feat: add support for GCS Store using tonic/grpc

nativelink-config/src/stores.rs

@@ -54,6 +54,9 @@ pub enum StoreSpec {
     ///
     memory(MemorySpec),
 
+    /// TODO(asr2003): Add documentation.
+    experimental_gcs_store(GCSSpec),
+
     /// S3 store will use Amazon's S3 service as a backend to store
     /// the files. This configuration can be used to share files
     /// across multiple instances.
@@ -724,6 +727,61 @@ pub struct EvictionPolicy {
     pub max_count: u64,
 }
 
+#[derive(Serialize, Deserialize, Debug, Default, Clone)]
+#[serde(deny_unknown_fields)]
+pub struct GCSSpec {
+    /// GCS region or location. Example: US, US-CENTRAL1, EUROPE-WEST1.
+    #[serde(default, deserialize_with = "convert_string_with_shellexpand")]
+    pub location: String,
+
+    /// Bucket name to use as the backend.
+    #[serde(default, deserialize_with = "convert_string_with_shellexpand")]
+    pub bucket: String,
+
+    /// Optional prefix for object keys. If None, no prefix will be used.
+    #[serde(default)]
+    pub key_prefix: Option<String>,
+
+    /// Retry configuration to use when a network request fails.
+    #[serde(default)]
+    pub retry: Retry,
+
+    /// Time in seconds after which an object is considered "expired."
+    /// Allows external tools to clean up unused objects.
+    /// Default: 0. Zero means never consider an object expired.
+    #[serde(default, deserialize_with = "convert_duration_with_shellexpand")]
+    pub consider_expired_after_s: u32,
+
+    /// Maximum buffer size to retain in case of a retryable error during upload.
+    /// Setting this to zero will disable upload buffering.
+    /// Default: 5MB.
+    pub max_retry_buffer_per_request: Option<usize>,
+
+    /// Enable resumable uploads for large objects.
+    /// Default: true.
+    #[serde(default)]
+    pub enable_resumable_uploads: bool,
+
+    /// The maximum size of chunks (in bytes) for resumable uploads.
+    /// Default: 8MB.
+    pub resumable_chunk_size: Option<usize>,
+
+    /// Allow unencrypted HTTP connections. Only use this for local testing.
+    /// Default: false
+    #[serde(default)]
+    pub insecure_allow_http: bool,
+
+    /// Disable http/2 connections and only use http/1.1.
+    /// Default: false
+    #[serde(default)]
+    pub disable_http2: bool,
+
+    /// Optional configuration for client authentication.
+    /// Example: Path to a service account JSON key file or environment-based authentication.
+    #[serde(default)]
+    pub auth_key_file: Option<String>,
+}
+
 #[derive(Serialize, Deserialize, Debug, Default, Clone)]
 #[serde(deny_unknown_fields)]
 pub struct S3Spec {

nativelink-store/BUILD.bazel

@@ -18,6 +18,7 @@ rust_library(
         "src/existence_cache_store.rs",
         "src/fast_slow_store.rs",
         "src/filesystem_store.rs",
+        "src/gcs_store.rs",
         "src/grpc_store.rs",
         "src/lib.rs",
         "src/memory_store.rs",
@@ -52,9 +53,11 @@ rust_library(
         "@crates//:bytes",
         "@crates//:bytes-utils",
         "@crates//:const_format",
+        "@crates//:crc32c",
         "@crates//:filetime",
         "@crates//:fred",
         "@crates//:futures",
+        "@crates//:googleapis-tonic-google-storage-v2",
         "@crates//:hex",
         "@crates//:http-body",
         "@crates//:hyper-0.14.31",

nativelink-store/Cargo.toml

@@ -57,6 +57,8 @@ tokio-util = { version = "0.7.13" }
 tonic = { version = "0.12.3", features = ["transport", "tls"], default-features = false }
 tracing = { version = "0.1.41", default-features = false }
 uuid = { version = "1.11.0", default-features = false, features = ["v4", "serde"] }
+googleapis-tonic-google-storage-v2 = "0.16.0"
+crc32c = "0.6.8"
 
 [dev-dependencies]
 nativelink-macro = { path = "../nativelink-macro" }

nativelink-store/src/default_store_factory.rs

@@ -29,6 +29,7 @@ use crate::dedup_store::DedupStore;
 use crate::existence_cache_store::ExistenceCacheStore;
 use crate::fast_slow_store::FastSlowStore;
 use crate::filesystem_store::FilesystemStore;
+use crate::gcs_store::GCSStore;
 use crate::grpc_store::GrpcStore;
 use crate::memory_store::MemoryStore;
 use crate::noop_store::NoopStore;
@@ -51,6 +52,7 @@ pub fn store_factory<'a>(
         let store: Arc<dyn StoreDriver> = match backend {
             StoreSpec::memory(spec) => MemoryStore::new(spec),
             StoreSpec::experimental_s3_store(spec) => S3Store::new(spec, SystemTime::now).await?,
+            StoreSpec::experimental_gcs_store(spec) => GCSStore::new(spec, SystemTime::now).await?,
             StoreSpec::redis_store(spec) => RedisStore::new(spec.clone())?,
             StoreSpec::verify(spec) => VerifyStore::new(
                 spec,