Add basic renderers

examples/test.py

@@ -0,0 +1,2 @@
+import this
+foo = 'lol'

main.py

@@ -1,19 +1,75 @@
-from flask import Flask
+from flask import Flask, request, send_file, send_from_directory
+from cStringIO import StringIO
+import importlib
 import os
 
-app = Flask(__name__)
+from renderer import FileRenderer
+
+app = Flask(__name__, static_folder='examples')
+
+# Recursively import modules
+for dirpath, dirnames, filenames in os.walk('renderer'):
+    for filename in filenames:
+        if filename.endswith('.py'):
+            modulename = os.path.join(dirpath, filename)\
+                .replace('/', '.')\
+                .replace('.py', '')
+            importlib.import_module(modulename)
+
+# Optional configuration for renderers
+config = {
+    'ImageRenderer': {'max_width': '200px'},
+}
+
+# Module static files should live in renderer/<module/static
+@app.route('/static/<module>/<path:filepath>')
+def send_module_file(module, filepath):
+    path, filename = os.path.split(filepath)
+    module_static_dir = os.path.join('renderer', module, 'static', path)
+    return send_from_directory(module_static_dir, filename)
+
+@app.route('/export/<renderer>/<filename>/', methods=['POST'])
+def export(renderer, filename):
+    exporter = request.form.get('exporter')
+    renderer_class = FileRenderer.registry.get(renderer)
+    if renderer_class is None:
+        return 'Renderer not found.'
+    renderer_object = renderer_class(**config.get(renderer, {}))
+    renderer_method = getattr(
+        renderer_object, 
+        'export_{}'.format(exporter), 
+        None
+    )
+    if renderer_method is None:
+        return 'Renderer exporter not found.'
+    filepath = os.path.join('examples', filename)
+    rendered, extension = renderer_method(open(filepath))
+
+    name, ext = os.path.splitext(filename)
+    export_name = name + extension
+
+    return send_file(
+        StringIO(rendered),
+        as_attachment=True,
+        attachment_filename=export_name,
+    )
 
 @app.route('/')
 def index():
     html = ''
     for fn in os.listdir('examples'):
-        html += '<a href="/example/{filename}">{filename}</a><br />'.format(
+        html += '<a href="/render/{filename}">{filename}</a><br />'.format(
             filename=fn)
     return html
 
-@app.route('/example/<filename>')
-def examples(filename):
+@app.route('/render/<filename>')
+def render(filename):
+    fp = open(os.path.join('examples', filename))
+    for name, cls in FileRenderer.registry.items():
+        renderer = cls(**config.get(name, {}))
+        if renderer.detect(fp):
+            return renderer._render(fp, '/examples/{}'.format(filename))
     return filename
 
 if __name__ == '__main__':
-    app.run(debug=True)
+    app.run(debug=True, port=5001)

renderer/__init__.py

@@ -0,0 +1,86 @@
+import os
+import abc
+import inspect
+
+class FileMeta(abc.ABCMeta):
+
+    def __init__(cls, name, bases, dct):
+
+        # Call super-metaclass __init__
+        super(FileMeta, cls).__init__(name, bases, dct)
+
+        # Initialize class registry and add self
+        if not hasattr(cls, 'registry'):
+            cls.registry = {}
+        if name != 'FileRenderer':
+            cls.registry[name] = cls
+
+        # Get export methods
+        cls.exporters = [
+            name.replace('export_', '')
+            for name, value in dct.iteritems()
+            if name.startswith('export_')
+                and inspect.isfunction(value)
+        ]
+
+class FileRenderer(object):
+
+    __metaclass__ = FileMeta
+
+    def _render(self, fp, path):
+
+        _, filename = os.path.split(fp.name)
+        exporters = self.render_exporters(filename)
+        rendered = self.render(fp, path)
+        return exporters + '\n' + rendered
+
+    def render_exporters(self, filename):
+        """Render exporters to an HTML form.
+
+        :param filename: Name of file to export
+        :return: HTML form with dropdown widget
+
+        """
+        if not self.exporters:
+            return ''
+
+        options = [
+            '<option value="{}">{}</option>'.format(
+                exporter, exporter.capitalize()
+            )
+            for exporter in self.exporters
+        ]
+
+        return '''
+        <form method="post" action="/export/{klass}/{filename}/">
+            <select name="exporter">
+                {options}
+            </select>
+            <input type="submit" value="Submit" />
+        </form>'''.format(
+            klass=self.__class__.__name__,
+            filename=filename,
+            options='\n'.join(options)
+        )
+
+    @abc.abstractmethod
+    def detect(self, fp):
+        """Detects whether a given file pointer can be rendered by 
+        this renderer.
+
+        :param fp: File pointer
+        :return: Can file be rendered? (bool)
+
+        """
+        pass
+
+    @abc.abstractmethod
+    def render(self, fp, path):
+        """Renders a file to HTML.
+
+        :param fp: File pointer
+        :param path: Path to file
+        :return: HTML rendition of file
+
+        """
+        pass

renderer/code/__init__.py

@@ -0,0 +1,25 @@
+from .. import FileRenderer
+
+import pygments
+import pygments.lexers
+import pygments.formatters
+
+formatter = pygments.formatters.HtmlFormatter()
+
+class CodeRenderer(FileRenderer):
+
+    def detect(self, fp):
+        fname = fp.name
+        for ext in ['py', 'rb']:
+            if fname.endswith(ext):
+                return True
+        return False
+
+    def render(self, fp, path):
+        content = fp.read()
+        highlight = pygments.highlight(
+            content,
+            pygments.lexers.guess_lexer_for_filename(fp.name, content),
+            formatter
+        )
+        return '<link rel="stylesheet" href="/static/code/css/style.css" />' + '\n' + highlight

renderer/code/static/css/style.css

@@ -0,0 +1,62 @@
+.highlight .hll { background-color: #ffffcc }
+.highlight  { background: #f8f8f8; }
+.highlight .c { color: #408080; font-style: italic } /* Comment */
+.highlight .err { border: 1px solid #FF0000 } /* Error */
+.highlight .k { color: #008000; font-weight: bold } /* Keyword */
+.highlight .o { color: #666666 } /* Operator */
+.highlight .cm { color: #408080; font-style: italic } /* Comment.Multiline */
+.highlight .cp { color: #BC7A00 } /* Comment.Preproc */
+.highlight .c1 { color: #408080; font-style: italic } /* Comment.Single */
+.highlight .cs { color: #408080; font-style: italic } /* Comment.Special */
+.highlight .gd { color: #A00000 } /* Generic.Deleted */
+.highlight .ge { font-style: italic } /* Generic.Emph */
+.highlight .gr { color: #FF0000 } /* Generic.Error */
+.highlight .gh { color: #000080; font-weight: bold } /* Generic.Heading */
+.highlight .gi { color: #00A000 } /* Generic.Inserted */
+.highlight .go { color: #888888 } /* Generic.Output */
+.highlight .gp { color: #000080; font-weight: bold } /* Generic.Prompt */
+.highlight .gs { font-weight: bold } /* Generic.Strong */
+.highlight .gu { color: #800080; font-weight: bold } /* Generic.Subheading */
+.highlight .gt { color: #0044DD } /* Generic.Traceback */
+.highlight .kc { color: #008000; font-weight: bold } /* Keyword.Constant */
+.highlight .kd { color: #008000; font-weight: bold } /* Keyword.Declaration */
+.highlight .kn { color: #008000; font-weight: bold } /* Keyword.Namespace */
+.highlight .kp { color: #008000 } /* Keyword.Pseudo */
+.highlight .kr { color: #008000; font-weight: bold } /* Keyword.Reserved */
+.highlight .kt { color: #B00040 } /* Keyword.Type */
+.highlight .m { color: #666666 } /* Literal.Number */
+.highlight .s { color: #BA2121 } /* Literal.String */
+.highlight .na { color: #7D9029 } /* Name.Attribute */
+.highlight .nb { color: #008000 } /* Name.Builtin */
+.highlight .nc { color: #0000FF; font-weight: bold } /* Name.Class */
+.highlight .no { color: #880000 } /* Name.Constant */
+.highlight .nd { color: #AA22FF } /* Name.Decorator */
+.highlight .ni { color: #999999; font-weight: bold } /* Name.Entity */
+.highlight .ne { color: #D2413A; font-weight: bold } /* Name.Exception */
+.highlight .nf { color: #0000FF } /* Name.Function */
+.highlight .nl { color: #A0A000 } /* Name.Label */
+.highlight .nn { color: #0000FF; font-weight: bold } /* Name.Namespace */
+.highlight .nt { color: #008000; font-weight: bold } /* Name.Tag */
+.highlight .nv { color: #19177C } /* Name.Variable */
+.highlight .ow { color: #AA22FF; font-weight: bold } /* Operator.Word */
+.highlight .w { color: #bbbbbb } /* Text.Whitespace */
+.highlight .mf { color: #666666 } /* Literal.Number.Float */
+.highlight .mh { color: #666666 } /* Literal.Number.Hex */
+.highlight .mi { color: #666666 } /* Literal.Number.Integer */
+.highlight .mo { color: #666666 } /* Literal.Number.Oct */
+.highlight .sb { color: #BA2121 } /* Literal.String.Backtick */
+.highlight .sc { color: #BA2121 } /* Literal.String.Char */
+.highlight .sd { color: #BA2121; font-style: italic } /* Literal.String.Doc */
+.highlight .s2 { color: #BA2121 } /* Literal.String.Double */
+.highlight .se { color: #BB6622; font-weight: bold } /* Literal.String.Escape */
+.highlight .sh { color: #BA2121 } /* Literal.String.Heredoc */
+.highlight .si { color: #BB6688; font-weight: bold } /* Literal.String.Interpol */
+.highlight .sx { color: #008000 } /* Literal.String.Other */
+.highlight .sr { color: #BB6688 } /* Literal.String.Regex */
+.highlight .s1 { color: #BA2121 } /* Literal.String.Single */
+.highlight .ss { color: #19177C } /* Literal.String.Symbol */
+.highlight .bp { color: #008000 } /* Name.Builtin.Pseudo */
+.highlight .vc { color: #19177C } /* Name.Variable.Class */
+.highlight .vg { color: #19177C } /* Name.Variable.Global */
+.highlight .vi { color: #19177C } /* Name.Variable.Instance */
+.highlight .il { color: #666666 } /* Literal.Number.Integer.Long */

renderer/image/__init__.py

@@ -0,0 +1,35 @@
+from .. import FileRenderer
+from cStringIO import StringIO
+import Image
+
+class ImageRenderer(FileRenderer):
+
+    def __init__(self, max_width=None):
+        self.max_width = max_width
+
+    def detect(self, fp):
+        fname = fp.name
+        for ext in ['jpg', 'png', 'tif']:
+            if fname.endswith(ext):
+                return True
+        return False
+
+    def render(self, fp, path):
+        fname = fp.name
+        if self.max_width:
+            style = ' style="max-width: {}"'.format(self.max_width)
+        else:
+            style = ''
+        return '<img src="{}"{} />'.format(path, style)
+
+    def export_gif(self, fp):
+        im = Image.open(fp)
+        sio = StringIO()
+        im.save(sio, format='gif')
+        return sio.getvalue(), '.gif'
+
+    def export_tiff(self, fp):
+        im = Image.open(fp)
+        sio = StringIO()
+        im.save(sio, format='tiff')
+        return sio.getvalue(), '.tiff'

renderer/pdf/__init__.py

@@ -1,2 +1,23 @@
-class PdfRenderer(object):
-    pass
+from .. import FileRenderer
+
+class PdfRenderer(FileRenderer):
+
+    def detect(self, fp):
+        return fp.name.endswith('pdf')
+
+    def render(self, fp, path):
+        return '''
+
+            <!-- Include PDF.JS -->
+            <script type="text/javascript src="/static/pdf/js/pdf.js"></script>
+            <script type="text/javascript src="/static/pdf/js/???"></script>
+
+            <script type="text/javascript">
+                var pdf = PDFJS.getDocument('{url}');
+                pdf.then(renderPage);
+            </script>
+
+            <div id="pdfContainer"></div>
+        '''.format(
+            url='path/to/pdf'
+        )

renderer/pdf/static/js/pdf.js

@@ -0,0 +1 @@
+someone set up us the bomb

renderer/text/__init__.py

@@ -0,0 +1,20 @@
+from .. import FileRenderer
+
+class TextRenderer(FileRenderer):
+
+    def detect(self, fp):
+        fname = fp.name
+        for ext in ['txt']:
+            if fname.endswith(ext):
+                return True
+        return False
+
+    def render(self, fp, path):
+        fname = fp.name
+        return '<pre>{}</pre>'.format(fp.read())
+
+    def export_text(self, fp):
+        return fp.read(), '.txt'
+
+    def export_blah(self, fp):
+        return fp.read(), '.bla'

requirements.txt

@@ -0,0 +1,8 @@
+Flask==0.10.1
+Jinja2==2.7.1
+MarkupSafe==0.18
+PIL==1.1.7
+Pygments==1.6
+Werkzeug==0.9.4
+itsdangerous==0.23
+wsgiref==0.1.2