[Tracker] [PATCH] Read XMP Sidecar

[Jason Kivlighn <jkivlighn gmail com>]

Here's a patch to have Tracker read XMP sidecar files.  It adds a
configure check for Exempi, enabling reading XMP if found.

One problem I see is how to handle updating the associated file when
it's sidecar file is updated.

Cheers,
Jason

Index: src/trackerd/tracker-metadata.c
===================================================================
--- src/trackerd/tracker-metadata.c     (revision 598)
+++ src/trackerd/tracker-metadata.c     (working copy)
@@ -83,7 +83,8 @@
                          "application/x-killustrator",
                          "application/x-kivio",
                          "application/x-kontour",
-                         "application/x-wpg"
+                         "application/x-wpg",
+                         "application/rdf+xml"
 };
 
 
Index: src/trackerd/tracker-db.c
===================================================================
--- src/trackerd/tracker-db.c   (revision 598)
+++ src/trackerd/tracker-db.c   (working copy)
@@ -26,9 +26,9 @@
 #include "tracker-email.h"
 #include "tracker-metadata.h"
 
-
 extern Tracker *tracker;
 
+#define XMP_MIME_TYPE "application/rdf+xml"
 
 typedef struct {
        DBConnection    *db_con;
@@ -844,8 +844,9 @@
 
        GHashTable      *meta_table;
        const char      *ext;
+       char            *filename, *dirname;
        char            *str_link_uri, *service_name;
-       gboolean        is_file_indexable, service_has_metadata, is_external_service, service_has_fulltext, 
service_has_thumbs;
+       gboolean        is_file_indexable, service_has_metadata, is_external_service, service_has_fulltext, 
service_has_thumbs, is_sidecar;
 
        const char *uri;
 
@@ -888,15 +889,20 @@
 
                tracker_add_metadata_to_table  (meta_table, g_strdup ("File:NameDelimited"), g_strdup (uri));
 
-               ext = strrchr (uri, '.');
+               dirname = g_path_get_dirname (uri);
+               filename = g_path_get_basename (uri);
+               ext = strrchr (filename, '.');
                if (ext) {
                        ext++;
                        tracker_debug ("file extension is %s", ext);
                        tracker_add_metadata_to_table  (meta_table, g_strdup ("File:Ext"), g_strdup (ext));
+                       is_sidecar = strcmp("xmp",ext) == 0;
+               } else {
+                       is_sidecar = FALSE;
                }
 
-               tracker_add_metadata_to_table  (meta_table, g_strdup ("File:Path"), g_path_get_dirname (uri));
-               tracker_add_metadata_to_table  (meta_table, g_strdup ("File:Name"), g_path_get_basename 
(uri));
+               tracker_add_metadata_to_table  (meta_table, g_strdup ("File:Path"), g_strdup(dirname));
+               tracker_add_metadata_to_table  (meta_table, g_strdup ("File:Name"), g_strdup(filename));
 
                if (str_link_uri) {
                        tracker_add_metadata_to_table  (meta_table, g_strdup ("File:Link"), str_link_uri);
@@ -911,18 +917,43 @@
                is_file_indexable = (!info->is_directory && (strcmp (info->mime, "unknown") != 0) && (strcmp 
(info->mime, "symlink") != 0) && tracker_file_is_indexable (info->uri));
 
                service_has_metadata = (is_external_service ||
-                                       (is_file_indexable && (tracker_str_in_array (service_name, 
services_with_metadata) != -1)));
+                                       (is_file_indexable && (tracker_str_in_array (service_name, 
services_with_metadata) != -1))) && !is_sidecar;
                service_has_fulltext = (is_external_service ||
-                                       (is_file_indexable && (tracker_str_in_array (service_name, 
services_with_text) != -1)));
+                                       (is_file_indexable && (tracker_str_in_array (service_name, 
services_with_text) != -1))) && !is_sidecar;
                service_has_thumbs = (is_external_service ||
                                      (is_file_indexable && (tracker_str_in_array (service_name, 
services_with_thumbs) != -1)));
 
+               #ifdef HAVE_EXEMPI
+               /* TODO: How can we update the file when the sidecar file changes? */
+               if ( !info->is_directory && !is_sidecar ) {
+                       gchar *basename;
+                       if ( ext ) {
+                               basename = g_strndup(filename,ext-filename-1);
+                       }
+                       else {
+                               basename = g_strdup(filename);
+                       }
 
+                       gchar *sidecar_uri = g_build_filename(dirname,g_strconcat(basename,".xmp",NULL),NULL);
+
+                       tracker_debug ("looking for xmp sidecar at %s", sidecar_uri);
+                       if ( g_file_test( sidecar_uri, G_FILE_TEST_EXISTS) ) {
+                               tracker_debug ("xmp sidecar found for %s", sidecar_uri);
+                               tracker_metadata_get_embedded (sidecar_uri, XMP_MIME_TYPE, meta_table);
+                       }
+
+                       g_free(sidecar_uri);
+                       g_free(basename);
+               }
+               #endif
+
                tracker_debug ("file %s has fulltext %d with service %s", info->uri, service_has_fulltext, 
service_name); 
                tracker_db_index_service (db_con, info, service_name, meta_table, uri, attachment_service, 
service_has_metadata, service_has_fulltext, service_has_thumbs);
 
                g_hash_table_destroy (meta_table);
 
+               g_free(filename);
+               g_free(dirname);
        } else {
                tracker_db_index_service (db_con, info, service_name, NULL, uri, NULL, FALSE, FALSE, FALSE);
 
Index: src/tracker-extract/tracker-extract.c
===================================================================
--- src/tracker-extract/tracker-extract.c       (revision 598)
+++ src/tracker-extract/tracker-extract.c       (working copy)
@@ -30,6 +30,11 @@
 
 #define MAX_MEM 128
 
+#ifdef HAVE_EXEMPI
+#include <exempi/xmp.h>
+#include <exempi/xmpconsts.h>
+#endif
+
 typedef enum {
        IGNORE_METADATA,
        NO_METADATA,
@@ -59,9 +64,12 @@
 #ifdef HAVE_LIBGSF
 void tracker_extract_msoffice  (gchar *, GHashTable *);
 #endif
+#ifdef HAVE_EXEMPI
+void tracker_extract_xmp       (gchar *, GHashTable *);
+#endif
 void tracker_extract_mp3       (gchar *, GHashTable *);
 #ifdef HAVE_VORBIS
-void tracker_extract_vorbis    (gchar *, GHashTable *);
+void tracker_extract_vorbis    (gchar *, GHashTable *);
 #endif
 void tracker_extract_png       (gchar *, GHashTable *);
 #ifdef HAVE_LIBEXIF
@@ -92,7 +100,10 @@
        { "application/msword",                         tracker_extract_msoffice        },
        { "application/vnd.ms-*",                       tracker_extract_msoffice        },
 #endif
-  
+#ifdef HAVE_EXEMPI
+       { "application/rdf+xml",                        tracker_extract_xmp             },
+#endif
+
        /* Video extractors */
 #ifdef HAVE_GSTREAMER
        { "video/*",                                    tracker_extract_gstreamer       },
@@ -183,7 +194,45 @@
 
 }
 
+void
+tracker_read_xmp (gchar *buffer, size_t len, GHashTable *metadata)
+{
+       #ifdef HAVE_EXEMPI
+       xmp_init();
 
+       XmpPtr xmp = xmp_new_empty();
+       xmp_parse(xmp, buffer, len);
+       if (xmp != NULL) {
+               XmpIteratorPtr iter = xmp_iterator_new(xmp, NULL, NULL, XMP_ITER_JUSTLEAFNODES);
+               XmpStringPtr the_schema = xmp_string_new();
+               XmpStringPtr the_path = xmp_string_new();
+               XmpStringPtr the_prop = xmp_string_new();
+       
+               while( xmp_iterator_next(iter, the_schema, the_path, the_prop, NULL) )
+               {
+                       const char *schema = xmp_string_cstr(the_schema);
+                       const char *name = xmp_string_cstr(the_path);
+                       const char *value = xmp_string_cstr(the_prop);
+                       if (value != NULL) {
+                               if ( strcmp(schema,NS_CC) == 0 ) {
+                                       if (g_str_has_suffix(name,"license")) {
+                                               g_hash_table_insert (metadata, g_strdup("File:License"), 
g_strdup (value));
+                                       }
+                               }
+                       }
+               }
+       
+               xmp_string_free(the_prop);
+               xmp_string_free(the_path);
+               xmp_string_free(the_schema);
+               xmp_iterator_free(iter);
+       
+               xmp_free(xmp);
+       }
+       xmp_terminate();
+       #endif
+}
+
 static GHashTable *
 tracker_get_file_metadata (const char *uri, char *mime)
 {
Index: src/tracker-extract/tracker-extract-xmp.c
===================================================================
--- src/tracker-extract/tracker-extract-xmp.c   (revision 0)
+++ src/tracker-extract/tracker-extract-xmp.c   (revision 0)
@@ -0,0 +1,40 @@
+/* Tracker Extract - extracts embedded metadata from files
+ * Copyright (C) 2007, Jason Kivlighn (jkivlighn gmail com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA  02110-1301, USA.
+ */
+
+#include "config.h"
+
+#ifdef HAVE_EXEMPI
+
+#include <glib.h>
+
+#include "tracker-extract.h"
+
+void tracker_extract_xmp (gchar* filename, GHashTable *metadata)
+{
+       gchar *contents;
+       gsize length;
+       GError *error;
+
+       if ( g_file_get_contents( filename, &contents, &length, &error ) )
+               tracker_read_xmp(contents, length, metadata);
+}
+
+#else
+#warning "Not building XMP metadata extractor."
+#endif  /* HAVE_EXEMPI */
Index: src/tracker-extract/tracker-extract.h
===================================================================
--- src/tracker-extract/tracker-extract.h       (revision 598)
+++ src/tracker-extract/tracker-extract.h       (working copy)
@@ -17,6 +17,13 @@
  * Boston, MA  02110-1301, USA.
  */
 
+#ifndef _TRACKER_EXTRACT_H_
+#define _TRACKER_EXTRACT_H_
+
 #include <glib.h>
 
 gboolean       tracker_spawn (char **argv, int timeout, char **tmp_stdout, int *exit_status);
+
+void           tracker_read_xmp (gchar *buffer, size_t len, GHashTable *metadata);
+
+#endif
Index: src/tracker-extract/Makefile.am
===================================================================
--- src/tracker-extract/Makefile.am     (revision 598)
+++ src/tracker-extract/Makefile.am     (working copy)
@@ -5,6 +5,7 @@
        $(LIBGSF_CFLAGS)                        \
        $(LIBGSF_CFLAGS)                        \
        $(GSTREAMER_CFLAGS)                     \
+       $(EXEMPI_CFLAGS)                        \
        $(XINE_CFLAGS)
 
 bin_PROGRAMS = tracker-extract
@@ -33,6 +34,7 @@
        tracker-extract-imagemagick.c           \
        tracker-extract-mplayer.c               \
        tracker-extract-totem.c                 \
+       tracker-extract-xmp.c                   \
        $(video_sources)
 
 tracker_extract_LDADD = $(GLIB2_LIBS)          \
@@ -41,4 +43,5 @@
        $(LIBEXIF_LIBS)                         \
        $(LIBGSF_LIBS)                          \
        $(GSTREAMER_LIBS)                       \
+       $(EXEMPI_LIBS)                          \
        $(XINE_LIBS)
Index: configure.ac
===================================================================
--- configure.ac        (revision 598)
+++ configure.ac        (working copy)
@@ -607,6 +607,25 @@
 
 #####################################################
 
+##################################################################
+# check for exempi
+##################################################################
+
+EXEMPI_REQUIRED=1.99.0
+
+AC_ARG_ENABLE(xmp, AC_HELP_STRING([--disable-xmp], [Disable XMP extraction]),,[enable_xmp=yes])
+if test "x$enable_xmp" = "xyes"; then
+       PKG_CHECK_MODULES(EXEMPI,[
+               exempi-2.0 >= $EXEMPI_REQUIRED],
+               [have_exempi=yes] , [have_exempi=no])
+       AC_SUBST(EXEMPI_CFLAGS)
+       AC_SUBST(EXEMPI_LIBS)
+else
+       have_exempi="no (disabled)"
+fi
+AM_CONDITIONAL(HAVE_EXEMPI, test "$have_exempi" = "yes")
+test "$have_exempi" = "yes" && AC_DEFINE(HAVE_EXEMPI, [], [Define if we have exempi])
+
 AC_CONFIG_FILES([
        Makefile
        tracker.pc
@@ -675,6 +694,7 @@
        exif (jpeg):                            $have_libexif
        gsf:                                    $have_libgsf
        video files:                            $videos_are_handled ($videos_handler)
+       embedded/sidecar xmp:                   $have_exempi
 
 "
 if test "x$enable_external_sqlite" = "xyes"; then