Address PR comments

Author: erm-g

security/advancedtls/crl.go

@@ -116,8 +116,8 @@ func NewCRL(b []byte) (*CRL, error) {
 	return crlExt, nil
 }
 
-// ReadCRLFile reads a file from the provided path, and returns constructed
-// from it.
+// ReadCRLFile reads a file from the provided path, and returns constructed CRL
+// struct from it.
 func ReadCRLFile(path string) (*CRL, error) {
 	b, err := os.ReadFile(path)
 	if err != nil {

security/advancedtls/crl_provider.go

@@ -31,10 +31,13 @@ const defaultCRLRefreshDuration = 1 * time.Hour
 // CRLProvider is the interface to be implemented to enable custom CRL provider
 // behavior.
 //
-// The interface defines how the data is read, but doesn't prescribe a way
-// CRL are loaded and stored. Such implementations can be used in
-// RevocationConfig of advancedtls.ClientOptions and/or
-// advancedtls.ServerOptions .
+// The interface defines how gRPC gets CRLs from the provider during handshakes,
+// but doesn't prescribe a specific way to load and store CRLs. Such
+// implementations can be used in RevocationConfig of advancedtls.ClientOptions
+// and/or advancedtls.ServerOptions.
+// Please note that checking CRLs is being directly on the path of connection
+// establishment, so implementations of the CRL function need to be fast, and
+// slow things such as file IO should be done asynchronously.
 // TODO(erm-g): Add link to related gRFC once it's ready.
 // Please refer to https://github.com/grpc/proposal/ for more details.
 type CRLProvider interface {
@@ -47,9 +50,6 @@ type CRLProvider interface {
 // StaticCRLProvider implements CRLProvider interface by accepting raw content
 // of CRL files at creation time and storing parsed CRL structs  in-memory.
 type StaticCRLProvider struct {
-	// TODO CRL is sort of our internal representation - provide an API for
-	// people to read into it, or provide a simpler type in the API then
-	// internally convert to this form
 	crls map[string]*CRL
 }
 

security/advancedtls/crl_provider_test.go

@@ -128,7 +128,6 @@ func (s) TestFileWatcherCRLProviderConfig(t *testing.T) {
 // that it’s correctly processed. Additionally, we also check if number of
 // invocations of custom callback is correct.
 func (s) TestFileWatcherCRLProvider(t *testing.T) {
-	// testdata.Path("crl") contains 5 non-crl files.
 	nonCRLFilesSet := make(map[string]struct{})
 	customCallback := func(err error) {
 		nonCRLFilesSet[err.Error()] = struct{}{}