From 43bf1072077e1f452d64c8852b368975928d212f Mon Sep 17 00:00:00 2001
From: David Christofas <dchristofas@owncloud.com>
Date: Sat, 21 Mar 2020 18:50:18 +0100
Subject: [PATCH 1/8] implement a resolution handler

---
 pkg/thumbnails/resolution/resolution.go       | 37 ++++++++
 pkg/thumbnails/resolution/resolution_test.go  | 26 ++++++
 pkg/thumbnails/resolution/resolutions.go      | 58 ++++++++++++
 pkg/thumbnails/resolution/resolutions_test.go | 91 +++++++++++++++++++
 4 files changed, 212 insertions(+)
 create mode 100644 pkg/thumbnails/resolution/resolution.go
 create mode 100644 pkg/thumbnails/resolution/resolution_test.go
 create mode 100644 pkg/thumbnails/resolution/resolutions.go
 create mode 100644 pkg/thumbnails/resolution/resolutions_test.go

diff --git a/pkg/thumbnails/resolution/resolution.go b/pkg/thumbnails/resolution/resolution.go
new file mode 100644
index 0000000000..514fe85744
--- /dev/null
+++ b/pkg/thumbnails/resolution/resolution.go
@@ -0,0 +1,37 @@
+package resolution
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// Parse parses a resolution string in the form <width>x<height> and returns a resolution instance.
+func Parse(s string) (Resolution, error) {
+	parts := strings.Split(s, "x")
+	if len(parts) != 2 {
+		return Resolution{}, fmt.Errorf("failed to parse resolution: %s. Expected format <width>x<height>", s)
+	}
+	width, err := strconv.Atoi(parts[0])
+	if err != nil {
+		return Resolution{}, fmt.Errorf("width: %s has an invalid value. Expected an integer", parts[0])
+	}
+	height, err := strconv.Atoi(parts[1])
+	if err != nil {
+		return Resolution{}, fmt.Errorf("height: %s has an invalid value. Expected an integer", parts[1])
+	}
+	return Resolution{Width: width, Height: height}, nil
+}
+
+// Resolution defines represents the width and height of a thumbnail.
+type Resolution struct {
+	Width  int
+	Height int
+}
+
+// String returns the resolution in the format:
+//
+// <width>x<height>
+func (r Resolution) String() string {
+	return strconv.Itoa(r.Width) + "x" + strconv.Itoa(r.Height)
+}
diff --git a/pkg/thumbnails/resolution/resolution_test.go b/pkg/thumbnails/resolution/resolution_test.go
new file mode 100644
index 0000000000..18d6e46764
--- /dev/null
+++ b/pkg/thumbnails/resolution/resolution_test.go
@@ -0,0 +1,26 @@
+package resolution
+
+import "testing"
+
+func TestParseWithEmptyString(t *testing.T) {
+	_, err := Parse("")
+	if err == nil {
+		t.Error("Parse with empty string should return an error.")
+	}
+}
+
+func TestParse(t *testing.T) {
+	rStr := "42x23"
+	r, _ := Parse(rStr)
+	if r.Width != 42 || r.Height != 23 {
+		t.Errorf("Expected resolution %s got %s", rStr, r.String())
+	}
+}
+
+func TestString(t *testing.T) {
+	r := Resolution{Width: 42, Height: 23}
+	expected := "42x23"
+	if r.String() != expected {
+		t.Errorf("Expected string %s got %s", expected, r.String())
+	}
+}
diff --git a/pkg/thumbnails/resolution/resolutions.go b/pkg/thumbnails/resolution/resolutions.go
new file mode 100644
index 0000000000..a64bd9eedf
--- /dev/null
+++ b/pkg/thumbnails/resolution/resolutions.go
@@ -0,0 +1,58 @@
+package resolution
+
+import (
+	"fmt"
+	"math"
+)
+
+// Init creates an instance of Resolutions from resolution strings.
+func Init(rStrs []string) (Resolutions, error) {
+	var rs Resolutions
+	for _, rStr := range rStrs {
+		r, err := Parse(rStr)
+		if err != nil {
+			return nil, fmt.Errorf("failed to initialize resolutions: %s", err.Error())
+		}
+		rs = append(rs, r)
+	}
+	return rs, nil
+}
+
+// Resolutions represents the available thumbnail resolutions.
+type Resolutions []Resolution
+
+// ClosestMatch returns the resolution which is closest to the provided resolution.
+func (r Resolutions) ClosestMatch(width, height int) Resolution {
+	if len(r) == 0 {
+		return Resolution{Width: width, Height: height}
+	}
+
+	isLandscape := width > height
+	givenLen := math.Max(float64(width), float64(height))
+
+	// Initialize with the first resolution
+	match := r[0]
+	matchLen := dimensionLength(match, isLandscape)
+	minDiff := math.Abs(givenLen - float64(matchLen))
+
+	for i := 1; i < len(r); i++ {
+		r := r[i]
+		rLen := dimensionLength(r, isLandscape)
+		diff := math.Abs(givenLen - float64(rLen))
+
+		if diff <= minDiff {
+			minDiff = diff
+			match = r
+			continue
+		}
+	}
+
+	return match
+}
+
+func dimensionLength(r Resolution, landscape bool) int {
+	if landscape {
+		return r.Width
+	}
+	return r.Height
+}
diff --git a/pkg/thumbnails/resolution/resolutions_test.go b/pkg/thumbnails/resolution/resolutions_test.go
new file mode 100644
index 0000000000..37b0e83671
--- /dev/null
+++ b/pkg/thumbnails/resolution/resolutions_test.go
@@ -0,0 +1,91 @@
+package resolution
+
+import (
+	"testing"
+)
+
+func TestInitWithEmptyArray(t *testing.T) {
+	rs, err := Init([]string{})
+	if err != nil {
+		t.Errorf("Init with an empty array should not fail. Error: %s.\n", err.Error())
+	}
+	if len(rs) != 0 {
+		t.Error("Init with an empty array should return an empty Resolutions instance.\n")
+	}
+}
+
+func TestInitWithNil(t *testing.T) {
+	rs, err := Init(nil)
+	if err != nil {
+		t.Errorf("Init with nil parameter should not fail. Error: %s.\n", err.Error())
+	}
+	if len(rs) != 0 {
+		t.Error("Init with nil parameter should return an empty Resolutions instance.\n")
+	}
+}
+
+func TestInitWithInvalidValuesInArray(t *testing.T) {
+	_, err := Init([]string{"invalid"})
+	if err == nil {
+		t.Error("Init with invalid parameter should fail.\n")
+	}
+}
+
+func TestInit(t *testing.T) {
+	rs, err := Init([]string{"16x16"})
+	if err != nil {
+		t.Errorf("Init with valid parameter should not fail. Error: %s.\n", err.Error())
+	}
+	if len(rs) != 1 {
+		t.Errorf("resolutions has size %d, expected size %d.\n", len(rs), 1)
+	}
+}
+
+func TestInitWithMultipleResolutions(t *testing.T) {
+	rStrs := []string{"16x16", "32x32", "64x64", "128x128"}
+	rs, err := Init(rStrs)
+	if err != nil {
+		t.Errorf("Init with valid parameter should not fail. Error: %s.\n", err.Error())
+	}
+	if len(rs) != len(rStrs) {
+		t.Errorf("resolutions has size %d, expected size %d.\n", len(rs), len(rStrs))
+	}
+}
+
+func TestClosestMatchWithEmptyResolutions(t *testing.T) {
+	rs, _ := Init(nil)
+	width := 24
+	height := 24
+
+	r := rs.ClosestMatch(width, height)
+	if r.Width != width || r.Height != height {
+		t.Errorf("ClosestMatch from empty resolutions should return the given resolution")
+	}
+}
+
+func TestClosestMatch(t *testing.T) {
+	rs, _ := Init([]string{"16x16", "24x24", "32x32", "64x64", "128x128"})
+	table := [][]int{
+		[]int{17, 17, 16, 16},
+		[]int{12, 17, 16, 16},
+		[]int{24, 24, 24, 24},
+		[]int{20, 20, 24, 24},
+		[]int{20, 80, 64, 64},
+		[]int{80, 20, 64, 64},
+		[]int{48, 48, 64, 64},
+		[]int{1024, 1024, 128, 128},
+	}
+
+	for _, row := range table {
+		width := row[0]
+		height := row[1]
+		expectedWidth := row[2]
+		expectedHeight := row[3]
+
+		match := rs.ClosestMatch(width, height)
+
+		if match.Width != expectedWidth || match.Height != expectedHeight {
+			t.Errorf("Expected resolution %dx%d got %s", expectedWidth, expectedHeight, match.String())
+		}
+	}
+}

From 3de4584a45f7c3fe9a1ebd8519b22a23157b0c55 Mon Sep 17 00:00:00 2001
From: David Christofas <dchristofas@owncloud.com>
Date: Mon, 23 Mar 2020 11:52:33 +0100
Subject: [PATCH 2/8] use predefined resolutions for thumbnail generation

---
 pkg/command/server.go                         |  2 +-
 pkg/config/config.go                          | 20 ++++++----
 pkg/flagset/flagset.go                        | 10 ++++-
 pkg/server/grpc/server.go                     |  1 +
 pkg/service/v0/service.go                     | 35 ++++++++++-------
 pkg/thumbnails/resolution/resolution_test.go  | 14 +++++++
 pkg/thumbnails/resolution/resolutions.go      | 39 +++++++++++++------
 pkg/thumbnails/resolution/resolutions_test.go | 27 +++++++++++--
 pkg/thumbnails/storage/filesystem.go          |  3 +-
 pkg/thumbnails/storage/inmemory.go            |  2 +-
 pkg/thumbnails/storage/storage.go             |  9 +++--
 pkg/thumbnails/thumbnails.go                  | 19 +++++----
 12 files changed, 125 insertions(+), 56 deletions(-)

diff --git a/pkg/command/server.go b/pkg/command/server.go
index af6cafecf8..9967701efa 100644
--- a/pkg/command/server.go
+++ b/pkg/command/server.go
@@ -29,11 +29,11 @@ func Server(cfg *config.Config) *cli.Command {
 		Usage: "Start integrated server",
 		Flags: flagset.ServerWithConfig(cfg),
 		Before: func(c *cli.Context) error {
+			cfg.Thumbnail.Resolutions = c.StringSlice("thumbnail-resolution")
 			return nil
 		},
 		Action: func(c *cli.Context) error {
 			logger := NewLogger(cfg)
-
 			if cfg.Tracing.Enabled {
 				switch t := cfg.Tracing.Type; t {
 				case "agent":
diff --git a/pkg/config/config.go b/pkg/config/config.go
index e84b514b9e..37286518ab 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -33,13 +33,12 @@ type Tracing struct {
 
 // Config combines all available configuration parts.
 type Config struct {
-	File              string
-	Log               Log
-	Debug             Debug
-	Server            Server
-	Tracing           Tracing
-	FileSystemStorage FileSystemStorage
-	WebDavSource      WebDavSource
+	File      string
+	Log       Log
+	Debug     Debug
+	Server    Server
+	Tracing   Tracing
+	Thumbnail Thumbnail
 }
 
 // FileSystemStorage defines the available filesystem storage configuration.
@@ -52,6 +51,13 @@ type WebDavSource struct {
 	BaseURL string
 }
 
+// Thumbnail defines the available thumbnail related configuration.
+type Thumbnail struct {
+	Resolutions       []string
+	FileSystemStorage FileSystemStorage
+	WebDavSource      WebDavSource
+}
+
 // New initializes a new configuration with or without defaults.
 func New() *Config {
 	return &Config{}
diff --git a/pkg/flagset/flagset.go b/pkg/flagset/flagset.go
index 2f34817b1a..19b3f95065 100644
--- a/pkg/flagset/flagset.go
+++ b/pkg/flagset/flagset.go
@@ -142,14 +142,20 @@ func ServerWithConfig(cfg *config.Config) []cli.Flag {
 			Value:       filepath.Join(os.TempDir(), "ocis-thumbnails/"),
 			Usage:       "Root path of the filesystem storage directory",
 			EnvVars:     []string{"THUMBNAILS_FILESYSTEMSTORAGE_ROOT"},
-			Destination: &cfg.FileSystemStorage.RootDirectory,
+			Destination: &cfg.Thumbnail.FileSystemStorage.RootDirectory,
 		},
 		&cli.StringFlag{
 			Name:        "webdavsource-baseurl",
 			Value:       "http://localhost:9140/remote.php/webdav/",
 			Usage:       "Base url for a webdav api",
 			EnvVars:     []string{"THUMBNAILS_WEBDAVSOURCE_BASEURL"},
-			Destination: &cfg.WebDavSource.BaseURL,
+			Destination: &cfg.Thumbnail.WebDavSource.BaseURL,
+		},
+		&cli.StringSliceFlag{
+			Name:    "thumbnail-resolution",
+			Value:   cli.NewStringSlice("16x16", "32x32", "64x64", "128x128"),
+			Usage:   "--thumbnail-resolution 16x16 [--thumbnail-resolution 32x32]",
+			EnvVars: []string{"THUMBNAILS_RESOLUTIONs"},
 		},
 	}
 }
diff --git a/pkg/server/grpc/server.go b/pkg/server/grpc/server.go
index 96c64e1d0c..37a79b755a 100644
--- a/pkg/server/grpc/server.go
+++ b/pkg/server/grpc/server.go
@@ -24,6 +24,7 @@ func NewService(opts ...Option) grpc.Service {
 	{
 		thumbnail = svc.NewService(
 			svc.Config(options.Config),
+			svc.Logger(options.Logger),
 		)
 		thumbnail = svc.NewInstrument(thumbnail, options.Metrics)
 		thumbnail = svc.NewLogging(thumbnail, options.Logger)
diff --git a/pkg/service/v0/service.go b/pkg/service/v0/service.go
index 3a2f973ace..faf22ad1eb 100644
--- a/pkg/service/v0/service.go
+++ b/pkg/service/v0/service.go
@@ -8,23 +8,29 @@ import (
 	v0proto "github.com/owncloud/ocis-thumbnails/pkg/proto/v0"
 	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails"
 	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/imgsource"
+	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolution"
 	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/storage"
 )
 
 // NewService returns a service implementation for Service.
 func NewService(opts ...Option) v0proto.ThumbnailServiceHandler {
 	options := newOptions(opts...)
-
+	logger := options.Logger
+	resolutions, err := resolution.Init(options.Config.Thumbnail.Resolutions)
+	if err != nil {
+		logger.Fatal().Err(err).Msg("resolutions not configured correctly")
+	}
 	svc := Thumbnail{
 		manager: thumbnails.NewSimpleManager(
 			storage.NewFileSystemStorage(
-				options.Config.FileSystemStorage,
-				options.Logger,
+				options.Config.Thumbnail.FileSystemStorage,
+				logger,
 			),
-			options.Logger,
+			logger,
 		),
-		source: imgsource.NewWebDavSource(options.Config.WebDavSource),
-		logger: options.Logger,
+		resolutions: resolutions,
+		source:      imgsource.NewWebDavSource(options.Config.Thumbnail.WebDavSource),
+		logger:      logger,
 	}
 
 	return svc
@@ -32,9 +38,10 @@ func NewService(opts ...Option) v0proto.ThumbnailServiceHandler {
 
 // Thumbnail implements the GRPC handler.
 type Thumbnail struct {
-	manager thumbnails.Manager
-	source  imgsource.Source
-	logger  log.Logger
+	manager     thumbnails.Manager
+	resolutions resolution.Resolutions
+	source      imgsource.Source
+	logger      log.Logger
 }
 
 // GetThumbnail retrieves a thumbnail for an image
@@ -44,12 +51,12 @@ func (g Thumbnail) GetThumbnail(ctx context.Context, req *v0proto.GetRequest, rs
 		// TODO: better error responses
 		return fmt.Errorf("can't be encoded. filetype %s not supported", req.Filetype.String())
 	}
+	r := g.resolutions.ClosestMatch(int(req.Width), int(req.Height))
 	tCtx := thumbnails.Context{
-		Width:     int(req.Width),
-		Height:    int(req.Height),
-		ImagePath: req.Filepath,
-		Encoder:   encoder,
-		ETag:      req.Etag,
+		Resolution: r,
+		ImagePath:  req.Filepath,
+		Encoder:    encoder,
+		ETag:       req.Etag,
 	}
 
 	thumbnail := g.manager.GetStored(tCtx)
diff --git a/pkg/thumbnails/resolution/resolution_test.go b/pkg/thumbnails/resolution/resolution_test.go
index 18d6e46764..b8c3e6c883 100644
--- a/pkg/thumbnails/resolution/resolution_test.go
+++ b/pkg/thumbnails/resolution/resolution_test.go
@@ -9,6 +9,20 @@ func TestParseWithEmptyString(t *testing.T) {
 	}
 }
 
+func TestParseWithInvalidWidth(t *testing.T) {
+	_, err := Parse("invalidx42")
+	if err == nil {
+		t.Error("Parse with invalid width should return an error.")
+	}
+}
+
+func TestParseWithInvalidHeight(t *testing.T) {
+	_, err := Parse("42xinvalid")
+	if err == nil {
+		t.Error("Parse with invalid height should return an error.")
+	}
+}
+
 func TestParse(t *testing.T) {
 	rStr := "42x23"
 	r, _ := Parse(rStr)
diff --git a/pkg/thumbnails/resolution/resolutions.go b/pkg/thumbnails/resolution/resolutions.go
index a64bd9eedf..c17b47135c 100644
--- a/pkg/thumbnails/resolution/resolutions.go
+++ b/pkg/thumbnails/resolution/resolutions.go
@@ -3,6 +3,7 @@ package resolution
 import (
 	"fmt"
 	"math"
+	"sort"
 )
 
 // Init creates an instance of Resolutions from resolution strings.
@@ -15,6 +16,16 @@ func Init(rStrs []string) (Resolutions, error) {
 		}
 		rs = append(rs, r)
 	}
+	sort.Slice(rs, func(i, j int) bool {
+		left := rs[i]
+		right := rs[j]
+
+		leftSize := left.Width * left.Height
+		rightSize := right.Width * right.Height
+
+		return leftSize < rightSize
+	})
+
 	return rs, nil
 }
 
@@ -22,31 +33,37 @@ func Init(rStrs []string) (Resolutions, error) {
 type Resolutions []Resolution
 
 // ClosestMatch returns the resolution which is closest to the provided resolution.
+// If there is no exact match the resolution will be the next higher one.
+// If the given resolution is bigger than all available resolutions the biggest available one is used.
 func (r Resolutions) ClosestMatch(width, height int) Resolution {
 	if len(r) == 0 {
 		return Resolution{Width: width, Height: height}
 	}
 
 	isLandscape := width > height
-	givenLen := math.Max(float64(width), float64(height))
+	givenLen := int(math.Max(float64(width), float64(height)))
 
 	// Initialize with the first resolution
-	match := r[0]
-	matchLen := dimensionLength(match, isLandscape)
-	minDiff := math.Abs(givenLen - float64(matchLen))
+	var match Resolution
+	minDiff := math.MaxInt32
 
 	for i := 1; i < len(r); i++ {
-		r := r[i]
-		rLen := dimensionLength(r, isLandscape)
-		diff := math.Abs(givenLen - float64(rLen))
-
-		if diff <= minDiff {
-			minDiff = diff
-			match = r
+		current := r[i]
+		len := dimensionLength(current, isLandscape)
+		diff := givenLen - len
+		if diff > 0 {
 			continue
 		}
+		absDiff := int(math.Abs(float64(diff)))
+		if absDiff < minDiff {
+			minDiff = absDiff
+			match = current
+		}
 	}
 
+	if match == (Resolution{}) {
+		match = r[len(r)-1]
+	}
 	return match
 }
 
diff --git a/pkg/thumbnails/resolution/resolutions_test.go b/pkg/thumbnails/resolution/resolutions_test.go
index 37b0e83671..4ec67c43dc 100644
--- a/pkg/thumbnails/resolution/resolutions_test.go
+++ b/pkg/thumbnails/resolution/resolutions_test.go
@@ -52,6 +52,25 @@ func TestInitWithMultipleResolutions(t *testing.T) {
 	}
 }
 
+func TestInitWithMultipleResolutionsShouldBeSorted(t *testing.T) {
+	rStrs := []string{"32x32", "64x64", "16x16", "128x128"}
+	rs, err := Init(rStrs)
+	if err != nil {
+		t.Errorf("Init with valid parameter should not fail. Error: %s.\n", err.Error())
+	}
+
+	for i := 0; i < len(rs)-1; i++ {
+		current := rs[i]
+		currentSize := current.Width * current.Height
+		next := rs[i]
+		nextSize := next.Width * next.Height
+
+		if currentSize > nextSize {
+			t.Error("Resolutions are not sorted.")
+		}
+
+	}
+}
 func TestClosestMatchWithEmptyResolutions(t *testing.T) {
 	rs, _ := Init(nil)
 	width := 24
@@ -66,12 +85,12 @@ func TestClosestMatchWithEmptyResolutions(t *testing.T) {
 func TestClosestMatch(t *testing.T) {
 	rs, _ := Init([]string{"16x16", "24x24", "32x32", "64x64", "128x128"})
 	table := [][]int{
-		[]int{17, 17, 16, 16},
-		[]int{12, 17, 16, 16},
+		[]int{17, 17, 24, 24},
+		[]int{12, 17, 24, 24},
 		[]int{24, 24, 24, 24},
 		[]int{20, 20, 24, 24},
-		[]int{20, 80, 64, 64},
-		[]int{80, 20, 64, 64},
+		[]int{20, 80, 128, 128},
+		[]int{80, 20, 128, 128},
 		[]int{48, 48, 64, 64},
 		[]int{1024, 1024, 128, 128},
 	}
diff --git a/pkg/thumbnails/storage/filesystem.go b/pkg/thumbnails/storage/filesystem.go
index e59b77170e..c8f6042456 100644
--- a/pkg/thumbnails/storage/filesystem.go
+++ b/pkg/thumbnails/storage/filesystem.go
@@ -6,7 +6,6 @@ import (
 	"io/ioutil"
 	"os"
 	"path/filepath"
-	"strconv"
 
 	"github.com/owncloud/ocis-pkg/v2/log"
 	"github.com/owncloud/ocis-thumbnails/pkg/config"
@@ -68,7 +67,7 @@ func (s FileSystem) Set(key string, img []byte) error {
 func (s FileSystem) BuildKey(ctx Context) string {
 	etag := ctx.ETag
 	filetype := ctx.Types[0]
-	filename := strconv.Itoa(ctx.Width) + "x" + strconv.Itoa(ctx.Height) + "." + filetype
+	filename := ctx.Resolution.String() + "." + filetype
 
 	key := new(bytes.Buffer)
 	key.WriteString(etag[:2])
diff --git a/pkg/thumbnails/storage/inmemory.go b/pkg/thumbnails/storage/inmemory.go
index c8f02a9ae2..74a78befd5 100644
--- a/pkg/thumbnails/storage/inmemory.go
+++ b/pkg/thumbnails/storage/inmemory.go
@@ -32,7 +32,7 @@ func (s InMemory) Set(key string, thumbnail []byte) error {
 func (s InMemory) BuildKey(ctx Context) string {
 	parts := []string{
 		ctx.ETag,
-		string(ctx.Width) + "x" + string(ctx.Height),
+		ctx.Resolution.String(),
 		strings.Join(ctx.Types, ","),
 	}
 	return strings.Join(parts, "+")
diff --git a/pkg/thumbnails/storage/storage.go b/pkg/thumbnails/storage/storage.go
index 8f5f3d9de0..68de3c9ead 100644
--- a/pkg/thumbnails/storage/storage.go
+++ b/pkg/thumbnails/storage/storage.go
@@ -1,11 +1,12 @@
 package storage
 
+import "github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolution"
+
 // Context combines different attributes needed for storage operations.
 type Context struct {
-	ETag   string
-	Types  []string
-	Width  int
-	Height int
+	ETag       string
+	Types      []string
+	Resolution resolution.Resolution
 }
 
 // Storage defines the interface for a thumbnail store.
diff --git a/pkg/thumbnails/thumbnails.go b/pkg/thumbnails/thumbnails.go
index 76223228dc..289d03462c 100644
--- a/pkg/thumbnails/thumbnails.go
+++ b/pkg/thumbnails/thumbnails.go
@@ -6,16 +6,16 @@ import (
 
 	"github.com/nfnt/resize"
 	"github.com/owncloud/ocis-pkg/v2/log"
+	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolution"
 	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/storage"
 )
 
 // Context bundles information needed to generate a thumbnail for afile
 type Context struct {
-	Width     int
-	Height    int
-	ImagePath string
-	Encoder   Encoder
-	ETag      string
+	Resolution resolution.Resolution
+	ImagePath  string
+	Encoder    Encoder
+	ETag       string
 }
 
 // Manager is responsible for generating thumbnails
@@ -69,16 +69,15 @@ func (s SimpleManager) GetStored(ctx Context) []byte {
 }
 
 func (s SimpleManager) generate(ctx Context, img image.Image) image.Image {
-	thumbnail := resize.Thumbnail(uint(ctx.Width), uint(ctx.Height), img, resize.Lanczos2)
+	thumbnail := resize.Thumbnail(uint(ctx.Resolution.Width), uint(ctx.Resolution.Height), img, resize.Lanczos2)
 	return thumbnail
 }
 
 func mapToStorageContext(ctx Context) storage.Context {
 	sCtx := storage.Context{
-		ETag:   ctx.ETag,
-		Width:  ctx.Width,
-		Height: ctx.Height,
-		Types:  ctx.Encoder.Types(),
+		ETag:       ctx.ETag,
+		Resolution: ctx.Resolution,
+		Types:      ctx.Encoder.Types(),
 	}
 	return sCtx
 }

From 3daf985f4cfca6397346d5ab821ec5e2b1620b07 Mon Sep 17 00:00:00 2001
From: David Christofas <dchristofas@owncloud.com>
Date: Mon, 23 Mar 2020 12:00:04 +0100
Subject: [PATCH 3/8] add changelog

---
 changelog/unreleased/predefined-resolutions.md | 6 ++++++
 1 file changed, 6 insertions(+)
 create mode 100644 changelog/unreleased/predefined-resolutions.md

diff --git a/changelog/unreleased/predefined-resolutions.md b/changelog/unreleased/predefined-resolutions.md
new file mode 100644
index 0000000000..ce8d3e1989
--- /dev/null
+++ b/changelog/unreleased/predefined-resolutions.md
@@ -0,0 +1,6 @@
+Change: Use predefined resolutions for thumbnail generation 
+
+We implemented predefined resolutions to prevent attacker from flooding the service with a large number of thumbnails.
+The requested resolution gets mapped to the closest matching predefined resolution.
+
+https://github.com/owncloud/ocis-thumbnails/issues/7

From eb820e1ab79fd8af870b85bcd6a6550648bce9db Mon Sep 17 00:00:00 2001
From: David Christofas <C0rby@users.noreply.github.com>
Date: Tue, 24 Mar 2020 11:05:08 +0100
Subject: [PATCH 4/8] add comment to test structure

---
 pkg/thumbnails/resolution/resolutions_test.go | 1 +
 1 file changed, 1 insertion(+)

diff --git a/pkg/thumbnails/resolution/resolutions_test.go b/pkg/thumbnails/resolution/resolutions_test.go
index 4ec67c43dc..cb54e096cf 100644
--- a/pkg/thumbnails/resolution/resolutions_test.go
+++ b/pkg/thumbnails/resolution/resolutions_test.go
@@ -85,6 +85,7 @@ func TestClosestMatchWithEmptyResolutions(t *testing.T) {
 func TestClosestMatch(t *testing.T) {
 	rs, _ := Init([]string{"16x16", "24x24", "32x32", "64x64", "128x128"})
 	table := [][]int{
+		// width, height, expectedWidth, expectedHeight
 		[]int{17, 17, 24, 24},
 		[]int{12, 17, 24, 24},
 		[]int{24, 24, 24, 24},

From cfd6b9cf91d0ebd99bc834b8dd390a69ac4798a6 Mon Sep 17 00:00:00 2001
From: David Christofas <dchristofas@owncloud.com>
Date: Wed, 25 Mar 2020 11:56:39 +0100
Subject: [PATCH 5/8] fix type in flagset

---
 pkg/flagset/flagset.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pkg/flagset/flagset.go b/pkg/flagset/flagset.go
index 19b3f95065..60126809c3 100644
--- a/pkg/flagset/flagset.go
+++ b/pkg/flagset/flagset.go
@@ -155,7 +155,7 @@ func ServerWithConfig(cfg *config.Config) []cli.Flag {
 			Name:    "thumbnail-resolution",
 			Value:   cli.NewStringSlice("16x16", "32x32", "64x64", "128x128"),
 			Usage:   "--thumbnail-resolution 16x16 [--thumbnail-resolution 32x32]",
-			EnvVars: []string{"THUMBNAILS_RESOLUTIONs"},
+			EnvVars: []string{"THUMBNAILS_RESOLUTIONS"},
 		},
 	}
 }

From 39ea10a88637c86dcd92a4fc98018b4ef49bf6eb Mon Sep 17 00:00:00 2001
From: David Christofas <dchristofas@owncloud.com>
Date: Wed, 25 Mar 2020 14:37:13 +0100
Subject: [PATCH 6/8] small refactorings

---
 pkg/service/v0/service.go                      |  6 +++---
 .../{resolution => resolutions}/resolution.go  |  2 +-
 .../resolution_test.go                         |  2 +-
 .../{resolution => resolutions}/resolutions.go |  9 ++++-----
 .../resolutions_test.go                        | 18 +++++++++---------
 pkg/thumbnails/storage/storage.go              |  4 ++--
 pkg/thumbnails/thumbnails.go                   |  4 ++--
 7 files changed, 22 insertions(+), 23 deletions(-)
 rename pkg/thumbnails/{resolution => resolutions}/resolution.go (98%)
 rename pkg/thumbnails/{resolution => resolutions}/resolution_test.go (97%)
 rename pkg/thumbnails/{resolution => resolutions}/resolutions.go (89%)
 rename pkg/thumbnails/{resolution => resolutions}/resolutions_test.go (90%)

diff --git a/pkg/service/v0/service.go b/pkg/service/v0/service.go
index faf22ad1eb..c480d8ac1e 100644
--- a/pkg/service/v0/service.go
+++ b/pkg/service/v0/service.go
@@ -8,7 +8,7 @@ import (
 	v0proto "github.com/owncloud/ocis-thumbnails/pkg/proto/v0"
 	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails"
 	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/imgsource"
-	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolution"
+	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolutions"
 	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/storage"
 )
 
@@ -16,7 +16,7 @@ import (
 func NewService(opts ...Option) v0proto.ThumbnailServiceHandler {
 	options := newOptions(opts...)
 	logger := options.Logger
-	resolutions, err := resolution.Init(options.Config.Thumbnail.Resolutions)
+	resolutions, err := resolutions.New(options.Config.Thumbnail.Resolutions)
 	if err != nil {
 		logger.Fatal().Err(err).Msg("resolutions not configured correctly")
 	}
@@ -39,7 +39,7 @@ func NewService(opts ...Option) v0proto.ThumbnailServiceHandler {
 // Thumbnail implements the GRPC handler.
 type Thumbnail struct {
 	manager     thumbnails.Manager
-	resolutions resolution.Resolutions
+	resolutions resolutions.Resolutions
 	source      imgsource.Source
 	logger      log.Logger
 }
diff --git a/pkg/thumbnails/resolution/resolution.go b/pkg/thumbnails/resolutions/resolution.go
similarity index 98%
rename from pkg/thumbnails/resolution/resolution.go
rename to pkg/thumbnails/resolutions/resolution.go
index 514fe85744..14acab7e32 100644
--- a/pkg/thumbnails/resolution/resolution.go
+++ b/pkg/thumbnails/resolutions/resolution.go
@@ -1,4 +1,4 @@
-package resolution
+package resolutions
 
 import (
 	"fmt"
diff --git a/pkg/thumbnails/resolution/resolution_test.go b/pkg/thumbnails/resolutions/resolution_test.go
similarity index 97%
rename from pkg/thumbnails/resolution/resolution_test.go
rename to pkg/thumbnails/resolutions/resolution_test.go
index b8c3e6c883..ae407163f9 100644
--- a/pkg/thumbnails/resolution/resolution_test.go
+++ b/pkg/thumbnails/resolutions/resolution_test.go
@@ -1,4 +1,4 @@
-package resolution
+package resolutions
 
 import "testing"
 
diff --git a/pkg/thumbnails/resolution/resolutions.go b/pkg/thumbnails/resolutions/resolutions.go
similarity index 89%
rename from pkg/thumbnails/resolution/resolutions.go
rename to pkg/thumbnails/resolutions/resolutions.go
index c17b47135c..c6858aacf3 100644
--- a/pkg/thumbnails/resolution/resolutions.go
+++ b/pkg/thumbnails/resolutions/resolutions.go
@@ -1,4 +1,4 @@
-package resolution
+package resolutions
 
 import (
 	"fmt"
@@ -6,8 +6,8 @@ import (
 	"sort"
 )
 
-// Init creates an instance of Resolutions from resolution strings.
-func Init(rStrs []string) (Resolutions, error) {
+// New creates an instance of Resolutions from resolution strings.
+func New(rStrs []string) (Resolutions, error) {
 	var rs Resolutions
 	for _, rStr := range rStrs {
 		r, err := Parse(rStr)
@@ -47,8 +47,7 @@ func (r Resolutions) ClosestMatch(width, height int) Resolution {
 	var match Resolution
 	minDiff := math.MaxInt32
 
-	for i := 1; i < len(r); i++ {
-		current := r[i]
+	for _, current := range r {
 		len := dimensionLength(current, isLandscape)
 		diff := givenLen - len
 		if diff > 0 {
diff --git a/pkg/thumbnails/resolution/resolutions_test.go b/pkg/thumbnails/resolutions/resolutions_test.go
similarity index 90%
rename from pkg/thumbnails/resolution/resolutions_test.go
rename to pkg/thumbnails/resolutions/resolutions_test.go
index cb54e096cf..9a7583c566 100644
--- a/pkg/thumbnails/resolution/resolutions_test.go
+++ b/pkg/thumbnails/resolutions/resolutions_test.go
@@ -1,11 +1,11 @@
-package resolution
+package resolutions
 
 import (
 	"testing"
 )
 
 func TestInitWithEmptyArray(t *testing.T) {
-	rs, err := Init([]string{})
+	rs, err := New([]string{})
 	if err != nil {
 		t.Errorf("Init with an empty array should not fail. Error: %s.\n", err.Error())
 	}
@@ -15,7 +15,7 @@ func TestInitWithEmptyArray(t *testing.T) {
 }
 
 func TestInitWithNil(t *testing.T) {
-	rs, err := Init(nil)
+	rs, err := New(nil)
 	if err != nil {
 		t.Errorf("Init with nil parameter should not fail. Error: %s.\n", err.Error())
 	}
@@ -25,14 +25,14 @@ func TestInitWithNil(t *testing.T) {
 }
 
 func TestInitWithInvalidValuesInArray(t *testing.T) {
-	_, err := Init([]string{"invalid"})
+	_, err := New([]string{"invalid"})
 	if err == nil {
 		t.Error("Init with invalid parameter should fail.\n")
 	}
 }
 
 func TestInit(t *testing.T) {
-	rs, err := Init([]string{"16x16"})
+	rs, err := New([]string{"16x16"})
 	if err != nil {
 		t.Errorf("Init with valid parameter should not fail. Error: %s.\n", err.Error())
 	}
@@ -43,7 +43,7 @@ func TestInit(t *testing.T) {
 
 func TestInitWithMultipleResolutions(t *testing.T) {
 	rStrs := []string{"16x16", "32x32", "64x64", "128x128"}
-	rs, err := Init(rStrs)
+	rs, err := New(rStrs)
 	if err != nil {
 		t.Errorf("Init with valid parameter should not fail. Error: %s.\n", err.Error())
 	}
@@ -54,7 +54,7 @@ func TestInitWithMultipleResolutions(t *testing.T) {
 
 func TestInitWithMultipleResolutionsShouldBeSorted(t *testing.T) {
 	rStrs := []string{"32x32", "64x64", "16x16", "128x128"}
-	rs, err := Init(rStrs)
+	rs, err := New(rStrs)
 	if err != nil {
 		t.Errorf("Init with valid parameter should not fail. Error: %s.\n", err.Error())
 	}
@@ -72,7 +72,7 @@ func TestInitWithMultipleResolutionsShouldBeSorted(t *testing.T) {
 	}
 }
 func TestClosestMatchWithEmptyResolutions(t *testing.T) {
-	rs, _ := Init(nil)
+	rs, _ := New(nil)
 	width := 24
 	height := 24
 
@@ -83,7 +83,7 @@ func TestClosestMatchWithEmptyResolutions(t *testing.T) {
 }
 
 func TestClosestMatch(t *testing.T) {
-	rs, _ := Init([]string{"16x16", "24x24", "32x32", "64x64", "128x128"})
+	rs, _ := New([]string{"16x16", "24x24", "32x32", "64x64", "128x128"})
 	table := [][]int{
 		// width, height, expectedWidth, expectedHeight
 		[]int{17, 17, 24, 24},
diff --git a/pkg/thumbnails/storage/storage.go b/pkg/thumbnails/storage/storage.go
index 68de3c9ead..ca5ddf557c 100644
--- a/pkg/thumbnails/storage/storage.go
+++ b/pkg/thumbnails/storage/storage.go
@@ -1,12 +1,12 @@
 package storage
 
-import "github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolution"
+import "github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolutions"
 
 // Context combines different attributes needed for storage operations.
 type Context struct {
 	ETag       string
 	Types      []string
-	Resolution resolution.Resolution
+	Resolution resolutions.Resolution
 }
 
 // Storage defines the interface for a thumbnail store.
diff --git a/pkg/thumbnails/thumbnails.go b/pkg/thumbnails/thumbnails.go
index 289d03462c..fa22d398c7 100644
--- a/pkg/thumbnails/thumbnails.go
+++ b/pkg/thumbnails/thumbnails.go
@@ -6,13 +6,13 @@ import (
 
 	"github.com/nfnt/resize"
 	"github.com/owncloud/ocis-pkg/v2/log"
-	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolution"
+	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolutions"
 	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/storage"
 )
 
 // Context bundles information needed to generate a thumbnail for afile
 type Context struct {
-	Resolution resolution.Resolution
+	Resolution resolutions.Resolution
 	ImagePath  string
 	Encoder    Encoder
 	ETag       string

From 0e2223819d37d4280232ad4e672be44da2fe9ac8 Mon Sep 17 00:00:00 2001
From: David Christofas <dchristofas@owncloud.com>
Date: Wed, 25 Mar 2020 16:56:45 +0100
Subject: [PATCH 7/8] rename context

---
 pkg/service/v0/service.go            | 12 +++++-----
 pkg/thumbnails/storage/filesystem.go |  8 +++----
 pkg/thumbnails/storage/inmemory.go   |  8 +++----
 pkg/thumbnails/storage/storage.go    |  6 ++---
 pkg/thumbnails/thumbnails.go         | 36 ++++++++++++++--------------
 5 files changed, 35 insertions(+), 35 deletions(-)

diff --git a/pkg/service/v0/service.go b/pkg/service/v0/service.go
index c480d8ac1e..ca68414f43 100644
--- a/pkg/service/v0/service.go
+++ b/pkg/service/v0/service.go
@@ -52,36 +52,36 @@ func (g Thumbnail) GetThumbnail(ctx context.Context, req *v0proto.GetRequest, rs
 		return fmt.Errorf("can't be encoded. filetype %s not supported", req.Filetype.String())
 	}
 	r := g.resolutions.ClosestMatch(int(req.Width), int(req.Height))
-	tCtx := thumbnails.Context{
+	tr := thumbnails.Request{
 		Resolution: r,
 		ImagePath:  req.Filepath,
 		Encoder:    encoder,
 		ETag:       req.Etag,
 	}
 
-	thumbnail := g.manager.GetStored(tCtx)
+	thumbnail := g.manager.GetStored(tr)
 	if thumbnail != nil {
 		rsp.Thumbnail = thumbnail
-		rsp.Mimetype = tCtx.Encoder.MimeType()
+		rsp.Mimetype = tr.Encoder.MimeType()
 		return nil
 	}
 
 	auth := req.Authorization
 	sCtx := context.WithValue(ctx, imgsource.WebDavAuth, auth)
 	// TODO: clean up error handling
-	img, err := g.source.Get(sCtx, tCtx.ImagePath)
+	img, err := g.source.Get(sCtx, tr.ImagePath)
 	if err != nil {
 		return err
 	}
 	if img == nil {
 		return fmt.Errorf("could not retrieve image")
 	}
-	thumbnail, err = g.manager.Get(tCtx, img)
+	thumbnail, err = g.manager.Get(tr, img)
 	if err != nil {
 		return err
 	}
 
 	rsp.Thumbnail = thumbnail
-	rsp.Mimetype = tCtx.Encoder.MimeType()
+	rsp.Mimetype = tr.Encoder.MimeType()
 	return nil
 }
diff --git a/pkg/thumbnails/storage/filesystem.go b/pkg/thumbnails/storage/filesystem.go
index c8f6042456..dc45d9de03 100644
--- a/pkg/thumbnails/storage/filesystem.go
+++ b/pkg/thumbnails/storage/filesystem.go
@@ -64,10 +64,10 @@ func (s FileSystem) Set(key string, img []byte) error {
 // e.g. 97/9f/4c8db98f7b82e768ef478d3c8612/500x300.png
 //
 // The key also represents the path to the thumbnail in the filesystem under the configured root directory.
-func (s FileSystem) BuildKey(ctx Context) string {
-	etag := ctx.ETag
-	filetype := ctx.Types[0]
-	filename := ctx.Resolution.String() + "." + filetype
+func (s FileSystem) BuildKey(r Request) string {
+	etag := r.ETag
+	filetype := r.Types[0]
+	filename := r.Resolution.String() + "." + filetype
 
 	key := new(bytes.Buffer)
 	key.WriteString(etag[:2])
diff --git a/pkg/thumbnails/storage/inmemory.go b/pkg/thumbnails/storage/inmemory.go
index 74a78befd5..12017eed0c 100644
--- a/pkg/thumbnails/storage/inmemory.go
+++ b/pkg/thumbnails/storage/inmemory.go
@@ -29,11 +29,11 @@ func (s InMemory) Set(key string, thumbnail []byte) error {
 }
 
 // BuildKey generates a unique key to store and retrieve the thumbnail.
-func (s InMemory) BuildKey(ctx Context) string {
+func (s InMemory) BuildKey(r Request) string {
 	parts := []string{
-		ctx.ETag,
-		ctx.Resolution.String(),
-		strings.Join(ctx.Types, ","),
+		r.ETag,
+		r.Resolution.String(),
+		strings.Join(r.Types, ","),
 	}
 	return strings.Join(parts, "+")
 }
diff --git a/pkg/thumbnails/storage/storage.go b/pkg/thumbnails/storage/storage.go
index ca5ddf557c..48953a329b 100644
--- a/pkg/thumbnails/storage/storage.go
+++ b/pkg/thumbnails/storage/storage.go
@@ -2,8 +2,8 @@ package storage
 
 import "github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolutions"
 
-// Context combines different attributes needed for storage operations.
-type Context struct {
+// Request combines different attributes needed for storage operations.
+type Request struct {
 	ETag       string
 	Types      []string
 	Resolution resolutions.Resolution
@@ -13,5 +13,5 @@ type Context struct {
 type Storage interface {
 	Get(string) []byte
 	Set(string, []byte) error
-	BuildKey(Context) string
+	BuildKey(Request) string
 }
diff --git a/pkg/thumbnails/thumbnails.go b/pkg/thumbnails/thumbnails.go
index fa22d398c7..2a0600795d 100644
--- a/pkg/thumbnails/thumbnails.go
+++ b/pkg/thumbnails/thumbnails.go
@@ -10,8 +10,8 @@ import (
 	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/storage"
 )
 
-// Context bundles information needed to generate a thumbnail for afile
-type Context struct {
+// Request bundles information needed to generate a thumbnail for afile
+type Request struct {
 	Resolution resolutions.Resolution
 	ImagePath  string
 	Encoder    Encoder
@@ -21,10 +21,10 @@ type Context struct {
 // Manager is responsible for generating thumbnails
 type Manager interface {
 	// Get will return a thumbnail for a file
-	Get(Context, image.Image) ([]byte, error)
+	Get(Request, image.Image) ([]byte, error)
 	// GetStored loads the thumbnail from the storage.
 	// It will return nil if no image is stored for the given context.
-	GetStored(Context) []byte
+	GetStored(Request) []byte
 }
 
 // NewSimpleManager creates a new instance of SimpleManager
@@ -42,13 +42,13 @@ type SimpleManager struct {
 }
 
 // Get implements the Get Method of Manager
-func (s SimpleManager) Get(ctx Context, img image.Image) ([]byte, error) {
-	thumbnail := s.generate(ctx, img)
+func (s SimpleManager) Get(r Request, img image.Image) ([]byte, error) {
+	thumbnail := s.generate(r, img)
 
-	key := s.storage.BuildKey(mapToStorageContext(ctx))
+	key := s.storage.BuildKey(mapToStorageRequest(r))
 
 	buf := new(bytes.Buffer)
-	err := ctx.Encoder.Encode(buf, thumbnail)
+	err := r.Encoder.Encode(buf, thumbnail)
 	if err != nil {
 		return nil, err
 	}
@@ -62,22 +62,22 @@ func (s SimpleManager) Get(ctx Context, img image.Image) ([]byte, error) {
 
 // GetStored tries to get the stored thumbnail and return it.
 // If there is no cached thumbnail it will return nil
-func (s SimpleManager) GetStored(ctx Context) []byte {
-	key := s.storage.BuildKey(mapToStorageContext(ctx))
+func (s SimpleManager) GetStored(r Request) []byte {
+	key := s.storage.BuildKey(mapToStorageRequest(r))
 	stored := s.storage.Get(key)
 	return stored
 }
 
-func (s SimpleManager) generate(ctx Context, img image.Image) image.Image {
-	thumbnail := resize.Thumbnail(uint(ctx.Resolution.Width), uint(ctx.Resolution.Height), img, resize.Lanczos2)
+func (s SimpleManager) generate(r Request, img image.Image) image.Image {
+	thumbnail := resize.Thumbnail(uint(r.Resolution.Width), uint(r.Resolution.Height), img, resize.Lanczos2)
 	return thumbnail
 }
 
-func mapToStorageContext(ctx Context) storage.Context {
-	sCtx := storage.Context{
-		ETag:       ctx.ETag,
-		Resolution: ctx.Resolution,
-		Types:      ctx.Encoder.Types(),
+func mapToStorageRequest(r Request) storage.Request {
+	sR := storage.Request{
+		ETag:       r.ETag,
+		Resolution: r.Resolution,
+		Types:      r.Encoder.Types(),
 	}
-	return sCtx
+	return sR
 }

From e9c2de26a5d56716f46b22517070ad5610e41b04 Mon Sep 17 00:00:00 2001
From: David Christofas <dchristofas@owncloud.com>
Date: Thu, 26 Mar 2020 09:49:37 +0100
Subject: [PATCH 8/8] rename package

---
 pkg/service/v0/service.go                     | 20 +++++++++----------
 pkg/{thumbnails => thumbnail}/encoding.go     |  2 +-
 .../imgsource/imgsource.go                    |  0
 .../imgsource/webdav.go                       |  0
 .../resolution}/resolution.go                 |  2 +-
 .../resolution}/resolution_test.go            |  2 +-
 .../resolution}/resolutions.go                |  2 +-
 .../resolution}/resolutions_test.go           |  2 +-
 .../storage/filesystem.go                     |  0
 .../storage/inmemory.go                       |  0
 .../storage/storage.go                        |  4 ++--
 pkg/{thumbnails => thumbnail}/thumbnails.go   |  8 ++++----
 12 files changed, 21 insertions(+), 21 deletions(-)
 rename pkg/{thumbnails => thumbnail}/encoding.go (98%)
 rename pkg/{thumbnails => thumbnail}/imgsource/imgsource.go (100%)
 rename pkg/{thumbnails => thumbnail}/imgsource/webdav.go (100%)
 rename pkg/{thumbnails/resolutions => thumbnail/resolution}/resolution.go (98%)
 rename pkg/{thumbnails/resolutions => thumbnail/resolution}/resolution_test.go (97%)
 rename pkg/{thumbnails/resolutions => thumbnail/resolution}/resolutions.go (98%)
 rename pkg/{thumbnails/resolutions => thumbnail/resolution}/resolutions_test.go (99%)
 rename pkg/{thumbnails => thumbnail}/storage/filesystem.go (100%)
 rename pkg/{thumbnails => thumbnail}/storage/inmemory.go (100%)
 rename pkg/{thumbnails => thumbnail}/storage/storage.go (74%)
 rename pkg/{thumbnails => thumbnail}/thumbnails.go (91%)

diff --git a/pkg/service/v0/service.go b/pkg/service/v0/service.go
index ca68414f43..914968c8dd 100644
--- a/pkg/service/v0/service.go
+++ b/pkg/service/v0/service.go
@@ -6,22 +6,22 @@ import (
 
 	"github.com/owncloud/ocis-pkg/v2/log"
 	v0proto "github.com/owncloud/ocis-thumbnails/pkg/proto/v0"
-	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails"
-	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/imgsource"
-	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolutions"
-	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/storage"
+	"github.com/owncloud/ocis-thumbnails/pkg/thumbnail"
+	"github.com/owncloud/ocis-thumbnails/pkg/thumbnail/imgsource"
+	"github.com/owncloud/ocis-thumbnails/pkg/thumbnail/resolution"
+	"github.com/owncloud/ocis-thumbnails/pkg/thumbnail/storage"
 )
 
 // NewService returns a service implementation for Service.
 func NewService(opts ...Option) v0proto.ThumbnailServiceHandler {
 	options := newOptions(opts...)
 	logger := options.Logger
-	resolutions, err := resolutions.New(options.Config.Thumbnail.Resolutions)
+	resolutions, err := resolution.New(options.Config.Thumbnail.Resolutions)
 	if err != nil {
 		logger.Fatal().Err(err).Msg("resolutions not configured correctly")
 	}
 	svc := Thumbnail{
-		manager: thumbnails.NewSimpleManager(
+		manager: thumbnail.NewSimpleManager(
 			storage.NewFileSystemStorage(
 				options.Config.Thumbnail.FileSystemStorage,
 				logger,
@@ -38,21 +38,21 @@ func NewService(opts ...Option) v0proto.ThumbnailServiceHandler {
 
 // Thumbnail implements the GRPC handler.
 type Thumbnail struct {
-	manager     thumbnails.Manager
-	resolutions resolutions.Resolutions
+	manager     thumbnail.Manager
+	resolutions resolution.Resolutions
 	source      imgsource.Source
 	logger      log.Logger
 }
 
 // GetThumbnail retrieves a thumbnail for an image
 func (g Thumbnail) GetThumbnail(ctx context.Context, req *v0proto.GetRequest, rsp *v0proto.GetResponse) error {
-	encoder := thumbnails.EncoderForType(req.Filetype.String())
+	encoder := thumbnail.EncoderForType(req.Filetype.String())
 	if encoder == nil {
 		// TODO: better error responses
 		return fmt.Errorf("can't be encoded. filetype %s not supported", req.Filetype.String())
 	}
 	r := g.resolutions.ClosestMatch(int(req.Width), int(req.Height))
-	tr := thumbnails.Request{
+	tr := thumbnail.Request{
 		Resolution: r,
 		ImagePath:  req.Filepath,
 		Encoder:    encoder,
diff --git a/pkg/thumbnails/encoding.go b/pkg/thumbnail/encoding.go
similarity index 98%
rename from pkg/thumbnails/encoding.go
rename to pkg/thumbnail/encoding.go
index a4d4647bb9..d8d2d358bc 100644
--- a/pkg/thumbnails/encoding.go
+++ b/pkg/thumbnail/encoding.go
@@ -1,4 +1,4 @@
-package thumbnails
+package thumbnail
 
 import (
 	"image"
diff --git a/pkg/thumbnails/imgsource/imgsource.go b/pkg/thumbnail/imgsource/imgsource.go
similarity index 100%
rename from pkg/thumbnails/imgsource/imgsource.go
rename to pkg/thumbnail/imgsource/imgsource.go
diff --git a/pkg/thumbnails/imgsource/webdav.go b/pkg/thumbnail/imgsource/webdav.go
similarity index 100%
rename from pkg/thumbnails/imgsource/webdav.go
rename to pkg/thumbnail/imgsource/webdav.go
diff --git a/pkg/thumbnails/resolutions/resolution.go b/pkg/thumbnail/resolution/resolution.go
similarity index 98%
rename from pkg/thumbnails/resolutions/resolution.go
rename to pkg/thumbnail/resolution/resolution.go
index 14acab7e32..514fe85744 100644
--- a/pkg/thumbnails/resolutions/resolution.go
+++ b/pkg/thumbnail/resolution/resolution.go
@@ -1,4 +1,4 @@
-package resolutions
+package resolution
 
 import (
 	"fmt"
diff --git a/pkg/thumbnails/resolutions/resolution_test.go b/pkg/thumbnail/resolution/resolution_test.go
similarity index 97%
rename from pkg/thumbnails/resolutions/resolution_test.go
rename to pkg/thumbnail/resolution/resolution_test.go
index ae407163f9..b8c3e6c883 100644
--- a/pkg/thumbnails/resolutions/resolution_test.go
+++ b/pkg/thumbnail/resolution/resolution_test.go
@@ -1,4 +1,4 @@
-package resolutions
+package resolution
 
 import "testing"
 
diff --git a/pkg/thumbnails/resolutions/resolutions.go b/pkg/thumbnail/resolution/resolutions.go
similarity index 98%
rename from pkg/thumbnails/resolutions/resolutions.go
rename to pkg/thumbnail/resolution/resolutions.go
index c6858aacf3..2a83d45e7d 100644
--- a/pkg/thumbnails/resolutions/resolutions.go
+++ b/pkg/thumbnail/resolution/resolutions.go
@@ -1,4 +1,4 @@
-package resolutions
+package resolution
 
 import (
 	"fmt"
diff --git a/pkg/thumbnails/resolutions/resolutions_test.go b/pkg/thumbnail/resolution/resolutions_test.go
similarity index 99%
rename from pkg/thumbnails/resolutions/resolutions_test.go
rename to pkg/thumbnail/resolution/resolutions_test.go
index 9a7583c566..1190cc942a 100644
--- a/pkg/thumbnails/resolutions/resolutions_test.go
+++ b/pkg/thumbnail/resolution/resolutions_test.go
@@ -1,4 +1,4 @@
-package resolutions
+package resolution
 
 import (
 	"testing"
diff --git a/pkg/thumbnails/storage/filesystem.go b/pkg/thumbnail/storage/filesystem.go
similarity index 100%
rename from pkg/thumbnails/storage/filesystem.go
rename to pkg/thumbnail/storage/filesystem.go
diff --git a/pkg/thumbnails/storage/inmemory.go b/pkg/thumbnail/storage/inmemory.go
similarity index 100%
rename from pkg/thumbnails/storage/inmemory.go
rename to pkg/thumbnail/storage/inmemory.go
diff --git a/pkg/thumbnails/storage/storage.go b/pkg/thumbnail/storage/storage.go
similarity index 74%
rename from pkg/thumbnails/storage/storage.go
rename to pkg/thumbnail/storage/storage.go
index 48953a329b..a23a757d3c 100644
--- a/pkg/thumbnails/storage/storage.go
+++ b/pkg/thumbnail/storage/storage.go
@@ -1,12 +1,12 @@
 package storage
 
-import "github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolutions"
+import "github.com/owncloud/ocis-thumbnails/pkg/thumbnail/resolution"
 
 // Request combines different attributes needed for storage operations.
 type Request struct {
 	ETag       string
 	Types      []string
-	Resolution resolutions.Resolution
+	Resolution resolution.Resolution
 }
 
 // Storage defines the interface for a thumbnail store.
diff --git a/pkg/thumbnails/thumbnails.go b/pkg/thumbnail/thumbnails.go
similarity index 91%
rename from pkg/thumbnails/thumbnails.go
rename to pkg/thumbnail/thumbnails.go
index 2a0600795d..846cd60138 100644
--- a/pkg/thumbnails/thumbnails.go
+++ b/pkg/thumbnail/thumbnails.go
@@ -1,4 +1,4 @@
-package thumbnails
+package thumbnail
 
 import (
 	"bytes"
@@ -6,13 +6,13 @@ import (
 
 	"github.com/nfnt/resize"
 	"github.com/owncloud/ocis-pkg/v2/log"
-	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/resolutions"
-	"github.com/owncloud/ocis-thumbnails/pkg/thumbnails/storage"
+	"github.com/owncloud/ocis-thumbnails/pkg/thumbnail/resolution"
+	"github.com/owncloud/ocis-thumbnails/pkg/thumbnail/storage"
 )
 
 // Request bundles information needed to generate a thumbnail for afile
 type Request struct {
-	Resolution resolutions.Resolution
+	Resolution resolution.Resolution
 	ImagePath  string
 	Encoder    Encoder
 	ETag       string