Fix multipart fields in vertx

[wing328]

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---

Summary by cubic

Fix multipart form file handling in Vert.x server generator to select uploads by field name, preventing wrong file mapping when multiple files or fields are present. Updated sample handlers and bumped spring-web in a sample.

• Bug Fixes

  • In JavaVertXWebServer/formParams.mustache, file params now filter routingContext.fileUploads() by the form field name and return 400 when required and missing.
  • Updated Vert.x sample PetApiHandler implementations to use the same logic.

• Dependencies

  • Bump spring-web to 7.0.8 in samples/client/petstore/java/resttemplate-springBoot4-jackson3/pom.xml.

^{Written for commit 0e71892. Summary will update on new commits.}

[cubic-dev-ai]

3 issues found across 4 files

Prompt for AI agents (unresolved issues)

Check if these issues are valid — if so, understand the root cause of each and fix them. If appropriate, use sub-agents to investigate and fix each issue separately.


<file name="modules/openapi-generator/src/main/resources/JavaVertXWebServer/formParams.mustache">

<violation number="1" location="modules/openapi-generator/src/main/resources/JavaVertXWebServer/formParams.mustache:11">
P3: Optional file parameters generate an empty `if` block; wrap the entire null check in `{{#required}}` so optional uploads emit no dead branch.</violation>

<violation number="2" location="modules/openapi-generator/src/main/resources/JavaVertXWebServer/formParams.mustache:11">
P2: This template change breaks the existing unit test for this generator. `JavaVertXWebServerCodegenTest.itShouldCheckFileUploadEmptiness` still asserts the old output strings `if (routingContext.fileUploads().isEmpty()) {`, `} else {`, and `_file = routingContext.fileUploads().iterator().next();`, but the template no longer emits any of them, so the test will fail and the module build/CI will go red. Please update the test assertions (and ideally add coverage for the new field-name filter plus the 400-on-missing-required-file behavior) alongside this template change.</violation>
</file>

<file name="samples/server/petstore/java-vertx-web/src/main/java/org/openapitools/vertxweb/server/api/PetApiHandler.java">

<violation number="1" location="samples/server/petstore/java-vertx-web/src/main/java/org/openapitools/vertxweb/server/api/PetApiHandler.java:219">
P3: The `if (_file == null) { }` block is empty dead code: when the multipart `file` field is optional (as in the petstore spec), the generated handler does nothing on a missing file and proceeds to call `api.uploadFile(petId, null)`. Wrap the null-check in the template's `{{#required}}` section so it is only emitted with the `fail(400); return;` body, avoiding a misleading no-op for optional uploads.</violation>
</file>

<sub>Reply with feedback, questions, or to request a fix.

Re-trigger cubic</sub>

[cubic-dev-ai]

P2: This template change breaks the existing unit test for this generator. JavaVertXWebServerCodegenTest.itShouldCheckFileUploadEmptiness still asserts the old output strings if (routingContext.fileUploads().isEmpty()) {, } else {, and _file = routingContext.fileUploads().iterator().next();, but the template no longer emits any of them, so the test will fail and the module build/CI will go red. Please update the test assertions (and ideally add coverage for the new field-name filter plus the 400-on-missing-required-file behavior) alongside this template change.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At modules/openapi-generator/src/main/resources/JavaVertXWebServer/formParams.mustache, line 11:

<comment>This template change breaks the existing unit test for this generator. `JavaVertXWebServerCodegenTest.itShouldCheckFileUploadEmptiness` still asserts the old output strings `if (routingContext.fileUploads().isEmpty()) {`, `} else {`, and `_file = routingContext.fileUploads().iterator().next();`, but the template no longer emits any of them, so the test will fail and the module build/CI will go red. Please update the test assertions (and ideally add coverage for the new field-name filter plus the 400-on-missing-required-file behavior) alongside this template change.</comment>

<file context>
@@ -4,14 +4,15 @@
+            .filter(upload -> "{{baseName}}".equals(upload.name()))
+            .findFirst()
+            .orElse(null);
+        if ({{paramName}} == null) {
 {{#required}}
             routingContext.fail(400);
</file context>

[cubic-dev-ai]

P3: Optional file parameters generate an empty if block; wrap the entire null check in {{#required}} so optional uploads emit no dead branch.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At modules/openapi-generator/src/main/resources/JavaVertXWebServer/formParams.mustache, line 11:

<comment>Optional file parameters generate an empty `if` block; wrap the entire null check in `{{#required}}` so optional uploads emit no dead branch.</comment>

<file context>
@@ -4,14 +4,15 @@
+            .filter(upload -> "{{baseName}}".equals(upload.name()))
+            .findFirst()
+            .orElse(null);
+        if ({{paramName}} == null) {
 {{#required}}
             routingContext.fail(400);
</file context>

Suggested change

	if ({{paramName}} == null) {
	{{#required}}
	routingContext.fail(400);
	return;
	{{/required}}
	} else {
	{{paramName}} = routingContext.fileUploads().iterator().next();
	}
	{{#required}}
	if ({{paramName}} == null) {
	routingContext.fail(400);
	return;
	}
	{{/required}}

[cubic-dev-ai]

P3: The if (_file == null) { } block is empty dead code: when the multipart file field is optional (as in the petstore spec), the generated handler does nothing on a missing file and proceeds to call api.uploadFile(petId, null). Wrap the null-check in the template's {{#required}} section so it is only emitted with the fail(400); return; body, avoiding a misleading no-op for optional uploads.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At samples/server/petstore/java-vertx-web/src/main/java/org/openapitools/vertxweb/server/api/PetApiHandler.java, line 219:

<comment>The `if (_file == null) { }` block is empty dead code: when the multipart `file` field is optional (as in the petstore spec), the generated handler does nothing on a missing file and proceeds to call `api.uploadFile(petId, null)`. Wrap the null-check in the template's `{{#required}}` section so it is only emitted with the `fail(400); return;` body, avoiding a misleading no-op for optional uploads.</comment>

<file context>
@@ -212,10 +212,11 @@ private void uploadFile(RoutingContext routingContext) {
+            .filter(upload -> "file".equals(upload.name()))
+            .findFirst()
+            .orElse(null);
+        if (_file == null) {
         }
 
</file context>