[tracker-miners/sam/info-show-eligible: 2/2] cli: If there's no info file, show whether it's eligible for indexing

[Sam Thursfield <sthursfield src gnome org>]

commit c30d92f539fc1593911a1f13004a712175c92056
Author: Sam Thursfield <sam afuera me uk>
Date:   Fri Oct 9 18:07:23 2020 +0200

    cli: If there's no info file, show whether it's eligible for indexing
    
    If there's no data you usually want to know why, so let's give a clue
    right away.
    
    Before:
    
        $ > tracker3 info  ~/Documents/pdf-doc.pdf
        Querying information for entity: '/home/sam/Documents/pdf-doc.pdf'
        Results:
    
        $ tracker3 info  ~/Documents/pdf-doc.pdf --turtle
        @prefix nco: <http://tracker.api.gnome.org/ontology/v3/nco#> .
        ... many more prefixes and nothing else
    
    After:
    
        $ > tracker3 info  ~/Documents/pdf-doc.pdf
        Querying information for entity: '/home/sam/Documents/pdf-doc.pdf'
          No metadata available for that URI
        Data object “/home/sam/Documents/pdf-doc.pdf” currently exists
          File is NOT eligible to be indexed (not an indexed folder)
    
        $ > tracker3 info  ~/Documents/pdf-doc.pdf --turtle
        @prefix nco: <http://tracker.api.gnome.org/ontology/v3/nco#> .
        ... many more prefixes
    
        # No metadata available for <file:///home/sam/Documents/pdf-doc.pdf>
    
    Closes https://gitlab.gnome.org/GNOME/tracker-miners/-/issues/126

 src/tracker/tracker-info.c | 80 +++++++++++++++++++++++++++++++---------------
 1 file changed, 54 insertions(+), 26 deletions(-)
---
diff --git a/src/tracker/tracker-info.c b/src/tracker/tracker-info.c
index 1de70434f..7ed395595 100644
--- a/src/tracker/tracker-info.c
+++ b/src/tracker/tracker-info.c
@@ -198,7 +198,7 @@ print_key_and_value (GHashTable  *prefixes,
        }
 }
 
-static void
+static gboolean
 print_plain (gchar               *urn_or_filename,
              gchar               *urn,
              TrackerSparqlCursor *cursor,
@@ -207,6 +207,7 @@ print_plain (gchar               *urn_or_filename,
 {
        gchar *fts_key = NULL;
        gchar *fts_value = NULL;
+       gboolean has_output = FALSE;
 
        while (tracker_sparql_cursor_next (cursor, NULL, NULL)) {
                const gchar *key = tracker_sparql_cursor_get_string (cursor, 0, NULL);
@@ -216,6 +217,11 @@ print_plain (gchar               *urn_or_filename,
                        continue;
                }
 
+               if (!has_output) {
+                       g_print ("%s:\n", _("Results"));
+                       has_output = TRUE;
+               }
+
                /* Don't display nie:plainTextContent */
                if (strcmp (key, "http://tracker.api.gnome.org/ontology/v3/nie#plainTextContent";) == 0) {
                        if (plain_text_content) {
@@ -236,6 +242,8 @@ print_plain (gchar               *urn_or_filename,
 
        g_free (fts_key);
        g_free (fts_value);
+
+       return has_output;
 }
 
 /* print a URI prefix in Turtle format */
@@ -285,7 +293,7 @@ format_urn (GHashTable  *prefixes,
 }
 
 /* Print triples for a urn in Turtle format */
-static void
+static gboolean
 print_turtle (gchar               *urn,
               TrackerSparqlCursor *cursor,
               GHashTable          *prefixes,
@@ -294,6 +302,7 @@ print_turtle (gchar               *urn,
        gchar *subject;
        gchar *predicate;
        gchar *object;
+       gboolean has_output = FALSE;
 
        if (G_UNLIKELY (full_namespaces)) {
                subject = g_strdup (urn);
@@ -316,6 +325,8 @@ print_turtle (gchar               *urn,
                        continue;
                }
 
+               has_output = TRUE;
+
                predicate = format_urn (prefixes, key, full_namespaces);
 
                if (g_ascii_strcasecmp (is_resource, "true") == 0) {
@@ -337,6 +348,8 @@ print_turtle (gchar               *urn,
        }
 
        g_free (subject);
+
+       return has_output;
 }
 
 static TrackerSparqlConnection *
@@ -346,6 +359,21 @@ create_connection (GError **error)
                                                  NULL, NULL, error);
 }
 
+static gboolean
+output_eligible_status_for_file (gchar   *path,
+                                 GError **error)
+{
+       g_autofree char *tracker_miner_fs_path;
+
+       tracker_miner_fs_path = g_build_filename (LIBEXECDIR, "tracker-miner-fs-3", NULL);
+
+       {
+               char *argv[] = {tracker_miner_fs_path, "--eligible", path, NULL };
+
+               return g_spawn_sync (NULL, argv, NULL, G_SPAWN_DEFAULT, NULL, NULL, NULL, NULL, NULL, error);
+       }
+}
+
 static int
 info_run (void)
 {
@@ -353,6 +381,7 @@ info_run (void)
        GError *error = NULL;
        GHashTable *prefixes;
        gchar **p;
+       gboolean has_output = FALSE;
 
        connection = create_connection (&error);
 
@@ -377,7 +406,6 @@ info_run (void)
 
        for (p = filenames; *p; p++) {
                TrackerSparqlCursor *cursor = NULL;
-               GError *error = NULL;
                gchar *uri = NULL;
                gchar *query;
                gchar *urn = NULL;
@@ -446,7 +474,6 @@ info_run (void)
 
                cursor = tracker_sparql_connection_query (connection, query, NULL, &error);
 
-               g_free (uri);
                g_free (query);
 
                if (error) {
@@ -458,25 +485,36 @@ info_run (void)
                        continue;
                }
 
-               if (!cursor) {
-                       g_print ("  %s\n",
-                                _("No metadata available for that URI"));
-               } else {
+               if (cursor) {
                        if (turtle) {
-                               print_turtle (urn, cursor, prefixes, full_namespaces);
+                               has_output = print_turtle (urn, cursor, prefixes, full_namespaces);
                        } else {
-                               g_print ("%s:\n", _("Results"));
-
-                               print_plain (*p, urn, cursor, prefixes, full_namespaces);
+                               has_output = print_plain (*p, urn, cursor, prefixes, full_namespaces);
                        }
 
+                       g_object_unref (cursor);
+               }
+
+               if (has_output) {
                        g_print ("\n");
+               } else if (turtle) {
+                       g_print ("# No metadata available for <%s>\n", uri);
+               } else {
+                       g_print ("  %s\n",
+                                _("No metadata available for that URI"));
+                       output_eligible_status_for_file (*p, &error);
 
-                       g_object_unref (cursor);
+                       if (error) {
+                               g_printerr ("%s: %s\n",
+                                           _("Could not get eligible status: "),
+                                           error->message);
+                               g_clear_error (&error);
+                       }
                }
 
                g_print ("\n");
 
+               g_free (uri);
                g_free (urn);
        }
 
@@ -490,29 +528,19 @@ static int
 info_run_eligible (void)
 {
        char **p;
-       char *tracker_miner_fs_path;
-       GError *error = NULL;
-
-       tracker_miner_fs_path = g_build_filename (LIBEXECDIR, "tracker-miner-fs-3", NULL);
+       g_autoptr (GError) error = NULL;
 
        for (p = filenames; *p; p++) {
-               char *argv[] = {tracker_miner_fs_path,
-                               "--eligible", *p, NULL };
-
-               g_spawn_sync(NULL, argv, NULL, G_SPAWN_DEFAULT, NULL, NULL, NULL, NULL, NULL, &error);
+               output_eligible_status_for_file (*p, &error);
 
                if (error) {
                        g_printerr ("%s: %s\n",
-                                   _("Could not run tracker-extract: "),
+                                   _("Could not get eligible status: "),
                                    error->message);
-                       g_error_free (error);
-                       g_free (tracker_miner_fs_path);
                        return EXIT_FAILURE;
                }
        }
 
-       g_free (tracker_miner_fs_path);
-
        return EXIT_SUCCESS;
 }