From 65fc1019ad1921f2a2e1ad96993892eebf650da2 Mon Sep 17 00:00:00 2001
From: Mattias Reichel <mattias.reichel@gmail.com>
Date: Tue, 7 Nov 2023 15:15:44 +0100
Subject: [PATCH] Add method to cancel Inertia processing. Useful in
 controllers if you want to respond with a http response without the Inertia
 headers.

---
 .../plugin/inertia/InertiaInterceptor.groovy  |  4 +---
 .../grails/plugin/inertia/Inertia.groovy      |  9 +++++++++
 .../grails/plugin/inertia/InertiaTrait.groovy |  8 ++++++++
 .../inertia/InertiaInterceptorSpec.groovy     | 20 +++++++++++++++++++
 4 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/grails-app/controllers/grails/plugin/inertia/InertiaInterceptor.groovy b/grails-app/controllers/grails/plugin/inertia/InertiaInterceptor.groovy
index df7792a..0b3aab1 100644
--- a/grails-app/controllers/grails/plugin/inertia/InertiaInterceptor.groovy
+++ b/grails-app/controllers/grails/plugin/inertia/InertiaInterceptor.groovy
@@ -23,7 +23,6 @@ import groovy.json.JsonSlurper
 import groovy.transform.CompileStatic
 import io.micronaut.http.HttpStatus
 
-import static Inertia.INERTIA_ATTRIBUTE_CANCEL_INERTIA
 import static Inertia.INERTIA_ATTRIBUTE_MANIFEST
 import static Inertia.INERTIA_ATTRIBUTE_VERSION
 import static Inertia.INERTIA_HEADER
@@ -64,7 +63,7 @@ class InertiaInterceptor implements GrailsConfigurationAware {
 
     boolean after() {
 
-        if (inertiaResponseCanceled) return true
+        if (Inertia.isCanceled) return true
 
         setContentType()
         setHeaders()
@@ -117,7 +116,6 @@ class InertiaInterceptor implements GrailsConfigurationAware {
     boolean getMethodNotAllowedShouldBePrevented() { isInertiaRequest && response.status == HttpStatus.FOUND.code && request.method in ['PUT', 'PATCH', 'DELETE'] }
     boolean getIsInertiaHtmlView() { modelAndView?.viewName == INERTIA_VIEW_HTML }
     boolean getIsInertiaRequest() { request.getHeader(INERTIA_HEADER) == 'true' }
-    boolean isInertiaResponseCanceled() { request.getAttribute(INERTIA_ATTRIBUTE_CANCEL_INERTIA) }
     boolean getIsAssetsCurrent() {
         def currentVersion = request.getAttribute(INERTIA_ATTRIBUTE_VERSION) as String
         def requestedVersion = request.getHeader(INERTIA_HEADER_VERSION) as String
diff --git a/src/main/groovy/grails/plugin/inertia/Inertia.groovy b/src/main/groovy/grails/plugin/inertia/Inertia.groovy
index 6fb2b6d..6378ca0 100644
--- a/src/main/groovy/grails/plugin/inertia/Inertia.groovy
+++ b/src/main/groovy/grails/plugin/inertia/Inertia.groovy
@@ -76,6 +76,15 @@ class Inertia {
         response.status = SC_CONFLICT
     }
 
+    @SuppressWarnings('unused')
+    static void cancel() {
+        request.setAttribute INERTIA_ATTRIBUTE_CANCEL_INERTIA, true
+    }
+
+    static boolean getIsCanceled() {
+        request.getAttribute INERTIA_ATTRIBUTE_CANCEL_INERTIA
+    }
+
     private static ModelAndView renderInternal(String component, Map props, Map viewData) {
         isInertiaRequest ?
             renderJson(component, props) :
diff --git a/src/main/groovy/grails/plugin/inertia/InertiaTrait.groovy b/src/main/groovy/grails/plugin/inertia/InertiaTrait.groovy
index 9103814..37c5a4a 100644
--- a/src/main/groovy/grails/plugin/inertia/InertiaTrait.groovy
+++ b/src/main/groovy/grails/plugin/inertia/InertiaTrait.groovy
@@ -58,4 +58,12 @@ trait InertiaTrait {
     void setInertiaSharedData(Map sharedData) {
         Inertia.sharedData = sharedData
     }
+
+    void cancelInertia() {
+        Inertia.cancel()
+    }
+
+    boolean isInertiaCanceled() {
+        Inertia.isCanceled
+    }
 }
\ No newline at end of file
diff --git a/src/test/groovy/grails/plugin/inertia/InertiaInterceptorSpec.groovy b/src/test/groovy/grails/plugin/inertia/InertiaInterceptorSpec.groovy
index fc9a5dd..37bbf57 100644
--- a/src/test/groovy/grails/plugin/inertia/InertiaInterceptorSpec.groovy
+++ b/src/test/groovy/grails/plugin/inertia/InertiaInterceptorSpec.groovy
@@ -106,6 +106,21 @@ class InertiaInterceptorSpec extends Specification implements InterceptorUnitTes
         ! response.containsHeader('X-Inertia')
         ! ('X-Inertia' in response.getHeaders('Vary'))
     }
+
+    def 'canceling Inertia request with Inertia.cancel() works'() {
+        given: 'a controller'
+        def controller = (TestController) mockController(TestController)
+
+        when: 'a request for json is processed'
+        request.addHeader 'X-Inertia', true
+        request.addHeader 'X-Inertia-Version', '0'
+        withInterceptors(controller: 'test', httpMethod: 'GET') { controller.cancelInertiaAction() }
+        interceptor.after()
+
+        then: 'no inertia response headers are set'
+        ! response.containsHeader('X-Inertia')
+        ! ('X-Inertia' in response.getHeaders('Vary'))
+    }
 }
 
 @Controller
@@ -116,6 +131,11 @@ class TestController {
         renderInertia 'index', [hello: 'world']
     }
 
+    def cancelInertiaAction() {
+        Inertia.cancel()
+        render 'cancelInertiaAction'
+    }
+
     def testing() {
         renderInertia 'testing'
     }