Start simple filesystem storage backend

cmd/tokidoki/main.go

@@ -41,7 +41,11 @@ func main() {
 	}
 	mux.Use(authProvider.Middleware())
 
-	backend := storage.NewPostgreSQL()
+	//backend := storage.NewPostgreSQL()
+	backend, err := storage.NewFilesystem("./teststorage")
+	if err != nil {
+		log.Fatalf("failed to load storage backend: %s", err.Error())
+	}
 	mux.Mount("/", &carddav.Handler{Backend: backend})
 
 	server := http.Server{

storage/filesystem.go

@@ -1,42 +1,134 @@
 package storage
 
 import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"os"
+	"path/filepath"
+
 	"github.com/emersion/go-vcard"
 	"github.com/emersion/go-webdav/carddav"
+
+	"git.sr.ht/~sircmpwn/tokidoki/auth"
 )
 
 type filesystemBackend struct {
 	path string
 }
 
-var _ carddav.Backend = (*filesystemBackend)(nil)
+var nilBackend carddav.Backend = (*filesystemBackend)(nil)
 
-func NewfilesystemBackend(path string) carddav.Backend {
+func NewFilesystem(path string) (carddav.Backend, error) {
+	info, err := os.Stat(path)
+	if err != nil {
+		return nilBackend, fmt.Errorf("failed to create filesystem backend: %s", err.Error())
+	}
+	if !info.IsDir() {
+		return nilBackend, fmt.Errorf("base path for filesystem backend must be a directory")
+	}
 	return &filesystemBackend{
 		path: path,
+	}, nil
+}
+
+func (b *filesystemBackend) pathForContext(ctx context.Context) (string, error) {
+	raw := ctx.Value(auth.AuthCtxKey)
+	if raw == nil {
+		return b.path, nil
 	}
+	authCtx, ok := raw.(*auth.AuthContext)
+	if !ok {
+		panic("Invalid data in auth context!")
+	}
+	//TODO sanitize user name or at least check if valid dir name?
+	path := filepath.Join(b.path, authCtx.UserName)
+
+	_, err := os.Stat(path)
+	if os.IsNotExist(err) {
+		err = os.Mkdir(path, 0755)
+		if err != nil {
+			return "", fmt.Errorf("error creating '%s': %s", path, err.Error())
+		}
+	}
+	return path, nil
 }
 
-func (*filesystemBackend) AddressBook() (*carddav.AddressBook, error) {
-	panic("TODO")
+func createDefaultAddressBook(path string) error {
+	// TODO what should the default address book look like?
+	defaultAB := carddav.AddressBook{
+		Path:                 "/default",
+		Name:                 "My contacts",
+		Description:          "Default address book",
+		MaxResourceSize:      1024,
+		SupportedAddressData: []carddav.AddressDataType{},
+	}
+	blob, err := json.MarshalIndent(defaultAB, "", "  ")
+	if err != nil {
+		return fmt.Errorf("error creating default address book: %s", err.Error())
+	}
+	err = os.WriteFile(path, blob, 0644)
+	if err != nil {
+		return fmt.Errorf("error writing default address book: %s", err.Error())
+	}
+	return nil
 }
 
-func (*filesystemBackend) GetAddressObject(path string, req *carddav.AddressDataRequest) (*carddav.AddressObject, error) {
-	panic("TODO")
+func (b *filesystemBackend) AddressBook(ctx context.Context) (*carddav.AddressBook, error) {
+	path, err := b.pathForContext(ctx)
+	if err != nil {
+		return nil, err
+	}
+	path = filepath.Join(path, "default.json")
+	_, err = os.Stat(path)
+	if os.IsNotExist(err) {
+		err = createDefaultAddressBook(path)
+		if err != nil {
+			return nil, err
+		}
+	} else if err != nil {
+		return nil, fmt.Errorf("error opening address book: %s", err.Error())
+	}
+
+	data, err := ioutil.ReadFile(path)
+	if err != nil {
+		return nil, fmt.Errorf("error opening address book: %s", err.Error())
+	}
+	var addressBook carddav.AddressBook
+	err = json.Unmarshal(data, &addressBook)
+	if err != nil {
+		return nil, fmt.Errorf("error reading address book: %s", err.Error())
+	}
+
+	return &addressBook, nil
 }
 
-func (*filesystemBackend) ListAddressObjects(req *carddav.AddressDataRequest) ([]carddav.AddressObject, error) {
-	panic("TODO")
+func (*filesystemBackend) GetAddressObject(ctx context.Context, path string, req *carddav.AddressDataRequest) (*carddav.AddressObject, error) {
+	//TODO
+	log.Fatalf("PutAddressObject(ctx, '%s', req): not implemented", path)
+	return nil, nil
 }
 
-func (*filesystemBackend) QueryAddressObjects(query *carddav.AddressBookQuery) ([]carddav.AddressObject, error) {
-	panic("TODO")
+func (*filesystemBackend) ListAddressObjects(ctx context.Context, req *carddav.AddressDataRequest) ([]carddav.AddressObject, error) {
+	return []carddav.AddressObject{}, nil
+	//panic("TODO")
 }
 
-func (*filesystemBackend) PutAddressObject(path string, card vcard.Card) (loc string, err error) {
-	panic("TODO")
+func (*filesystemBackend) QueryAddressObjects(ctx context.Context, query *carddav.AddressBookQuery) ([]carddav.AddressObject, error) {
+	return []carddav.AddressObject{}, nil
+	//panic("TODO")
 }
 
-func (*filesystemBackend) DeleteAddressObject(path string) error {
-	panic("TODO")
+func (*filesystemBackend) PutAddressObject(ctx context.Context, path string, card vcard.Card) (loc string, err error) {
+	//TODO
+	log.Fatalf("PutAddressObject(ctx, '%s', card): not implemented", path)
+	return "", nil
+}
+
+func (*filesystemBackend) DeleteAddressObject(ctx context.Context, path string) error {
+	//TODO
+	log.Fatalf("DeleteAddressObject(ctx, '%s'): not implemented", path)
+	return nil
 }