Added explanation for tests

lod/SPARQL.ipynb

@@ -1872,7 +1872,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.6.4"
+   "version": "3.7.2"
   }
  },
  "nbformat": 4,

rdf/helpers.py

@@ -0,0 +1,148 @@
+import sys
+import operator
+import types
+from future.standard_library import install_aliases
+install_aliases()
+
+from urllib import request, parse
+from rdflib import Graph, term, Namespace, BNode
+from lxml import etree
+
+import IPython
+js = "IPython.CodeCell.options_default.highlight_modes['magic_turtle'] = {'reg':[/^%%ttl/]};"
+IPython.core.display.display_javascript(js, raw=True)
+
+
+from IPython.core.magic import (register_line_magic, register_cell_magic,
+                                register_line_cell_magic)
+from IPython.display import HTML, display, Image, Markdown
+
+
+schema = Namespace('http://schema.org/')
+
+DEFINITIONS = {}
+
+def solution(exercise='default'):
+    if exercise not in DEFINITIONS:
+        raise Exception('Solution for {} not found'.format(exercise))
+    return DEFINITIONS[exercise]
+
+
+@register_cell_magic
+def ttl(line, cell):
+    '''
+    TTL magic command for ipython. It can be used in a cell like this:
+    
+    ```
+    %%ttl
+    
+    ... Your TTL definition ...
+    
+    ```
+    The definition will be loaded into a DEFINITION variable, using RDFlib.
+    This definition can then be used for evaluation.
+    '''
+    g = Graph()
+    msg = '''Error on line {line}
+
+Reason: {reason}
+
+If you don\'t know what this error means, try an online validator: http://ttl.summerofcode.be/
+'''
+    global DEFINITIONS
+    key = line or 'default'
+    try:
+        DEFINITIONS[key] = g.parse(data=cell,
+                                  format="n3")
+    except SyntaxError as ex:
+        return Markdown(msg.format(line=ex.lines, reason=ex._why))
+    except Exception as ex:
+        return Markdown(msg.format(line='?', reason=ex))
+    return Markdown('File loaded!')
+        
+    return HTML('Loaded!') #HTML('<code>{}</code>'.format(cell))
+
+
+def extract_data(url):
+    g = Graph()
+    try:
+        g.parse(url, format='rdfa')
+    except Exception:
+        print('Could not get rdfa data', file=sys.stderr)
+    try:
+        g.parse(url, format='microdata')
+    except Exception:
+        print('Could not get microdata', file=sys.stderr)
+
+
+    def sanitize_triple(t):
+        """Function to remove bad URIs from the graph that would otherwise
+        make the serialization fail."""
+        def sanitize_triple_item(item):
+            if isinstance(item, term.URIRef) and ' ' in item:
+                return term.URIRef(parse.quote(str(item)))
+            return item
+
+        return (sanitize_triple_item(t[0]),
+                sanitize_triple_item(t[1]),
+                sanitize_triple_item(t[2]))
+
+
+    with request.urlopen(url) as response:
+        # Get all json-ld objects embedded in the html file
+        html = response.read().decode('utf-8', errors='ignore')
+        parser = etree.XMLParser(recover=True)
+        root = etree.fromstring(html.encode(), parser=parser)
+        if root is not None and len(root):
+            for jsonld in root.findall(".//script[@type='application/ld+json']"):
+                g.parse(data=jsonld.text, publicID=BNode(), format='json-ld')
+
+
+    fixedgraph = Graph()
+    fixedgraph += [sanitize_triple(s) for s in g]
+
+#     print(g.serialize(format='turtle').decode('utf-8', errors='ignore'))
+    return fixedgraph
+
+def turtle(g):
+    return Markdown('''
+Results:
+
+```turtle
+{}
+```
+'''.format(g.serialize(format='turtle').decode('utf-8', errors='ignore')))
+
+def print_data(url):
+    g = extract_data(url)
+    return turtle(g)
+
+    
+
+def test(description, got, expected=None, func=None):
+    if isinstance(got, types.GeneratorType):
+        got = set(got)
+    try:
+        if expected is None:
+            func = func or operator.truth
+            expected = True
+            assert func(got)
+        else:
+            func = func or operator.eq
+            assert func(got, expected)
+    except AssertionError:
+        print('Test failed: {}'.format(description), file=sys.stderr)
+        print('\tExpected: {}'.format(expected), file=sys.stderr)
+        print('\tGot:      {}'.format(got), file=sys.stderr)
+        raise Exception('Test failed: {}'.format(description))
+
+        
+def atLeast(lst, number):
+    return len(set(lst))>=number
+
+def containsAll(lst, other):
+    for i in other:
+        if i not in lst:
+            print('{} not found'.format(i), file=sys.stderr)
+            return False
+    return True