Initial implementation of JSON validation with schema in GenericJsonParser

Author: Funkenjaeger

InteractiveHtmlBom/ecad/genericjson.py

@@ -1,5 +1,6 @@
 import io
 import json
+from jsonschema import validate, ValidationError
 
 from .common import EcadParser, Component
 
@@ -8,36 +9,47 @@ class GenericJsonParser(EcadParser):
     COMPATIBLE_SPEC_VERSIONS = [1]
 
     def get_generic_json_pcb(self):
+        from os import path
         with io.open(self.file_name, 'r') as f:
-            return json.load(f)
+            pcb = json.load(f)
 
-    def _verify(self, pcb):
+        if '_spec_version' not in pcb:
+            raise ValidationError("'_spec_version' is a required property")
 
-        """Spot check the pcb object."""
-        if 'pcbdata' not in pcb:
-            self.logger.error('No pcbdata object')
-            return False
-        p = pcb['pcbdata']
+        if pcb['_spec_version'] not in self.COMPATIBLE_SPEC_VERSIONS:
+            raise ValidationError("Unsupported _spec_version ({})"
+                                  .format(pcb['_spec_version']))
 
-        if 'components' not in pcb:
-            self.logger.error('No components object')
-            return False
-        c = pcb['components']
+        schema_dir = path.join(path.dirname(__file__), 'schema')
+        if pcb['_spec_version'] == 1:
+            schema_file_name = path.join(schema_dir,
+                                         'genericjsonpcbdata_v{}.schema'
+                                         .format(pcb['_spec_version']))
 
-        if pcb['_spec_version'] not in self.COMPATIBLE_SPEC_VERSIONS:
-            self.logger.error('Unsupported spec version ({})'
-                              .format(pcb['_spec_version']))
-            return False
+        with io.open(schema_file_name, 'r') as f:
+            schema = json.load(f)
 
-        if 'footprints' not in p or len(p['footprints']) != len(c):
+        validate(instance=pcb, schema=schema)
+
+        return pcb
+
+    def _verify(self, pcb):
+
+        """Spot check the pcb object."""
+
+        if len(pcb['pcbdata']['footprints']) != len(pcb['components']):
             self.logger.error("length of components list doesn't match"
                               " length of footprints list")
             return False
 
         return True
 
     def parse(self):
-        pcb = self.get_generic_json_pcb()
+        try:
+            pcb = self.get_generic_json_pcb()
+        except ValidationError as e:
+            self.logger.error(e.message)
+            return None, None
 
         if not self._verify(pcb):
             self.logger.error('File {} does not appear to be valid generic'