Merge pull request #153 from ba-st/conditional-caching-directive

Conditional caching directive
ba-st · Apr 18, 2022 · 683620f · 683620f
2 parents 13974c3 + 8f59430
commit 683620f
Show file tree

Hide file tree

Showing 4 changed files with 92 additions and 15 deletions.
diff --git a/docs/reference/Controllers.md b/docs/reference/Controllers.md
@@ -263,11 +263,15 @@ Both `private` and `no-cache` directives can specify a list of fields that
 restrict them using `bePrivateRestrictedTo: aFieldNameCollection` and
 `doNotCacheRestrictedTo: aFieldNameCollection` respectively.
 
+Additionally, if you may have different caching directive depending on the
+response, you can add a condition before configuring the builder.
+
 For specific examples on all the different options offered by Stargate, check the
 example classes and their respective tests:
 
-- `PetsRESTfulController` offers `/pets` as a _public_ resource for _4 hours_,
-  which _can't be transformed_, and _must be revalidated_ once stale.
+- `PetsRESTfulController` offers `/pets` as a _public_ resource for _4 hours_, but
+  when using a specific content-type it _can't be transformed_, and
+  _must be revalidated_ once stale.
 - `PetOrdersRESTfulController` offers `/orders` as a _public_ resource for
   _1 minute_, using both the `expires` header and the `max-age` directive.
 - `PetOrdersRESTfulController` offers `/orders/<id>/comments`, indicating

diff --git a/source/Stargate-Examples-Tests/PetsRESTfulControllerTest.class.st b/source/Stargate-Examples-Tests/PetsRESTfulControllerTest.class.st
@@ -365,7 +365,7 @@ PetsRESTfulControllerTest >> testGetPetSummaryJustCreated [
 		equals: resourceController petSummaryVersion1dot0dot0MediaType;
 		assert: response entityTag equals: '"1323cdfb8bb0f9011fbd480c5a87c17d05883214"' asEntityTag.
 	self assertExpiresHeaderFor: response with: 4 hours.
-	self assertCachingDirectivesFor: response with: #( 'public' 'no-transform' 'must-revalidate' ).
+	self assertCachingDirectivesFor: response with: #('public').
 
 	self withJsonFromContentsIn: response do: [ :json | 
 		self
@@ -391,7 +391,7 @@ PetsRESTfulControllerTest >> testGetPets [
 		assert: response contentType asMediaType
 			equals: resourceController petSummaryVersion1dot0dot0MediaType.
 	self assertExpiresHeaderFor: response with: 4 hours.
-	self assertCachingDirectivesFor: response with: #('public' 'no-transform' 'must-revalidate').
+	self assertCachingDirectivesFor: response with: #('public').
 
 	self
 		withJsonFromContentsIn: response
@@ -423,7 +423,7 @@ PetsRESTfulControllerTest >> testGetPetsNotEmpty [
 		assert: response contentType asMediaType
 			equals: resourceController petSummaryVersion1dot0dot0MediaType.
 	self assertExpiresHeaderFor: response with: 4 hours.
-	self assertCachingDirectivesFor: response with: #('public' 'no-transform' 'must-revalidate').
+	self assertCachingDirectivesFor: response with: #('public').
 
 	self
 		withJsonFromContentsIn: response
@@ -441,6 +441,45 @@ PetsRESTfulControllerTest >> testGetPetsNotEmpty [
 			]
 ]
 
+{ #category : #'tests - get collection' }
+PetsRESTfulControllerTest >> testGetPetsNotEmptyAcceptingCompleteMediaType [
+
+	| response |
+
+	resourceController
+		createPetBasedOn: ( self requestToCreatePetFrom: '{"name":"Firulais","type":"dog"}' )
+		within: self newHttpRequestContext.
+
+	self assert: petRepository findAll notEmpty.
+
+	response := resourceController
+		getPetsBasedOn: ( self requestToGetPetsAccepting: resourceController petVersion1dot0dot0MediaType )
+		within: self newHttpRequestContext.
+
+	self
+		assert: response isSuccess;
+		assert: response status equals: 200;
+		assert: response contentType asMediaType 
+			equals: resourceController petVersion1dot0dot0MediaType.
+	self assertExpiresHeaderFor: response with: 4 hours.
+	self assertCachingDirectivesFor: response with: #('public' 'no-transform' 'must-revalidate').
+
+	self
+		withJsonFromContentsIn: response
+			do: [ :json | self assertUrl: json selfLocation equals: 'https://pets.example.com/pets' ];
+		withJsonFromItemsIn: response
+			do: [ :items | 
+			self
+				withTheOnlyOneIn: items
+				do: [ :dogSummary | 
+					self
+						assert: dogSummary name equals: 'Firulais';
+						assertUrl: dogSummary selfLocation equals: 'https://pets.example.com/pets/1';
+						assert: dogSummary type equals: 'dog'.
+					]
+			]
+]
+
 { #category : #'tests - get collection' }
 PetsRESTfulControllerTest >> testGetPetsWithPagination [
 

diff --git a/source/Stargate-Examples/PetsRESTfulController.class.st b/source/Stargate-Examples/PetsRESTfulController.class.st
@@ -203,10 +203,18 @@ PetsRESTfulController >> initializeRequestHandler [
 			];
 		directCachingWith: [ :caching | 
 			caching
-				expireIn: 4 hours;
-				bePublic;
-				doNotTransform;
-				mustRevalidate
+				when: [ :response | response contentType = self petVersion1dot0dot0MediaType ]
+					apply: [ caching
+						expireIn: 4 hours;
+						bePublic;
+						doNotTransform;
+						mustRevalidate
+					];
+				when: [ :response | response contentType = self petSummaryVersion1dot0dot0MediaType ]
+					apply: [ caching
+						expireIn: 4 hours;
+						bePublic
+					]
 			];
 		build
 ]

diff --git a/source/Stargate-Model/CachingDirectivesBuilder.class.st b/source/Stargate-Model/CachingDirectivesBuilder.class.st
@@ -5,15 +5,20 @@ Class {
 	#name : #CachingDirectivesBuilder,
 	#superclass : #Object,
 	#instVars : [
-		'directives'
+		'directives',
+		'currentCondition'
 	],
 	#category : #'Stargate-Model-Caching'
 }
 
 { #category : #private }
 CachingDirectivesBuilder >> addCacheControlNamed: aName [
 
-	directives add: [ :response :context | response addCachingDirective: aName ]
+	| condition |
+
+	condition := currentCondition.
+	directives
+		add: [ :response :context | ( condition value: response ) then: [ response addCachingDirective: aName ] ]
 ]
 
 { #category : #private }
@@ -28,6 +33,12 @@ CachingDirectivesBuilder >> addCacheControlNamed: aName withToken: aValue [
 	self addCacheControlNamed: ( '<1s>=<2p>' expandMacrosWith: aName with: aValue )
 ]
 
+{ #category : #private }
+CachingDirectivesBuilder >> alwaysApplyDirectives [
+
+	currentCondition := [ :response | true ]
+]
+
 { #category : #configuring }
 CachingDirectivesBuilder >> beAvailableFor: aDuration [
 
@@ -119,10 +130,15 @@ CachingDirectivesBuilder >> doNotTransform [
 
 { #category : #configuring }
 CachingDirectivesBuilder >> expireIn: aDuration [
+
+	| condition |
 
+	condition := currentCondition.
 	directives
-		add:
-			[ :response :context | response headers at: 'Expires' put: ( ZnUtils httpDate: DateAndTime now + aDuration ) ]
+		add: [ :response :context | 
+			( condition value: response )
+				then: [ response headers at: 'Expires' put: ( ZnUtils httpDate: DateAndTime now + aDuration ) ]
+			]
 ]
 
 { #category : #private }
@@ -141,9 +157,10 @@ CachingDirectivesBuilder >> fieldStringFor: aFieldNameCollection [
 
 { #category : #initialization }
 CachingDirectivesBuilder >> initialize [
-	
+
 	super initialize.
-	directives := OrderedCollection new
+	directives := OrderedCollection new.
+	self alwaysApplyDirectives
 ]
 
 { #category : #configuring }
@@ -160,6 +177,15 @@ CachingDirectivesBuilder >> requireRevalidation [
 		beStaleAfter: 0 seconds
 ]
 
+{ #category : #configuring }
+CachingDirectivesBuilder >> when: aResponseCondition apply: aDirectiveConfiguration [
+
+	[ currentCondition := aResponseCondition.
+	aDirectiveConfiguration cull: self
+	]
+		ensure: [ self alwaysApplyDirectives ]
+]
+
 { #category : #configuring }
 CachingDirectivesBuilder >> whenSharedBeStaleAfter: aDuration [