From 80f8b1b883596f69aa74ecb4839e91f477923c22 Mon Sep 17 00:00:00 2001
From: Ben McClelland <ben.mcclelland@versity.com>
Date: Wed, 17 May 2023 16:00:00 -0700
Subject: [PATCH] posix: initial bucket requests

---
 backend/common.go      | 14 +++++-
 backend/posix/posix.go | 96 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 109 insertions(+), 1 deletion(-)

diff --git a/backend/common.go b/backend/common.go
index d96432d9..080ee865 100644
--- a/backend/common.go
+++ b/backend/common.go
@@ -1,6 +1,10 @@
 package backend
 
-import "github.com/aws/aws-sdk-go-v2/service/s3/types"
+import (
+	"time"
+
+	"github.com/aws/aws-sdk-go-v2/service/s3/types"
+)
 
 func IsValidBucketName(name string) bool { return true }
 
@@ -9,3 +13,11 @@ type ByBucketName []types.Bucket
 func (d ByBucketName) Len() int           { return len(d) }
 func (d ByBucketName) Swap(i, j int)      { d[i], d[j] = d[j], d[i] }
 func (d ByBucketName) Less(i, j int) bool { return *d[i].Name < *d[j].Name }
+
+func GetStringPtr(s string) *string {
+	return &s
+}
+
+func GetTimePtr(t time.Time) *time.Time {
+	return &t
+}
diff --git a/backend/posix/posix.go b/backend/posix/posix.go
index 55af7df5..d0406a80 100644
--- a/backend/posix/posix.go
+++ b/backend/posix/posix.go
@@ -1,7 +1,16 @@
 package posix
 
 import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"sort"
+	"syscall"
+
+	"github.com/aws/aws-sdk-go-v2/service/s3"
+	"github.com/aws/aws-sdk-go-v2/service/s3/types"
 	"github.com/versity/scoutgw/backend"
+	"github.com/versity/scoutgw/s3err"
 )
 
 type Posix struct {
@@ -9,3 +18,90 @@ type Posix struct {
 }
 
 var _ backend.Backend = &Posix{}
+
+const metaTmpDir = ".sgwtmp"
+
+func (p *Posix) ListBuckets() (*s3.ListBucketsOutput, error) {
+	entries, err := os.ReadDir(".")
+	if err != nil {
+		return nil, fmt.Errorf("readdir buckets: %w", err)
+	}
+
+	var buckets []types.Bucket
+	for _, entry := range entries {
+		if !entry.IsDir() {
+			// buckets must be a directory
+			continue
+		}
+
+		fi, err := entry.Info()
+		if err != nil {
+			// skip entries returning errors
+			continue
+		}
+
+		buckets = append(buckets, types.Bucket{
+			Name:         backend.GetStringPtr(entry.Name()),
+			CreationDate: backend.GetTimePtr(fi.ModTime()),
+		})
+	}
+
+	sort.Sort(backend.ByBucketName(buckets))
+
+	return &s3.ListBucketsOutput{
+		Buckets: buckets,
+	}, nil
+}
+
+func (p *Posix) HeadBucket(bucket string) (*s3.HeadBucketOutput, error) {
+	_, err := os.Lstat(bucket)
+	if err != nil && os.IsNotExist(err) {
+		return nil, s3err.GetAPIError(s3err.ErrNoSuchBucket)
+	}
+	if err != nil {
+		return nil, fmt.Errorf("stat bucket: %w", err)
+	}
+
+	return &s3.HeadBucketOutput{}, nil
+}
+
+func (p *Posix) PutBucket(bucket string) error {
+	err := os.Mkdir(bucket, 0777)
+	if err != nil && os.IsExist(err) {
+		return s3err.GetAPIError(s3err.ErrBucketAlreadyExists)
+	}
+	if err != nil {
+		return fmt.Errorf("mkdir bucket: %w", err)
+	}
+
+	return nil
+}
+
+func (p *Posix) DeleteBucket(bucket string) error {
+	names, err := os.ReadDir(bucket)
+	if err != nil && os.IsNotExist(err) {
+		return s3err.GetAPIError(s3err.ErrNoSuchBucket)
+	}
+	if err != nil {
+		return fmt.Errorf("readdir bucket: %w", err)
+	}
+
+	if len(names) == 1 && names[0].Name() == metaTmpDir {
+		// if .sgwtmp is only item in directory
+		// then clean this up before trying to remove the bucket
+		err = os.RemoveAll(filepath.Join(bucket, metaTmpDir))
+		if err != nil && !os.IsNotExist(err) {
+			return fmt.Errorf("remove temp dir: %w", err)
+		}
+	}
+
+	err = os.Remove(bucket)
+	if err != nil && err.(*os.PathError).Err == syscall.ENOTEMPTY {
+		return s3err.GetAPIError(s3err.ErrBucketNotEmpty)
+	}
+	if err != nil {
+		return fmt.Errorf("remove bucket: %w", err)
+	}
+
+	return nil
+}