Add option to use http.Header.Set when setting headers in Go client

[wing328]

a follow up pr to #24766

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---

Summary by cubic

Adds a useHttpHeaderSet option to the Go client generator that changes how prepareRequest assigns headers. The new default preserves header-name casing from the API spec instead of canonicalizing; set useHttpHeaderSet=true to restore the previous http.Header.Set behavior.

Migration

• Existing generated clients that relied on canonicalized headers must regenerate with useHttpHeaderSet=true.

^{Written for commit c0146b6. Summary will update on new commits.}

[cubic-dev-ai]

2 issues found across 17 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="samples/openapi3/client/petstore/go/go-petstore/client.go">

<violation number="1" location="samples/openapi3/client/petstore/go/go-petstore/client.go:426">
P2: When HTTP signature auth signs `x-api-key`, this assignment stores that casing, but `SignRequest` indexes `X-Api-Key` and returns an error. Use a case-insensitive lookup there or preserve a canonical key for signing.</violation>
</file>

<file name="modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoClientCodegen.java">

<violation number="1" location="modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/GoClientCodegen.java:281">
P2: The new useHttpHeaderSet option has no test coverage. Every other Go generator option is exercised in GoClientOptionsTest via GoClientOptionsProvider, but this one is skipped, so a regression in wiring (e.g. the option not being parsed or written back) would pass the build silently. Add USE_HTTP_HEADER_SET to GoClientOptionsProvider, verify setUseHttpHeaderSet in GoClientOptionsTest, and add a test asserting the generated prepareRequest uses headers.Set when true and direct assignment when false.</violation>
</file>

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

Re-trigger cubic</sub>

[cubic-dev-ai]

P2: When HTTP signature auth signs x-api-key, this assignment stores that casing, but SignRequest indexes X-Api-Key and returns an error. Use a case-insensitive lookup there or preserve a canonical key for signing.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At samples/openapi3/client/petstore/go/go-petstore/client.go, line 426:

<comment>When HTTP signature auth signs `x-api-key`, this assignment stores that casing, but `SignRequest` indexes `X-Api-Key` and returns an error. Use a case-insensitive lookup there or preserve a canonical key for signing.</comment>

<file context>
@@ -423,7 +423,7 @@ func (c *APIClient) prepareRequest(
 		headers := http.Header{}
 		for h, v := range headerParams {
-			headers.Set(h, v)
+		    headers[h] = []string{v}
 		}
 		localVarRequest.Header = headers
</file context>

[cubic-dev-ai]

P2: The new useHttpHeaderSet option has no test coverage. Every other Go generator option is exercised in GoClientOptionsTest via GoClientOptionsProvider, but this one is skipped, so a regression in wiring (e.g. the option not being parsed or written back) would pass the build silently. Add USE_HTTP_HEADER_SET to GoClientOptionsProvider, verify setUseHttpHeaderSet in GoClientOptionsTest, and add a test asserting the generated prepareRequest uses headers.Set when true and direct assignment when false.

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/java/org/openapitools/codegen/languages/GoClientCodegen.java, line 281:

<comment>The new useHttpHeaderSet option has no test coverage. Every other Go generator option is exercised in GoClientOptionsTest via GoClientOptionsProvider, but this one is skipped, so a regression in wiring (e.g. the option not being parsed or written back) would pass the build silently. Add USE_HTTP_HEADER_SET to GoClientOptionsProvider, verify setUseHttpHeaderSet in GoClientOptionsTest, and add a test asserting the generated prepareRequest uses headers.Set when true and direct assignment when false.</comment>

<file context>
@@ -276,6 +278,11 @@ public void processOpts() {
             additionalProperties.put(USE_DEFAULT_VALUES_FOR_REQUIRED_VARS, useDefaultValuesForRequiredVars);
         }
 
+        if (additionalProperties.containsKey(USE_HTTP_HEADER_SET)) {
+            setUseHttpHeaderSet(Boolean.parseBoolean(additionalProperties.get(USE_HTTP_HEADER_SET).toString()));
+            additionalProperties.put(USE_HTTP_HEADER_SET, useHttpHeaderSet);
</file context>

[cubic-dev-ai]

1 issue found across 2 files (changes from recent commits).

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/test/java/org/openapitools/codegen/options/GoClientOptionsProvider.java">

<violation number="1" location="modules/openapi-generator/src/test/java/org/openapitools/codegen/options/GoClientOptionsProvider.java:73">
P3: The new `USE_HTTP_HEADER_SET` constant is never referenced in `createOptions()`, which hardcodes the literal "true" instead. The test asserts `setUseHttpHeaderSet(USE_HTTP_HEADER_SET)`, so if the constant value is ever changed the option map and the test silently diverge. Use `String.valueOf(USE_HTTP_HEADER_SET)` (or the key constant `GoClientCodegen.USE_HTTP_HEADER_SET`) to keep them in sync.</violation>
</file>

<sub>Tip: Review your code locally with the cubic CLI to iterate faster.

Re-trigger cubic</sub>

[cubic-dev-ai]

P3: The new USE_HTTP_HEADER_SET constant is never referenced in createOptions(), which hardcodes the literal "true" instead. The test asserts setUseHttpHeaderSet(USE_HTTP_HEADER_SET), so if the constant value is ever changed the option map and the test silently diverge. Use String.valueOf(USE_HTTP_HEADER_SET) (or the key constant GoClientCodegen.USE_HTTP_HEADER_SET) to keep them in sync.

Prompt for AI agents

Check if this issue is valid — if so, understand the root cause and fix it. At modules/openapi-generator/src/test/java/org/openapitools/codegen/options/GoClientOptionsProvider.java, line 73:

<comment>The new `USE_HTTP_HEADER_SET` constant is never referenced in `createOptions()`, which hardcodes the literal "true" instead. The test asserts `setUseHttpHeaderSet(USE_HTTP_HEADER_SET)`, so if the constant value is ever changed the option map and the test silently diverge. Use `String.valueOf(USE_HTTP_HEADER_SET)` (or the key constant `GoClientCodegen.USE_HTTP_HEADER_SET`) to keep them in sync.</comment>

<file context>
@@ -68,6 +70,7 @@ public Map<String, String> createOptions() {
                 .put("structPrefix", "true")
                 .put(CodegenConstants.USE_DEFAULT_VALUES_FOR_REQUIRED_VARS, "true")
                 .put(CodegenConstants.ENUM_UNKNOWN_DEFAULT_CASE, ENUM_UNKNOWN_DEFAULT_CASE_VALUE)
+                .put("useHttpHeaderSet", "true")
                 .build();
     }
</file context>

Suggested change

	.put("useHttpHeaderSet", "true")
	.put("useHttpHeaderSet", String.valueOf(USE_HTTP_HEADER_SET))