Add OCI (Oracle Cloud Infrastructure) cloud provider support

pkg/config/config.go

@@ -32,6 +32,7 @@ const (
 	CloudProviderAWS   CloudProvider = "AWS"
 	CloudProviderAzure CloudProvider = "Azure"
 	CloudProviderGCP   CloudProvider = "GCP"
+	CloudProviderOCI   CloudProvider = "OCI"
 )
 
 func Get() *Cfg {
@@ -61,6 +62,8 @@ func ParseCloudProvider(s string) CloudProvider {
 		return CloudProviderAzure
 	case "gcp":
 		return CloudProviderGCP
+	case "oci":
+		return CloudProviderOCI
 	default:
 		return CloudProviderNone
 	}

pkg/postgres/oci.go

@@ -0,0 +1,50 @@
+package postgres
+
+import (
+	"fmt"
+
+	"github.com/lib/pq"
+)
+
+type ocipg struct {
+	pg
+}
+
+func newOCIPG(postgres *pg) PG {
+	return &ocipg{
+		*postgres,
+	}
+}
+
+func (c *ocipg) CreateDB(dbname, role string) error {
+	// OCI managed Postgres admin user is not a true superuser; must belong to
+	// the role before ALTER DATABASE ... OWNER TO succeeds
+	err := c.GrantRole(role, c.user)
+	if err != nil {
+		return err
+	}
+
+	return c.pg.CreateDB(dbname, role)
+}
+
+func (c *ocipg) DropRole(role, newOwner, database string) error {
+	// Must belong to both roles for REASSIGN OWNED BY to succeed
+	err := c.GrantRole(role, c.user)
+	if err != nil && err.(*pq.Error).Code != "0LP01" {
+		if err.(*pq.Error).Code == "42704" {
+			return nil
+		}
+		return err
+	}
+	err = c.GrantRole(newOwner, c.user)
+	if err != nil && err.(*pq.Error).Code != "0LP01" {
+		if err.(*pq.Error).Code == "42704" {
+			c.log.Info(fmt.Sprintf("not granting %s to %s as %s does not exist", role, newOwner, newOwner))
+			return nil
+		}
+		return err
+	}
+	defer c.RevokeRole(newOwner, c.user)
+
+	return c.pg.DropRole(role, newOwner, database)
+}

pkg/postgres/postgres.go

@@ -79,6 +79,9 @@ func NewPG(cfg *config.Cfg, logger logr.Logger) (PG, error) {
 	case config.CloudProviderGCP:
 		logger.Info("Using GCP wrapper")
 		return newGCPPG(postgres), nil
+	case config.CloudProviderOCI:
+		logger.Info("Using OCI wrapper")
+		return newOCIPG(postgres), nil
 	default:
 		logger.Info("Using default postgres implementation")
 		return postgres, nil