go: Fix missing imports for optional body params.

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

@@ -115,6 +115,15 @@ public boolean getHasBodyParam() {
         return nonEmpty(bodyParams);
     }
 
+    /**
+     * Check if there's at least one optional body parameter
+     *
+     * @return true if optional body parameter exists, false otherwise
+     */
+    public boolean getHasOptionalBodyParam() {
+        return nonEmpty(bodyParams) && nonEmpty(optionalParams) && bodyParams.stream().anyMatch(optionalParams::contains);
+    }
+
     /**
      * Check if there's at least one query parameter
      *

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

@@ -410,6 +410,7 @@ public OperationsMap postProcessOperationsWithModels(OperationsMap objs, List<Mo
     private void addConditionalImportInformation(OperationsMap operations) {
         boolean hasPathParams = false;
         boolean hasBodyParams = false;
+        boolean hasOptionalBodyParams = false;
 
         for (CodegenOperation op : operations.getOperations().getOperation()) {
             if (op.getHasPathParams()) {
@@ -418,10 +419,14 @@ private void addConditionalImportInformation(OperationsMap operations) {
             if (op.getHasBodyParam()) {
                 hasBodyParams = true;
             }
+            if (op.getHasOptionalBodyParam()) {
+                hasOptionalBodyParams = true;
+            }
         }
 
         additionalProperties.put("hasPathParams", hasPathParams);
         additionalProperties.put("hasBodyParams", hasBodyParams);
+        additionalProperties.put("hasOptionalBodyParams", hasOptionalBodyParams);
     }
 
 

modules/openapi-generator/src/main/resources/go-server/controller-api.mustache

@@ -6,12 +6,10 @@ import (
 	{{#hasBodyParams}}
 	"encoding/json"
 	{{/hasBodyParams}}
-	{{#isBodyParam}}
-	    {{^required}}
+	{{#hasOptionalBodyParams}}
 	"errors"
 	"io"
-	    {{/required}}
-	{{/isBodyParam}}
+	{{/hasOptionalBodyParams}}
 	"net/http"
 	"strings"
 {{#imports}}	"{{import}}"