Switch generate_schema to default to OpenAPI

rest_framework/management/commands/generate_schema.py

@@ -1,9 +1,102 @@
 from django.core.management.base import BaseCommand
 
+from rest_framework.compat import coreapi, coreschema
 from rest_framework.renderers import CoreJSONRenderer, JSONRenderer
 from rest_framework.schemas.generators import OpenAPISchemaGenerator
 from rest_framework.settings import api_settings
 
+import json
+import urllib.parse as urlparse
+
+
+class OpenAPICodec:
+    CLASS_TO_TYPENAME = {
+        coreschema.Object: 'object',
+        coreschema.Array: 'array',
+        coreschema.Number: 'number',
+        coreschema.Integer: 'integer',
+        coreschema.String: 'string',
+        coreschema.Boolean: 'boolean',
+    }
+
+    def get_schema(self, instance):
+        schema = {}
+        if instance.__class__ in self.CLASS_TO_TYPENAME:
+            schema['type'] = self.CLASS_TO_TYPENAME[instance.__class__]
+        schema['title'] = instance.title,
+        schema['description'] = instance.description
+        if hasattr(instance, 'enum'):
+            schema['enum'] = instance.enum
+        return schema
+
+    def get_parameters(self, link):
+        parameters = []
+        for field in link.fields:
+            if field.location not in ['path', 'query']:
+                continue
+            parameter = {
+                'name': field.name,
+                'in': field.location,
+            }
+            if field.required:
+                parameter['required'] = True
+            if field.description:
+                parameter['description'] = field.description
+            if field.schema:
+                parameter['schema'] = self.get_schema(field.schema)
+            parameters.append(parameter)
+        return parameters
+
+    def get_operation(self, link, name, tag):
+        operation_id = "%s_%s" % (tag, name) if tag else name
+        parameters = self.get_parameters(link)
+
+        operation = {
+            'operationId': operation_id,
+        }
+        if link.title:
+            operation['summary'] = link.title
+        if link.description:
+            operation['description'] = link.description
+        if parameters:
+            operation['parameters'] = parameters
+        if tag:
+            operation['tags'] = [tag]
+        return operation
+
+    def get_paths(self, document):
+        paths = {}
+
+        tag = None
+        for name, link in document.links.items():
+            path = urlparse.urlparse(link.url).path
+            method = link.action.lower()
+            paths.setdefault(path, {})
+            paths[path][method] = self.get_operation(link, name, tag=tag)
+
+        for tag, section in document.data.items():
+            for name, link in section.links.items():
+                path = urlparse.urlparse(link.url).path
+                method = link.action.lower()
+                paths.setdefault(path, {})
+                paths[path][method] = self.get_operation(link, name, tag=tag)
+
+        return paths
+
+    def encode(self, document):
+        return json.dumps({
+            'openapi': '3.0.0',
+            'info': {
+                'version': '',
+                'title': document.title,
+                'description': document.description
+            },
+            'servers': [{
+                'url': document.url
+            }],
+            'paths': self.get_paths(document)
+        }, indent=4)
+
 
 class Command(BaseCommand):
     help = "Generates configured API schema for project."
@@ -27,15 +120,19 @@ class Command(BaseCommand):
         pass
 
     def handle(self, *args, **options):
+        assert coreapi is not None, 'coreapi must be installed.'
+
         generator_class = self._get_generator_class()
         generator = generator_class()
 
         schema = generator.get_schema(request=None, public=True)
+        codec = OpenAPICodec()
 
-        renderer = self._get_renderer(generator)
-        rendered_schema = renderer.render(schema, renderer_context={}).decode('utf8')
+        #renderer = self._get_renderer(generator)
+        #rendered_schema = renderer.render(schema, renderer_context={}).decode('utf8')
+        output = codec.encode(schema)
 
-        self.stdout.write(rendered_schema)
+        self.stdout.write(output)
 
     def _get_generator_class(self):
         return api_settings.DEFAULT_SCHEMA_GENERATOR_CLASS