sync new and updated containers to cluster store, no deletion yet

internal/machine/store/container.go

@@ -0,0 +1,23 @@
+package store
+
+import (
+	"time"
+	"uncloud/internal/machine/docker/container"
+)
+
+const (
+	// SyncStatusSynced indicates that a container record is synchronised with the Docker daemon. The record may
+	// become outdated even when the status is "synced" if the machine crashes or a network partition occurs.
+	// The cluster membership state of the machine should also be checked to determine if the record can be trusted.
+	SyncStatusSynced = "synced"
+	// SyncStatusOutdated indicates that a container record may be outdated, for example, due to being unable
+	// to retrieve the container's state from the Docker daemon or when the machine is being stopped or restarted.
+	SyncStatusOutdated = "outdated"
+)
+
+type ContainerRecord struct {
+	Container  *container.Container
+	MachineID  string
+	SyncStatus string
+	UpdatedAt  time.Time
+}

internal/machine/store/schema.sql

@@ -12,6 +12,7 @@ CREATE TABLE machines
     name TEXT AS (json_extract(info, '$.name')),
     -- info is a JSON-serialized MachineInfo protobuf message.
     info TEXT NOT NULL DEFAULT '{}' CHECK (json_valid(info))
+    -- TODO: add created_at and updated_at fields to track machine age and last update time.
 );
 
 -- containers table stores the Uncloud-managed Docker containers created in the cluster.

internal/machine/store/store.go

@@ -3,12 +3,14 @@ package store
 import (
 	"context"
 	_ "embed"
+	"encoding/json"
 	"errors"
 	"fmt"
 	"google.golang.org/protobuf/encoding/protojson"
 	"log/slog"
 	"uncloud/internal/corrosion"
 	"uncloud/internal/machine/api/pb"
+	"uncloud/internal/machine/docker/container"
 )
 
 var (
@@ -129,3 +131,32 @@ func (s *Store) SubscribeMachines(ctx context.Context) ([]*pb.MachineInfo, <-cha
 
 	return machines, changes, nil
 }
+
+// CreateOrUpdateContainer creates a new container record or updates an existing one in the store database.
+// The container is associated with the given machine ID that indicates which machine the container is running on.
+func (s *Store) CreateOrUpdateContainer(ctx context.Context, c *container.Container, machineID string) error {
+	cJSON, err := json.Marshal(c)
+	if err != nil {
+		return fmt.Errorf("marshal container: %w", err)
+	}
+
+	// Insert or update the container record if the container or machine ID has changed.
+	res, err := s.corro.ExecContext(ctx, `
+		INSERT INTO containers (id, container, machine_id, sync_status, updated_at)
+		VALUES (?, ?, ?, ?, datetime('now'))
+		ON CONFLICT (id) DO UPDATE SET container   = excluded.container,
+									   machine_id  = excluded.machine_id,
+									   sync_status = excluded.sync_status,
+									   updated_at  = excluded.updated_at
+		WHERE containers.container != excluded.container
+		  OR containers.machine_id != excluded.machine_id`,
+		c.ID, string(cJSON), machineID, SyncStatusSynced)
+	if err != nil {
+		return fmt.Errorf("upsert query: %w", err)
+	}
+	if res.RowsAffected > 0 {
+		slog.Debug("Container record updated in store DB.", "id", c.ID, "machine_id", machineID)
+	}
+
+	return nil
+}