

113 If a relative path is given, it must be a subdirectory of the 

114 current directory (from which the server is run). 

115 

116 See the usage documentation 

117 (https://nbconvert.readthedocs.io/en/latest/usage.html#reveal-js-html-slideshow) 

118 for more details. 

119 """ 

120 ).tag(config=True) 

121 

122 @default("reveal_url_prefix") 

123 def _reveal_url_prefix_default(self): 

124 if "RevealHelpPreprocessor.url_prefix" in self.config: 

125 warn( 

126 "Please update RevealHelpPreprocessor.url_prefix to " 

127 "SlidesExporter.reveal_url_prefix in config files.", 

128 stacklevel=2, 

129 ) 

130 return self.config.RevealHelpPreprocessor.url_prefix 

131 return "https://unpkg.com/reveal.js@4.0.2" 

132 

133 reveal_theme = Unicode( 

134 "simple", 

135 help=""" 

136 Name of the reveal.js theme to use. 

137 

138 We look for a file with this name under 

139 ``reveal_url_prefix``/css/theme/``reveal_theme``.css. 

140 

141 https://github.com/hakimel/reveal.js/tree/master/css/theme has 

142 list of themes that ship by default with reveal.js. 

143 """, 

144 ).tag(config=True) 

145 

146 reveal_transition = Unicode( 

147 "slide", 

148 help=""" 

149 Name of the reveal.js transition to use. 

150 

151 The list of transitions that ships by default with reveal.js are: 

152 none, fade, slide, convex, concave and zoom. 

153 """, 

154 ).tag(config=True) 

155 

156 reveal_scroll = Bool( 

157 False, 

158 help=""" 

159 If True, enable scrolling within each slide 

160 """, 

161 ).tag(config=True) 

162 

163 reveal_number = Unicode( 

164 "", 

165 help=""" 

166 slide number format (e.g. 'c/t'). Choose from: 

167 'c': current, 't': total, 'h': horizontal, 'v': vertical 

168 """, 

169 ).tag(config=True) 

170 

171 font_awesome_url = Unicode( 

172 "https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.css", 

173 help=""" 

174 URL to load font awesome from. 

175 

176 Defaults to loading from cdnjs. 

177 """, 

178 ).tag(config=True) 

179 

180 def _init_resources(self, resources): 

181 resources = super()._init_resources(resources) 

182 if "reveal" not in resources: 

183 resources["reveal"] = {} 

184 resources["reveal"]["url_prefix"] = self.reveal_url_prefix 

185 resources["reveal"]["theme"] = self.reveal_theme 

186 resources["reveal"]["transition"] = self.reveal_transition 

187 resources["reveal"]["scroll"] = self.reveal_scroll 

188 resources["reveal"]["number"] = self.reveal_number 

189 return resources