API: Disable gzip compression for /api/v1/dl endpoint #127 #1090

Required for compatibility with the Python HTTP client. In addition,
this commit refactors function names and adds tests.

Signed-off-by: Michael Mayer <michael@photoprism.app>

internal/api/download.go

@@ -0,0 +1,94 @@
+package api
+
+import (
+	"net/http"
+	"path/filepath"
+
+	"github.com/gin-gonic/gin"
+
+	"github.com/photoprism/photoprism/internal/api/download"
+	"github.com/photoprism/photoprism/internal/config/customize"
+	"github.com/photoprism/photoprism/internal/entity/query"
+	"github.com/photoprism/photoprism/internal/photoprism"
+	"github.com/photoprism/photoprism/internal/photoprism/get"
+	"github.com/photoprism/photoprism/pkg/clean"
+	"github.com/photoprism/photoprism/pkg/fs"
+	"github.com/photoprism/photoprism/pkg/rnd"
+)
+
+// TODO: GET /api/v1/dl/file/:hash
+// TODO: GET /api/v1/dl/photo/:uid
+// TODO: GET /api/v1/dl/album/:uid
+
+// DownloadName returns the download file name type.
+func DownloadName(c *gin.Context) customize.DownloadName {
+	switch c.Query("name") {
+	case "file":
+		return customize.DownloadNameFile
+	case "share":
+		return customize.DownloadNameShare
+	case "original":
+		return customize.DownloadNameOriginal
+	default:
+		return get.Config().Settings().Download.Name
+	}
+}
+
+// GetDownload returns the raw file data.
+//
+//	@Summary	returns the raw file data
+//	@Id			GetDownload
+//	@Tags		Images, Files
+//	@Produce	application/octet-stream
+//	@Failure	403,404	{file}	image/svg+xml
+//	@Success	200		{file}	application/octet-stream
+//	@Param		file	path	string	true	"file hash or unique download id"
+//	@Router		/api/v1/dl/{file} [get]
+func GetDownload(router *gin.RouterGroup) {
+	router.GET("/dl/:file", func(c *gin.Context) {
+		id := clean.Token(c.Param("file"))
+
+		// Check for temporary download if the file is identified by a UUID string.
+		if rnd.IsUUID(id) {
+			fileName, fileErr := download.Find(id)
+
+			if fileErr != nil {
+				AbortForbidden(c)
+				return
+			} else if !fs.FileExists(fileName) {
+				AbortNotFound(c)
+				return
+			}
+
+			c.FileAttachment(fileName, filepath.Base(fileName))
+			return
+		}
+
+		// If the file is identified by its hash, a valid download token is required.
+		if InvalidDownloadToken(c) {
+			c.Data(http.StatusForbidden, "image/svg+xml", brokenIconSvg)
+			return
+		}
+
+		f, err := query.FileByHash(id)
+
+		if err != nil {
+			c.AbortWithStatusJSON(404, gin.H{"error": err.Error()})
+			return
+		}
+
+		fileName := photoprism.FileName(f.FileRoot, f.FileName)
+
+		if !fs.FileExists(fileName) {
+			log.Errorf("download: file %s is missing", clean.Log(f.FileName))
+			c.Data(404, "image/svg+xml", brokenIconSvg)
+
+			// Set missing flag so that the file doesn't show up in search results anymore.
+			logErr("download", f.Update("FileMissing", true))
+
+			return
+		}
+
+		c.FileAttachment(fileName, f.DownloadName(DownloadName(c), 0))
+	})
+}