simplify IO by using only internal buffers

Author: theandrew168

README.md

@@ -48,7 +48,7 @@ This key is intentionally absent from pg2s3's environment in order to require us
 
 | Variable                  | Description |
 | ------------------------- | ----------- |
-| `PG2S3_AGE_PUBLIC_KEY`    | Public key generated by [age](https://github.com/FiloSottile/age) |
+| `PG2S3_AGE_PUBLIC_KEY`    | Public key for backup encryption |
 
 ## Usage
 The pg2s3 command-line tool offers three commands:

cmd/cli/main.go

@@ -9,40 +9,44 @@ import (
 	"strconv"
 	"strings"
 
+	"filippo.io/age"
 	"github.com/theandrew168/pg2s3"
 	"golang.org/x/term"
 )
 
-// TODO: move env var names to package constants?
-
 func main() {
 	log.SetFlags(0)
 
+	usage := "usage: pg2s3 backup|restore|prune"
+	if len(os.Args) < 2 {
+		log.Fatalln(usage)
+	}
+
 	client, err := pg2s3.New(
-		requireEnv("PG2S3_PG_CONNECTION_URI"),
-		requireEnv("PG2S3_S3_ENDPOINT"),
-		requireEnv("PG2S3_S3_ACCESS_KEY_ID"),
-		requireEnv("PG2S3_S3_SECRET_ACCESS_KEY"),
-		requireEnv("PG2S3_S3_BUCKET_NAME"))
+		requireEnv(pg2s3.EnvPGConnectionURI),
+		requireEnv(pg2s3.EnvS3Endpoint),
+		requireEnv(pg2s3.EnvS3AccessKeyID),
+		requireEnv(pg2s3.EnvS3SecretAccessKey),
+		requireEnv(pg2s3.EnvS3BucketName))
 	if err != nil {
 		log.Fatalln(err)
 	}
 
-	prefix := requireEnv("PG2S3_BACKUP_PREFIX")
-	retention, err := strconv.Atoi(requireEnv("PG2S3_BACKUP_RETENTION"))
+	prefix := requireEnv(pg2s3.EnvBackupPrefix)
+	retention, err := strconv.Atoi(requireEnv(pg2s3.EnvBackupRetention))
 	if err != nil {
 		log.Fatalln(err)
 	}
 
-	usage := "usage: pg2s3 backup|restore|prune"
-	if len(os.Args) < 2 {
-		log.Fatalln(usage)
+	// validate public key (if provided)
+	publicKey := os.Getenv(pg2s3.EnvAgePublicKey)
+	if publicKey != "" {
+		_, err = age.ParseX25519Recipient(publicKey)
+		if err != nil {
+			log.Fatalln(err)
+		}
 	}
 
-	// TODO: verify connection to PG
-	// TODO: verify connection to S3
-	// TODO: verify age public key (if provided)
-
 	cmd := os.Args[1]
 	switch cmd {
 	case "backup":
@@ -91,39 +95,32 @@ func confirm(message string) bool {
 }
 
 func backup(client *pg2s3.Client, prefix string) error {
-	publicKey := os.Getenv("PG2S3_AGE_PUBLIC_KEY")
+	publicKey := os.Getenv(pg2s3.EnvAgePublicKey)
 
 	// generate name for backup
 	name, err := pg2s3.GenerateBackupName(prefix)
 	if err != nil {
 		return err
 	}
 
-	// generate path for backup
-	path := pg2s3.GenerateBackupPath(name)
-
 	// create backup
-	err = client.CreateBackup(path)
+	backup, err := client.CreateBackup()
 	if err != nil {
 		return err
 	}
-	defer os.Remove(path)
 
 	// encrypt backup (if applicable)
 	if publicKey != "" {
-		agePath := path + ".age"
-		err := client.EncryptBackup(agePath, path, publicKey)
+		backup, err = client.EncryptBackup(backup, publicKey)
 		if err != nil {
 			return err
 		}
 
 		name = name + ".age"
-		path = agePath
 	}
-	defer os.Remove(path)
 
 	// upload backup
-	err = client.UploadBackup(name, path)
+	err = client.UploadBackup(name, backup)
 	if err != nil {
 		return err
 	}
@@ -133,7 +130,7 @@ func backup(client *pg2s3.Client, prefix string) error {
 }
 
 func restore(client *pg2s3.Client) error {
-	publicKey := os.Getenv("PG2S3_AGE_PUBLIC_KEY")
+	publicKey := os.Getenv(pg2s3.EnvAgePublicKey)
 
 	// list all backups
 	backups, err := client.ListBackups()
@@ -148,34 +145,28 @@ func restore(client *pg2s3.Client) error {
 	// determine latest backup
 	latest := backups[0]
 
-	// generate path for backup
-	path := pg2s3.GenerateBackupPath(latest)
-
 	// download backup
-	err = client.DownloadBackup(path, latest)
+	backup, err := client.DownloadBackup(latest)
 	if err != nil {
 		return err
 	}
-	defer os.Remove(path)
 
 	// decrypt backup (if applicable)
 	if publicKey != "" {
-		fmt.Println("enter age private key:")
+		fmt.Print("enter private key: ")
 		input, err := term.ReadPassword(int(os.Stdin.Fd()))
 		if err != nil {
 			return err
 		}
 
+		fmt.Println()
 		privateKey := string(input)
 
-		agePath := path
-		path = strings.TrimSuffix(path, ".age")
-		err = client.DecryptBackup(path, agePath, privateKey)
+		backup, err = client.DecryptBackup(backup, privateKey)
 		if err != nil {
 			return err
 		}
 	}
-	defer os.Remove(path)
 
 	// confirm restore before applying
 	message := fmt.Sprintf("restore %s", latest)
@@ -184,7 +175,7 @@ func restore(client *pg2s3.Client) error {
 	}
 
 	// restore backup
-	err = client.RestoreBackup(path)
+	err = client.RestoreBackup(backup)
 	if err != nil {
 		return err
 	}

go.mod

@@ -4,13 +4,21 @@ go 1.17
 
 require (
 	filippo.io/age v1.0.0
+	github.com/jackc/pgx/v4 v4.13.0
 	github.com/minio/minio-go/v7 v7.0.14
 	golang.org/x/term v0.0.0-20210615171337-6886f2dfbf5b
 )
 
 require (
 	github.com/dustin/go-humanize v1.0.0 // indirect
 	github.com/google/uuid v1.1.1 // indirect
+	github.com/jackc/chunkreader/v2 v2.0.1 // indirect
+	github.com/jackc/pgconn v1.10.0 // indirect
+	github.com/jackc/pgio v1.0.0 // indirect
+	github.com/jackc/pgpassfile v1.0.0 // indirect
+	github.com/jackc/pgproto3/v2 v2.1.1 // indirect
+	github.com/jackc/pgservicefile v0.0.0-20200714003250-2b9c44734f2b // indirect
+	github.com/jackc/pgtype v1.8.1 // indirect
 	github.com/json-iterator/go v1.1.10 // indirect
 	github.com/klauspost/cpuid v1.3.1 // indirect
 	github.com/minio/md5-simd v1.1.0 // indirect
@@ -23,6 +31,6 @@ require (
 	golang.org/x/crypto v0.0.0-20210817164053-32db794688a5 // indirect
 	golang.org/x/net v0.0.0-20210226172049-e18ecbb05110 // indirect
 	golang.org/x/sys v0.0.0-20210903071746-97244b99971b // indirect
-	golang.org/x/text v0.3.3 // indirect
+	golang.org/x/text v0.3.6 // indirect
 	gopkg.in/ini.v1 v1.57.0 // indirect
 )