Update GitUploader trait to use Option<ChangesetId> instead of Change…

…setId

Summary: Follow up of the previous diff, it changes the trait itself so we use `Option<ChangesetId>` to lowest layers possible. We can't go any further with `Option<ChangesetId>` because the thrift structures will change in a non-compatible way (especially for `BonsaiTagTarget`)

Reviewed By: gustavoavena

Differential Revision: D68438894

fbshipit-source-id: 2a96fda86f244fa70855dec5983658b4970c9c7a

eden/mononoke/git/import_direct/src/uploader.rs

@@ -38,6 +38,7 @@ use mononoke_api::repo::upload_non_blob_git_object;
 use mononoke_types::bonsai_changeset::BonsaiAnnotatedTag;
 use mononoke_types::bonsai_changeset::BonsaiAnnotatedTagTarget;
 use mononoke_types::hash;
+use mononoke_types::hash::Blake2;
 use mononoke_types::BonsaiChangeset;
 use mononoke_types::ChangesetId;
 use mononoke_types::FileChange;
@@ -182,9 +183,11 @@ where
     async fn generate_changeset_for_annotated_tag(
         &self,
         ctx: &CoreContext,
-        target_changeset_id: ChangesetId,
+        target_changeset_id: Option<ChangesetId>,
         mut tag: TagMetadata,
     ) -> Result<ChangesetId, Error> {
+        let target_changeset_id = target_changeset_id
+            .unwrap_or_else(|| ChangesetId::new(Blake2::from_byte_array([0; 32])));
         let annotated_tag = BonsaiAnnotatedTag {
             target: BonsaiAnnotatedTagTarget::Changeset(target_changeset_id),
             pgp_signature: tag.pgp_signature.take(),

eden/mononoke/git/import_tools/src/git_uploader.rs

@@ -163,7 +163,7 @@ pub trait GitUploader: Clone + Send + Sync + 'static {
     async fn generate_changeset_for_annotated_tag(
         &self,
         ctx: &CoreContext,
-        target_changeset_id: ChangesetId,
+        target_changeset_id: Option<ChangesetId>,
         tag: TagMetadata,
     ) -> Result<ChangesetId, Error>;
 

eden/mononoke/git/import_tools/src/lib.rs

@@ -226,7 +226,6 @@ pub async fn create_changeset_for_annotated_tag<Uploader: GitUploader, Reader: G
         .await
         .with_context(|| format_err!("Failed to create TagMetadata from git tag {}", tag_id))?;
     // Create the corresponding changeset for the Git Tag at Mononoke end
-    let original_changeset_id = original_changeset_id.unwrap_or_else(ChangesetId::empty);
     let changeset_id = uploader
         .generate_changeset_for_annotated_tag(ctx, original_changeset_id, tag_metadata)
         .await

eden/mononoke/mononoke_types/src/typed_hash.rs

@@ -94,12 +94,6 @@ where
 #[derive(mysql::OptTryFromRowField)]
 pub struct ChangesetId(Blake2);
 
-impl ChangesetId {
-    pub fn empty() -> Self {
-        Self(Blake2::from_byte_array([0; 32]))
-    }
-}
-
 /// An identifier for a changeset hash prefix in Mononoke.
 #[derive(Clone, Copy, Eq, PartialEq, Ord, PartialOrd, Debug, Hash, Abomonation)]
 pub struct ChangesetIdPrefix(Blake2Prefix);