[ K6 Generator ] Support for extracting examples defined at parameter level of Swagger/OpenAPI specification, plus minor fixes

modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/K6ClientCodegen.java

@@ -16,28 +16,60 @@
 
 package org.openapitools.codegen.languages;
 
+import static org.openapitools.codegen.utils.StringUtils.camelize;
+import static org.openapitools.codegen.utils.StringUtils.dashize;
+import static org.openapitools.codegen.utils.StringUtils.underscore;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.Writer;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+import java.util.Objects;
+import java.util.Set;
+import java.util.TreeSet;
+import java.util.stream.Collectors;
+
+import javax.annotation.Nullable;
+
+import org.apache.commons.lang3.StringEscapeUtils;
+import org.apache.commons.lang3.StringUtils;
+import org.openapitools.codegen.CodegenConfig;
+import org.openapitools.codegen.CodegenConstants;
+import org.openapitools.codegen.CodegenModel;
+import org.openapitools.codegen.CodegenParameter;
+import org.openapitools.codegen.CodegenProperty;
+import org.openapitools.codegen.CodegenResponse;
+import org.openapitools.codegen.CodegenType;
+import org.openapitools.codegen.DefaultCodegen;
+import org.openapitools.codegen.SupportingFile;
+import org.openapitools.codegen.meta.GeneratorMetadata;
+import org.openapitools.codegen.meta.Stability;
+import org.openapitools.codegen.utils.ModelUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import com.google.common.collect.ImmutableMap.Builder;
+import com.samskivert.mustache.Mustache;
+import com.samskivert.mustache.Mustache.Lambda;
+import com.samskivert.mustache.Template;
+
 import io.swagger.v3.oas.models.OpenAPI;
 import io.swagger.v3.oas.models.Operation;
 import io.swagger.v3.oas.models.PathItem;
+import io.swagger.v3.oas.models.examples.Example;
 import io.swagger.v3.oas.models.info.Info;
 import io.swagger.v3.oas.models.info.License;
 import io.swagger.v3.oas.models.media.Schema;
 import io.swagger.v3.oas.models.parameters.RequestBody;
 import io.swagger.v3.oas.models.responses.ApiResponse;
 import io.swagger.v3.oas.models.servers.Server;
-import org.apache.commons.lang3.StringUtils;
-import org.openapitools.codegen.*;
-import org.openapitools.codegen.meta.GeneratorMetadata;
-import org.openapitools.codegen.meta.Stability;
-import org.openapitools.codegen.utils.ModelUtils;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import javax.annotation.Nullable;
-import java.io.File;
-import java.util.*;
-
-import static org.openapitools.codegen.utils.StringUtils.*;
 
 public class K6ClientCodegen extends DefaultCodegen implements CodegenConfig {
 
@@ -50,30 +82,98 @@ public K6ClientCodegen() {
 
     }
 
-    static class Parameter {
-        String key;
-        Object value;
-
-        public Parameter(String key, Object value) {
-            this.key = key;
-            this.value = value;
-        }
-
-        @Override
-        public int hashCode() {
-            return key.hashCode();
-        }
-
-        @Override
-        public boolean equals(Object obj) {
-            if (this == obj)
-                return true;
-            if (obj == null || getClass() != obj.getClass())
-                return false;
-            Parameter p = (Parameter) obj;
-            return key.equals(p.key) && value.equals(p.value);
-        }
-    }
+	static class Parameter {
+		String key;
+		Object value;
+		boolean hasExample;
+
+		public Parameter(String key, Object value) {
+			this.key = key;
+			this.value = value;
+		}
+
+		public Parameter(String key, Object exampleValue, boolean hasExample) {
+			this.key = key;
+			this.value = exampleValue;
+			this.hasExample = hasExample;
+		}
+
+		@Override
+		public int hashCode() {
+			return key.hashCode();
+		}
+
+		@Override
+		public boolean equals(Object obj) {
+			if (this == obj)
+				return true;
+			if (obj == null || getClass() != obj.getClass())
+				return false;
+			Parameter p = (Parameter) obj;
+			return key.equals(p.key) && value.equals(p.value) && hasExample == p.hasExample;
+		}
+	}
+
+	static class ParameterValueLambda implements Mustache.Lambda {
+		private static final String NO_EXAMPLE_PARAM_VALUE_PREFIX = "TODO_EDIT_THE_";
+
+		@Override
+		public void execute(Template.Fragment fragment, Writer writer) throws IOException {
+
+			// default used if no example is provided
+			String noExampleParamValue = String.join("",
+					quoteExample(
+							String.join("", NO_EXAMPLE_PARAM_VALUE_PREFIX, fragment.execute())), 
+					";",
+					" // specify value as there is no example value for this parameter in OpenAPI spec");
+
+			// param has example(s)
+			if (fragment.context() instanceof K6ClientCodegen.Parameter
+					&& ((K6ClientCodegen.Parameter) fragment.context()).hasExample) {
+
+				Object rawValue = ((K6ClientCodegen.Parameter) fragment.context()).value;
+
+				// handle as 'examples'
+				if (rawValue instanceof Map) {
+
+					@SuppressWarnings("unchecked")
+					Set<String> exampleValues = ((Map<String, Example>) rawValue).values().stream()
+							.map(x -> quoteExample(
+									StringEscapeUtils.escapeEcmaScript(
+											String.valueOf(x.getValue()))))
+							.collect(Collectors.toCollection(() -> new TreeSet<String>()));
+
+					if (!exampleValues.isEmpty()) {
+
+						writer.write(String.join("", 
+								Arrays.toString(exampleValues.toArray()), 
+								".shift();",
+								" // first element from list extracted from 'examples' field defined at the parameter level of OpenAPI spec"));
+
+					} else {
+						writer.write(noExampleParamValue);
+					}
+
+				// handle as (single) 'example'
+				} else {
+					writer.write(String.join("",
+							quoteExample(
+									StringEscapeUtils.escapeEcmaScript(
+											String.valueOf(
+									((K6ClientCodegen.Parameter) fragment.context()).value))),
+							";", 
+							" // extracted from 'example' field defined at the parameter level of OpenAPI spec"));
+				}
+
+			} else {
+				writer.write(noExampleParamValue);
+			}
+		}
+
+		private static String quoteExample(String exampleValue) {
+			return StringUtils.wrap(exampleValue, "'");
+		}
+	}
 
     static class HTTPBody {
         List<Parameter> parameters;
@@ -165,7 +265,7 @@ public HTTPRequestGroup(String groupName, Set<Parameter> variables, List<HTTPReq
         }
     }
 
-    private final Logger LOGGER = LoggerFactory.getLogger(JavascriptClientCodegen.class);
+    private final Logger LOGGER = LoggerFactory.getLogger(K6ClientCodegen.class);
 
     public static final String PROJECT_NAME = "projectName";
     public static final String MODULE_NAME = "moduleName";
@@ -345,8 +445,8 @@ public void preprocessOpenAPI(OpenAPI openAPI) {
                         }
                     }
 
-                    List<CodegenParameter> formParameteres = fromRequestBodyToFormParameters(requestBody, imports);
-                    for (CodegenParameter parameter : formParameteres) {
+                    List<CodegenParameter> formParameters = fromRequestBodyToFormParameters(requestBody, imports);
+                    for (CodegenParameter parameter : formParameters) {
                         String reference = "";
                         if (parameter.isModel) {
                             Schema nestedSchema = ModelUtils.getSchema(openAPI, parameter.baseType);
@@ -384,7 +484,23 @@ public void preprocessOpenAPI(OpenAPI openAPI) {
                             case "query":
                                 if (parameter.getIn().equals("query"))
                                     queryParams.add(new Parameter(parameter.getName(), getTemplateVariable(parameter.getName())));
-                                variables.add(new Parameter(toVarName(parameter.getName()), parameter.getName().toUpperCase(Locale.ROOT)));
+								if (!pathVariables.containsKey(path)) {
+									// use 'example' field defined at the parameter level of OpenAPI spec
+									if (Objects.nonNull(parameter.getExample())) {
+										variables.add(new Parameter(toVarName(parameter.getName()),
+												parameter.getExample(), true));
+
+									// use 'examples' field defined at the parameter level of OpenAPI spec
+									} else if (Objects.nonNull(parameter.getExamples())) {
+										variables.add(new Parameter(toVarName(parameter.getName()),
+												parameter.getExamples(), true));
+
+									// no example provided, generated script will contain placeholder value
+									} else {
+										variables.add(new Parameter(toVarName(parameter.getName()),
+												parameter.getName().toUpperCase(Locale.ROOT)));
+									}
+								}
                                 break;
                             default:
                                 break;
@@ -432,7 +548,6 @@ public void preprocessOpenAPI(OpenAPI openAPI) {
         }
     }
 
-    //
     private String generateNestedModelTemplate(CodegenModel model) {
         StringBuilder reference = new StringBuilder();
         int modelEntrySetSize = model.getAllVars().size();
@@ -629,4 +744,9 @@ private static String getAccept(OpenAPI openAPI, Operation operation) {
 
         return accepts;
     }
+
+	@Override
+	protected Builder<String, Lambda> addMustacheLambdas() {
+		return super.addMustacheLambdas().put("handleParamValue", new ParameterValueLambda());
+	}
 }

modules/openapi-generator/src/main/resources/k6/README.mustache

@@ -4,6 +4,8 @@ The `script.js` file contains most of the Swagger/OpenAPI specification and you
 
 Global header variables are defined at the top of the file, like `api_key`. Each path in the specification is converted into a [group](https://docs.k6.io/docs/tags-and-groups) in k6 and each group contains all the request methods related to that path. Path and query parameters are extracted from the specification and put at the start of the group. The URL is constructed from the base URL plus path and query.
 
+If the Swagger/OpenAPI specification used as the input spec contains examples at parameter level, those will be extracted and utilized as parameter values. The `handleParamValue` custom Mustache lambda registered for use in the K6 `script.mustache` template handles the conditional checks, formatting, and outputting of parameter values. If a given parameter has value specified – either in `example` or `examples` field, defined at the parameter level – that value will be used. For list (`examples`), entire list will be output in the generated script and the first element from that list will be assigned as parameter value. If a given parameter does not have an example defined, a placeholder value with `TODO_EDIT_THE_` prefix will be generated for that parameter, and you will have to assign a value before you can run the script. In other words, you can now generate K6 test scripts which are ready to run, provided the Swagger/OpenAPI specification used as the input spec contains examples for all of the path/query parameters; see `modules/openapi-generator/src/test/resources/3_0/examples.yaml` for an example of such specification, and https://swagger.io/docs/specification/adding-examples/ for more information about adding examples.
+
 k6 specific parameters are in the [`params`](https://docs.k6.io/docs/params-k6http) object, and `body` contains the [request](https://docs.k6.io/docs/http-requests) body which is in the form of `identifier: type`, which the `type` should be substituted by a proper value. Then goes the request and the check.
 
 [Check](https://docs.k6.io/docs/checks) are like asserts but differ in that they don't halt execution, instead they just store the result of the check, pass or fail, and let the script execution continue.

modules/openapi-generator/src/main/resources/k6/script.mustache

@@ -16,7 +16,7 @@ export default function() {
     {{#requestGroups}}
     group("{{{groupName}}}", () => {
         {{#variables}}
-        let {{{key}}} = "TODO_EDIT_THE_{{{value}}}";
+        let {{{key}}} = {{#lambda.handleParamValue}}{{value}}{{/lambda.handleParamValue}}
         {{/variables}}
         {{#requests}}
         {{#-first}}

modules/openapi-generator/src/test/resources/3_0/examples.yaml

@@ -42,7 +42,7 @@ paths:
           in: query
           schema:
             type: string
-            example: 'example2 value'
+          example: 'example2 value'
       responses:
         '200':
           description: successful operation
@@ -61,7 +61,7 @@ paths:
           description: successful operation
   /example3/plural:
     get:
-      operationId: example3GetSingular
+      operationId: example3GetPlural
       parameters:
         - name: parameter
           in: query
@@ -92,7 +92,7 @@ paths:
           description: successful operation
   /example4/plural:
     post:
-      operationId: example4PostSingular
+      operationId: example4PostPlural
       requestBody:
         content:
           application/x-www-form-urlencoded:

samples/client/petstore/k6/.openapi-generator/VERSION

@@ -1 +1 @@
-5.0.0-SNAPSHOT
+5.2.0-SNAPSHOT

samples/client/petstore/k6/README.md

@@ -4,6 +4,8 @@ The `script.js` file contains most of the Swagger/OpenAPI specification and you
 
 Global header variables are defined at the top of the file, like `api_key`. Each path in the specification is converted into a [group](https://docs.k6.io/docs/tags-and-groups) in k6 and each group contains all the request methods related to that path. Path and query parameters are extracted from the specification and put at the start of the group. The URL is constructed from the base URL plus path and query.
 
+If the Swagger/OpenAPI specification used as the input spec contains examples at parameter level, those will be extracted and utilized as parameter values. The `handleParamValue` custom Mustache lambda registered for use in the K6 `script.mustache` template handles the conditional checks, formatting, and outputting of parameter values. If a given parameter has value specified – either in `example` or `examples` field, defined at the parameter level – that value will be used. For list (`examples`), entire list will be output in the generated script and the first element from that list will be assigned as parameter value. If a given parameter does not have an example defined, a placeholder value with `TODO_EDIT_THE_` prefix will be generated for that parameter, and you will have to assign a value before you can run the script. In other words, you can now generate K6 test scripts which are ready to run, provided the Swagger/OpenAPI specification used as the input spec contains examples for all of the path/query parameters; see `modules/openapi-generator/src/test/resources/3_0/examples.yaml` for an example of such specification, and https://swagger.io/docs/specification/adding-examples/ for more information about adding examples.
+
 k6 specific parameters are in the [`params`](https://docs.k6.io/docs/params-k6http) object, and `body` contains the [request](https://docs.k6.io/docs/http-requests) body which is in the form of `identifier: type`, which the `type` should be substituted by a proper value. Then goes the request and the check.
 
 [Check](https://docs.k6.io/docs/checks) are like asserts but differ in that they don't halt execution, instead they just store the result of the check, pass or fail, and let the script execution continue.

samples/client/petstore/k6/script.js

@@ -1,13 +1,13 @@
 /*
  * OpenAPI Petstore
- * This is a sample server Petstore server. For this sample, you can use the api key \"special-key\" to test the authorization filters
+ * This is a sample server Petstore server. For this sample, you can use the api key `special-key` to test the authorization filters.
  *
  * OpenAPI spec version: 1.0.0
  *
  * NOTE: This class is auto generated by OpenAPI Generator.
  * https://github.com/OpenAPITools/openapi-generator
  *
- * OpenAPI generator version: 5.0.0-SNAPSHOT
+ * OpenAPI generator version: 5.2.0-SNAPSHOT
  */
 
 
@@ -39,7 +39,7 @@ export default function() {
         sleep(SLEEP_DURATION);
     });
     group("/pet/findByStatus", () => {
-        let status = "TODO_EDIT_THE_STATUS";
+        let status = 'TODO_EDIT_THE_STATUS'; // specify value as there is no example value for this parameter in OpenAPI spec
         let url = BASE_URL + `/pet/findByStatus?status=${status}`;
         // Request No. 1
         let request = http.get(url);
@@ -49,7 +49,7 @@ export default function() {
         sleep(SLEEP_DURATION);
     });
     group("/pet/findByTags", () => {
-        let tags = "TODO_EDIT_THE_TAGS";
+        let tags = 'TODO_EDIT_THE_TAGS'; // specify value as there is no example value for this parameter in OpenAPI spec
         let url = BASE_URL + `/pet/findByTags?tags=${tags}`;
         // Request No. 1
         let request = http.get(url);
@@ -59,7 +59,7 @@ export default function() {
         sleep(SLEEP_DURATION);
     });
     group("/pet/{petId}", () => {
-        let petId = "TODO_EDIT_THE_PETID";
+        let petId = 'TODO_EDIT_THE_PETID'; // specify value as there is no example value for this parameter in OpenAPI spec
         let url = BASE_URL + `/pet/${petId}`;
         // Request No. 1
         let request = http.get(url);
@@ -81,7 +81,7 @@ export default function() {
         sleep(SLEEP_DURATION);
     });
     group("/pet/{petId}/uploadImage", () => {
-        let petId = "TODO_EDIT_THE_PETID";
+        let petId = 'TODO_EDIT_THE_PETID'; // specify value as there is no example value for this parameter in OpenAPI spec
         let url = BASE_URL + `/pet/${petId}/uploadImage`;
         // Request No. 1
         // TODO: edit the parameters of the request body.
@@ -115,7 +115,7 @@ export default function() {
         sleep(SLEEP_DURATION);
     });
     group("/store/order/{orderId}", () => {
-        let orderId = "TODO_EDIT_THE_ORDERID";
+        let orderId = 'TODO_EDIT_THE_ORDERID'; // specify value as there is no example value for this parameter in OpenAPI spec
         let url = BASE_URL + `/store/order/${orderId}`;
         // Request No. 1
         let request = http.get(url);
@@ -161,8 +161,8 @@ export default function() {
         sleep(SLEEP_DURATION);
     });
     group("/user/login", () => {
-        let password = "TODO_EDIT_THE_PASSWORD";
-        let username = "TODO_EDIT_THE_USERNAME";
+        let password = 'TODO_EDIT_THE_PASSWORD'; // specify value as there is no example value for this parameter in OpenAPI spec
+        let username = 'TODO_EDIT_THE_USERNAME'; // specify value as there is no example value for this parameter in OpenAPI spec
         let url = BASE_URL + `/user/login?username=${username}&password=${password}`;
         // Request No. 1
         let request = http.get(url);
@@ -181,7 +181,7 @@ export default function() {
         sleep(SLEEP_DURATION);
     });
     group("/user/{username}", () => {
-        let username = "TODO_EDIT_THE_USERNAME";
+        let username = 'TODO_EDIT_THE_USERNAME'; // specify value as there is no example value for this parameter in OpenAPI spec
         let url = BASE_URL + `/user/${username}`;
         // Request No. 1
         let request = http.get(url);