OAS2 converter: handle minLength, maxLength and pattern

modules/swagger-parser-v2-converter/src/main/java/io/swagger/v3/parser/converter/SwaggerConverter.java

@@ -27,6 +27,7 @@
 import io.swagger.models.properties.ObjectProperty;
 import io.swagger.models.properties.Property;
 import io.swagger.models.properties.RefProperty;
+import io.swagger.models.properties.StringProperty;
 import io.swagger.parser.SwaggerParser;
 import io.swagger.parser.SwaggerResolver;
 import io.swagger.parser.util.SwaggerDeserializationResult;
@@ -873,6 +874,14 @@ private Schema convert(Property schema) {
                 result.setExclusiveMaximum(np.getExclusiveMaximum());
                 result.setExclusiveMinimum(np.getExclusiveMinimum());
             }
+
+            if (schema instanceof StringProperty) {
+                StringProperty sp = (StringProperty) schema;
+
+                result.setMinLength(sp.getMinLength());
+                result.setMaxLength(sp.getMaxLength());
+                result.setPattern(sp.getPattern());
+            }
         }
 
         if (schema.getVendorExtensions() != null) {

modules/swagger-parser-v2-converter/src/test/java/io/swagger/parser/test/V2ConverterTest.java

@@ -74,6 +74,7 @@ public class V2ConverterTest {
     private static final String ISSUE_672_JSON = "issue-672.json";
     private static final String ISSUE_673_YAML = "issue-673.yaml";
     private static final String ISSUE_676_JSON = "issue-676.json";
+    private static final String ISSUE_708_YAML = "issue-708.yaml";
 
     private static final String API_BATCH_PATH = "/api/batch/";
     private static final String PETS_PATH = "/pets";
@@ -600,7 +601,17 @@ public void testIssue673() throws Exception {
         assertEquals(2, schema.getMinLength().intValue());
         assertEquals(7, schema.getMaxLength().intValue());
         assertEquals("aaa", schema.getPattern());
+    }
 
+    @Test(description = "OpenAPI v2 converter - Migrate minLength, maxLength and pattern of String property")
+    public void testIssue708() throws Exception {
+        final OpenAPI oas = getConvertedOpenAPIFromJsonFile(ISSUE_708_YAML);
+        assertNotNull(oas);
+        Schema schema = oas.getComponents().getSchemas().get("SomeObj");
+        assertNotNull(schema);
+        assertEquals(schema.getMinLength(), Integer.valueOf(1));
+        assertEquals(schema.getMaxLength(), Integer.valueOf(3));
+        assertEquals(schema.getPattern(), "^[0-9]+$");
     }
 
     private OpenAPI getConvertedOpenAPIFromJsonFile(String file) throws IOException, URISyntaxException {

modules/swagger-parser-v2-converter/src/test/resources/issue-708.yaml

@@ -0,0 +1,37 @@
+swagger: '2.0'
+info:
+  description: 'Test'
+  version: 1.0.0
+  title: OpenAPI Test
+  license:
+    name: Apache-2.0
+    url: 'http://www.apache.org/licenses/LICENSE-2.0.html'
+host: petstore.swagger.io
+basePath: /v2
+schemes:
+  - http
+paths:
+  /ping:
+    post:
+      summary: test
+      description: 'test it'
+      operationId: pingOp
+      consumes:
+        - application/json
+      produces:
+        - application/json
+      parameters:
+        - in: body
+          name: body
+          required: true
+          schema:
+            $ref: '#/definitions/SomeObj'
+      responses:
+        '200':
+          description: OK
+definitions:
+  SomeObj:
+    type: string
+    minLength: 1
+    maxLength: 3
+    pattern: ^[0-9]+$