[libgdata] core: Override GDataEntry::etag in GDataAccessRule

[Philip Withnall <pwithnall src gnome org>]

commit e5e811acdbe50c93de17575afd6683a88be180be
Author: Philip Withnall <philip tecnocode co uk>
Date:   Tue Oct 5 13:51:49 2010 +0100

    core: Override GDataEntry::etag in GDataAccessRule
    
    Access rules don't seem to support ETags (at least in Google Calendar), so
    we override GDataEntry::etag so that it's always NULL for access rules.

 gdata/gdata-access-rule.c |   14 +++++++++++++-
 gdata/gdata-entry.c       |   15 +++++++++++++--
 2 files changed, 26 insertions(+), 3 deletions(-)
---
diff --git a/gdata/gdata-access-rule.c b/gdata/gdata-access-rule.c
index 326ff86..cd40164 100644
--- a/gdata/gdata-access-rule.c
+++ b/gdata/gdata-access-rule.c
@@ -60,7 +60,8 @@ enum {
 	PROP_ROLE = 1,
 	PROP_SCOPE_TYPE,
 	PROP_SCOPE_VALUE,
-	PROP_EDITED
+	PROP_EDITED,
+	PROP_ETAG
 };
 
 G_DEFINE_TYPE (GDataAccessRule, gdata_access_rule, GDATA_TYPE_ENTRY)
@@ -141,6 +142,10 @@ gdata_access_rule_class_init (GDataAccessRuleClass *klass)
 	                                                     "Edited", "The last time the access rule was edited.",
 	                                                     -1, G_MAXINT64, -1,
 	                                                     G_PARAM_READABLE | G_PARAM_STATIC_STRINGS));
+
+	/* Override the ETag property since ETags don't seem to be supported for ACL entries. TODO: Investigate this further (might only be
+	 * unsupported for Google Calendar). */
+	g_object_class_override_property (gobject_class, PROP_ETAG, "etag");
 }
 
 static void notify_role_cb (GDataAccessRule *self, GParamSpec *pspec, gpointer user_data);
@@ -231,6 +236,10 @@ gdata_access_rule_get_property (GObject *object, guint property_id, GValue *valu
 		case PROP_EDITED:
 			g_value_set_int64 (value, priv->edited);
 			break;
+		case PROP_ETAG:
+			/* Never return an ETag */
+			g_value_set_string (value, NULL);
+			break;
 		default:
 			/* We don't have any other property... */
 			G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
@@ -257,6 +266,9 @@ gdata_access_rule_set_property (GObject *object, guint property_id, const GValue
 			self->priv->scope_value = g_value_dup_string (value);
 			g_object_notify (object, "scope-value");
 			break;
+		case PROP_ETAG:
+			/* Never set an ETag (note that this doesn't stop it being set in GDataEntry due to XML parsing) */
+			break;
 		default:
 			/* We don't have any other property... */
 			G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
diff --git a/gdata/gdata-entry.c b/gdata/gdata-entry.c
index 1a18ade..e4f9069 100644
--- a/gdata/gdata-entry.c
+++ b/gdata/gdata-entry.c
@@ -492,7 +492,7 @@ pre_get_xml (GDataParsable *parsable, GString *xml_string)
 	GDataEntryPrivate *priv = GDATA_ENTRY (parsable)->priv;
 
 	/* Add the entry's ETag, if available */
-	if (priv->etag != NULL)
+	if (gdata_entry_get_etag (GDATA_ENTRY (parsable)) != NULL)
 		g_string_append_printf (xml_string, " gd:etag='%s'", priv->etag);
 }
 
@@ -695,8 +695,19 @@ gdata_entry_get_id (GDataEntry *self)
 const gchar *
 gdata_entry_get_etag (GDataEntry *self)
 {
+	gchar *etag;
+
 	g_return_val_if_fail (GDATA_IS_ENTRY (self), NULL);
-	return self->priv->etag;
+
+	/* We have to check if the property's set since GDataAccessRule overrides it and sets it to always be NULL (since ACL entries don't support
+	 * ETags, for some reason). */
+	g_object_get (G_OBJECT (self), "etag", &etag, NULL);
+	if (etag != NULL) {
+		g_free (etag);
+		return self->priv->etag;
+	}
+
+	return NULL;
 }
 
 /**