Add Providers to Blueprint
Providers are a new concept for Blueprint, based on providers in Bazel:
https://docs.bazel.build/versions/master/skylark/rules.html#providers
Providers aim to simplify the interaction between modules by replacing
type asserting to arbitrary interfaces with requesting optional data
objects from modules. This will also move Blueprint closer to supporting
incremental analysis by serializing the providers and only rerunning
the analysis phase on modules whose inputs have changed.
Change-Id: I39f5f78b372412a7dbf151ceccb3f917f6c874bf
diff --git a/singleton_ctx.go b/singleton_ctx.go
index 3c0a24c..a4e7153 100644
--- a/singleton_ctx.go
+++ b/singleton_ctx.go
@@ -47,6 +47,16 @@
// BlueprintFile returns the path of the Blueprint file that defined the given module.
BlueprintFile(module Module) string
+ // ModuleProvider returns the value, if any, for the provider for a module. If the value for the
+ // provider was not set it returns the zero value of the type of the provider, which means the
+ // return value can always be type-asserted to the type of the provider. The return value should
+ // always be considered read-only. It panics if called before the appropriate mutator or
+ // GenerateBuildActions pass for the provider on the module.
+ ModuleProvider(module Module, provider ProviderKey) interface{}
+
+ // ModuleHasProvider returns true if the provider for the given module has been set.
+ ModuleHasProvider(m Module, provider ProviderKey) bool
+
// ModuleErrorf reports an error at the line number of the module type in the module definition.
ModuleErrorf(module Module, format string, args ...interface{})
@@ -188,6 +198,15 @@
return s.context.ModuleType(logicModule)
}
+func (s *singletonContext) ModuleProvider(logicModule Module, provider ProviderKey) interface{} {
+ return s.context.ModuleProvider(logicModule, provider)
+}
+
+// ModuleHasProvider returns true if the provider for the given module has been set.
+func (s *singletonContext) ModuleHasProvider(logicModule Module, provider ProviderKey) bool {
+ return s.context.ModuleHasProvider(logicModule, provider)
+}
+
func (s *singletonContext) BlueprintFile(logicModule Module) string {
return s.context.BlueprintFile(logicModule)
}