feat(template): add Templating functionality and endpoint

cmd/svg-templater/main.go

@@ -5,9 +5,13 @@ import (
 
 	"tomatentum.net/svg-templater/internal/command"
 	"tomatentum.net/svg-templater/internal/database"
+	"tomatentum.net/svg-templater/pkg/format"
 )
 
 func main() {
+	if !format.CheckInkscape() {
+		panic("Inkscape not found")
+	}
 	if err := database.OpenSQLite(); err != nil {
 		log.Fatal("Failed opening DB:\n", err)
 		return

go.mod

@@ -2,10 +2,12 @@ module tomatentum.net/svg-templater
 
 go 1.24.9
 
+require github.com/glebarez/go-sqlite v1.22.0
+
 require (
 	github.com/dustin/go-humanize v1.0.1 // indirect
-	github.com/glebarez/go-sqlite v1.22.0 // indirect
 	github.com/google/uuid v1.5.0 // indirect
+	github.com/hymkor/exregexp-go v0.2.0 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
 	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
 	golang.org/x/sys v0.15.0 // indirect

go.sum

@@ -4,6 +4,8 @@ github.com/glebarez/go-sqlite v1.22.0 h1:uAcMJhaA6r3LHMTFgP0SifzgXg46yJkgxqyuyec
 github.com/glebarez/go-sqlite v1.22.0/go.mod h1:PlBIdHe0+aUEFn+r2/uthrWq4FxbzugL0L8Li6yQJbc=
 github.com/google/uuid v1.5.0 h1:1p67kYwdtXjb0gL0BPiP1Av9wiZPo5A8z2cWkTZ+eyU=
 github.com/google/uuid v1.5.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/hymkor/exregexp-go v0.2.0 h1:tyIB8S9gpUwiBi3aDXXXL2yIXqTMWZzW3hs+UNDqcRM=
+github.com/hymkor/exregexp-go v0.2.0/go.mod h1:bm661vkJcg9TbcYNr7QOcOgGlr+Jxy1Qb84YjVON3bg=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec h1:W09IVJc94icq4NjY3clb7Lk8O1qJ8BdBEF8z0ibU0rE=

internal/command/commandline.go

@@ -30,7 +30,7 @@ func HandleCommandline() {
 	} else if help {
 		flag.PrintDefaults()
 	} else {
-		svg.Storage = svg.NewFileStorage(datapath)
+		svg.Storage = svg.NewFileStorage(datapath, "public")
 		server.PrepareHTTP()
 		server.Start()
 	}

internal/database/svgdb.go

@@ -13,6 +13,8 @@ const SVGTABLECREATE string = `
 	);`
 
 const INSERTSVGSQL string = "INSERT INTO svg VALUES (?, ?);"
+const GETSPECIFICSVGSQL string = "SELECT * FROM svg WHERE name = ?;"
+const GETSVGSQL string = "SELECT * FROM svg;"
 
 func InsertSVG(data *svg.TemplateData) error {
 	json, err := json.Marshal(data.TemplateKeys)
@@ -26,3 +28,47 @@ func InsertSVG(data *svg.TemplateData) error {
 
 	return nil
 }
+
+func GetSVG() ([]svg.TemplateData, error) {
+	result, err := database.Query(GETSVGSQL)
+	if err != nil {
+		return nil, err
+	}
+	defer result.Close()
+	templates := make([]svg.TemplateData, 0)
+	for result.Next() {
+		var (
+			id       string
+			keysjson []byte
+			keys     []string
+		)
+		if err := result.Scan(&id, &keysjson); err != nil {
+			return nil, err
+		}
+		if err := json.Unmarshal(keysjson, &keys); err != nil {
+			return nil, err
+		}
+		templates = append(templates, svg.TemplateData{Id: id, TemplateKeys: keys})
+	}
+
+	if err := result.Err(); err != nil {
+		return nil, err
+	}
+	return templates, nil
+}
+
+func GetSpecificSVG(id string) (svg.TemplateData, error) {
+	result := database.QueryRow(GETSPECIFICSVGSQL, id)
+
+	var (
+		keysjson []byte
+		keys     []string
+	)
+	if err := result.Scan(&id, &keysjson); err != nil {
+		return svg.TemplateData{}, err
+	}
+	if err := json.Unmarshal(keysjson, &keys); err != nil {
+		return svg.TemplateData{}, err
+	}
+	return svg.TemplateData{Id: id, TemplateKeys: keys}, nil
+}

internal/routes/download.go

@@ -0,0 +1,105 @@
+package routes
+
+import (
+	"encoding/json"
+	"log"
+	"net/http"
+	"net/url"
+	"path/filepath"
+	"strconv"
+
+	"tomatentum.net/svg-templater/pkg/format"
+	"tomatentum.net/svg-templater/pkg/svg/actions"
+)
+
+type downloadRequest struct {
+	TemplateKeys map[string]string
+}
+
+type downloadResponse struct {
+	Url string
+}
+
+func DownloadSVG(w http.ResponseWriter, r *http.Request) {
+	contentType := r.Header.Get("Content-Type")
+	if contentType != "application/json" {
+		http.Error(w, "Incorrect Content-Type. Needs application/json.", http.StatusUnsupportedMediaType)
+		return
+	}
+	var request downloadRequest
+	if err := json.NewDecoder(r.Body).Decode(&request); err != nil {
+		http.Error(w, err.Error(), http.StatusBadRequest)
+		return
+	}
+
+	var err error
+	id := r.PathValue("id")
+	if id == "" {
+		http.Error(w, "No ID provided", http.StatusBadRequest)
+		return
+	}
+
+	widthString := r.URL.Query().Get("w")
+	width := 0
+	if widthString != "" {
+		width, err = strconv.Atoi(widthString)
+		if err != nil {
+			http.Error(w, "Invalid w parameter", http.StatusBadRequest)
+			return
+		}
+	}
+
+	heightString := r.URL.Query().Get("h")
+	height := 0
+	if heightString != "" {
+		height, err = strconv.Atoi(heightString)
+		if err != nil {
+			http.Error(w, "Invalid h parameter", http.StatusBadRequest)
+			return
+		}
+	}
+
+	convParam := format.ConversionParameters{
+		Format: r.URL.Query().Get("format"),
+		Width:  width,
+		Height: height,
+	}
+	if convParam.Format == "" {
+		convParam.Format = "svg"
+	}
+
+	templateParam := actions.TemplateParameters{
+		Id:   id,
+		Keys: request.TemplateKeys,
+	}
+
+	filename, err := actions.ProvideFile(&templateParam, &convParam)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	urlparsed := getPublicUrl(r, filename)
+	log.Printf("Made %s available as %s\n", id, urlparsed)
+	response := downloadResponse{
+		Url: urlparsed,
+	}
+	w.Header().Add("Content-Type", "application/json")
+	json, err := json.Marshal(response)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	w.Write(json)
+}
+
+func getPublicUrl(r *http.Request, path string) string {
+	newURL := url.URL{
+		Host: r.Host,
+		Path: filepath.Join("public", path),
+	}
+	newURL.Scheme = "http"
+	if r.TLS != nil {
+		newURL.Scheme = "https"
+	}
+	return newURL.String()
+}

internal/routes/upload.go

@@ -10,7 +10,7 @@ import (
 	"tomatentum.net/svg-templater/pkg/svg/actions"
 )
 
-func CreateSVG(writer http.ResponseWriter, r http.Request) {
+func CreateSVG(writer http.ResponseWriter, r *http.Request) {
 
 	contentType := r.Header.Get("Content-Type")
 	if contentType != "image/svg+xml" {

internal/server/http.go

@@ -7,19 +7,29 @@ import (
 
 	"tomatentum.net/svg-templater/internal/routes"
 	"tomatentum.net/svg-templater/pkg/auth"
+	"tomatentum.net/svg-templater/pkg/svg"
 )
 
 func PrepareHTTP() {
-	registerAuthorized("/", func(w http.ResponseWriter, r *http.Request) {
+	registerAuthorizedFunc("/", func(w http.ResponseWriter, r *http.Request) {
 		fmt.Fprintln(w, "You are authorized!")
 	})
-	registerAuthorized("/svg/", func(w http.ResponseWriter, r *http.Request) {
+	registerAuthorizedFunc("/svg/", func(w http.ResponseWriter, r *http.Request) {
 		if r.Method != "POST" {
 			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
 			return
 		}
-		routes.CreateSVG(w, *r)
+		routes.CreateSVG(w, r)
 	})
+	registerAuthorizedFunc("/svg/{id}", func(w http.ResponseWriter, r *http.Request) {
+		if r.Method != "GET" {
+			http.Error(w, "Method not allowed", http.StatusMethodNotAllowed)
+			return
+		}
+		routes.DownloadSVG(w, r)
+	})
+
+	http.Handle("/public/", http.StripPrefix("/public/", http.FileServer(svg.Storage.GetPublicDir())))
 }
 
 func Start() {
@@ -29,7 +39,11 @@ func Start() {
 	}
 }
 
-func registerAuthorized(path string, f func(w http.ResponseWriter, r *http.Request)) {
-	http.HandleFunc(path, auth.AuthMiddleware(http.HandlerFunc(f)))
+func registerAuthorized(path string, handler http.Handler) {
+	http.HandleFunc(path, auth.AuthMiddleware(handler))
 	log.Println("Registered authorized handler for", path)
 }
+
+func registerAuthorizedFunc(path string, f func(w http.ResponseWriter, r *http.Request)) {
+	registerAuthorized(path, http.HandlerFunc(f))
+}

pkg/format/formatconverter.go

@@ -0,0 +1,97 @@
+package format
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strconv"
+	"strings"
+
+	"tomatentum.net/svg-templater/pkg/svg"
+)
+
+type ConversionParameters struct {
+	Format        string
+	Width, Height int
+}
+
+func ConvertByte(svgblob []byte, param ConversionParameters) ([]byte, error) {
+	reader, err := ConvertReader(svgblob, param)
+	if err != nil {
+		return nil, err
+	}
+	defer reader.Close()
+
+	result, err := io.ReadAll(reader)
+	if err != nil {
+		return nil, err
+	}
+	return result, nil
+}
+
+func ConvertReader(svgblob []byte, param ConversionParameters) (io.ReadCloser, error) {
+	if param.Format == "svg" {
+		return io.NopCloser(bytes.NewReader(svgblob)), nil
+	}
+	file, err := svg.CreateTemp(bytes.NewReader(svgblob), "svg")
+	if err != nil {
+		return nil, err
+	}
+	defer os.Remove(file)
+
+	return runCommand(file, param)
+}
+
+func runCommand(input string, param ConversionParameters) (io.ReadCloser, error) {
+	var args []string
+
+	var outExt string
+	switch param.Format {
+	case "png":
+		args = append(args, "--export-type=png")
+		outExt = ".png"
+	case "jpg":
+		args = append(args, "--export-type=png") // inkscape doesn't export jpg directly
+		outExt = ".png"
+	case "pdf":
+		args = append(args, "--export-type=pdf")
+		outExt = ".pdf"
+	default:
+		return nil, fmt.Errorf("format not supported: %s", param.Format)
+	}
+
+	if param.Width > 0 {
+		args = append(args, "-w", strconv.Itoa(param.Width))
+	}
+	if param.Height > 0 {
+		args = append(args, "-h", strconv.Itoa(param.Height))
+	}
+
+	outFile := strings.TrimSuffix(input, filepath.Ext(input)) + outExt
+	args = append(args, "-o", outFile)
+	args = append(args, input)
+
+	cmd := exec.Command("/opt/homebrew/bin/inkscape", args...)
+	cmd.Dir = svg.TempDir
+
+	out, err := cmd.CombinedOutput()
+
+	if err != nil {
+		return nil, fmt.Errorf("inkscape failed: %w: %s", err, string(out))
+	}
+
+	file, err := os.Open(outFile)
+	if err != nil {
+		return nil, err
+	}
+
+	return file, nil
+}
+
+func CheckInkscape() bool {
+	_, err := exec.LookPath("inkscape")
+	return err == nil
+}

pkg/svg/actions/download.go

@@ -0,0 +1,22 @@
+package actions
+
+import (
+	"bytes"
+	"log"
+
+	"tomatentum.net/svg-templater/pkg/format"
+	"tomatentum.net/svg-templater/pkg/svg"
+)
+
+func ProvideFile(r *TemplateParameters, conversion *format.ConversionParameters) (string, error) {
+	templatedSvgblob, err := Template(r)
+	if err != nil {
+		return "", err
+	}
+	log.Printf("Converting %s to format %s (w=%d,h=%d)", r.Id, conversion.Format, conversion.Width, conversion.Height)
+	result, err := format.ConvertByte(templatedSvgblob, *conversion)
+	if err != nil {
+		return "", err
+	}
+	return svg.Storage.CreatePublic(bytes.NewReader(result), conversion.Format)
+}

pkg/svg/actions/template.go

@@ -0,0 +1,66 @@
+package actions
+
+import (
+	"errors"
+	"io"
+	"log"
+	"maps"
+	"regexp"
+	"slices"
+
+	"github.com/hymkor/exregexp-go"
+	"tomatentum.net/svg-templater/internal/database"
+	"tomatentum.net/svg-templater/pkg/svg"
+)
+
+type TemplateParameters struct {
+	Id   string
+	Keys map[string]string
+}
+
+func Template(r *TemplateParameters) ([]byte, error) {
+	mapkeys := slices.Collect(maps.Keys(r.Keys))
+	ok, err := verifyTemplate(r.Id, mapkeys)
+	if err != nil {
+		return nil, err
+	}
+	if !ok {
+		return nil, errors.New("Template does not exist.")
+	}
+	log.Printf("Replacing keys of %s template\n", r.Id)
+
+	reader, err := svg.Storage.Get(r.Id)
+	if err != nil {
+		return nil, err
+	}
+	defer reader.Close()
+	svgblob, err := io.ReadAll(reader)
+	if err != nil {
+		return nil, err
+	}
+	replaceAll(&svgblob, r.Keys)
+	log.Printf("Finished replacing keys of %s template\n", r.Id)
+	return svgblob, nil
+}
+
+func replaceAll(svgblob *[]byte, keys map[string]string) {
+	regex := regexp.MustCompile(svg.KeyRegex)
+	*svgblob = []byte(exregexp.ReplaceAllStringSubmatchFunc(regex, string(*svgblob), func(s []string) string {
+		log.Printf("Replacing key %s with %s\n", s[1], keys[s[1]])
+		return keys[s[1]]
+	}))
+}
+
+func verifyTemplate(id string, keys []string) (bool, error) {
+	data, err := database.GetSpecificSVG(id)
+	if err != nil {
+		return false, err
+	}
+
+	for _, key := range data.TemplateKeys {
+		if !slices.Contains(keys, key) {
+			return false, nil
+		}
+	}
+	return true, nil
+}

pkg/svg/actions/upload.go

@@ -27,9 +27,9 @@ func Create(svgbuf []byte) (svg.TemplateData, error) {
 	return data, nil
 }
 
-func populateKeys(data *svg.TemplateData, svg []byte) {
-	regex := regexp.MustCompile(`\{\{\s*(.*?)\s*\}\}`)
-	result := regex.FindAllSubmatch(svg, -1)
+func populateKeys(data *svg.TemplateData, svgblob []byte) {
+	regex := regexp.MustCompile(svg.KeyRegex)
+	result := regex.FindAllSubmatch(svgblob, -1)
 	templateKeys := make([]string, len(result))
 
 	for i, matches := range result {

pkg/svg/storage.go

@@ -3,26 +3,34 @@ package svg
 import (
 	"io"
 	"log"
+	"net/http"
 	"os"
 	"path/filepath"
+	"strings"
 )
 
 type SvgStorage interface {
 	Create(id string, svg io.Reader) (string, error)
-	Get(id string) (io.Reader, error)
+	Get(id string) (io.ReadCloser, error)
+	CreatePublic(data io.Reader, filetype string) (string, error)
+	GetPublic(path string) (io.ReadCloser, error)
+	GetPublicDir() http.Dir
 }
 
+var _ SvgStorage = FileSvgStorage{}
+var TempDir string = ""
+
 type FileSvgStorage struct {
-	basepath string
+	basepath, publicSubPath string
 }
 
-func NewFileStorage(path string) *FileSvgStorage {
+func NewFileStorage(path, publicSubPath string) *FileSvgStorage {
 	err := os.MkdirAll(path, 0755)
 	if err != nil {
 		panic(err)
 	}
 	log.Println("Initialized file storage handler")
-	return &FileSvgStorage{path}
+	return &FileSvgStorage{path, publicSubPath}
 }
 
 func (f FileSvgStorage) Create(id string, svg io.Reader) (string, error) {
@@ -42,10 +50,55 @@ func (f FileSvgStorage) Create(id string, svg io.Reader) (string, error) {
 	return file.Name(), nil
 }
 
-func (f FileSvgStorage) Get(id string) (io.Reader, error) {
-	file, err := os.Open(filepath.Join(f.basepath, "svg", id+".svg"))
+func (f FileSvgStorage) Get(id string) (io.ReadCloser, error) {
+	file, err := os.Open(filepath.Join(f.basepath, id+".svg"))
 	if err != nil {
 		return nil, err
 	}
 	return file, nil
 }
+
+func (f FileSvgStorage) CreatePublic(data io.Reader, filetype string) (string, error) {
+	path := filepath.Join(f.basepath, f.publicSubPath)
+	if err := os.MkdirAll(path, 0755); err != nil {
+		return "", err
+	}
+
+	file, err := os.CreateTemp(path, "*."+filetype)
+	if err != nil {
+		return "", err
+	}
+	defer file.Close()
+	_, err = io.Copy(file, data)
+	if err != nil {
+		return "", err
+	}
+
+	return strings.TrimPrefix(file.Name(), path), nil
+}
+
+func (f FileSvgStorage) GetPublic(path string) (io.ReadCloser, error) {
+	file, err := os.Open(filepath.Join(f.basepath, f.publicSubPath, path))
+	if err != nil {
+		return nil, err
+	}
+	return file, nil
+}
+
+func (f FileSvgStorage) GetPublicDir() http.Dir {
+	return http.Dir(filepath.Join(f.basepath, f.publicSubPath))
+}
+
+func CreateTemp(data io.Reader, filetype string) (string, error) {
+	file, err := os.CreateTemp(TempDir, "*."+filetype)
+	if err != nil {
+		return "", err
+	}
+	defer file.Close()
+	_, err = io.Copy(file, data)
+	if err != nil {
+		return "", err
+	}
+
+	return file.Name(), nil
+}

pkg/svg/templates.go

@@ -1,5 +1,7 @@
 package svg
 
+const KeyRegex string = `\{\{\s*(.*?)\s*\}\}`
+
 type TemplateData struct {
 	Id           string
 	TemplateKeys []string