PLT-???? Prepare file upload infrastructure for Data Retention. (#7266)

* Prepare file upload infrastructure for Data Retention.

This commit prepares the file upload infrastructure for the data
retention feature that is under construction. Changes are:

* Move file management code to utils to allow access to it from jobs.

* From now on, store all file uploads in a top level folder which is the
  date of the day on which they were uploaded.

This commit is based on Harrison Healey's branch, but updated to work
with the latest master.

* Use NewAppError

20 files changed, 678 insertions, 299 deletions

diff --git a/api/emoji_test.go b/api/emoji_test.go
index 600f7975e..4de5f41dd 100644
--- a/api/emoji_test.go
+++ b/api/emoji_test.go
@@ -266,7 +266,7 @@ func TestDeleteEmoji(t *testing.T) {
 func createTestEmoji(t *testing.T, emoji *model.Emoji, imageData []byte) *model.Emoji {
 	emoji = store.Must(app.Srv.Store.Emoji().Save(emoji)).(*model.Emoji)
 
-	if err := app.WriteFile(imageData, "emoji/"+emoji.Id+"/image"); err != nil {
+	if err := utils.WriteFile(imageData, "emoji/"+emoji.Id+"/image"); err != nil {
 		store.Must(app.Srv.Store.Emoji().Delete(emoji.Id, time.Now().Unix()))
 		t.Fatalf("failed to write image: %v", err.Error())
 	}
diff --git a/api/file.go b/api/file.go
index 342430ed1..1eab30e76 100644
--- a/api/file.go
+++ b/api/file.go
@@ -96,7 +96,7 @@ func getFile(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if data, err := app.ReadFile(info.Path); err != nil {
+	if data, err := utils.ReadFile(info.Path); err != nil {
 		c.Err = err
 		c.Err.StatusCode = http.StatusNotFound
 	} else if err := writeFileResponse(info.Name, info.MimeType, data, w, r); err != nil {
@@ -118,7 +118,7 @@ func getFileThumbnail(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if data, err := app.ReadFile(info.ThumbnailPath); err != nil {
+	if data, err := utils.ReadFile(info.ThumbnailPath); err != nil {
 		c.Err = err
 		c.Err.StatusCode = http.StatusNotFound
 	} else if err := writeFileResponse(info.Name, THUMBNAIL_IMAGE_TYPE, data, w, r); err != nil {
@@ -140,7 +140,7 @@ func getFilePreview(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if data, err := app.ReadFile(info.PreviewPath); err != nil {
+	if data, err := utils.ReadFile(info.PreviewPath); err != nil {
 		c.Err = err
 		c.Err.StatusCode = http.StatusNotFound
 	} else if err := writeFileResponse(info.Name, PREVIEW_IMAGE_TYPE, data, w, r); err != nil {
@@ -190,7 +190,7 @@ func getPublicFile(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if data, err := app.ReadFile(info.Path); err != nil {
+	if data, err := utils.ReadFile(info.Path); err != nil {
 		c.Err = err
 		c.Err.StatusCode = http.StatusNotFound
 	} else if err := writeFileResponse(info.Name, info.MimeType, data, w, r); err != nil {
@@ -285,7 +285,7 @@ func getPublicFileOld(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if data, err := app.ReadFile(info.Path); err != nil {
+	if data, err := utils.ReadFile(info.Path); err != nil {
 		c.Err = err
 		c.Err.StatusCode = http.StatusNotFound
 	} else if err := writeFileResponse(info.Name, info.MimeType, data, w, r); err != nil {
diff --git a/api/file_test.go b/api/file_test.go
index 0e0a5772c..282cff2ec 100644
--- a/api/file_test.go
+++ b/api/file_test.go
@@ -81,20 +81,22 @@ func TestUploadFile(t *testing.T) {
 		t.Fatal("file preview path should be set in database")
 	}
 
+	date := time.Now().Format("20060102")
+
 	// This also makes sure that the relative path provided above is sanitized out
-	expectedPath := fmt.Sprintf("teams/%v/channels/%v/users/%v/%v/test.png", team.Id, channel.Id, user.Id, info.Id)
+	expectedPath := fmt.Sprintf("%v/teams/%v/channels/%v/users/%v/%v/test.png", date, team.Id, channel.Id, user.Id, info.Id)
 	if info.Path != expectedPath {
 		t.Logf("file is saved in %v", info.Path)
 		t.Fatalf("file should've been saved in %v", expectedPath)
 	}
 
-	expectedThumbnailPath := fmt.Sprintf("teams/%v/channels/%v/users/%v/%v/test_thumb.jpg", team.Id, channel.Id, user.Id, info.Id)
+	expectedThumbnailPath := fmt.Sprintf("%v/teams/%v/channels/%v/users/%v/%v/test_thumb.jpg", date, team.Id, channel.Id, user.Id, info.Id)
 	if info.ThumbnailPath != expectedThumbnailPath {
 		t.Logf("file thumbnail is saved in %v", info.ThumbnailPath)
 		t.Fatalf("file thumbnail should've been saved in %v", expectedThumbnailPath)
 	}
 
-	expectedPreviewPath := fmt.Sprintf("teams/%v/channels/%v/users/%v/%v/test_preview.jpg", team.Id, channel.Id, user.Id, info.Id)
+	expectedPreviewPath := fmt.Sprintf("%v/teams/%v/channels/%v/users/%v/%v/test_preview.jpg", date, team.Id, channel.Id, user.Id, info.Id)
 	if info.PreviewPath != expectedPreviewPath {
 		t.Logf("file preview is saved in %v", info.PreviewPath)
 		t.Fatalf("file preview should've been saved in %v", expectedPreviewPath)
@@ -466,7 +468,6 @@ func TestGetPublicFileOld(t *testing.T) {
 	utils.Cfg.FileSettings.EnablePublicLink = true
 	*utils.Cfg.FileSettings.PublicLinkSalt = model.NewId()
 
-	Client := th.BasicClient
 	channel := th.BasicChannel
 
 	var fileId string
@@ -474,7 +475,16 @@ func TestGetPublicFileOld(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	} else {
-		fileId = Client.MustGeneric(Client.UploadPostAttachment(data, channel.Id, "test.png")).(*model.FileUploadResponse).FileInfos[0].Id
+		//fileId = Client.MustGeneric(Client.UploadPostAttachment(data, channel.Id, "test.png")).(*model.FileUploadResponse).FileInfos[0].Id
+		fileId = model.NewId()
+		fileInfo := model.FileInfo{
+			Id:        fileId,
+			CreateAt:  model.GetMillis(),
+			CreatorId: th.BasicUser.Id,
+			Path:      fmt.Sprintf("teams/%s/channels/%s/users/%s/%s/%s", th.BasicTeam.Id, channel.Id, th.BasicUser.Id, fileId, "test.png"),
+		}
+		store.Must(app.Srv.Store.FileInfo().Save(&fileInfo))
+		uploadFileOld(t, data, fmt.Sprintf("data/teams/%s/channels/%s/users/%s/%s", th.BasicTeam.Id, channel.Id, th.BasicUser.Id, fileId), "test.png")
 	}
 
 	// Hacky way to assign file to a post (usually would be done by CreatePost call)
@@ -619,7 +629,9 @@ func TestMigrateFilenamesToFileInfos(t *testing.T) {
 		t.Fatal(err)
 	} else {
 		fileId1 = Client.MustGeneric(Client.UploadPostAttachment(data, channel1.Id, "test.png")).(*model.FileUploadResponse).FileInfos[0].Id
+		uploadFileOld(t, data, fmt.Sprintf("data/teams/%s/channels/%s/users/%s/%s", th.BasicTeam.Id, channel1.Id, user1.Id, fileId1), "test.png")
 		fileId2 = Client.MustGeneric(Client.UploadPostAttachment(data, channel1.Id, "test.png")).(*model.FileUploadResponse).FileInfos[0].Id
+		uploadFileOld(t, data, fmt.Sprintf("data/teams/%s/channels/%s/users/%s/%s", th.BasicTeam.Id, channel1.Id, user1.Id, fileId2), "test.png")
 	}
 
 	// Bypass the Client whenever possible since we're trying to simulate a pre-3.5 post
@@ -686,6 +698,25 @@ func TestMigrateFilenamesToFileInfos(t *testing.T) {
 	}
 }
 
+func uploadFileOld(t *testing.T, data []byte, dest string, filename string) {
+	os.MkdirAll(dest, os.ModePerm)
+	eFile, err := os.Create(dest + "/" + filename)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer eFile.Close()
+
+	_, err = io.Copy(eFile, bytes.NewReader(data)) // first var shows number of bytes
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	err = eFile.Sync()
+	if err != nil {
+		t.Fatal(err)
+	}
+}
+
 func TestFindTeamIdForFilename(t *testing.T) {
 	th := Setup().InitBasic()
 
@@ -717,9 +748,11 @@ func TestFindTeamIdForFilename(t *testing.T) {
 		t.Fatal(err)
 	} else {
 		fileId1 = Client.MustGeneric(Client.UploadPostAttachment(data, channel1.Id, "test.png")).(*model.FileUploadResponse).FileInfos[0].Id
+		uploadFileOld(t, data, fmt.Sprintf("data/teams/%s/channels/%s/users/%s/%s", team1.Id, channel1.Id, user1.Id, fileId1), "test.png")
 
 		Client.SetTeamId(team2.Id)
 		fileId2 = Client.MustGeneric(Client.UploadPostAttachment(data, channel2.Id, "test.png")).(*model.FileUploadResponse).FileInfos[0].Id
+		uploadFileOld(t, data, fmt.Sprintf("data/teams/%s/channels/%s/users/%s/%s", team2.Id, channel2.Id, user1.Id, fileId2), "test.png")
 		Client.SetTeamId(team1.Id)
 	}
 
@@ -732,6 +765,7 @@ func TestFindTeamIdForFilename(t *testing.T) {
 	})).(*model.Post)
 
 	if teamId := app.FindTeamIdForFilename(post1, post1.Filenames[0]); teamId != team1.Id {
+		t.Log(teamId)
 		t.Fatal("file should've been found under team1")
 	}
 
@@ -773,6 +807,7 @@ func TestGetInfoForFilename(t *testing.T) {
 		t.Fatal(err)
 	} else {
 		fileId1 = Client.MustGeneric(Client.UploadPostAttachment(data, channel1.Id, "test.png")).(*model.FileUploadResponse).FileInfos[0].Id
+		uploadFileOld(t, data, fmt.Sprintf("data/teams/%s/channels/%s/users/%s/%s", team1.Id, channel1.Id, user1.Id, fileId1), "test.png")
 		path = store.Must(app.Srv.Store.FileInfo().Get(fileId1)).(*model.FileInfo).Path
 		thumbnailPath = store.Must(app.Srv.Store.FileInfo().Get(fileId1)).(*model.FileInfo).ThumbnailPath
 		previewPath = store.Must(app.Srv.Store.FileInfo().Get(fileId1)).(*model.FileInfo).PreviewPath
@@ -786,6 +821,8 @@ func TestGetInfoForFilename(t *testing.T) {
 		Filenames: []string{fmt.Sprintf("/%s/%s/%s/%s", channel1.Id, user1.Id, fileId1, "test.png")},
 	})).(*model.Post)
 
+	date := time.Now().Format("20060102")
+
 	if info := app.GetInfoForFilename(post1, team1.Id, post1.Filenames[0]); info == nil {
 		t.Fatal("info shouldn't be nil")
 	} else if info.Id == "" {
@@ -794,11 +831,11 @@ func TestGetInfoForFilename(t *testing.T) {
 		t.Fatal("incorrect user id")
 	} else if info.PostId != post1.Id {
 		t.Fatal("incorrect user id")
-	} else if info.Path != path {
+	} else if fmt.Sprintf("%s/%s", date, info.Path) != path {
 		t.Fatal("incorrect path")
-	} else if info.ThumbnailPath != thumbnailPath {
+	} else if fmt.Sprintf("%s/%s", date, info.ThumbnailPath) != thumbnailPath {
 		t.Fatal("incorrect thumbnail path")
-	} else if info.PreviewPath != previewPath {
+	} else if fmt.Sprintf("%s/%s", date, info.PreviewPath) != previewPath {
 		t.Fatal("incorrect preview path")
 	} else if info.Name != "test.png" {
 		t.Fatal("incorrect name")
diff --git a/api4/file.go b/api4/file.go
index 0607c1942..7dc13dafc 100644
--- a/api4/file.go
+++ b/api4/file.go
@@ -123,7 +123,7 @@ func getFile(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	data, err := app.ReadFile(info.Path)
+	data, err := utils.ReadFile(info.Path)
 	if err != nil {
 		c.Err = err
 		c.Err.StatusCode = http.StatusNotFound
@@ -165,7 +165,7 @@ func getFileThumbnail(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if data, err := app.ReadFile(info.ThumbnailPath); err != nil {
+	if data, err := utils.ReadFile(info.ThumbnailPath); err != nil {
 		c.Err = err
 		c.Err.StatusCode = http.StatusNotFound
 	} else if err := writeFileResponse(info.Name, THUMBNAIL_IMAGE_TYPE, data, forceDownload, w, r); err != nil {
@@ -237,7 +237,7 @@ func getFilePreview(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if data, err := app.ReadFile(info.PreviewPath); err != nil {
+	if data, err := utils.ReadFile(info.PreviewPath); err != nil {
 		c.Err = err
 		c.Err.StatusCode = http.StatusNotFound
 	} else if err := writeFileResponse(info.Name, PREVIEW_IMAGE_TYPE, data, forceDownload, w, r); err != nil {
@@ -299,7 +299,7 @@ func getPublicFile(c *Context, w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	if data, err := app.ReadFile(info.Path); err != nil {
+	if data, err := utils.ReadFile(info.Path); err != nil {
 		c.Err = err
 		c.Err.StatusCode = http.StatusNotFound
 	} else if err := writeFileResponse(info.Name, info.MimeType, data, true, w, r); err != nil {
diff --git a/api4/file_test.go b/api4/file_test.go
index c2bc926e1..a2673dc8e 100644
--- a/api4/file_test.go
+++ b/api4/file_test.go
@@ -71,20 +71,22 @@ func TestUploadFile(t *testing.T) {
 		t.Fatal("file preview path should be set in database")
 	}
 
+	date := time.Now().Format("20060102")
+
 	// This also makes sure that the relative path provided above is sanitized out
-	expectedPath := fmt.Sprintf("teams/%v/channels/%v/users/%v/%v/test.png", FILE_TEAM_ID, channel.Id, user.Id, info.Id)
+	expectedPath := fmt.Sprintf("%v/teams/%v/channels/%v/users/%v/%v/test.png", date, FILE_TEAM_ID, channel.Id, user.Id, info.Id)
 	if info.Path != expectedPath {
 		t.Logf("file is saved in %v", info.Path)
 		t.Fatalf("file should've been saved in %v", expectedPath)
 	}
 
-	expectedThumbnailPath := fmt.Sprintf("teams/%v/channels/%v/users/%v/%v/test_thumb.jpg", FILE_TEAM_ID, channel.Id, user.Id, info.Id)
+	expectedThumbnailPath := fmt.Sprintf("%v/teams/%v/channels/%v/users/%v/%v/test_thumb.jpg", date, FILE_TEAM_ID, channel.Id, user.Id, info.Id)
 	if info.ThumbnailPath != expectedThumbnailPath {
 		t.Logf("file thumbnail is saved in %v", info.ThumbnailPath)
 		t.Fatalf("file thumbnail should've been saved in %v", expectedThumbnailPath)
 	}
 
-	expectedPreviewPath := fmt.Sprintf("teams/%v/channels/%v/users/%v/%v/test_preview.jpg", FILE_TEAM_ID, channel.Id, user.Id, info.Id)
+	expectedPreviewPath := fmt.Sprintf("%v/teams/%v/channels/%v/users/%v/%v/test_preview.jpg", date, FILE_TEAM_ID, channel.Id, user.Id, info.Id)
 	if info.PreviewPath != expectedPreviewPath {
 		t.Logf("file preview is saved in %v", info.PreviewPath)
 		t.Fatalf("file preview should've been saved in %v", expectedPreviewPath)
diff --git a/app/emoji.go b/app/emoji.go
index f1362b798..e01ca97ae 100644
--- a/app/emoji.go
+++ b/app/emoji.go
@@ -101,7 +101,7 @@ func UploadEmojiImage(id string, imageData *multipart.FileHeader) *model.AppErro
 				if err := gif.EncodeAll(newbuf, resized_gif); err != nil {
 					return model.NewAppError("uploadEmojiImage", "api.emoji.upload.large_image.gif_encode_error", nil, "", http.StatusBadRequest)
 				}
-				if err := WriteFile(newbuf.Bytes(), getEmojiImagePath(id)); err != nil {
+				if err := utils.WriteFile(newbuf.Bytes(), getEmojiImagePath(id)); err != nil {
 					return err
 				}
 			}
@@ -113,13 +113,13 @@ func UploadEmojiImage(id string, imageData *multipart.FileHeader) *model.AppErro
 				if err := png.Encode(newbuf, resized_image); err != nil {
 					return model.NewAppError("uploadEmojiImage", "api.emoji.upload.large_image.encode_error", nil, "", http.StatusBadRequest)
 				}
-				if err := WriteFile(newbuf.Bytes(), getEmojiImagePath(id)); err != nil {
+				if err := utils.WriteFile(newbuf.Bytes(), getEmojiImagePath(id)); err != nil {
 					return err
 				}
 			}
 		}
 	} else {
-		if err := WriteFile(buf.Bytes(), getEmojiImagePath(id)); err != nil {
+		if err := utils.WriteFile(buf.Bytes(), getEmojiImagePath(id)); err != nil {
 			return err
 		}
 	}
@@ -159,7 +159,7 @@ func GetEmojiImage(emojiId string) (imageByte []byte, imageType string, err *mod
 	} else {
 		var img []byte
 
-		if data, err := ReadFile(getEmojiImagePath(emojiId)); err != nil {
+		if data, err := utils.ReadFile(getEmojiImagePath(emojiId)); err != nil {
 			return nil, "", model.NewAppError("getEmojiImage", "api.emoji.get_image.read.app_error", nil, err.Error(), http.StatusNotFound)
 		} else {
 			img = data
@@ -219,7 +219,7 @@ func imageToPaletted(img image.Image) *image.Paletted {
 }
 
 func deleteEmojiImage(id string) {
-	if err := MoveFile(getEmojiImagePath(id), "emoji/"+id+"/image_deleted"); err != nil {
+	if err := utils.MoveFile(getEmojiImagePath(id), "emoji/"+id+"/image_deleted"); err != nil {
 		l4g.Error("Failed to rename image when deleting emoji %v", id)
 	}
 }
diff --git a/app/file.go b/app/file.go
index dc7caff41..10fb1425c 100644
--- a/app/file.go
+++ b/app/file.go
@@ -14,23 +14,21 @@ import (
 	_ "image/gif"
 	"image/jpeg"
 	"io"
-	"io/ioutil"
 	"mime/multipart"
 	"net/http"
 	"net/url"
-	"os"
 	"path/filepath"
 	"strings"
 	"sync"
+	"time"
 
 	l4g "github.com/alecthomas/log4go"
 	"github.com/disintegration/imaging"
-	"github.com/mattermost/platform/model"
-	"github.com/mattermost/platform/utils"
-	s3 "github.com/minio/minio-go"
-	"github.com/minio/minio-go/pkg/credentials"
 	"github.com/rwcarlsen/goexif/exif"
 	_ "golang.org/x/image/bmp"
+
+	"github.com/mattermost/platform/model"
+	"github.com/mattermost/platform/utils"
 )
 
 const (
@@ -57,222 +55,8 @@ const (
 	IMAGE_THUMBNAIL_PIXEL_WIDTH  = 120
 	IMAGE_THUMBNAIL_PIXEL_HEIGHT = 100
 	IMAGE_PREVIEW_PIXEL_WIDTH    = 1024
-
-	TEST_FILE_PATH = "/testfile"
 )
 
-// Similar to s3.New() but allows initialization of signature v2 or signature v4 client.
-// If signV2 input is false, function always returns signature v4.
-//
-// Additionally this function also takes a user defined region, if set
-// disables automatic region lookup.
-func s3New(endpoint, accessKey, secretKey string, secure bool, signV2 bool, region string) (*s3.Client, error) {
-	var creds *credentials.Credentials
-	if signV2 {
-		creds = credentials.NewStatic(accessKey, secretKey, "", credentials.SignatureV2)
-	} else {
-		creds = credentials.NewStatic(accessKey, secretKey, "", credentials.SignatureV4)
-	}
-	return s3.NewWithCredentials(endpoint, creds, secure, region)
-}
-
-func TestFileConnection() *model.AppError {
-	if utils.Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_S3 {
-		endpoint := utils.Cfg.FileSettings.AmazonS3Endpoint
-		accessKey := utils.Cfg.FileSettings.AmazonS3AccessKeyId
-		secretKey := utils.Cfg.FileSettings.AmazonS3SecretAccessKey
-		secure := *utils.Cfg.FileSettings.AmazonS3SSL
-		signV2 := *utils.Cfg.FileSettings.AmazonS3SignV2
-		region := utils.Cfg.FileSettings.AmazonS3Region
-		bucket := utils.Cfg.FileSettings.AmazonS3Bucket
-
-		s3Clnt, err := s3New(endpoint, accessKey, secretKey, secure, signV2, region)
-		if err != nil {
-			return model.NewLocAppError("TestFileConnection", "Bad connection to S3 or minio.", nil, err.Error())
-		}
-
-		exists, err := s3Clnt.BucketExists(bucket)
-		if err != nil {
-			return model.NewLocAppError("TestFileConnection", "Error checking if bucket exists.", nil, err.Error())
-		}
-
-		if !exists {
-			l4g.Warn("Bucket specified does not exist. Attempting to create...")
-			err := s3Clnt.MakeBucket(bucket, region)
-			if err != nil {
-				l4g.Error("Unable to create bucket.")
-				return model.NewAppError("TestFileConnection", "Unable to create bucket", nil, err.Error(), http.StatusInternalServerError)
-			}
-		}
-		l4g.Info("Connection to S3 or minio is good. Bucket exists.")
-	} else if utils.Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_LOCAL {
-		f := []byte("testingwrite")
-		if err := writeFileLocally(f, utils.Cfg.FileSettings.Directory+TEST_FILE_PATH); err != nil {
-			return model.NewAppError("TestFileConnection", "Don't have permissions to write to local path specified or other error.", nil, err.Error(), http.StatusInternalServerError)
-		}
-		os.Remove(utils.Cfg.FileSettings.Directory + TEST_FILE_PATH)
-		l4g.Info("Able to write files to local storage.")
-	} else {
-		return model.NewLocAppError("TestFileConnection", "No file driver selected.", nil, "")
-	}
-
-	return nil
-}
-
-func ReadFile(path string) ([]byte, *model.AppError) {
-	if utils.Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_S3 {
-		endpoint := utils.Cfg.FileSettings.AmazonS3Endpoint
-		accessKey := utils.Cfg.FileSettings.AmazonS3AccessKeyId
-		secretKey := utils.Cfg.FileSettings.AmazonS3SecretAccessKey
-		secure := *utils.Cfg.FileSettings.AmazonS3SSL
-		signV2 := *utils.Cfg.FileSettings.AmazonS3SignV2
-		region := utils.Cfg.FileSettings.AmazonS3Region
-		s3Clnt, err := s3New(endpoint, accessKey, secretKey, secure, signV2, region)
-		if err != nil {
-			return nil, model.NewLocAppError("ReadFile", "api.file.read_file.s3.app_error", nil, err.Error())
-		}
-		bucket := utils.Cfg.FileSettings.AmazonS3Bucket
-		minioObject, err := s3Clnt.GetObject(bucket, path)
-		defer minioObject.Close()
-		if err != nil {
-			return nil, model.NewLocAppError("ReadFile", "api.file.read_file.s3.app_error", nil, err.Error())
-		}
-		if f, err := ioutil.ReadAll(minioObject); err != nil {
-			return nil, model.NewLocAppError("ReadFile", "api.file.read_file.s3.app_error", nil, err.Error())
-		} else {
-			return f, nil
-		}
-	} else if utils.Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_LOCAL {
-		if f, err := ioutil.ReadFile(utils.Cfg.FileSettings.Directory + path); err != nil {
-			return nil, model.NewLocAppError("ReadFile", "api.file.read_file.reading_local.app_error", nil, err.Error())
-		} else {
-			return f, nil
-		}
-	} else {
-		return nil, model.NewAppError("ReadFile", "api.file.read_file.configured.app_error", nil, "", http.StatusNotImplemented)
-	}
-}
-
-func MoveFile(oldPath, newPath string) *model.AppError {
-	if utils.Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_S3 {
-		endpoint := utils.Cfg.FileSettings.AmazonS3Endpoint
-		accessKey := utils.Cfg.FileSettings.AmazonS3AccessKeyId
-		secretKey := utils.Cfg.FileSettings.AmazonS3SecretAccessKey
-		secure := *utils.Cfg.FileSettings.AmazonS3SSL
-		signV2 := *utils.Cfg.FileSettings.AmazonS3SignV2
-		region := utils.Cfg.FileSettings.AmazonS3Region
-		encrypt := false
-		if *utils.Cfg.FileSettings.AmazonS3SSE && utils.IsLicensed() && *utils.License().Features.Compliance {
-			encrypt = true
-		}
-		s3Clnt, err := s3New(endpoint, accessKey, secretKey, secure, signV2, region)
-		if err != nil {
-			return model.NewLocAppError("moveFile", "api.file.write_file.s3.app_error", nil, err.Error())
-		}
-		bucket := utils.Cfg.FileSettings.AmazonS3Bucket
-
-		source := s3.NewSourceInfo(bucket, oldPath, nil)
-		destination, err := s3.NewDestinationInfo(bucket, newPath, nil, CopyMetadata(encrypt))
-		if err != nil {
-			return model.NewLocAppError("moveFile", "api.file.write_file.s3.app_error", nil, err.Error())
-		}
-		if err = s3Clnt.CopyObject(destination, source); err != nil {
-			return model.NewLocAppError("moveFile", "api.file.move_file.delete_from_s3.app_error", nil, err.Error())
-		}
-		if err = s3Clnt.RemoveObject(bucket, oldPath); err != nil {
-			return model.NewLocAppError("moveFile", "api.file.move_file.delete_from_s3.app_error", nil, err.Error())
-		}
-	} else if utils.Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_LOCAL {
-		if err := os.MkdirAll(filepath.Dir(utils.Cfg.FileSettings.Directory+newPath), 0774); err != nil {
-			return model.NewLocAppError("moveFile", "api.file.move_file.rename.app_error", nil, err.Error())
-		}
-
-		if err := os.Rename(utils.Cfg.FileSettings.Directory+oldPath, utils.Cfg.FileSettings.Directory+newPath); err != nil {
-			return model.NewLocAppError("moveFile", "api.file.move_file.rename.app_error", nil, err.Error())
-		}
-	} else {
-		return model.NewLocAppError("moveFile", "api.file.move_file.configured.app_error", nil, "")
-	}
-
-	return nil
-}
-
-func WriteFile(f []byte, path string) *model.AppError {
-	if utils.Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_S3 {
-		endpoint := utils.Cfg.FileSettings.AmazonS3Endpoint
-		accessKey := utils.Cfg.FileSettings.AmazonS3AccessKeyId
-		secretKey := utils.Cfg.FileSettings.AmazonS3SecretAccessKey
-		secure := *utils.Cfg.FileSettings.AmazonS3SSL
-		signV2 := *utils.Cfg.FileSettings.AmazonS3SignV2
-		region := utils.Cfg.FileSettings.AmazonS3Region
-		encrypt := false
-		if *utils.Cfg.FileSettings.AmazonS3SSE && utils.IsLicensed() && *utils.License().Features.Compliance {
-			encrypt = true
-		}
-
-		s3Clnt, err := s3New(endpoint, accessKey, secretKey, secure, signV2, region)
-		if err != nil {
-			return model.NewLocAppError("WriteFile", "api.file.write_file.s3.app_error", nil, err.Error())
-		}
-
-		bucket := utils.Cfg.FileSettings.AmazonS3Bucket
-		ext := filepath.Ext(path)
-		metaData := S3Metadata(encrypt, "binary/octet-stream")
-		if model.IsFileExtImage(ext) {
-			metaData = S3Metadata(encrypt, model.GetImageMimeType(ext))
-		}
-
-		_, err = s3Clnt.PutObjectWithMetadata(bucket, path, bytes.NewReader(f), metaData, nil)
-		if err != nil {
-			return model.NewLocAppError("WriteFile", "api.file.write_file.s3.app_error", nil, err.Error())
-		}
-	} else if utils.Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_LOCAL {
-		if err := writeFileLocally(f, utils.Cfg.FileSettings.Directory+path); err != nil {
-			return err
-		}
-	} else {
-		return model.NewLocAppError("WriteFile", "api.file.write_file.configured.app_error", nil, "")
-	}
-
-	return nil
-}
-
-func writeFileLocally(f []byte, path string) *model.AppError {
-	if err := os.MkdirAll(filepath.Dir(path), 0774); err != nil {
-		directory, _ := filepath.Abs(filepath.Dir(path))
-		return model.NewLocAppError("WriteFile", "api.file.write_file_locally.create_dir.app_error", nil, "directory="+directory+", err="+err.Error())
-	}
-
-	if err := ioutil.WriteFile(path, f, 0644); err != nil {
-		return model.NewLocAppError("WriteFile", "api.file.write_file_locally.writing.app_error", nil, err.Error())
-	}
-
-	return nil
-}
-
-func openFileWriteStream(path string) (io.Writer, *model.AppError) {
-	if utils.Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_S3 {
-		return nil, model.NewLocAppError("openFileWriteStream", "api.file.open_file_write_stream.s3.app_error", nil, "")
-	} else if utils.Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_LOCAL {
-		if err := os.MkdirAll(filepath.Dir(utils.Cfg.FileSettings.Directory+path), 0774); err != nil {
-			return nil, model.NewLocAppError("openFileWriteStream", "api.file.open_file_write_stream.creating_dir.app_error", nil, err.Error())
-		}
-
-		if fileHandle, err := os.Create(utils.Cfg.FileSettings.Directory + path); err != nil {
-			return nil, model.NewLocAppError("openFileWriteStream", "api.file.open_file_write_stream.local_server.app_error", nil, err.Error())
-		} else {
-			fileHandle.Chmod(0644)
-			return fileHandle, nil
-		}
-	}
-
-	return nil, model.NewLocAppError("openFileWriteStream", "api.file.open_file_write_stream.configured.app_error", nil, "")
-}
-
-func closeFileWriteStream(file io.Writer) {
-	file.(*os.File).Close()
-}
-
 func GetInfoForFilename(post *model.Post, teamId string, filename string) *model.FileInfo {
 	// Find the path from the Filename of the form /{channelId}/{userId}/{uid}/{nameWithExtension}
 	split := strings.SplitN(filename, "/", 5)
@@ -295,7 +79,7 @@ func GetInfoForFilename(post *model.Post, teamId string, filename string) *model
 
 	// Open the file and populate the fields of the FileInfo
 	var info *model.FileInfo
-	if data, err := ReadFile(path); err != nil {
+	if data, err := utils.ReadFile(path); err != nil {
 		l4g.Error(utils.T("api.file.migrate_filenames_to_file_infos.file_not_found.error"), post.Id, filename, path, err)
 		return nil
 	} else {
@@ -337,7 +121,7 @@ func FindTeamIdForFilename(post *model.Post, filename string) string {
 	} else {
 		for _, team := range teams {
 			path := fmt.Sprintf("teams/%s/channels/%s/users/%s/%s/%s", team.Id, post.ChannelId, post.UserId, id, name)
-			if _, err := ReadFile(path); err == nil {
+			if _, err := utils.ReadFile(path); err == nil {
 				// Found the team that this file was posted from
 				return team.Id
 			}
@@ -484,7 +268,7 @@ func UploadFiles(teamId string, channelId string, userId string, fileHeaders []*
 		io.Copy(buf, file)
 		data := buf.Bytes()
 
-		info, err := DoUploadFile(teamId, channelId, userId, fileHeader.Filename, data)
+		info, err := DoUploadFile(time.Now(), teamId, channelId, userId, fileHeader.Filename, data)
 		if err != nil {
 			return nil, err
 		}
@@ -507,7 +291,7 @@ func UploadFiles(teamId string, channelId string, userId string, fileHeaders []*
 	return resStruct, nil
 }
 
-func DoUploadFile(teamId string, channelId string, userId string, rawFilename string, data []byte) (*model.FileInfo, *model.AppError) {
+func DoUploadFile(now time.Time, teamId string, channelId string, userId string, rawFilename string, data []byte) (*model.FileInfo, *model.AppError) {
 	filename := filepath.Base(rawFilename)
 
 	info, err := model.GetInfoForBytes(filename, data)
@@ -519,7 +303,7 @@ func DoUploadFile(teamId string, channelId string, userId string, rawFilename st
 	info.Id = model.NewId()
 	info.CreatorId = userId
 
-	pathPrefix := "teams/" + teamId + "/channels/" + channelId + "/users/" + userId + "/" + info.Id + "/"
+	pathPrefix := now.Format("20060102") + "/teams/" + teamId + "/channels/" + channelId + "/users/" + userId + "/" + info.Id + "/"
 	info.Path = pathPrefix + filename
 
 	if info.IsImage() {
@@ -535,7 +319,7 @@ func DoUploadFile(teamId string, channelId string, userId string, rawFilename st
 		info.ThumbnailPath = pathPrefix + nameWithoutExtension + "_thumb.jpg"
 	}
 
-	if err := WriteFile(data, info.Path); err != nil {
+	if err := utils.WriteFile(data, info.Path); err != nil {
 		return nil, err
 	}
 
@@ -652,7 +436,7 @@ func generateThumbnailImage(img image.Image, thumbnailPath string, width int, he
 		return
 	}
 
-	if err := WriteFile(buf.Bytes(), thumbnailPath); err != nil {
+	if err := utils.WriteFile(buf.Bytes(), thumbnailPath); err != nil {
 		l4g.Error(utils.T("api.file.handle_images_forget.upload_thumb.error"), thumbnailPath, err)
 		return
 	}
@@ -674,7 +458,7 @@ func generatePreviewImage(img image.Image, previewPath string, width int) {
 		return
 	}
 
-	if err := WriteFile(buf.Bytes(), previewPath); err != nil {
+	if err := utils.WriteFile(buf.Bytes(), previewPath); err != nil {
 		l4g.Error(utils.T("api.file.handle_images_forget.upload_preview.error"), previewPath, err)
 		return
 	}
@@ -687,20 +471,3 @@ func GetFileInfo(fileId string) (*model.FileInfo, *model.AppError) {
 		return result.Data.(*model.FileInfo), nil
 	}
 }
-
-func S3Metadata(encrypt bool, contentType string) map[string][]string {
-	metaData := make(map[string][]string)
-	if contentType != "" {
-		metaData["Content-Type"] = []string{"contentType"}
-	}
-	if encrypt {
-		metaData["x-amz-server-side-encryption"] = []string{"AES256"}
-	}
-	return metaData
-}
-
-func CopyMetadata(encrypt bool) map[string]string {
-	metaData := make(map[string]string)
-	metaData["x-amz-server-side-encryption"] = "AES256"
-	return metaData
-}
diff --git a/app/file_test.go b/app/file_test.go
index 683b574b8..962661039 100644
--- a/app/file_test.go
+++ b/app/file_test.go
@@ -4,9 +4,12 @@
 package app
 
 import (
+	"fmt"
 	"testing"
+	"time"
 
 	"github.com/mattermost/platform/model"
+	"github.com/mattermost/platform/utils"
 )
 
 func TestGeneratePublicLinkHash(t *testing.T) {
@@ -31,3 +34,55 @@ func TestGeneratePublicLinkHash(t *testing.T) {
 		t.Fatal("hashes for the same file with different salts should not be equal")
 	}
 }
+
+func TestDoUploadFile(t *testing.T) {
+	Setup()
+
+	teamId := model.NewId()
+	channelId := model.NewId()
+	userId := model.NewId()
+	filename := "test"
+	data := []byte("abcd")
+
+	info1, err := DoUploadFile(time.Date(2007, 2, 4, 1, 2, 3, 4, time.Local), teamId, channelId, userId, filename, data)
+	if err != nil {
+		t.Fatal(err)
+	} else {
+		defer func() {
+			<-Srv.Store.FileInfo().PermanentDelete(info1.Id)
+			utils.RemoveFile(info1.Path)
+		}()
+	}
+
+	if info1.Path != fmt.Sprintf("20070204/teams/%v/channels/%v/users/%v/%v/%v", teamId, channelId, userId, info1.Id, filename) {
+		t.Fatal("stored file at incorrect path", info1.Path)
+	}
+
+	info2, err := DoUploadFile(time.Date(2007, 2, 4, 1, 2, 3, 4, time.Local), teamId, channelId, userId, filename, data)
+	if err != nil {
+		t.Fatal(err)
+	} else {
+		defer func() {
+			<-Srv.Store.FileInfo().PermanentDelete(info2.Id)
+			utils.RemoveFile(info2.Path)
+		}()
+	}
+
+	if info2.Path != fmt.Sprintf("20070204/teams/%v/channels/%v/users/%v/%v/%v", teamId, channelId, userId, info2.Id, filename) {
+		t.Fatal("stored file at incorrect path", info2.Path)
+	}
+
+	info3, err := DoUploadFile(time.Date(2008, 3, 5, 1, 2, 3, 4, time.Local), teamId, channelId, userId, filename, data)
+	if err != nil {
+		t.Fatal(err)
+	} else {
+		defer func() {
+			<-Srv.Store.FileInfo().PermanentDelete(info3.Id)
+			utils.RemoveFile(info3.Path)
+		}()
+	}
+
+	if info3.Path != fmt.Sprintf("20080305/teams/%v/channels/%v/users/%v/%v/%v", teamId, channelId, userId, info3.Id, filename) {
+		t.Fatal("stored file at incorrect path", info3.Path)
+	}
+}
diff --git a/app/import.go b/app/import.go
index fb7d43cdf..d404dbadd 100644
--- a/app/import.go
+++ b/app/import.go
@@ -12,9 +12,11 @@ import (
 	"regexp"
 	"strings"
 	"sync"
+	"time"
 	"unicode/utf8"
 
 	l4g "github.com/alecthomas/log4go"
+
 	"github.com/mattermost/platform/model"
 	"github.com/mattermost/platform/store"
 	"github.com/mattermost/platform/utils"
@@ -1486,12 +1488,12 @@ func OldImportChannel(channel *model.Channel) *model.Channel {
 	}
 }
 
-func OldImportFile(file io.Reader, teamId string, channelId string, userId string, fileName string) (*model.FileInfo, error) {
+func OldImportFile(timestamp time.Time, file io.Reader, teamId string, channelId string, userId string, fileName string) (*model.FileInfo, error) {
 	buf := bytes.NewBuffer(nil)
 	io.Copy(buf, file)
 	data := buf.Bytes()
 
-	fileInfo, err := DoUploadFile(teamId, channelId, userId, fileName, data)
+	fileInfo, err := DoUploadFile(timestamp, teamId, channelId, userId, fileName, data)
 	if err != nil {
 		return nil, err
 	}
diff --git a/app/slackimport.go b/app/slackimport.go
index 4470b8323..e57a3a3d1 100644
--- a/app/slackimport.go
+++ b/app/slackimport.go
@@ -401,7 +401,8 @@ func SlackUploadFile(sPost SlackPost, uploads map[string]*zip.File, teamId strin
 			}
 			defer openFile.Close()
 
-			uploadedFile, err := OldImportFile(openFile, teamId, channelId, userId, filepath.Base(file.Name))
+			timestamp := utils.TimeFromMillis(SlackConvertTimeStamp(sPost.TimeStamp))
+			uploadedFile, err := OldImportFile(timestamp, openFile, teamId, channelId, userId, filepath.Base(file.Name))
 			if err != nil {
 				l4g.Warn(utils.T("api.slackimport.slack_add_posts.upload_file_upload_failed.warn", map[string]interface{}{"FileId": sPost.File.Id, "Error": err.Error()}))
 				return nil, false
diff --git a/app/user.go b/app/user.go
index 813421a5c..40e32c282 100644
--- a/app/user.go
+++ b/app/user.go
@@ -758,7 +758,7 @@ func GetProfileImage(user *model.User) ([]byte, bool, *model.AppError) {
 	} else {
 		path := "users/" + user.Id + "/profile.png"
 
-		if data, err := ReadFile(path); err != nil {
+		if data, err := utils.ReadFile(path); err != nil {
 			readFailed = true
 
 			if img, err = CreateProfileImage(user.Username, user.Id); err != nil {
@@ -766,7 +766,7 @@ func GetProfileImage(user *model.User) ([]byte, bool, *model.AppError) {
 			}
 
 			if user.LastPictureUpdate == 0 {
-				if err := WriteFile(img, path); err != nil {
+				if err := utils.WriteFile(img, path); err != nil {
 					return nil, false, err
 				}
 			}
@@ -819,7 +819,7 @@ func SetProfileImage(userId string, imageData *multipart.FileHeader) *model.AppE
 
 	path := "users/" + userId + "/profile.png"
 
-	if err := WriteFile(buf.Bytes(), path); err != nil {
+	if err := utils.WriteFile(buf.Bytes(), path); err != nil {
 		return model.NewLocAppError("SetProfileImage", "api.user.upload_profile_user.upload_profile.app_error", nil, "")
 	}
 
diff --git a/cmd/platform/server.go b/cmd/platform/server.go
index ac8f3baff..f5be5a5fc 100644
--- a/cmd/platform/server.go
+++ b/cmd/platform/server.go
@@ -67,7 +67,7 @@ func runServer(configFileLocation string) {
 		*utils.Cfg.ServiceSettings.EnableDeveloper = true
 	}
 
-	if err := app.TestFileConnection(); err != nil {
+	if err := utils.TestFileConnection(); err != nil {
 		l4g.Error("Problem with file storage settings: " + err.Error())
 	}
 
diff --git a/i18n/en.json b/i18n/en.json
index 900a6865f..338eba46e 100644
--- a/i18n/en.json
+++ b/i18n/en.json
@@ -1234,32 +1234,40 @@
     "translation": "Unable to move file locally."
   },
   {
-    "id": "api.file.open_file_write_stream.configured.app_error",
+    "id": "api.file.read_file.configured.app_error",
     "translation": "File storage not configured properly. Please configure for either S3 or local server file storage."
   },
   {
-    "id": "api.file.open_file_write_stream.creating_dir.app_error",
-    "translation": "Encountered an error creating the directory for the new file"
+    "id": "api.file.read_file.get.app_error",
+    "translation": "Unable to get file from S3"
   },
   {
-    "id": "api.file.open_file_write_stream.local_server.app_error",
-    "translation": "Encountered an error writing to local server storage"
+    "id": "api.file.read_file.reading_local.app_error",
+    "translation": "Encountered an error reading from local server storage"
   },
   {
-    "id": "api.file.open_file_write_stream.s3.app_error",
-    "translation": "S3 is not supported."
+    "id": "utils.file.remove_file.local.app_error",
+    "translation": "Encountered an error removing file from local server file storage."
   },
   {
-    "id": "api.file.read_file.configured.app_error",
+    "id": "utils.file.remove_file.s3.app_error",
+    "translation": "Encountered an error removing file from S3."
+  },
+  {
+    "id": "utils.file.remove_file.configured.app_error",
     "translation": "File storage not configured properly. Please configure for either S3 or local server file storage."
   },
   {
-    "id": "api.file.read_file.get.app_error",
-    "translation": "Unable to get file from S3"
+    "id": "utils.file.remove_directory.local.app_error",
+    "translation": "Encountered an error removing directory from local server file storage."
   },
   {
-    "id": "api.file.read_file.reading_local.app_error",
-    "translation": "Encountered an error reading from local server storage"
+    "id": "utils.file.remove_directory.s3.app_error",
+    "translation": "Encountered an error removing directory from S3."
+  },
+  {
+    "id": "utils.file.remove_directory.configured.app_error",
+    "translation": "File storage not configured properly. Please configure for either S3 or local server file storage."
   },
   {
     "id": "api.file.upload_file.bad_parse.app_error",
@@ -5576,6 +5584,10 @@
     "translation": "We couldn't save or update the file info"
   },
   {
+    "id": "store.sql_file_info.permanent_delete.app_error",
+    "translation": "We couldn't permanently delete the file info"
+  },
+  {
     "id": "store.sql_job.delete.app_error",
     "translation": "We couldn't delete the job"
   },
diff --git a/model/file_info.go b/model/file_info.go
index 8b5684127..3071e6d4b 100644
--- a/model/file_info.go
+++ b/model/file_info.go
@@ -80,6 +80,9 @@ func (o *FileInfo) PreSave() {
 
 	if o.CreateAt == 0 {
 		o.CreateAt = GetMillis()
+	}
+
+	if o.UpdateAt < o.CreateAt {
 		o.UpdateAt = o.CreateAt
 	}
 }
diff --git a/store/sql_file_info_store.go b/store/sql_file_info_store.go
index 3fe62121c..4bf6c9c73 100644
--- a/store/sql_file_info_store.go
+++ b/store/sql_file_info_store.go
@@ -97,7 +97,7 @@ func (fs SqlFileInfoStore) Get(id string) StoreChannel {
 			if err == sql.ErrNoRows {
 				result.Err = model.NewAppError("SqlFileInfoStore.Get", "store.sql_file_info.get.app_error", nil, "id="+id+", "+err.Error(), http.StatusNotFound)
 			} else {
-				result.Err = model.NewLocAppError("SqlFileInfoStore.Get", "store.sql_file_info.get.app_error", nil, "id="+id+", "+err.Error())
+				result.Err = model.NewAppError("SqlFileInfoStore.Get", "store.sql_file_info.get.app_error", nil, "id="+id+", "+err.Error(), http.StatusInternalServerError)
 			}
 		} else {
 			result.Data = info
@@ -127,7 +127,7 @@ func (fs SqlFileInfoStore) GetByPath(path string) StoreChannel {
 				Path = :Path
 				AND DeleteAt = 0
 			LIMIT 1`, map[string]interface{}{"Path": path}); err != nil {
-			result.Err = model.NewLocAppError("SqlFileInfoStore.GetByPath", "store.sql_file_info.get_by_path.app_error", nil, "path="+path+", "+err.Error())
+			result.Err = model.NewAppError("SqlFileInfoStore.GetByPath", "store.sql_file_info.get_by_path.app_error", nil, "path="+path+", "+err.Error(), http.StatusInternalServerError)
 		} else {
 			result.Data = info
 		}
@@ -139,7 +139,7 @@ func (fs SqlFileInfoStore) GetByPath(path string) StoreChannel {
 	return storeChannel
 }
 
-func (s SqlFileInfoStore) InvalidateFileInfosForPostCache(postId string) {
+func (fs SqlFileInfoStore) InvalidateFileInfosForPostCache(postId string) {
 	fileInfoCache.Remove(postId)
 }
 
@@ -190,8 +190,8 @@ func (fs SqlFileInfoStore) GetForPost(postId string, readFromMaster bool, allowF
 				AND DeleteAt = 0
 			ORDER BY
 				CreateAt`, map[string]interface{}{"PostId": postId}); err != nil {
-			result.Err = model.NewLocAppError("SqlFileInfoStore.GetForPost",
-				"store.sql_file_info.get_for_post.app_error", nil, "post_id="+postId+", "+err.Error())
+			result.Err = model.NewAppError("SqlFileInfoStore.GetForPost",
+				"store.sql_file_info.get_for_post.app_error", nil, "post_id="+postId+", "+err.Error(), http.StatusInternalServerError)
 		} else {
 			if len(infos) > 0 {
 				fileInfoCache.AddWithExpiresInSecs(postId, infos, FILE_INFO_CACHE_SEC)
@@ -221,8 +221,8 @@ func (fs SqlFileInfoStore) AttachToPost(fileId, postId string) StoreChannel {
 				WHERE
 					Id = :Id
 					AND PostId = ''`, map[string]interface{}{"PostId": postId, "Id": fileId}); err != nil {
-			result.Err = model.NewLocAppError("SqlFileInfoStore.AttachToPost",
-				"store.sql_file_info.attach_to_post.app_error", nil, "post_id="+postId+", file_id="+fileId+", err="+err.Error())
+			result.Err = model.NewAppError("SqlFileInfoStore.AttachToPost",
+				"store.sql_file_info.attach_to_post.app_error", nil, "post_id="+postId+", file_id="+fileId+", err="+err.Error(), http.StatusInternalServerError)
 		}
 
 		storeChannel <- result
@@ -245,8 +245,8 @@ func (fs SqlFileInfoStore) DeleteForPost(postId string) StoreChannel {
 				DeleteAt = :DeleteAt
 			WHERE
 				PostId = :PostId`, map[string]interface{}{"DeleteAt": model.GetMillis(), "PostId": postId}); err != nil {
-			result.Err = model.NewLocAppError("SqlFileInfoStore.DeleteForPost",
-				"store.sql_file_info.delete_for_post.app_error", nil, "post_id="+postId+", err="+err.Error())
+			result.Err = model.NewAppError("SqlFileInfoStore.DeleteForPost",
+				"store.sql_file_info.delete_for_post.app_error", nil, "post_id="+postId+", err="+err.Error(), http.StatusInternalServerError)
 		} else {
 			result.Data = postId
 		}
@@ -257,3 +257,25 @@ func (fs SqlFileInfoStore) DeleteForPost(postId string) StoreChannel {
 
 	return storeChannel
 }
+
+func (fs SqlFileInfoStore) PermanentDelete(fileId string) StoreChannel {
+	storeChannel := make(StoreChannel, 1)
+
+	go func() {
+		result := StoreResult{}
+
+		if _, err := fs.GetMaster().Exec(
+			`DELETE FROM
+				FileInfo
+			WHERE
+				Id = :FileId`, map[string]interface{}{"FileId": fileId}); err != nil {
+			result.Err = model.NewAppError("SqlFileInfoStore.PermanentDelete",
+				"store.sql_file_info.permanent_delete.app_error", nil, "file_id="+fileId+", err="+err.Error(), http.StatusInternalServerError)
+		}
+
+		storeChannel <- result
+		close(storeChannel)
+	}()
+
+	return storeChannel
+}
diff --git a/store/sql_file_info_store_test.go b/store/sql_file_info_store_test.go
index daec06269..fecd862c0 100644
--- a/store/sql_file_info_store_test.go
+++ b/store/sql_file_info_store_test.go
@@ -25,6 +25,9 @@ func TestFileInfoSaveGet(t *testing.T) {
 	} else {
 		info = returned
 	}
+	defer func() {
+		<-store.FileInfo().PermanentDelete(info.Id)
+	}()
 
 	if result := <-store.FileInfo().Get(info.Id); result.Err != nil {
 		t.Fatal(result.Err)
@@ -43,6 +46,9 @@ func TestFileInfoSaveGet(t *testing.T) {
 	if result := <-store.FileInfo().Get(info2.Id); result.Err == nil {
 		t.Fatal("shouldn't have gotten deleted file")
 	}
+	defer func() {
+		<-store.FileInfo().PermanentDelete(info2.Id)
+	}()
 }
 
 func TestFileInfoSaveGetByPath(t *testing.T) {
@@ -60,6 +66,9 @@ func TestFileInfoSaveGetByPath(t *testing.T) {
 	} else {
 		info = returned
 	}
+	defer func() {
+		<-store.FileInfo().PermanentDelete(info.Id)
+	}()
 
 	if result := <-store.FileInfo().GetByPath(info.Path); result.Err != nil {
 		t.Fatal(result.Err)
@@ -78,6 +87,9 @@ func TestFileInfoSaveGetByPath(t *testing.T) {
 	if result := <-store.FileInfo().GetByPath(info2.Id); result.Err == nil {
 		t.Fatal("shouldn't have gotten deleted file")
 	}
+	defer func() {
+		<-store.FileInfo().PermanentDelete(info2.Id)
+	}()
 }
 
 func TestFileInfoGetForPost(t *testing.T) {
@@ -112,6 +124,9 @@ func TestFileInfoGetForPost(t *testing.T) {
 
 	for i, info := range infos {
 		infos[i] = Must(store.FileInfo().Save(info)).(*model.FileInfo)
+		defer func(id string) {
+			<-store.FileInfo().PermanentDelete(id)
+		}(infos[i].Id)
 	}
 
 	if result := <-store.FileInfo().GetForPost(postId, true, false); result.Err != nil {
@@ -143,6 +158,9 @@ func TestFileInfoAttachToPost(t *testing.T) {
 		CreatorId: userId,
 		Path:      "file.txt",
 	})).(*model.FileInfo)
+	defer func() {
+		<-store.FileInfo().PermanentDelete(info1.Id)
+	}()
 
 	if len(info1.PostId) != 0 {
 		t.Fatal("file shouldn't have a PostId")
@@ -162,6 +180,9 @@ func TestFileInfoAttachToPost(t *testing.T) {
 		CreatorId: userId,
 		Path:      "file.txt",
 	})).(*model.FileInfo)
+	defer func() {
+		<-store.FileInfo().PermanentDelete(info2.Id)
+	}()
 
 	if result := <-store.FileInfo().AttachToPost(info2.Id, postId); result.Err != nil {
 		t.Fatal(result.Err)
@@ -208,6 +229,9 @@ func TestFileInfoDeleteForPost(t *testing.T) {
 
 	for i, info := range infos {
 		infos[i] = Must(store.FileInfo().Save(info)).(*model.FileInfo)
+		defer func(id string) {
+			<-store.FileInfo().PermanentDelete(id)
+		}(infos[i].Id)
 	}
 
 	if result := <-store.FileInfo().DeleteForPost(postId); result.Err != nil {
@@ -218,3 +242,17 @@ func TestFileInfoDeleteForPost(t *testing.T) {
 		t.Fatal("shouldn't have returned any file infos")
 	}
 }
+
+func TestFileInfoPermanentDelete(t *testing.T) {
+	Setup()
+
+	info := Must(store.FileInfo().Save(&model.FileInfo{
+		PostId:    model.NewId(),
+		CreatorId: model.NewId(),
+		Path:      "file.txt",
+	})).(*model.FileInfo)
+
+	if result := <-store.FileInfo().PermanentDelete(info.Id); result.Err != nil {
+		t.Fatal(result.Err)
+	}
+}
diff --git a/store/store.go b/store/store.go
index e86b5f116..0aa4d5c41 100644
--- a/store/store.go
+++ b/store/store.go
@@ -386,6 +386,7 @@ type FileInfoStore interface {
 	InvalidateFileInfosForPostCache(postId string)
 	AttachToPost(fileId string, postId string) StoreChannel
 	DeleteForPost(postId string) StoreChannel
+	PermanentDelete(fileId string) StoreChannel
 }
 
 type ReactionStore interface {
diff --git a/utils/file.go b/utils/file.go
new file mode 100644
index 000000000..efed1e954
--- /dev/null
+++ b/utils/file.go
@@ -0,0 +1,313 @@
+// Copyright (c) 2017-present Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package utils
+
+import (
+	"bytes"
+	"io/ioutil"
+	"net/http"
+	"os"
+	"path/filepath"
+
+	l4g "github.com/alecthomas/log4go"
+	s3 "github.com/minio/minio-go"
+	"github.com/minio/minio-go/pkg/credentials"
+
+	"github.com/mattermost/platform/model"
+)
+
+const (
+	TEST_FILE_PATH = "/testfile"
+)
+
+// Similar to s3.New() but allows initialization of signature v2 or signature v4 client.
+// If signV2 input is false, function always returns signature v4.
+//
+// Additionally this function also takes a user defined region, if set
+// disables automatic region lookup.
+func s3New(endpoint, accessKey, secretKey string, secure bool, signV2 bool, region string) (*s3.Client, error) {
+	var creds *credentials.Credentials
+	if signV2 {
+		creds = credentials.NewStatic(accessKey, secretKey, "", credentials.SignatureV2)
+	} else {
+		creds = credentials.NewStatic(accessKey, secretKey, "", credentials.SignatureV4)
+	}
+	return s3.NewWithCredentials(endpoint, creds, secure, region)
+}
+
+func TestFileConnection() *model.AppError {
+	if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_S3 {
+		endpoint := Cfg.FileSettings.AmazonS3Endpoint
+		accessKey := Cfg.FileSettings.AmazonS3AccessKeyId
+		secretKey := Cfg.FileSettings.AmazonS3SecretAccessKey
+		secure := *Cfg.FileSettings.AmazonS3SSL
+		signV2 := *Cfg.FileSettings.AmazonS3SignV2
+		region := Cfg.FileSettings.AmazonS3Region
+		bucket := Cfg.FileSettings.AmazonS3Bucket
+
+		s3Clnt, err := s3New(endpoint, accessKey, secretKey, secure, signV2, region)
+		if err != nil {
+			return model.NewLocAppError("TestFileConnection", "Bad connection to S3 or minio.", nil, err.Error())
+		}
+
+		exists, err := s3Clnt.BucketExists(bucket)
+		if err != nil {
+			return model.NewLocAppError("TestFileConnection", "Error checking if bucket exists.", nil, err.Error())
+		}
+
+		if !exists {
+			l4g.Warn("Bucket specified does not exist. Attempting to create...")
+			err := s3Clnt.MakeBucket(bucket, region)
+			if err != nil {
+				l4g.Error("Unable to create bucket.")
+				return model.NewAppError("TestFileConnection", "Unable to create bucket", nil, err.Error(), http.StatusInternalServerError)
+			}
+		}
+		l4g.Info("Connection to S3 or minio is good. Bucket exists.")
+	} else if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_LOCAL {
+		f := []byte("testingwrite")
+		if err := writeFileLocally(f, Cfg.FileSettings.Directory+TEST_FILE_PATH); err != nil {
+			return model.NewAppError("TestFileConnection", "Don't have permissions to write to local path specified or other error.", nil, err.Error(), http.StatusInternalServerError)
+		}
+		os.Remove(Cfg.FileSettings.Directory + TEST_FILE_PATH)
+		l4g.Info("Able to write files to local storage.")
+	} else {
+		return model.NewLocAppError("TestFileConnection", "No file driver selected.", nil, "")
+	}
+
+	return nil
+}
+
+func ReadFile(path string) ([]byte, *model.AppError) {
+	if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_S3 {
+		endpoint := Cfg.FileSettings.AmazonS3Endpoint
+		accessKey := Cfg.FileSettings.AmazonS3AccessKeyId
+		secretKey := Cfg.FileSettings.AmazonS3SecretAccessKey
+		secure := *Cfg.FileSettings.AmazonS3SSL
+		signV2 := *Cfg.FileSettings.AmazonS3SignV2
+		region := Cfg.FileSettings.AmazonS3Region
+		s3Clnt, err := s3New(endpoint, accessKey, secretKey, secure, signV2, region)
+		if err != nil {
+			return nil, model.NewLocAppError("ReadFile", "api.file.read_file.s3.app_error", nil, err.Error())
+		}
+		bucket := Cfg.FileSettings.AmazonS3Bucket
+		minioObject, err := s3Clnt.GetObject(bucket, path)
+		defer minioObject.Close()
+		if err != nil {
+			return nil, model.NewLocAppError("ReadFile", "api.file.read_file.s3.app_error", nil, err.Error())
+		}
+		if f, err := ioutil.ReadAll(minioObject); err != nil {
+			return nil, model.NewLocAppError("ReadFile", "api.file.read_file.s3.app_error", nil, err.Error())
+		} else {
+			return f, nil
+		}
+	} else if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_LOCAL {
+		if f, err := ioutil.ReadFile(Cfg.FileSettings.Directory + path); err != nil {
+			return nil, model.NewLocAppError("ReadFile", "api.file.read_file.reading_local.app_error", nil, err.Error())
+		} else {
+			return f, nil
+		}
+	} else {
+		return nil, model.NewAppError("ReadFile", "api.file.read_file.configured.app_error", nil, "", http.StatusNotImplemented)
+	}
+}
+
+func MoveFile(oldPath, newPath string) *model.AppError {
+	if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_S3 {
+		endpoint := Cfg.FileSettings.AmazonS3Endpoint
+		accessKey := Cfg.FileSettings.AmazonS3AccessKeyId
+		secretKey := Cfg.FileSettings.AmazonS3SecretAccessKey
+		secure := *Cfg.FileSettings.AmazonS3SSL
+		signV2 := *Cfg.FileSettings.AmazonS3SignV2
+		region := Cfg.FileSettings.AmazonS3Region
+		encrypt := false
+		if *Cfg.FileSettings.AmazonS3SSE && IsLicensed() && *License().Features.Compliance {
+			encrypt = true
+		}
+		s3Clnt, err := s3New(endpoint, accessKey, secretKey, secure, signV2, region)
+		if err != nil {
+			return model.NewLocAppError("moveFile", "api.file.write_file.s3.app_error", nil, err.Error())
+		}
+		bucket := Cfg.FileSettings.AmazonS3Bucket
+
+		source := s3.NewSourceInfo(bucket, oldPath, nil)
+		destination, err := s3.NewDestinationInfo(bucket, newPath, nil, CopyMetadata(encrypt))
+		if err != nil {
+			return model.NewLocAppError("moveFile", "api.file.write_file.s3.app_error", nil, err.Error())
+		}
+		if err = s3Clnt.CopyObject(destination, source); err != nil {
+			return model.NewLocAppError("moveFile", "api.file.move_file.delete_from_s3.app_error", nil, err.Error())
+		}
+		if err = s3Clnt.RemoveObject(bucket, oldPath); err != nil {
+			return model.NewLocAppError("moveFile", "api.file.move_file.delete_from_s3.app_error", nil, err.Error())
+		}
+	} else if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_LOCAL {
+		if err := os.MkdirAll(filepath.Dir(Cfg.FileSettings.Directory+newPath), 0774); err != nil {
+			return model.NewLocAppError("moveFile", "api.file.move_file.rename.app_error", nil, err.Error())
+		}
+
+		if err := os.Rename(Cfg.FileSettings.Directory+oldPath, Cfg.FileSettings.Directory+newPath); err != nil {
+			return model.NewLocAppError("moveFile", "api.file.move_file.rename.app_error", nil, err.Error())
+		}
+	} else {
+		return model.NewLocAppError("moveFile", "api.file.move_file.configured.app_error", nil, "")
+	}
+
+	return nil
+}
+
+func WriteFile(f []byte, path string) *model.AppError {
+	if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_S3 {
+		endpoint := Cfg.FileSettings.AmazonS3Endpoint
+		accessKey := Cfg.FileSettings.AmazonS3AccessKeyId
+		secretKey := Cfg.FileSettings.AmazonS3SecretAccessKey
+		secure := *Cfg.FileSettings.AmazonS3SSL
+		signV2 := *Cfg.FileSettings.AmazonS3SignV2
+		region := Cfg.FileSettings.AmazonS3Region
+		encrypt := false
+		if *Cfg.FileSettings.AmazonS3SSE && IsLicensed() && *License().Features.Compliance {
+			encrypt = true
+		}
+
+		s3Clnt, err := s3New(endpoint, accessKey, secretKey, secure, signV2, region)
+		if err != nil {
+			return model.NewLocAppError("WriteFile", "api.file.write_file.s3.app_error", nil, err.Error())
+		}
+
+		bucket := Cfg.FileSettings.AmazonS3Bucket
+		ext := filepath.Ext(path)
+		metaData := S3Metadata(encrypt, "binary/octet-stream")
+		if model.IsFileExtImage(ext) {
+			metaData = S3Metadata(encrypt, model.GetImageMimeType(ext))
+		}
+
+		_, err = s3Clnt.PutObjectWithMetadata(bucket, path, bytes.NewReader(f), metaData, nil)
+		if err != nil {
+			return model.NewLocAppError("WriteFile", "api.file.write_file.s3.app_error", nil, err.Error())
+		}
+	} else if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_LOCAL {
+		if err := writeFileLocally(f, Cfg.FileSettings.Directory+path); err != nil {
+			return err
+		}
+	} else {
+		return model.NewLocAppError("WriteFile", "api.file.write_file.configured.app_error", nil, "")
+	}
+
+	return nil
+}
+
+func writeFileLocally(f []byte, path string) *model.AppError {
+	if err := os.MkdirAll(filepath.Dir(path), 0774); err != nil {
+		directory, _ := filepath.Abs(filepath.Dir(path))
+		return model.NewLocAppError("WriteFile", "api.file.write_file_locally.create_dir.app_error", nil, "directory="+directory+", err="+err.Error())
+	}
+
+	if err := ioutil.WriteFile(path, f, 0644); err != nil {
+		return model.NewLocAppError("WriteFile", "api.file.write_file_locally.writing.app_error", nil, err.Error())
+	}
+
+	return nil
+}
+
+func RemoveFile(path string) *model.AppError {
+	if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_S3 {
+		endpoint := Cfg.FileSettings.AmazonS3Endpoint
+		accessKey := Cfg.FileSettings.AmazonS3AccessKeyId
+		secretKey := Cfg.FileSettings.AmazonS3SecretAccessKey
+		secure := *Cfg.FileSettings.AmazonS3SSL
+		signV2 := *Cfg.FileSettings.AmazonS3SignV2
+		region := Cfg.FileSettings.AmazonS3Region
+
+		s3Clnt, err := s3New(endpoint, accessKey, secretKey, secure, signV2, region)
+		if err != nil {
+			return model.NewLocAppError("RemoveFile", "utils.file.remove_file.s3.app_error", nil, err.Error())
+		}
+
+		bucket := Cfg.FileSettings.AmazonS3Bucket
+		if err := s3Clnt.RemoveObject(bucket, path); err != nil {
+			return model.NewLocAppError("RemoveFile", "utils.file.remove_file.s3.app_error", nil, err.Error())
+		}
+	} else if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_LOCAL {
+		if err := os.Remove(Cfg.FileSettings.Directory + path); err != nil {
+			return model.NewLocAppError("RemoveFile", "utils.file.remove_file.local.app_error", nil, err.Error())
+		}
+	} else {
+		return model.NewLocAppError("RemoveFile", "utils.file.remove_file.configured.app_error", nil, "")
+	}
+
+	return nil
+}
+
+func getPathsFromObjectInfos(in <-chan s3.ObjectInfo) <-chan string {
+	out := make(chan string, 1)
+
+	go func() {
+		defer close(out)
+
+		for {
+			info, done := <-in
+
+			if !done {
+				break
+			}
+
+			out <- info.Key
+		}
+	}()
+
+	return out
+}
+
+func RemoveDirectory(path string) *model.AppError {
+	if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_S3 {
+		endpoint := Cfg.FileSettings.AmazonS3Endpoint
+		accessKey := Cfg.FileSettings.AmazonS3AccessKeyId
+		secretKey := Cfg.FileSettings.AmazonS3SecretAccessKey
+		secure := *Cfg.FileSettings.AmazonS3SSL
+		signV2 := *Cfg.FileSettings.AmazonS3SignV2
+		region := Cfg.FileSettings.AmazonS3Region
+
+		s3Clnt, err := s3New(endpoint, accessKey, secretKey, secure, signV2, region)
+		if err != nil {
+			return model.NewLocAppError("RemoveDirectory", "utils.file.remove_directory.s3.app_error", nil, err.Error())
+		}
+
+		doneCh := make(chan struct{})
+
+		bucket := Cfg.FileSettings.AmazonS3Bucket
+		for err := range s3Clnt.RemoveObjects(bucket, getPathsFromObjectInfos(s3Clnt.ListObjects(bucket, path, true, doneCh))) {
+			if err.Err != nil {
+				doneCh <- struct{}{}
+				return model.NewLocAppError("RemoveDirectory", "utils.file.remove_directory.s3.app_error", nil, err.Err.Error())
+			}
+		}
+
+		close(doneCh)
+	} else if Cfg.FileSettings.DriverName == model.IMAGE_DRIVER_LOCAL {
+		if err := os.RemoveAll(Cfg.FileSettings.Directory + path); err != nil {
+			return model.NewLocAppError("RemoveDirectory", "utils.file.remove_directory.local.app_error", nil, err.Error())
+		}
+	} else {
+		return model.NewLocAppError("RemoveDirectory", "utils.file.remove_directory.configured.app_error", nil, "")
+	}
+
+	return nil
+}
+
+func S3Metadata(encrypt bool, contentType string) map[string][]string {
+	metaData := make(map[string][]string)
+	if contentType != "" {
+		metaData["Content-Type"] = []string{"contentType"}
+	}
+	if encrypt {
+		metaData["x-amz-server-side-encryption"] = []string{"AES256"}
+	}
+	return metaData
+}
+
+func CopyMetadata(encrypt bool) map[string]string {
+	metaData := make(map[string]string)
+	metaData["x-amz-server-side-encryption"] = "AES256"
+	return metaData
+}
diff --git a/utils/file_test.go b/utils/file_test.go
new file mode 100644
index 000000000..202a5354e
--- /dev/null
+++ b/utils/file_test.go
@@ -0,0 +1,122 @@
+// Copyright (c) 2017-present Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package utils
+
+import (
+	"testing"
+
+	"github.com/mattermost/platform/model"
+)
+
+func TestReadWriteFile(t *testing.T) {
+	TranslationsPreInit()
+	LoadConfig("config.json")
+	InitTranslations(Cfg.LocalizationSettings)
+
+	b := []byte("test")
+	path := "tests/" + model.NewId()
+
+	if err := WriteFile(b, path); err != nil {
+		t.Fatal(err)
+	}
+	defer RemoveFile(path)
+
+	if read, err := ReadFile(path); err != nil {
+		t.Fatal(err)
+	} else if readString := string(read); readString != "test" {
+		t.Fatal("should've read back contents of file")
+	}
+}
+
+func TestMoveFile(t *testing.T) {
+	TranslationsPreInit()
+	LoadConfig("config.json")
+	InitTranslations(Cfg.LocalizationSettings)
+
+	b := []byte("test")
+	path1 := "tests/" + model.NewId()
+	path2 := "tests/" + model.NewId()
+
+	if err := WriteFile(b, path1); err != nil {
+		t.Fatal(err)
+	}
+	defer RemoveFile(path1)
+
+	if err := MoveFile(path1, path2); err != nil {
+		t.Fatal(err)
+	}
+	defer RemoveFile(path2)
+
+	if _, err := ReadFile(path1); err == nil {
+		t.Fatal("file should no longer exist at old path")
+	}
+
+	if _, err := ReadFile(path2); err != nil {
+		t.Fatal("file should exist at new path", err)
+	}
+}
+
+func TestRemoveFile(t *testing.T) {
+	TranslationsPreInit()
+	LoadConfig("config.json")
+	InitTranslations(Cfg.LocalizationSettings)
+
+	b := []byte("test")
+	path := "tests/" + model.NewId()
+
+	if err := WriteFile(b, path); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := RemoveFile(path); err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err := ReadFile(path); err == nil {
+		t.Fatal("should've removed file")
+	}
+
+	if err := WriteFile(b, "tests2/foo"); err != nil {
+		t.Fatal(err)
+	}
+	if err := WriteFile(b, "tests2/bar"); err != nil {
+		t.Fatal(err)
+	}
+	if err := WriteFile(b, "tests2/asdf"); err != nil {
+		t.Fatal(err)
+	}
+	if err := RemoveDirectory("tests2"); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestRemoveDirectory(t *testing.T) {
+	TranslationsPreInit()
+	LoadConfig("config.json")
+	InitTranslations(Cfg.LocalizationSettings)
+
+	b := []byte("test")
+
+	if err := WriteFile(b, "tests2/foo"); err != nil {
+		t.Fatal(err)
+	}
+	if err := WriteFile(b, "tests2/bar"); err != nil {
+		t.Fatal(err)
+	}
+	if err := WriteFile(b, "tests2/aaa"); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := RemoveDirectory("tests2"); err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err := ReadFile("tests2/foo"); err == nil {
+		t.Fatal("should've removed file")
+	} else if _, err := ReadFile("tests2/bar"); err == nil {
+		t.Fatal("should've removed file")
+	} else if _, err := ReadFile("tests2/asdf"); err == nil {
+		t.Fatal("should've removed file")
+	}
+}
diff --git a/utils/time.go b/utils/time.go
index 7d5afdf8f..baddd7329 100644
--- a/utils/time.go
+++ b/utils/time.go
@@ -8,6 +8,10 @@ func MillisFromTime(t time.Time) int64 {
 	return t.UnixNano() / int64(time.Millisecond)
 }
 
+func TimeFromMillis(millis int64) time.Time {
+	return time.Unix(0, millis*int64(time.Millisecond))
+}
+
 func StartOfDay(t time.Time) time.Time {
 	year, month, day := t.Date()
 	return time.Date(year, month, day, 0, 0, 0, 0, t.Location())