add blockly_magic

Author: ChrisJaunes

metakernel/magics/blockly_magic.py

@@ -0,0 +1,106 @@
+# Copyright (c) Metakernel Development Team.
+# Distributed under the terms of the Modified BSD License.
+
+from metakernel import Magic, option
+from IPython.display import IFrame, Javascript
+import string
+import random
+import os
+
+
+class BlocklyMagic(Magic):
+
+    @option(
+        '-o', '--html_from_origin', action='store', default=None,
+        help='use the provided name as filename of html origin'
+    )
+    @option(
+        '-l', '--html_from_local', action='store', default=None,
+        help='use the provided name as filename of html page'
+    )
+    @option(
+        '-t', '--template_data', action='store', default=None,
+        help='generate page based on template, must be used with parameters(-ho or -hl)'
+             'use the provided name as workspace filename\n example : -ht xxx \n local include file: \n\txxx-toolbox.xml \n\txxx-workspace.xml \n\txxx-blocks.js'
+    )
+    @option(
+        '-h', '--height', action='store', default=350,
+        help='set height of iframe '
+    )
+    def line_blockly(self, html_from_origin=None, html_from_local=None, template_data=None, height=350):
+        """
+        %blockly - show visual code
+
+        This line magic will allow visual code editing
+
+        Examples:
+            %blockly --html_from_origin http://host:port/blockly_page.html
+            %blockly --html_from_local blockly_page.html
+            %blockly --html_from_origin http://host:port/blockly_template.html --template_data template_data
+        """
+        # Display iframe:
+        script = """
+        if(document.receiveBlocklyPythonCode === undefined) {
+            document.receiveBlocklyPythonCode = function ( event ) {
+                //console.log( 'receiveMessage[Index]', event );
+                IPython.notebook.insert_cell_at_index(0, 2).set_text(event.data);
+            }
+            window.addEventListener("message", document.receiveBlocklyPythonCode, false)
+        }
+        """
+        #print(script)
+        self.kernel.Display(Javascript(script))
+        if height is None:
+            height = 350
+        if template_data is not None:
+            if html_from_origin is not None:
+                try:
+                    import urllib.request
+                    urlopen = urllib.request.urlopen
+                except:  # python2
+                    import urllib
+                    urlopen = urllib.urlopen
+                html_template = urlopen(html_from_origin).read().decode("utf-8")
+            elif html_from_local is not None:
+                with open(html_from_local, "rb") as fp:
+                    html_template = fp.read().decode("utf-8")
+            else:
+                raise
+            with open(template_data+'-toolbox.xml', "rb") as fp:
+                blockly_toolbar = fp.read().decode("utf-8")
+            with open(template_data + '-workspace.xml', "rb") as fp:
+                blockly_workspace = fp.read().decode("utf-8")
+            with open(template_data + '-blocks.js', "rb") as fp:
+                blockly_blocks = fp.read().decode("utf-8")
+            html_template = html_template.replace("MY_BLOCKLY_TOOLBAR", blockly_toolbar)
+            html_template = html_template.replace("MY_BLOCKLY_WORKSPACE", blockly_workspace)
+            html_template = html_template.replace("MY_BLOCKLY_BLOCKS", blockly_blocks)
+            with open(template_data + '.html', 'w') as fp:
+                fp.write(html_template)
+            html_from_local = template_data + '.html'
+        if html_from_local is not None:
+            self.kernel.Display(IFrame(html_from_local, width='100%', height=height))
+        elif html_from_origin is not None:
+            self.kernel.Display(IFrame(html_from_origin, width='100%', height=height))
+        else:
+            raise
+
+
+def register_magics(kernel):
+    kernel.register_magics(Magic)
+
+
+def register_ipython_magics():
+    from metakernel import IPythonKernel
+    from IPython.core.magic import register_line_magic
+    kernel = IPythonKernel()
+    magic = BlocklyMagic(kernel)
+    # Make magics callable:
+    kernel.line_magics["blockly"] = magic
+
+    @register_line_magic
+    def blockly(line):
+        """
+        Use the blockly code visualizer and generator.
+        """
+        kernel.call_magic("%blockly " + line)