new file storage backend with additional tests. resolves #24

cmd/kmfddm/main.go

@@ -3,23 +3,18 @@ package main
 import (
 	"flag"
 	"fmt"
-	"hash"
 	"io"
 	"math/rand"
 	"net/http"
 	"os"
 	"time"
 
 	"github.com/alexedwards/flow"
-	"github.com/cespare/xxhash"
 	httpddm "github.com/jessepeterson/kmfddm/http"
 	apihttp "github.com/jessepeterson/kmfddm/http/api"
 	ddmhttp "github.com/jessepeterson/kmfddm/http/ddm"
 	"github.com/jessepeterson/kmfddm/log/stdlogfmt"
 	"github.com/jessepeterson/kmfddm/notifier"
-	"github.com/jessepeterson/kmfddm/storage/mysql"
-
-	_ "github.com/go-sql-driver/mysql"
 )
 
 // overridden by -ldflags -X
@@ -36,8 +31,8 @@ func main() {
 		flListen  = flag.String("listen", ":9002", "HTTP listen address")
 		flAPIKey  = flag.String("api", "", "API key for API endpoints")
 		flVersion = flag.Bool("version", false, "print version")
-		// flStorage = flag.String("storage", "", "storage backend")
-		flDSN = flag.String("storage-dsn", "", "storage data source name")
+		flStorage = flag.String("storage", "file", "storage backend")
+		flDSN     = flag.String("storage-dsn", "", "storage data source name")
 
 		flDumpStatus = flag.String("dump-status", "", "file name to dump status reports to (\"-\" for stdout)")
 
@@ -59,12 +54,9 @@ func main() {
 		logger.Info("msg", "empty API key; API disabled")
 	}
 
-	storage, err := mysql.New(
-		mysql.WithDSN(*flDSN),
-		mysql.WithNewHash(func() hash.Hash { return xxhash.New() }),
-	)
+	storage, err := storage(*flStorage, *flDSN)
 	if err != nil {
-		logger.Info("msg", "init MySQL storage", "err", err)
+		logger.Info("msg", "init storage", "name", *flStorage, "err", err)
 		os.Exit(1)
 	}
 

cmd/kmfddm/storage.go

@@ -0,0 +1,43 @@
+package main
+
+import (
+	"fmt"
+	"hash"
+
+	"github.com/cespare/xxhash"
+	"github.com/jessepeterson/kmfddm/http/api"
+	"github.com/jessepeterson/kmfddm/http/ddm"
+	"github.com/jessepeterson/kmfddm/notifier"
+	"github.com/jessepeterson/kmfddm/storage/file"
+	"github.com/jessepeterson/kmfddm/storage/mysql"
+
+	_ "github.com/go-sql-driver/mysql"
+)
+
+type allStorage interface {
+	notifier.EnrollmentIDFinder
+	api.SetAPIStorage
+	api.DeclarationAPIStorage
+	ddm.DeclarationRetriever
+	ddm.TokensDeclarationItemsRetriever
+	ddm.StatusStorage
+	api.EnrollmentAPIStorage
+	api.StatusAPIStorage
+}
+
+func storage(name, dsn string) (allStorage, error) {
+	switch name {
+	case "mysql":
+		return mysql.New(
+			mysql.WithDSN(dsn),
+			mysql.WithNewHash(func() hash.Hash { return xxhash.New() }),
+		)
+	case "file":
+		if dsn == "" {
+			dsn = "db"
+		}
+		return file.New(dsn)
+	default:
+		return nil, fmt.Errorf("unknown storage name: %s", name)
+	}
+}

storage/file/ddm.go

@@ -0,0 +1,162 @@
+package file
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"os"
+	"path"
+	"path/filepath"
+
+	"github.com/jessepeterson/kmfddm/ddm"
+)
+
+// RetrieveEnrollmentDeclarationJSON retrieves the DDM declaration JSON for an enrollment ID.
+func (s *File) RetrieveEnrollmentDeclarationJSON(_ context.Context, declarationID, declarationType, enrollmentID string) ([]byte, error) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return os.ReadFile(s.enrollmentDeclarationFilename(declarationID, declarationType, enrollmentID))
+}
+
+// RetrieveDeclarationItemsJSON retrieves the DDM declaration-items JSON for an enrollment ID.
+func (s *File) RetrieveDeclarationItemsJSON(_ context.Context, enrollmentID string) ([]byte, error) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return os.ReadFile(s.declarationItemsFilename(enrollmentID))
+}
+
+// RetrieveDeclarationItemsJSON retrieves the DDM token JSON for an enrollment ID.
+func (s *File) RetrieveTokensJSON(_ context.Context, enrollmentID string) ([]byte, error) {
+	s.mu.RLock()
+	defer s.mu.RUnlock()
+	return os.ReadFile(path.Join(s.path, enrollmentID, tokensFilename))
+}
+
+// writeDeclarationDDM looks up the enrollments associated with a declaration and writes the DDM files for each.
+func (s *File) writeDeclarationDDM(declarationID string) error {
+	// first find all enrollment IDs mapped to this declaration.
+	declarationIDs, err := s.declarationEnrollmentIDs(declarationID)
+	if err != nil {
+		return err
+	}
+	for _, id := range declarationIDs {
+		// write the enrollment DDM files
+		if err = s.writeEnrollmentDDM(id); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// writeSetDDM writes the DDM files for all enrollments belonging to a set.
+func (s *File) writeSetDDM(setName string) error {
+	// get all the enrollment ids for a this set
+	setEnrIDs, err := getSlice(s.setEnrollmentsFilename(setName))
+	if err != nil {
+		return err
+	}
+	for _, setEnrID := range setEnrIDs {
+		// write the enrollment DDM files
+		if err = s.writeEnrollmentDDM(setEnrID); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// writeEnrollmentDDM generates all enrollment ID-specific DDM declarations.
+func (s *File) writeEnrollmentDDM(enrollmentID string) error {
+	// get all the sets this id is enrolled in
+	enrollmentSets, err := getSlice(s.enrollmentSetsFilename(enrollmentID))
+	if err != nil {
+		return fmt.Errorf("getting sets for enrollment: %w", err)
+	}
+
+	enrollmentDeclarations := make(map[string]struct{})
+	for _, setName := range enrollmentSets {
+		// get all the declarations for this set
+		setDeclarations, err := getSlice(s.setFilename(setName))
+		if err != nil {
+			return fmt.Errorf("getting declarations from set for %s: %w", setName, err)
+		}
+		for _, declarationID := range setDeclarations {
+			// collect declaration IDs in our map
+			enrollmentDeclarations[declarationID] = struct{}{}
+		}
+	}
+
+	if err = s.assureEnrollmentDirExists(enrollmentID); err != nil {
+		return fmt.Errorf("assuring enrollment directory exists: %w", err)
+	}
+
+	// create our token and declaration-items builders
+	di := ddm.NewDIBuilder(s.newHash)
+	ti := ddm.NewTokensBuilder(s.newHash)
+
+	// find any existing declaration symlinks
+	matches, err := filepath.Glob(path.Join(s.path, enrollmentID, "declaration.*.json"))
+	if err != nil {
+		return fmt.Errorf("finding declaration symlinks: %w", err)
+	}
+
+	for declarationID := range enrollmentDeclarations {
+		// read and parse declaration
+		dBytes, err := os.ReadFile(s.declarationFilename(declarationID))
+		if err != nil {
+			return fmt.Errorf("reading declaration: %w", err)
+		}
+		d, err := ddm.ParseDeclaration(dBytes)
+		if err != nil {
+			return fmt.Errorf("parsing declaration: %w", err)
+		}
+
+		// add to our DI and tokens builders
+		di.AddDeclarationData(d)
+		ti.AddDeclarationData(d)
+
+		// create declaration symlink if not exists
+		symlinkName := s.enrollmentDeclarationFilename(d.Identifier, ddm.ManifestType(d.Type), enrollmentID)
+		if pos := contains(matches, symlinkName); pos >= 0 {
+			matches = append(matches[:pos], matches[pos+1:]...)
+		} else {
+			err = os.Symlink(
+				path.Join("..", relativeDeclarationFilename(d.Identifier)),
+				symlinkName,
+			)
+			if err != nil {
+				return fmt.Errorf("creating declaration symlink: %w", err)
+			}
+		}
+	}
+
+	// remove any symlinks for previous declarations
+	for _, oldSymlink := range matches {
+		if err = os.Remove(oldSymlink); err != nil {
+			return fmt.Errorf("removing declaration symlink: %w", err)
+		}
+	}
+
+	// finalize the builders
+	di.Finalize()
+	ti.Finalize()
+
+	// marshal and write the declarations-items JSON
+	diJSON, err := json.Marshal(&di.DeclarationItems)
+	if err != nil {
+		return err
+	}
+	if err = os.WriteFile(s.declarationItemsFilename(enrollmentID), diJSON, 0644); err != nil {
+		return err
+	}
+
+	// marshal and write the tokens JSON
+	tiJSON, err := json.Marshal(&ti.TokensResponse)
+	if err != nil {
+		return err
+	}
+	if err = os.WriteFile(s.tokensFilename(enrollmentID), tiJSON, 0644); err != nil {
+		return err
+	}
+
+	return nil
+}