workers: Pass a map of input filenames -> digest of file contents to workers so that they can cache and reuse state for unchanged inputs over multiple builds.

--
MOS_MIGRATED_REVID=107066408

1 files changed, 18 insertions, 0 deletions

diff --git a/src/main/protobuf/worker_protocol.proto b/src/main/protobuf/worker_protocol.proto
index 66926cce44..4706792f4e 100644
--- a/src/main/protobuf/worker_protocol.proto
+++ b/src/main/protobuf/worker_protocol.proto
@@ -18,14 +18,32 @@ package blaze.worker;
 
 option java_package = "com.google.devtools.build.lib.worker";
 
+// An input file.
+message Input {
+  // The path in the file system where to read this input artifact from. This is
+  // either a path relative to the execution root (the worker process is
+  // launched with the working directory set to the execution root), or an
+  // absolute path.
+  string path = 1;
+
+  // A hash-value of the contents. The format of the contents is unspecified and
+  // the digest should be treated as an opaque token.
+  bytes digest = 2;
+}
+
 // This represents a single work unit that Blaze sends to the worker.
 message WorkRequest {
   repeated string arguments = 1;
+
+  // The inputs that the worker is allowed to read during execution of this
+  // request.
+  repeated Input inputs = 2;
 }
 
 // The worker sends this message to Blaze when it finished its work on the WorkRequest message.
 message WorkResponse {
   int32 exit_code = 1;
+
   // This is printed to the user after the WorkResponse has been received and is supposed to contain
   // compiler warnings / errors etc. - thus we'll use a string type here, which gives us UTF-8
   // encoding.