Add D-Bus method to get filesystem metadata

Signed-off-by: mulhern <[email protected]>

src/dbus_api/pool/mod.rs

@@ -260,6 +260,7 @@ pub fn create_dbus_pool<'a>(
                 .add_m(pool_3_0::rename_method(&f))
                 .add_m(pool_3_3::grow_physical_device_method(&f))
                 .add_m(pool_3_7::get_metadata_method(&f))
+                .add_m(pool_3_7::get_fs_metadata_method(&f))
                 .add_p(pool_3_0::name_property(&f))
                 .add_p(pool_3_0::uuid_property(&f))
                 .add_p(pool_3_0::encrypted_property(&f))

src/dbus_api/pool/pool_3_7/api.rs

@@ -7,7 +7,7 @@ use dbus_tree::{Access, EmitsChangedSignal, Factory, MTSync, Method, Property};
 use crate::dbus_api::{
     consts,
     pool::pool_3_7::{
-        methods::{destroy_filesystems, metadata},
+        methods::{destroy_filesystems, metadata, fs_metadata},
         props::get_pool_metadata_version,
     },
     types::TData,
@@ -47,3 +47,14 @@ pub fn metadata_version_property(
         .emits_changed(EmitsChangedSignal::Const)
         .on_get(get_pool_metadata_version)
 }
+
+pub fn get_fs_metadata_method(f: &Factory<MTSync<TData>, TData>) -> Method<MTSync<TData>, TData> {
+    f.method("FilesystemMetadata", (), fs_metadata)
+        // A string representing the pool's filesystem metadata in serialized
+        // JSON format.
+        //
+        // Rust representation: String
+        .out_arg(("results", "s"))
+        .out_arg(("return_code", "q"))
+        .out_arg(("return_string", "s"))
+}

src/dbus_api/pool/pool_3_7/methods.rs

@@ -148,3 +148,39 @@ pub fn metadata(m: &MethodInfo<'_, MTSync<TData>, TData>) -> MethodResult {
     };
     Ok(vec![msg])
 }
+
+pub fn fs_metadata(m: &MethodInfo<'_, MTSync<TData>, TData>) -> MethodResult {
+    let default_return = String::new();
+
+    let message: &Message = m.msg;
+
+    let return_message = message.method_return();
+
+    let dbus_context = m.tree.get_data();
+    let object_path = m.path.get_name();
+
+    let pool_path = m
+        .tree
+        .get(object_path)
+        .expect("implicit argument must be in tree");
+    let pool_uuid = typed_uuid!(
+        get_data!(pool_path; default_return; return_message).uuid;
+        Pool;
+        default_return;
+        return_message
+    );
+
+    let guard = get_pool!(dbus_context.engine; pool_uuid; default_return; return_message);
+    let (_, _, pool) = guard.as_tuple();
+
+    let result = pool.last_metadata();
+
+    let msg = match result {
+        Ok(v) => return_message.append3(v, DbusErrorEnum::OK as u16, OK_STRING.to_string()),
+        Err(err) => {
+            let (rc, rs) = engine_to_dbus_err_tuple(&err);
+            return_message.append3(default_return, rc, rs)
+        }
+    };
+    Ok(vec![msg])
+}

src/dbus_api/pool/pool_3_7/mod.rs

@@ -6,4 +6,7 @@ mod api;
 mod methods;
 mod props;
 
-pub use api::{destroy_filesystems_method, get_metadata_method, metadata_version_property};
+pub use api::{
+    destroy_filesystems_method, get_fs_metadata_method, get_metadata_method,
+    metadata_version_property,
+};

src/engine/engine.rs

@@ -350,6 +350,9 @@ pub trait Pool: Debug + Send + Sync {
 
     /// Get the metadata version for a given pool.
     fn metadata_version(&self) -> StratSigblockVersion;
+
+    /// Get the last written filesystem metadata.
+    fn last_fs_metadata(&self) -> StratisResult<String>;
 }
 
 pub type HandleEvents<P> = (

src/engine/sim_engine/pool.rs

@@ -758,6 +758,10 @@ impl Pool for SimPool {
     fn metadata_version(&self) -> StratSigblockVersion {
         StratSigblockVersion::V2
     }
+
+    fn last_fs_metadata(&self) -> StratisResult<String> {
+        unimplemented!()
+    }
 }
 
 #[cfg(test)]

src/engine/strat_engine/pool/shared.rs

@@ -348,4 +348,11 @@ impl Pool for AnyPool {
             AnyPool::V2(p) => p.metadata_version(),
         }
     }
+
+    fn last_fs_metadata(&self) -> StratisResult<String> {
+        match self {
+            AnyPool::V1(p) => p.last_fs_metadata(),
+            AnyPool::V2(p) => p.last_fs_metadata(),
+        }
+    }
 }

src/engine/strat_engine/pool/v1.rs

@@ -1293,6 +1293,10 @@ impl Pool for StratPool {
     fn metadata_version(&self) -> StratSigblockVersion {
         StratSigblockVersion::V1
     }
+
+    fn last_fs_metadata(&self) -> StratisResult<String> {
+        unimplemented!()
+    }
 }
 
 pub struct StratPoolState {

src/engine/strat_engine/pool/v2.rs

@@ -1200,6 +1200,10 @@ impl Pool for StratPool {
     fn metadata_version(&self) -> StratSigblockVersion {
         StratSigblockVersion::V2
     }
+
+    fn last_fs_metadata(&self) -> StratisResult<String> {
+        unimplemented!()
+    }
 }
 
 pub struct StratPoolState {