feat(3p/nix): Implement AddToStore proto handler r/1519

Implement the proto handler for AddToStore, which adds a nix path to the
store. This is implemented by adding a new (probably
soon-to-be-generalized) Source concretion that wraps a grpc ServerReader
for the stream of data we're receiving from the client - this is less
than ideal, as it's perpetuating the source/sink thing that's going on
and storing entire nars in memory, but is at the very worst an
incremental step towards a functioning nix that we can refactor in the
future.

Paired-With: Perry Lorier <isomer@tvl.fyi>
Paired-With: Vincent Ambo <mail@tazj.in>
Change-Id: I48db734e7460a47aee4a85dd5137b690980859e3
Reviewed-on: https://cl.tvl.fyi/c/depot/+/1441
Tested-by: BuildkiteCI
Reviewed-by: kanepyork <rikingcoding@gmail.com>
Reviewed-by: tazjin <mail@tazj.in>

1 files changed, 2 insertions, 7 deletions

diff --git a/third_party/nix/src/proto/worker.proto b/third_party/nix/src/proto/worker.proto
index 3ddaa575e7f4..e2ff598b2c9b 100644
--- a/third_party/nix/src/proto/worker.proto
+++ b/third_party/nix/src/proto/worker.proto
@@ -17,7 +17,7 @@ service WorkerService {
   // Query referrers for a given path.
   rpc QueryReferrers(StorePath) returns (StorePaths);
 
-  // Add a NAR (I think?) to the store. The first stream request
+  // Add a path to the store. The first stream request
   // should be a message indicating metadata, the rest should be file
   // chunks.
   rpc AddToStore(stream AddToStoreRequest) returns (StorePath);
@@ -185,14 +185,9 @@ message AddToStoreRequest {
     string base_name = 4;
   }
 
-  message Chunk {
-    bytes content = 1;
-    bool final = 2;
-  }
-
   oneof add_oneof {
     Metadata meta = 1;
-    Chunk chunk = 2;
+    bytes data = 3;
   }
 }