receivepack: Add service semantics thingy

1 files changed, 88 insertions, 0 deletions

diff --git a/receivepack/internal/service/execute.go b/receivepack/internal/service/execute.go
new file mode 100644
index 00000000..b3d47d29
--- /dev/null
+++ b/receivepack/internal/service/execute.go
@@ -0,0 +1,88 @@
+package service
+
+import (
+	"context"
+	"log"
+
+	"codeberg.org/lindenii/furgit/format/pack/ingest"
+)
+
+// Execute validates one receive-pack request, optionally ingests its pack into
+// quarantine, and plans ref updates.
+//
+// TODO: Invoke hook or policy callbacks to decide whether each planned update
+// should be allowed.
+// TODO: Apply planned ref updates with one atomic compare-and-swap ref
+// transaction once ref writing exists.
+func (service *Service) Execute(ctx context.Context, req *Request) (*Result, error) {
+	_ = ctx
+
+	result := &Result{
+		Commands: make([]CommandResult, 0, len(req.Commands)),
+	}
+
+	if req.PackExpected {
+		if req.Pack == nil {
+			result.UnpackError = "missing pack stream"
+			fillCommandErrors(result, req.Commands, "missing pack stream")
+
+			return result, nil
+		}
+
+		if service.opts.ObjectsRoot == nil {
+			result.UnpackError = "objects root not configured"
+			fillCommandErrors(result, req.Commands, "objects root not configured")
+
+			return result, nil
+		}
+
+		quarantineName, quarantineRoot, err := service.createQuarantineRoot()
+		if err != nil {
+			result.UnpackError = err.Error()
+			fillCommandErrors(result, req.Commands, err.Error())
+
+			return result, nil
+		}
+
+		defer func() {
+			_ = quarantineRoot.Close()
+			// TODO: Promote accepted quarantined objects into the permanent object
+			// store once atomic ref application exists.
+			_ = service.opts.ObjectsRoot.RemoveAll(quarantineName)
+		}()
+
+		ingested, err := ingest.Ingest(
+			req.Pack,
+			quarantineRoot,
+			service.opts.Algorithm,
+			true,
+			true,
+			service.opts.ExistingObjects,
+		)
+		if err != nil {
+			result.UnpackError = err.Error()
+			fillCommandErrors(result, req.Commands, err.Error())
+
+			return result, nil
+		}
+
+		result.Ingest = &ingested
+	}
+
+	for _, command := range req.Commands {
+		result.Planned = append(result.Planned, PlannedUpdate{
+			Name:   command.Name,
+			OldID:  command.OldID,
+			NewID:  command.NewID,
+			Delete: isDelete(command),
+		})
+	}
+
+	fillCommandErrors(result, req.Commands, "ref updates not implemented yet")
+	log.Printf(
+		"receivepack: planned %d ref updates, but hook/policy checks and atomic ref writes are not implemented yet",
+		len(result.Planned),
+	)
+
+	return result, nil
+}