feat(3p/nix/daemon): catch-all explicit Error-Status conversion r/1573

We wrap every server-side proto handler with a macro that catches
exceptions and turns them into proper grpc error codes. For the
time being, most exceptions map to INTERNAL, the existing mapping.

Change-Id: Id6ed6a279b198ad185d32562f39000ccc15eadbf
Reviewed-on: https://cl.tvl.fyi/c/depot/+/1599
Tested-by: BuildkiteCI
Reviewed-by: glittershark <grfn@gws.fyi>

1 files changed, 95 insertions, 3 deletions

diff --git a/third_party/nix/src/libstore/rpc-store.cc b/third_party/nix/src/libstore/rpc-store.cc
index 4a55e09967..9c7c662356 100644
--- a/third_party/nix/src/libstore/rpc-store.cc
+++ b/third_party/nix/src/libstore/rpc-store.cc
@@ -3,6 +3,7 @@
 #include <algorithm>
 #include <memory>
 
+#include <absl/status/status.h>
 #include <absl/strings/str_cat.h>
 #include <absl/strings/str_format.h>
 #include <google/protobuf/empty.pb.h>
@@ -52,14 +53,105 @@ T FillFrom(const U& src) {
   return result;
 }
 
+constexpr absl::StatusCode GRPCStatusCodeToAbsl(grpc::StatusCode code) {
+  switch (code) {
+    case grpc::StatusCode::OK:
+      return absl::StatusCode::kOk;
+    case grpc::StatusCode::CANCELLED:
+      return absl::StatusCode::kCancelled;
+    case grpc::StatusCode::UNKNOWN:
+      return absl::StatusCode::kUnknown;
+    case grpc::StatusCode::INVALID_ARGUMENT:
+      return absl::StatusCode::kInvalidArgument;
+    case grpc::StatusCode::DEADLINE_EXCEEDED:
+      return absl::StatusCode::kDeadlineExceeded;
+    case grpc::StatusCode::NOT_FOUND:
+      return absl::StatusCode::kNotFound;
+    case grpc::StatusCode::ALREADY_EXISTS:
+      return absl::StatusCode::kAlreadyExists;
+    case grpc::StatusCode::PERMISSION_DENIED:
+      return absl::StatusCode::kPermissionDenied;
+    case grpc::StatusCode::UNAUTHENTICATED:
+      return absl::StatusCode::kUnauthenticated;
+    case grpc::StatusCode::RESOURCE_EXHAUSTED:
+      return absl::StatusCode::kResourceExhausted;
+    case grpc::StatusCode::FAILED_PRECONDITION:
+      return absl::StatusCode::kFailedPrecondition;
+    case grpc::StatusCode::ABORTED:
+      return absl::StatusCode::kAborted;
+    case grpc::StatusCode::OUT_OF_RANGE:
+      return absl::StatusCode::kOutOfRange;
+    case grpc::StatusCode::UNIMPLEMENTED:
+      return absl::StatusCode::kUnimplemented;
+    case grpc::StatusCode::INTERNAL:
+      return absl::StatusCode::kInternal;
+    case grpc::StatusCode::UNAVAILABLE:
+      return absl::StatusCode::kUnavailable;
+    case grpc::StatusCode::DATA_LOSS:
+      return absl::StatusCode::kDataLoss;
+    default:
+      return absl::StatusCode::kInternal;
+  }
+}
+
+constexpr absl::string_view GRPCStatusCodeDescription(grpc::StatusCode code) {
+  switch (code) {
+    case grpc::StatusCode::OK:
+      return "OK";
+    case grpc::StatusCode::CANCELLED:
+      return "CANCELLED";
+    case grpc::StatusCode::UNKNOWN:
+      return "UNKNOWN";
+    case grpc::StatusCode::INVALID_ARGUMENT:
+      return "INVALID_ARGUMENT";
+    case grpc::StatusCode::DEADLINE_EXCEEDED:
+      return "DEADLINE_EXCEEDED";
+    case grpc::StatusCode::NOT_FOUND:
+      return "NOT_FOUND";
+    case grpc::StatusCode::ALREADY_EXISTS:
+      return "ALREADY_EXISTS";
+    case grpc::StatusCode::PERMISSION_DENIED:
+      return "PERMISSION_DENIED";
+    case grpc::StatusCode::UNAUTHENTICATED:
+      return "UNAUTHENTICATED";
+    case grpc::StatusCode::RESOURCE_EXHAUSTED:
+      return "RESOURCE_EXHAUSTED";
+    case grpc::StatusCode::FAILED_PRECONDITION:
+      return "FAILED_PRECONDITION";
+    case grpc::StatusCode::ABORTED:
+      return "ABORTED";
+    case grpc::StatusCode::OUT_OF_RANGE:
+      return "OUT_OF_RANGE";
+    case grpc::StatusCode::UNIMPLEMENTED:
+      return "UNIMPLEMENTED";
+    case grpc::StatusCode::INTERNAL:
+      return "INTERNAL";
+    case grpc::StatusCode::UNAVAILABLE:
+      return "UNAVAILABLE";
+    case grpc::StatusCode::DATA_LOSS:
+      return "DATA_LOSS";
+    default:
+      return "<BAD ERROR CODE>";
+  };
+}
+
 // TODO(grfn): Obviously this should go away and be replaced by StatusOr... but
 // that would require refactoring the entire store api, which we don't feel like
 // doing right now. We should at some point though
 void const RpcStore::SuccessOrThrow(const grpc::Status& status) const {
   if (!status.ok()) {
-    throw Error(absl::StrFormat("Rpc call to %s failed (%d): %s ",
-                                uri_.value_or("unknown URI"),
-                                status.error_code(), status.error_message()));
+    auto uri = uri_.value_or("unknown URI");
+    switch (status.error_code()) {
+      case grpc::StatusCode::UNIMPLEMENTED:
+        throw Unsupported(
+            absl::StrFormat("operation is not supported by store at %s: %s",
+                            uri, status.error_message()));
+      default:
+        throw Error(
+            absl::StrFormat("Rpc call to %s failed (%s): %s ", uri,
+                            GRPCStatusCodeDescription(status.error_code()),
+                            status.error_message()));
+    }
   }
 }