Cleanup and addresses PR comments

Author: Ralf Grubenmann

renku/core/commands/checks/validate_shacl.py

@@ -37,15 +37,17 @@ def _shacl_graph_to_string(graph):
         res = graph.value(result, sh.resultMessage)
 
         if res:
-            message = '{}: {}'.format(path, res)
+            message = '{0}: {1}'.format(path, res)
         else:
             kind = graph.value(result, sh.sourceConstraintComponent)
             focusNode = graph.value(result, sh.focusNode)
 
             if isinstance(focusNode, BNode):
                 focusNode = '<Anonymous>'
 
-            message = '{}: Type: {}, Node ID: {}'.format(path, kind, focusNode)
+            message = '{0}: Type: {1}, Node ID: {2}'.format(
+                path, kind, focusNode
+            )
 
         problems.append(message)
 
@@ -61,9 +63,8 @@ def check_project_structure(client):
     if conform:
         return True, None
 
-    problems = (
-        WARNING + 'Invalid structure of project metadata\n\t' +
-        _shacl_graph_to_string(graph)
+    problems = '{0}Invalid structure of project metadata\n\t{1}'.format(
+        WARNING, _shacl_graph_to_string(graph)
     )
 
     return False, problems
@@ -73,26 +74,28 @@ def check_datasets_structure(client):
     """Validate dataset metadata against SHACL."""
     ok = True
 
-    problems = WARNING + 'Invalid structure of dataset metadata\n'
+    problems = ['{0}Invalid structure of dataset metadata'.format(WARNING)]
 
     for path in client.renku_datasets_path.rglob(client.METADATA):
         try:
             conform, graph, t = check_shacl_structure(path)
         except (Exception, BaseException) as e:
-            problems += 'Couldn\'t validate {}: {}\n\n'.format(path, e)
+            problems.append('Couldn\'t validate {0}: {1}\n\n'.format(path, e))
             continue
 
         if conform:
             continue
 
         ok = False
 
-        problems += str(path) + '\n\t' + _shacl_graph_to_string(graph) + '\n\n'
+        problems.append(
+            '{0}\n\t{1}\n'.format(path, _shacl_graph_to_string(graph))
+        )
 
     if ok:
         return True, None
 
-    return False, problems
+    return False, '\n'.join(problems)
 
 
 def check_shacl_structure(path):

renku/core/commands/format/graph.py

@@ -21,6 +21,7 @@
 
 import click
 
+from renku.core.errors import SHACLValidationError
 from renku.core.utils.shacl import validate_graph
 
 
@@ -30,7 +31,7 @@ def ascii(graph, strict=False):
     from ..echo import echo_via_pager
 
     if strict:
-        raise click.BadParameter('--strict not supported for json-ld-graph')
+        raise SHACLValidationError('--strict not supported for json-ld-graph')
 
     echo_via_pager(str(DAG(graph)))
 
@@ -68,7 +69,7 @@ def dot(graph, simple=True, debug=False, landscape=False, strict=False):
     from rdflib.tools.rdf2dot import rdf2dot
 
     if strict:
-        raise click.BadParameter('--strict not supported for json-ld-graph')
+        raise SHACLValidationError('--strict not supported for json-ld-graph')
 
     g = _conjunctive_graph(graph)
 
@@ -312,7 +313,7 @@ def makefile(graph, strict=False):
     from renku.core.models.provenance.activities import ProcessRun, WorkflowRun
 
     if strict:
-        raise click.BadParameter('--strict not supported for json-ld-graph')
+        raise SHACLValidationError('--strict not supported for json-ld-graph')
 
     for activity in graph.activities.values():
         if not isinstance(activity, ProcessRun):
@@ -341,7 +342,7 @@ def jsonld(graph, strict=False):
         r, _, t = validate_graph(ld, format='json-ld')
 
         if not r:
-            raise click.BadParameter(
+            raise SHACLValidationError(
                 "{}\nCouldn't get log: Invalid Knowledge Graph data".format(t)
             )
     click.echo(ld)
@@ -350,7 +351,7 @@ def jsonld(graph, strict=False):
 def jsonld_graph(graph, strict=False):
     """Format graph as JSON-LD graph file."""
     if strict:
-        raise click.BadParameter('--strict not supported for json-ld-graph')
+        raise SHACLValidationError('--strict not supported for json-ld-graph')
     click.echo(_jsonld(graph, 'flatten'))
 
 
@@ -361,7 +362,7 @@ def nt(graph, strict=False):
         r, _, t = validate_graph(nt, format='nt')
 
         if not r:
-            raise click.BadParameter(
+            raise SHACLValidationError(
                 "{}\nCouldn't get log: Invalid Knowledge Graph data".format(t)
             )
 
@@ -375,7 +376,7 @@ def rdf(graph, strict=False):
         r, _, t = validate_graph(xml, format='xml')
 
         if not r:
-            raise click.BadParameter(
+            raise SHACLValidationError(
                 "{}\nCouldn't get log: Invalid Knowledge Graph data".format(t)
             )
 

renku/core/errors.py

@@ -373,3 +373,7 @@ class UrlSchemeNotSupported(RenkuException):
 
 class OperationError(RenkuException):
     """Raised when an operation at runtime raises an error."""
+
+
+class SHACLValidationError(RenkuException):
+    """Raises when SHACL validation of the graph fails."""

renku/core/utils/shacl.py

@@ -15,7 +15,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-"""JSON-LD SHACL validation."""
+"""JSON-LD SHACL validations."""
 
 from pkg_resources import resource_string
 from pyshacl import validate
@@ -24,7 +24,7 @@
 def validate_graph(graph, shacl_path=None, format='nquads'):
     """Validate the current graph with a SHACL schema.
 
-    uses default schema if not supplied.
+    Uses default schema if not supplied.
     """
     if shacl_path:
         with open(shacl_path, 'r', encoding='utf-8') as f: