filesystem: Globally declared filesystems, fs directive (#5833)

context.go

@@ -23,6 +23,8 @@ import (
 
 	"github.com/caddyserver/certmagic"
 	"go.uber.org/zap"
+
+	"github.com/caddyserver/caddy/v2/internal/filesystems"
 )
 
 // Context is a type which defines the lifetime of modules that
@@ -37,6 +39,7 @@ import (
 // not actually need to do this).
 type Context struct {
 	context.Context
+
 	moduleInstances map[string][]Module
 	cfg             *Config
 	cleanupFuncs    []func()
@@ -81,6 +84,15 @@ func (ctx *Context) OnCancel(f func()) {
 	ctx.cleanupFuncs = append(ctx.cleanupFuncs, f)
 }
 
+// Filesystems returns a ref to the FilesystemMap
+func (ctx *Context) Filesystems() FileSystems {
+	// if no config is loaded, we use a default filesystemmap, which includes the osfs
+	if ctx.cfg == nil {
+		return &filesystems.FilesystemMap{}
+	}
+	return ctx.cfg.filesystems
+}
+
 // LoadModule loads the Caddy module(s) from the specified field of the parent struct
 // pointer and returns the loaded module(s). The struct pointer and its field name as
 // a string are necessary so that reflection can be used to read the struct tag on the