Index the dimensions of images.

pkg/index/index.go

@@ -586,10 +586,10 @@ func (x *Index) EdgesTo(ref *blobref.BlobRef, opts *search.EdgesToOpts) (edges [
 	}
 	for _, parentRef := range permanodeParents {
 		edges = append(edges, &search.Edge{
-			From:      parentRef,
-			FromType:  "permanode",
-			To:        ref,
-                })
+			From:     parentRef,
+			FromType: "permanode",
+			To:       ref,
+		})
 	}
 	return edges, nil
 }

pkg/index/indextest/tests.go

@@ -18,6 +18,7 @@ package indextest
 
 import (
 	"fmt"
+	"io/ioutil"
 	"log"
 	"os"
 	"path/filepath"
@@ -253,6 +254,30 @@ func Index(t *testing.T, initIdx func() *index.Index) {
 	t.Logf("add-attribute claim %q points to member permanode %q", memberRef, pnChild)
 	memberRefTime := id.lastTime()
 
+	// TODO(bradfitz): add EXIF tests here, once that stuff is ready.
+	if false {
+		for i := 1; i <= 8; i++ {
+			fileBase := fmt.Sprintf("f%d-exif.jpg", i)
+			fileName := filepath.Join(findGoPathPackage("camlistore.org"), "pkg", "images", "testdata", fileBase)
+			contents, err := ioutil.ReadFile(fileName)
+			if err != nil {
+				t.Fatal(err)
+			}
+			id.UploadFile(fileBase, string(contents))
+		}
+	}
+
+	// Upload a basic image.
+	var jpegFileRef *blobref.BlobRef
+	{
+		fileName := filepath.Join(findGoPathPackage("camlistore.org"), "pkg", "index", "indextest", "testdata", "dude.jpg")
+		contents, err := ioutil.ReadFile(fileName)
+		if err != nil {
+			t.Fatal(err)
+		}
+		jpegFileRef, _ = id.UploadFile("dude.jpg", string(contents))
+	}
+
 	lastPermanodeMutation := id.lastTime()
 	id.dumpIndex(t)
 
@@ -261,6 +286,11 @@ func Index(t *testing.T, initIdx func() *index.Index) {
 		t.Fatalf("%q = %q, want %q", key, g, e)
 	}
 
+	key = "imagesize|" + jpegFileRef.String()
+	if g, e := id.Get(key), "50|100"; g != e {
+		t.Errorf("JPEG dude.jpg key %q = %q; want %q", key, g, e)
+	}
+
 	key = "have:" + pn.String()
 	pnSizeStr := id.Get(key)
 	if pnSizeStr == "" {
@@ -519,8 +549,8 @@ func EdgesTo(t *testing.T, initIdx func() *index.Index) {
 			t.Fatalf("num edges = %d; want 1", len(edges))
 		}
 		wantEdge := &search.Edge{
-			From: pn1,
-			To: pn2,
+			From:     pn1,
+			To:       pn2,
 			FromType: "permanode",
 		}
 		if got, want := edges[0].String(), wantEdge.String(); got != want {

pkg/index/keys.go

@@ -216,4 +216,16 @@ var (
 			{"name", typeStr},       // the name, if static.
 		},
 	}
+
+	// Width and height after any EXIF rotation.
+	keyImageSize = &keyType{
+		"imagesize",
+		[]part{
+			{"fileref", typeBlobRef}, // blobref of "file" schema blob
+		},
+		[]part{
+			{"width", typeStr},
+			{"height", typeStr},
+		},
+	}
 )

pkg/index/receive.go

@@ -21,7 +21,12 @@ import (
 	"crypto/sha1"
 	"errors"
 	"fmt"
+	"image"
+	_ "image/gif"
+	_ "image/jpeg"
+	_ "image/png"
 	"io"
+	"io/ioutil"
 	"log"
 	"strings"
 
@@ -121,7 +126,34 @@ func (ix *Index) populateFile(blobRef *blobref.BlobRef, ss *schema.Superset, bm
 		return nil
 	}
 	mime, reader := magic.MimeTypeFromReader(fr)
-	size, err := io.Copy(sha1, reader)
+
+	var copyDest io.Writer = sha1
+	var withCopyErr func(error) // or nil
+	if strings.HasPrefix(mime, "image/") {
+		pr, pw := io.Pipe()
+		copyDest = io.MultiWriter(copyDest, pw)
+		confc := make(chan *image.Config, 1)
+		go func() {
+			conf, _, err := image.DecodeConfig(pr)
+			defer io.Copy(ioutil.Discard, pr)
+			if err == nil {
+				confc <- &conf
+			} else {
+				confc <- nil
+			}
+		}()
+		withCopyErr = func(err error) {
+			pw.CloseWithError(err)
+			if conf := <-confc; conf != nil {
+				bm.Set(keyImageSize.Key(blobRef), keyImageSize.Val(fmt.Sprint(conf.Width), fmt.Sprint(conf.Height)))
+			}
+		}
+	}
+
+	size, err := io.Copy(copyDest, reader)
+	if f := withCopyErr; f != nil {
+		f(err)
+	}
 	if err != nil {
 		// TODO: job scheduling system to retry this spaced
 		// out max n times.  Right now our options are