walker: specify cache-mode default

Summary: Walker previously specified a default for the deprecated `cachelib-only-blobstore` argument.  Switch to `cache-mode`, allowing us to specify local caching for all types, not just the blobstore.

Differential Revision: D45089769

fbshipit-source-id: 978ac545590935be5a825669db9df58f0281c41a

eden/mononoke/cmdlib/caching/Cargo.toml

@@ -9,6 +9,7 @@ license = "GPLv2+"
 
 [dependencies]
 anyhow = "1.0.65"
+arg_extensions = { version = "0.1.0", path = "../extensions" }
 cachelib = { version = "0.1.0", git = "https://github.com/facebookexperimental/rust-shed.git", branch = "main" }
 clap = { version = "4.2.4", features = ["derive", "env", "string", "unicode", "wrap_help"] }
 environment = { version = "0.1.0", path = "../environment" }

eden/mononoke/cmdlib/caching/src/args.rs

@@ -5,6 +5,7 @@
  * GNU General Public License version 2.
  */
 
+use arg_extensions::ArgDefaults;
 use clap::ArgAction;
 use clap::Args;
 use clap::ValueEnum;
@@ -21,6 +22,18 @@ pub enum CacheMode {
     Disabled,
 }
 
+impl ArgDefaults for CacheMode {
+    fn arg_defaults(&self) -> Vec<(&'static str, String)> {
+        vec![(
+            "cache_mode",
+            self.to_possible_value()
+                .expect("default value must exist")
+                .get_name()
+                .to_string(),
+        )]
+    }
+}
+
 #[derive(Args, Debug)]
 pub struct CachelibArgs {
     /// Mode to initialize caching in.

eden/mononoke/walker/src/main.rs

@@ -19,6 +19,7 @@ use blobstore_factory::BlobstoreArgDefaults;
 use blobstore_factory::ReadOnlyStorage;
 use clap::ArgGroup;
 use clap::Parser;
+use cmdlib_caching::CacheMode;
 use cmdlib_caching::CachelibSettings;
 use cmdlib_scrubbing::ScrubAppExtension;
 use fbinit::FacebookInit;
@@ -63,7 +64,6 @@ fn main(fb: FacebookInit) -> Result<(), Error> {
 
     let cachelib_defaults = CachelibSettings {
         cache_size: 2 * 1024 * 1024 * 1024,
-        blobstore_cachelib_only: true,
         ..Default::default()
     };
 
@@ -85,6 +85,7 @@ fn main(fb: FacebookInit) -> Result<(), Error> {
     let app = MononokeAppBuilder::new(fb)
         .with_app_extension(scrub_extension)
         .with_default_cachelib_settings(cachelib_defaults)
+        .with_arg_defaults(CacheMode::LocalOnly)
         .with_arg_defaults(blobstore_defaults)
         .with_arg_defaults(read_only_storage)
         .with_app_extension(Fb303AppExtension {})