Add different data providers and improve docs

This adds support for switching between in-memory, local filesystem, s3
or sqlite.

stores/aws/documents.go

@@ -0,0 +1,71 @@
+package aws
+
+import (
+	"bytes"
+	"context"
+	"excalidraw-complete/core"
+	"fmt"
+	"io/ioutil"
+	"log"
+
+	"github.com/aws/aws-sdk-go-v2/aws"
+	"github.com/aws/aws-sdk-go-v2/config"
+	"github.com/aws/aws-sdk-go-v2/service/s3"
+	"github.com/oklog/ulid/v2"
+)
+
+type documentStore struct {
+	s3Client *s3.Client
+	bucket   string // Name of the S3 bucket
+}
+
+func NewDocumentStore(bucketName string) core.DocumentStore {
+	cfg, err := config.LoadDefaultConfig(context.TODO())
+	if err != nil {
+		log.Fatalf("unable to load SDK config, %v", err)
+	}
+
+	s3Client := s3.NewFromConfig(cfg)
+
+	return &documentStore{
+		s3Client: s3Client,
+		bucket:   bucketName,
+	}
+}
+
+func (s *documentStore) FindID(ctx context.Context, id string) (*core.Document, error) {
+	resp, err := s.s3Client.GetObject(ctx, &s3.GetObjectInput{
+		Bucket: aws.String(s.bucket),
+		Key:    aws.String(id),
+	})
+	if err != nil {
+		return nil, fmt.Errorf("failed to get document with id %s: %v", id, err)
+	}
+	defer resp.Body.Close()
+
+	data, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to read document data: %v", err)
+	}
+
+	document := core.Document{
+		Data: *bytes.NewBuffer(data),
+	}
+
+	return &document, nil
+}
+
+func (s *documentStore) Create(ctx context.Context, document *core.Document) (string, error) {
+	id := ulid.Make().String()
+
+	_, err := s.s3Client.PutObject(ctx, &s3.PutObjectInput{
+		Bucket: aws.String(s.bucket),
+		Key:    aws.String(id),
+		Body:   bytes.NewReader(document.Data.Bytes()),
+	})
+	if err != nil {
+		return "", fmt.Errorf("failed to upload document: %v", err)
+	}
+
+	return id, nil
+}

stores/filesystem/documents.go

@@ -0,0 +1,54 @@
+package filesystem
+
+import (
+	"bytes"
+	"context"
+	"excalidraw-complete/core"
+	"fmt"
+	"log"
+	"os"
+	"path/filepath"
+
+	"github.com/oklog/ulid/v2"
+)
+
+type documentStore struct {
+	basePath string // Directory where documents are stored.
+}
+
+func NewDocumentStore(basePath string) core.DocumentStore {
+	if err := os.MkdirAll(basePath, 0755); err != nil {
+		log.Fatalf("failed to create base directory: %v", err)
+	}
+
+	return &documentStore{basePath: basePath}
+}
+
+func (s *documentStore) FindID(ctx context.Context, id string) (*core.Document, error) {
+	filePath := filepath.Join(s.basePath, id)
+
+	data, err := os.ReadFile(filePath)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil, fmt.Errorf("document with id %s not found", id)
+		}
+		return nil, err
+	}
+
+	document := core.Document{
+		Data: *bytes.NewBuffer(data),
+	}
+
+	return &document, nil
+}
+
+func (s *documentStore) Create(ctx context.Context, document *core.Document) (string, error) {
+	id := ulid.Make().String()
+	filePath := filepath.Join(s.basePath, id)
+
+	if err := os.WriteFile(filePath, document.Data.Bytes(), 0644); err != nil {
+		return "", err
+	}
+
+	return id, nil
+}

stores/memory/documents.go

@@ -0,0 +1,31 @@
+package memory
+
+import (
+	"context"
+	"excalidraw-complete/core"
+	"fmt"
+
+	"github.com/oklog/ulid/v2"
+)
+
+var savedDocuments = make(map[string]core.Document)
+
+type documentStore struct {
+}
+
+func NewDocumentStore() core.DocumentStore {
+	return &documentStore{}
+}
+
+func (s *documentStore) FindID(ctx context.Context, id string) (*core.Document, error) {
+	if val, ok := savedDocuments[id]; ok {
+		return &val, nil
+	}
+	return nil, fmt.Errorf("document with id %s not found", id)
+}
+
+func (s *documentStore) Create(ctx context.Context, document *core.Document) (string, error) {
+	id := ulid.Make().String()
+	savedDocuments[id] = *document
+	return id, nil
+}

stores/sqlite/documents.go

@@ -0,0 +1,60 @@
+package sqlite
+
+import (
+	"bytes"
+	"context"
+	"excalidraw-complete/core"
+	"fmt"
+
+	"database/sql"
+	"log"
+
+	_ "github.com/mattn/go-sqlite3"
+	"github.com/oklog/ulid/v2"
+)
+
+var savedDocuments = make(map[string]core.Document)
+
+type documentStore struct {
+	db *sql.DB
+}
+
+func NewDocumentStore(dataSourceName string) core.DocumentStore {
+	// db, err := sql.Open("sqlite3", ":memory:")
+	db, err := sql.Open("sqlite3", dataSourceName)
+
+	if err != nil {
+		log.Fatal(err)
+	}
+	sts := `CREATE TABLE IF NOT EXISTS documents (id TEXT PRIMARY KEY, data BLOB);`
+	_, err = db.Exec(sts)
+	if err != nil {
+		log.Fatal(err)
+	}
+	return &documentStore{db}
+}
+
+func (s *documentStore) FindID(ctx context.Context, id string) (*core.Document, error) {
+	var data []byte
+	err := s.db.QueryRowContext(ctx, "SELECT data FROM documents WHERE id = ?", id).Scan(&data)
+	if err != nil {
+		if err == sql.ErrNoRows {
+			return nil, fmt.Errorf("document with id %s not found", id)
+		}
+		return nil, err
+	}
+	document := core.Document{
+		Data: *bytes.NewBuffer(data),
+	}
+	return &document, nil
+}
+
+func (s *documentStore) Create(ctx context.Context, document *core.Document) (string, error) {
+	id := ulid.Make().String()
+	data := document.Data.Bytes()
+	_, err := s.db.ExecContext(ctx, "INSERT INTO documents (id, data) VALUES (?, ?)", id, data)
+	if err != nil {
+		return "", err
+	}
+	return id, nil
+}

stores/storage.go

@@ -0,0 +1,30 @@
+package stores
+
+import (
+	"excalidraw-complete/core"
+	"excalidraw-complete/stores/aws"
+	"excalidraw-complete/stores/filesystem"
+	"excalidraw-complete/stores/memory"
+	"excalidraw-complete/stores/sqlite"
+	"os"
+)
+
+func GetStore() core.DocumentStore {
+	storageType := os.Getenv("STORAGE_TYPE")
+	var store core.DocumentStore
+
+	switch storageType {
+	case "filesystem":
+		basePath := os.Getenv("LOCAL_STORAGE_PATH")
+		store = filesystem.NewDocumentStore(basePath)
+	case "sqlite":
+		dataSourceName := os.Getenv("DATA_SOURCE_NAME")
+		store = sqlite.NewDocumentStore(dataSourceName)
+	case "s3":
+		bucketName := os.Getenv("S3_BUCKET_NAME")
+		store = aws.NewDocumentStore(bucketName)
+	default:
+		store = memory.NewDocumentStore()
+	}
+	return store
+}