Initial MVP commit

internal/platform/datasource/registry.go

@@ -0,0 +1,64 @@
+package datasource
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"gitea.maximumdirect.net/ejr/weatherapi/internal/platform/config"
+)
+
+// DataSource is a generic opened datasource handle.
+type DataSource interface {
+	Close()
+}
+
+// Factory constructs datasource handles for a specific driver.
+type Factory interface {
+	Driver() string
+	Open(ctx context.Context, cfg config.DatabaseConfig) (DataSource, error)
+}
+
+// Registry maps driver names to datasource factories.
+type Registry struct {
+	factories map[string]Factory
+}
+
+func NewRegistry() *Registry {
+	return &Registry{factories: map[string]Factory{}}
+}
+
+func (r *Registry) Register(factory Factory) error {
+	if factory == nil {
+		return fmt.Errorf("register datasource factory: factory is nil")
+	}
+	driver := normalizeDriver(factory.Driver())
+	if driver == "" {
+		return fmt.Errorf("register datasource factory: factory driver is empty")
+	}
+	if _, exists := r.factories[driver]; exists {
+		return fmt.Errorf("register datasource factory: driver %q already registered", driver)
+	}
+	r.factories[driver] = factory
+	return nil
+}
+
+func (r *Registry) Open(ctx context.Context, cfg config.DatabaseConfig) (DataSource, error) {
+	if r == nil {
+		return nil, fmt.Errorf("open datasource: registry is nil")
+	}
+	driver := normalizeDriver(cfg.Driver)
+	factory, ok := r.factories[driver]
+	if !ok {
+		return nil, fmt.Errorf("open datasource: unsupported driver %q", cfg.Driver)
+	}
+	ds, err := factory.Open(ctx, cfg)
+	if err != nil {
+		return nil, err
+	}
+	return ds, nil
+}
+
+func normalizeDriver(driver string) string {
+	return strings.ToLower(strings.TrimSpace(driver))
+}