[R][client] Make enum parameters with required: false optional to request arguments (#19654)

* ODM-11697: Adding null check in R-api

* bin/generate-samples.sh executed

---------

Co-authored-by: Kunitsyn Oleg <114428801+genestack-okunitsyn@users.noreply.github.com>

modules/openapi-generator/src/main/resources/r/api.mustache

@@ -324,7 +324,7 @@
         {{#items}}
         {{#isEnum}}
         # validate enum values
-        if (!(query_item %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
+        if (!is.null(query_item) && !(query_item %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
           {{#useDefaultExceptionHandling}}
           stop("Invalid value for {{{paramName}}} when calling {{classname}}${{operationId}}. Must be {{_enum}}.")
           {{/useDefaultExceptionHandling}}
@@ -346,7 +346,7 @@
       {{#isEnum}}
       # validate enum values
       for (query_item in `{{{paramName}}}`) {
-        if (!(query_item %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
+        if (!is.null(query_item) && !(query_item %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
           {{#useDefaultExceptionHandling}}
           stop("Invalid value for {{{paramName}}} when calling {{classname}}${{operationId}}. Must be {{_enum}}.")
           {{/useDefaultExceptionHandling}}
@@ -370,7 +370,7 @@
         {{#items}}
         {{#isEnum}}
         # validate enum values
-        if (!(query_item %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
+        if (!is.null(query_item) && !(query_item %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
           {{#useDefaultExceptionHandling}}
           stop("Invalid value for {{{paramName}}} when calling {{classname}}${{operationId}}. Must be {{_enum}}.")
           {{/useDefaultExceptionHandling}}
@@ -392,7 +392,7 @@
       {{#isEnum}}
       # validate enum values
       for (query_item in `{{{paramName}}}`) {
-        if (!(query_item %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
+        if (!is.null(query_item) && !(query_item %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
           {{#useDefaultExceptionHandling}}
           stop("Invalid value for {{{paramName}}} when calling {{classname}}${{operationId}}. Must be {{_enum}}.")
           {{/useDefaultExceptionHandling}}
@@ -412,7 +412,7 @@
       {{/isArray}}
       {{^isArray}}
       {{#isEnum}}
-      if (!(`{{paramName}}` %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
+      if (!is.null(`{{paramName}}`) && !(`{{paramName}}` %in% c({{#_enum}}"{{{.}}}"{{^-last}}, {{/-last}}{{/_enum}}))) {
         {{#useDefaultExceptionHandling}}
         stop("Invalid value for {{{paramName}}} when calling {{classname}}${{operationId}}. Must be {{_enum}}.")
         {{/useDefaultExceptionHandling}}

modules/openapi-generator/src/test/java/org/openapitools/codegen/r/RClientCodegenTest.java

@@ -17,11 +17,21 @@
 
 package org.openapitools.codegen.r;
 
+import io.swagger.v3.oas.models.OpenAPI;
+import org.openapitools.codegen.ClientOptInput;
 import org.openapitools.codegen.CodegenConstants;
+import org.openapitools.codegen.DefaultGenerator;
+import org.openapitools.codegen.TestUtils;
 import org.openapitools.codegen.languages.RClientCodegen;
 import org.testng.Assert;
 import org.testng.annotations.Test;
 
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.regex.Pattern;
+
 public class RClientCodegenTest {
 
     @Test
@@ -53,4 +63,35 @@ public class RClientCodegenTest {
         Assert.assertEquals(codegen.isHideGenerationTimestamp(), false);
     }
 
+    @Test
+    public void testNullCheckOnEnumValues() throws IOException {
+        File output = Files.createTempDirectory("test").toFile().getCanonicalFile();
+        output.deleteOnExit();
+        final DefaultGenerator defaultGenerator = new DefaultGenerator();
+
+        RClientCodegen rClientCodegen = new RClientCodegen();
+        rClientCodegen.setOutputDir(output.getAbsolutePath());
+
+        final OpenAPI openAPI = TestUtils.parseFlattenSpec("src/test/resources/bugs/issue_18016.yaml");
+        final ClientOptInput clientOptInput = new ClientOptInput();
+        clientOptInput.openAPI(openAPI);
+        clientOptInput.config(rClientCodegen);
+        defaultGenerator.opts(clientOptInput);
+
+        var petsApi = defaultGenerator.generate().stream()
+                          .filter(file -> "pets_api.R".equals(file.getName())).findFirst();
+        if (petsApi.isEmpty()) {
+            Assert.fail("`pets_api.R` have not been generated");
+        }
+        var isIfCondition = Pattern.compile("^\\s*(?!<#)\\s*if.*\\s%in%\\s.*").asPredicate();
+        var containsNullCheck = Pattern.compile("![(\\s]*is\\.null").asPredicate();
+        var hit = false;
+        for (var line: Files.readAllLines(Paths.get(petsApi.get().getAbsolutePath()))) {
+            if (isIfCondition.test(line)) {
+                hit = true;
+                Assert.assertTrue(containsNullCheck.test(line), "Null check is missing in line: " + line);
+            }
+        }
+        Assert.assertTrue(hit, "No if statement for enum found");
+    }
 }

modules/openapi-generator/src/test/resources/bugs/issue_18016.yaml

@@ -0,0 +1,27 @@
+openapi: "3.0.0"
+info:
+  version: 1.0.0
+  description: Specification to generate null check for enums in R client
+  title: RClientNullCheck
+paths:
+  /exists:
+    get:
+      tags:
+        - pets
+      parameters:
+        - name: type
+          in: query
+          description: Type of pet
+          required: false
+          schema:
+            enum:
+              - cat
+              - dog
+            type: string
+      responses:
+        '200':
+          description: OK
+          content:
+            application/json:
+              schema:
+                type: boolean

samples/client/echo_api/r/R/query_api.R

@@ -223,7 +223,7 @@ QueryApi <- R6::R6Class(
 
 
 
-      if (!(`enum_nonref_string_query` %in% c("success", "failure", "unclassified"))) {
+      if (!is.null(`enum_nonref_string_query`) && !(`enum_nonref_string_query` %in% c("success", "failure", "unclassified"))) {
         stop("Invalid value for enum_nonref_string_query when calling QueryApi$TestEnumRefString. Must be [success, failure, unclassified].")
       }
       query_params[["enum_nonref_string_query"]] <- `enum_nonref_string_query`

samples/client/petstore/R-httr2-wrapper/R/pet_api.R

@@ -664,7 +664,7 @@ PetApi <- R6::R6Class(
       # explore
       for (query_item in `status`) {
         # validate enum values
-        if (!(query_item %in% c("available", "pending", "sold"))) {
+        if (!is.null(query_item) && !(query_item %in% c("available", "pending", "sold"))) {
           rlang::abort(message = "Invalid value for `status` when calling PetApi$find_pets_by_status. Must be [available, pending, sold].",
                        .subclass = "ApiException",
                        ApiException = ApiException$new(status = 0,

samples/client/petstore/R-httr2/R/pet_api.R

@@ -664,7 +664,7 @@ PetApi <- R6::R6Class(
       # explore
       for (query_item in `status`) {
         # validate enum values
-        if (!(query_item %in% c("available", "pending", "sold"))) {
+        if (!is.null(query_item) && !(query_item %in% c("available", "pending", "sold"))) {
           rlang::abort(message = "Invalid value for `status` when calling PetApi$find_pets_by_status. Must be [available, pending, sold].",
                        .subclass = "ApiException",
                        ApiException = ApiException$new(status = 0,

samples/client/petstore/R/R/pet_api.R

@@ -664,7 +664,7 @@ PetApi <- R6::R6Class(
       # explore
       for (query_item in `status`) {
         # validate enum values
-        if (!(query_item %in% c("available", "pending", "sold"))) {
+        if (!is.null(query_item) && !(query_item %in% c("available", "pending", "sold"))) {
           rlang::abort(message = "Invalid value for `status` when calling PetApi$FindPetsByStatus. Must be [available, pending, sold].",
                        .subclass = "ApiException",
                        ApiException = ApiException$new(status = 0,