package responsemodifiers import ( "context" "net/http" "github.com/containous/traefik/v2/pkg/config/runtime" "github.com/containous/traefik/v2/pkg/server/provider" ) // NewBuilder creates a builder. func NewBuilder(configs map[string]*runtime.MiddlewareInfo) *Builder { return &Builder{configs: configs} } // Builder holds builder configuration. type Builder struct { configs map[string]*runtime.MiddlewareInfo } // Build Builds the response modifier. // It returns nil if there is no modifier to apply. func (f *Builder) Build(ctx context.Context, names []string) func(*http.Response) error { var modifiers []func(*http.Response) error for _, middleName := range names { conf, ok := f.configs[middleName] if !ok { getLogger(ctx, middleName, "undefined").Debug("Middleware name not found in config (ResponseModifier)") continue } if conf == nil || conf.Middleware == nil { getLogger(ctx, middleName, "undefined").Error("Invalid Middleware configuration (ResponseModifier)") continue } if conf.Headers != nil { getLogger(ctx, middleName, "Headers").Debug("Creating Middleware (ResponseModifier)") modifiers = append(modifiers, buildHeaders(conf.Headers, middleName)) } else if conf.Chain != nil { chainCtx := provider.AddInContext(ctx, middleName) getLogger(chainCtx, middleName, "Chain").Debug("Creating Middleware (ResponseModifier)") var qualifiedNames []string for _, name := range conf.Chain.Middlewares { qualifiedNames = append(qualifiedNames, provider.GetQualifiedName(chainCtx, name)) } if rm := f.Build(ctx, qualifiedNames); rm != nil { modifiers = append(modifiers, rm) } } } if len(modifiers) > 0 { return func(resp *http.Response) error { for i := len(modifiers); i > 0; i-- { err := modifiers[i-1](resp) if err != nil { return err } } return nil } } return nil }