Testing GCE detection in google default credentials.

4 files changed, 26 insertions, 2 deletions

diff --git a/src/core/security/credentials.h b/src/core/security/credentials.h
index 6d45895e77..3cd652cd57 100644
--- a/src/core/security/credentials.h
+++ b/src/core/security/credentials.h
@@ -93,6 +93,14 @@ typedef enum {
 /* It is the caller's responsibility to gpr_free the result if not NULL. */
 char *grpc_get_well_known_google_credentials_file_path(void);
 
+/* Implementation function for the different platforms. */
+char *grpc_get_well_known_google_credentials_file_path_impl(void);
+
+/* Override for testing only. Not thread-safe */
+typedef char *(*grpc_well_known_credentials_path_getter)(void);
+void grpc_override_well_known_credentials_path_getter(
+    grpc_well_known_credentials_path_getter getter);
+
 /* --- grpc_channel_credentials. --- */
 
 typedef struct {
@@ -201,6 +209,7 @@ grpc_credentials_status
 grpc_oauth2_token_fetcher_credentials_parse_server_response(
     const struct grpc_httpcli_response *response,
     grpc_credentials_md_store **token_md, gpr_timespec *token_lifetime);
+
 void grpc_flush_cached_google_default_credentials(void);
 
 /* Metadata-only credentials with the specified key and value where
diff --git a/src/core/security/credentials_posix.c b/src/core/security/credentials_posix.c
index 20f67a7f14..0c92bd4a96 100644
--- a/src/core/security/credentials_posix.c
+++ b/src/core/security/credentials_posix.c
@@ -44,7 +44,7 @@
 #include "src/core/support/env.h"
 #include "src/core/support/string.h"
 
-char *grpc_get_well_known_google_credentials_file_path(void) {
+char *grpc_get_well_known_google_credentials_file_path_impl(void) {
   char *result = NULL;
   char *home = gpr_getenv("HOME");
   if (home == NULL) {
diff --git a/src/core/security/credentials_win32.c b/src/core/security/credentials_win32.c
index 92dfd9bdfe..8ee9f706a1 100644
--- a/src/core/security/credentials_win32.c
+++ b/src/core/security/credentials_win32.c
@@ -44,7 +44,7 @@
 #include "src/core/support/env.h"
 #include "src/core/support/string.h"
 
-char *grpc_get_well_known_google_credentials_file_path(void) {
+char *grpc_get_well_known_google_credentials_file_path_impl(void) {
   char *result = NULL;
   char *appdata_path = gpr_getenv("APPDATA");
   if (appdata_path == NULL) {
diff --git a/src/core/security/google_default_credentials.c b/src/core/security/google_default_credentials.c
index 6a54fe4e47..5385e41130 100644
--- a/src/core/security/google_default_credentials.c
+++ b/src/core/security/google_default_credentials.c
@@ -241,5 +241,20 @@ void grpc_flush_cached_google_default_credentials(void) {
     grpc_channel_credentials_unref(default_credentials);
     default_credentials = NULL;
   }
+  compute_engine_detection_done = 0;
   gpr_mu_unlock(&g_mu);
 }
+
+/* -- Well known credentials path. -- */
+
+static grpc_well_known_credentials_path_getter creds_path_getter = NULL;
+
+char *grpc_get_well_known_google_credentials_file_path(void) {
+  if (creds_path_getter != NULL) return creds_path_getter();
+  return grpc_get_well_known_google_credentials_file_path_impl();
+}
+
+void grpc_override_well_known_credentials_path_getter(
+    grpc_well_known_credentials_path_getter getter) {
+  creds_path_getter = getter;
+}