1 | """ |
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2 | Asset Tag Helpers |
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3 | |
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4 | Provides functionality for linking an HTML page together with other assets, such as |
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5 | javascripts, stylesheets, and feeds. |
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6 | """ |
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7 | # Last synced with Rails copy at Revision 4103 on Aug 19th, 2006. |
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8 | |
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9 | import os |
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10 | import urlparse |
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11 | from tags import * |
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12 | from routes import request_config |
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13 | |
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14 | # The absolute path of the WebHelpers javascripts directory |
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15 | javascript_path = os.path.join(os.path.dirname(os.path.abspath(__file__)), |
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16 | 'javascripts') |
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17 | |
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18 | # WebHelpers' built-in javascripts. Note: scriptaculous automatically includes all of its |
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19 | # supporting .js files |
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20 | javascript_builtins = ('prototype.js', 'scriptaculous.js') |
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21 | |
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22 | def auto_discovery_link_tag(source, type='rss', **kwargs): |
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23 | """ |
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24 | Returns a link tag allowing browsers and news readers (that support it) to auto-detect |
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25 | an RSS or ATOM feed for current page. |
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26 | |
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27 | ``source`` |
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28 | The URL of the feed. The URL is ultimately prepended with the environment's |
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29 | ``SCRIPT_NAME`` (the root path of the web application), unless the URL is |
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30 | fully-fledged (e.g. http://example.com). |
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31 | |
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32 | ``type`` |
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33 | The type of feed. Specifying 'rss' or 'atom' automatically translates to a type of |
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34 | 'application/rss+xml' or 'application/atom+xml', respectively. Otherwise the type |
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35 | is used as specified. Defaults to 'rss'. |
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36 | |
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37 | Examples:: |
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38 | |
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39 | >>> auto_discovery_link_tag('http://feed.com/feed.xml') |
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40 | '<link href="http://feed.com/feed.xml" rel="alternate" title="RSS" type="application/rss+xml" />' |
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41 | |
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42 | >>> auto_discovery_link_tag('http://feed.com/feed.xml', type='atom') |
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43 | '<link href="http://feed.com/feed.xml" rel="alternate" title="ATOM" type="application/atom+xml" />' |
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44 | |
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45 | >>> auto_discovery_link_tag('app.rss', type='atom', title='atom feed') |
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46 | '<link href="app.rss" rel="alternate" title="atom feed" type="application/atom+xml" />' |
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47 | |
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48 | >>> auto_discovery_link_tag('/app.html', type='text/html') |
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49 | '<link href="/app.html" rel="alternate" title="" type="text/html" />' |
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50 | """ |
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51 | title = '' |
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52 | if type.lower() in ('rss', 'atom'): |
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53 | title = type.upper() |
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54 | type='application/%s+xml' % type.lower() |
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55 | |
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56 | tag_args = dict(rel='alternate', type=type, title=title, |
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57 | href=compute_public_path(source)) |
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58 | kwargs.pop('href', None) |
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59 | kwargs.pop('type', None) |
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60 | tag_args.update(kwargs) |
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61 | return tag('link', **tag_args) |
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62 | |
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63 | def image_tag(source, alt=None, size=None, **options): |
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64 | """ |
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65 | Returns an image tag for the specified ``source``. |
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66 | |
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67 | ``source`` |
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68 | The source URL of the image. The URL is prepended with '/images/', unless its full |
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69 | path is specified. The URL is ultimately prepended with the environment's |
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70 | ``SCRIPT_NAME`` (the root path of the web application), unless the URL is |
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71 | fully-fledged (e.g. http://example.com). A source with no filename extension will |
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72 | be automatically appended with the '.png' extension. |
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73 | |
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74 | ``alt`` |
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75 | The img's alt tag. Defaults to the source's filename, title cased. |
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76 | |
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77 | ``size`` |
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78 | The img's size, specified in the format "XxY". "30x45" becomes |
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79 | width="30", height="45". "x20" becomes height="20". |
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80 | |
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81 | Examples:: |
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82 | |
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83 | >>> image_tag('xml') |
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84 | '<img alt="Xml" src="/images/xml.png" />' |
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85 | |
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86 | >>> image_tag('rss', 'rss syndication') |
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87 | '<img alt="rss syndication" src="/images/rss.png" />' |
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88 | """ |
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89 | options['src'] = compute_public_path(source, 'images', 'png') |
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90 | |
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91 | if not alt: |
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92 | alt = os.path.splitext(os.path.basename(source))[0].title() |
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93 | options['alt'] = alt |
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94 | |
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95 | if size: |
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96 | width, height = size.split('x') |
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97 | if width: |
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98 | options['width'] = width |
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99 | if height: |
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100 | options['height'] = height |
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101 | |
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102 | return tag('img', **options) |
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103 | |
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104 | def javascript_include_tag(*sources, **options): |
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105 | """ |
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106 | Returns script include tags for the specified javascript ``sources``. |
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107 | |
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108 | Each source's URL path is prepended with '/javascripts/' unless their full path is |
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109 | specified. Each source's URL path is ultimately prepended with the environment's |
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110 | ``SCRIPT_NAME`` (the root path of the web application), unless the URL path is a |
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111 | full-fledged URL (e.g. http://example.com). Sources with no filename extension will be |
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112 | appended with the '.js' extension. |
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113 | |
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114 | Optionally includes (prepended) WebHelpers' built-in javascripts when passed the |
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115 | ``builtins=True`` keyword argument. |
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116 | |
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117 | Examples:: |
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118 | |
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119 | >>> print javascript_include_tag(builtins=True) |
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120 | <script src="/javascripts/prototype.js" type="text/javascript"></script> |
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121 | <script src="/javascripts/scriptaculous.js" type="text/javascript"></script> |
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122 | |
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123 | >>> print javascript_include_tag('prototype', '/other-javascripts/util.js') |
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124 | <script src="/javascripts/prototype.js" type="text/javascript"></script> |
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125 | <script src="/other-javascripts/util.js" type="text/javascript"></script> |
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126 | |
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127 | >>> print javascript_include_tag('app', '/test/test.1.js', builtins=True) |
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128 | <script src="/javascripts/prototype.js" type="text/javascript"></script> |
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129 | <script src="/javascripts/scriptaculous.js" type="text/javascript"></script> |
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130 | <script src="/javascripts/app.js" type="text/javascript"></script> |
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131 | <script src="/test/test.1.js" type="text/javascript"></script> |
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132 | """ |
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133 | if options.get('builtins'): |
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134 | sources = javascript_builtins + sources |
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135 | |
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136 | tags = [content_tag('script', None, |
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137 | **dict(type='text/javascript', |
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138 | src=compute_public_path(source, 'javascripts', 'js'))) \ |
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139 | for source in sources] |
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140 | return '\n'.join(tags) |
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141 | |
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142 | def stylesheet_link_tag(*sources, **options): |
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143 | """ |
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144 | Returns CSS link tags for the specified stylesheet ``sources``. |
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145 | |
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146 | Each source's URL path is prepended with '/stylesheets/' unless their full path is |
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147 | specified. Each source's URL path is ultimately prepended with the environment's |
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148 | ``SCRIPT_NAME`` (the root path of the web application), unless the URL path is a |
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149 | full-fledged URL (e.g. http://example.com). Sources with no filename extension will be |
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150 | appended with the '.css' extension. |
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151 | |
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152 | Examples:: |
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153 | |
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154 | >>> stylesheet_link_tag('style') |
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155 | '<link href="/stylesheets/style.css" media="screen" rel="Stylesheet" type="text/css" />' |
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156 | |
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157 | >>> stylesheet_link_tag('/dir/file', media='all') |
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158 | '<link href="/dir/file.css" media="all" rel="Stylesheet" type="text/css" />' |
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159 | """ |
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160 | tag_options = dict(rel='Stylesheet', type='text/css', media='screen') |
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161 | tag_options.update(options) |
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162 | tag_options.pop('href', None) |
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163 | |
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164 | tags = [tag('link', **dict(href=compute_public_path(source, 'stylesheets', 'css'), |
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165 | **tag_options)) for source in sources] |
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166 | return '\n'.join(tags) |
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167 | |
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168 | def compute_public_path(source, root_path=None, ext=None): |
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169 | """ |
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170 | Format the specified source for publishing, via the public directory, if applicable. |
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171 | """ |
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172 | if ext and not os.path.splitext(os.path.basename(source))[1]: |
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173 | source = '%s.%s' % (source, ext) |
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174 | |
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175 | # Avoid munging fully-fledged URLs, including 'mailto:' |
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176 | parsed = urlparse.urlparse(source) |
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177 | if not (parsed[0] and (parsed[1] or parsed[2])): |
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178 | # Prefix apps deployed under any SCRIPT_NAME path |
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179 | if not root_path or source.startswith('/'): |
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180 | source = '%s%s' % (get_script_name(), source) |
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181 | else: |
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182 | source = '%s/%s/%s' % (get_script_name(), root_path, source) |
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183 | return source |
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184 | |
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185 | def get_script_name(): |
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186 | """ |
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187 | Determine the current web application's ``SCRIPT_NAME``. |
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188 | """ |
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189 | script_name = '' |
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190 | config = request_config() |
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191 | if hasattr(config, 'environ'): |
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192 | script_name = config.environ.get('SCRIPT_NAME', '') |
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193 | return script_name |
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194 | |
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195 | __all__ = ['javascript_path', 'javascript_builtins', 'auto_discovery_link_tag', |
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196 | 'image_tag', 'javascript_include_tag', 'stylesheet_link_tag'] |
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