builder: Add support for defining extensions in flatpak-builder

This takes a list of properties and generate finish arguments.
Additionally you can specify "bundle": true, which causes f-b to emit
an actual extension implementation, similar to e.g. the locale
and debuginfo extension.

builder/Makefile.am.inc

@@ -8,6 +8,8 @@ flatpak_builder_SOURCES = \
 	builder/builder-manifest.h \
 	builder/builder-options.c \
 	builder/builder-options.h \
+	builder/builder-extension.c \
+	builder/builder-extension.h \
 	builder/builder-module.c \
 	builder/builder-module.h \
 	builder/builder-post-process.c \

builder/builder-extension.c

@@ -0,0 +1,425 @@
+/* builder-extension.c
+ *
+ * Copyright (C) 2015 Red Hat, Inc
+ *
+ * This file is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This file 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *       Alexander Larsson <alexl@redhat.com>
+ */
+
+#include "config.h"
+
+#include <string.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/statfs.h>
+
+#include <glib/gi18n.h>
+#include <gio/gio.h>
+#include "libglnx/libglnx.h"
+
+#include "flatpak-utils.h"
+#include "flatpak-run.h"
+#include "builder-utils.h"
+#include "builder-extension.h"
+
+struct BuilderExtension
+{
+  GObject         parent;
+
+  char           *name;
+  char           *directory;
+  gboolean        bundle;
+  gboolean        autodelete;
+  gboolean        no_autodownload;
+  gboolean        subdirectories;
+  char           *add_ld_path;
+  char           *download_if;
+  char           *enable_if;
+  char           *merge_dirs;
+  char           *subdirectory_suffix;
+  char           *version;
+  char           *versions;
+};
+
+typedef struct
+{
+  GObjectClass parent_class;
+} BuilderExtensionClass;
+
+G_DEFINE_TYPE (BuilderExtension, builder_extension, G_TYPE_OBJECT);
+
+enum {
+  PROP_0,
+  PROP_DIRECTORY,
+  PROP_BUNDLE,
+  PROP_AUTODELETE,
+  PROP_ADD_LD_PATH,
+  PROP_DOWNLOAD_IF,
+  PROP_ENABLE_IF,
+  PROP_MERGE_DIRS,
+  PROP_NO_AUTODOWNLOAD,
+  PROP_SUBDIRECTORIES,
+  PROP_SUBDIRECTORY_SUFFIX,
+  PROP_VERSION,
+  PROP_VERSIONS,
+  LAST_PROP
+};
+
+static void
+builder_extension_finalize (GObject *object)
+{
+  BuilderExtension *self = (BuilderExtension *) object;
+
+  g_free (self->name);
+  g_free (self->directory);
+  g_free (self->add_ld_path);
+  g_free (self->download_if);
+  g_free (self->enable_if);
+  g_free (self->merge_dirs);
+  g_free (self->subdirectory_suffix);
+  g_free (self->version);
+  g_free (self->versions);
+
+  G_OBJECT_CLASS (builder_extension_parent_class)->finalize (object);
+}
+
+static void
+builder_extension_get_property (GObject    *object,
+                                guint       prop_id,
+                                GValue     *value,
+                                GParamSpec *pspec)
+{
+  BuilderExtension *self = BUILDER_EXTENSION (object);
+
+  switch (prop_id)
+    {
+    case PROP_DIRECTORY:
+      g_value_set_string (value, self->directory);
+      break;
+
+    case PROP_BUNDLE:
+      g_value_set_boolean (value, self->bundle);
+      break;
+
+    case PROP_AUTODELETE:
+      g_value_set_boolean (value, self->autodelete);
+      break;
+
+    case PROP_NO_AUTODOWNLOAD:
+      g_value_set_boolean (value, self->autodelete);
+      break;
+
+    case PROP_SUBDIRECTORIES:
+      g_value_set_boolean (value, self->autodelete);
+      break;
+
+    case PROP_ADD_LD_PATH:
+      g_value_set_string (value, self->add_ld_path);
+      break;
+
+    case PROP_DOWNLOAD_IF:
+      g_value_set_string (value, self->download_if);
+      break;
+
+    case PROP_ENABLE_IF:
+      g_value_set_string (value, self->enable_if);
+      break;
+
+    case PROP_MERGE_DIRS:
+      g_value_set_string (value, self->merge_dirs);
+      break;
+
+    case PROP_SUBDIRECTORY_SUFFIX:
+      g_value_set_string (value, self->subdirectory_suffix);
+      break;
+
+    case PROP_VERSION:
+      g_value_set_string (value, self->version);
+      break;
+
+    case PROP_VERSIONS:
+      g_value_set_string (value, self->versions);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+builder_extension_set_property (GObject      *object,
+                                guint         prop_id,
+                                const GValue *value,
+                                GParamSpec   *pspec)
+{
+  BuilderExtension *self = BUILDER_EXTENSION (object);
+
+  switch (prop_id)
+    {
+    case PROP_DIRECTORY:
+      g_clear_pointer (&self->directory, g_free);
+      self->directory = g_value_dup_string (value);
+      break;
+
+    case PROP_BUNDLE:
+      self->bundle = g_value_get_boolean (value);
+      break;
+
+    case PROP_AUTODELETE:
+      self->autodelete = g_value_get_boolean (value);
+      break;
+
+    case PROP_NO_AUTODOWNLOAD:
+      self->no_autodownload = g_value_get_boolean (value);
+      break;
+
+    case PROP_SUBDIRECTORIES:
+      self->subdirectories = g_value_get_boolean (value);
+      break;
+
+    case PROP_ADD_LD_PATH:
+      g_clear_pointer (&self->add_ld_path, g_free);
+      self->add_ld_path = g_value_dup_string (value);
+      break;
+
+    case PROP_DOWNLOAD_IF:
+      g_clear_pointer (&self->download_if, g_free);
+      self->download_if = g_value_dup_string (value);
+      break;
+
+    case PROP_ENABLE_IF:
+      g_clear_pointer (&self->enable_if, g_free);
+      self->enable_if = g_value_dup_string (value);
+      break;
+
+    case PROP_MERGE_DIRS:
+      g_clear_pointer (&self->merge_dirs, g_free);
+      self->merge_dirs = g_value_dup_string (value);
+      break;
+
+    case PROP_SUBDIRECTORY_SUFFIX:
+      g_clear_pointer (&self->subdirectory_suffix, g_free);
+      self->subdirectory_suffix = g_value_dup_string (value);
+      break;
+
+    case PROP_VERSION:
+      g_clear_pointer (&self->version, g_free);
+      self->version = g_value_dup_string (value);
+      break;
+
+    case PROP_VERSIONS:
+      g_clear_pointer (&self->versions, g_free);
+      self->versions = g_value_dup_string (value);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+builder_extension_class_init (BuilderExtensionClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->finalize = builder_extension_finalize;
+  object_class->get_property = builder_extension_get_property;
+  object_class->set_property = builder_extension_set_property;
+
+  g_object_class_install_property (object_class,
+                                   PROP_DIRECTORY,
+                                   g_param_spec_string ("directory",
+                                                        "",
+                                                        "",
+                                                        NULL,
+                                                        G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_BUNDLE,
+                                   g_param_spec_boolean ("bundle",
+                                                         "",
+                                                         "",
+                                                         FALSE,
+                                                         G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_AUTODELETE,
+                                   g_param_spec_boolean ("autodelete",
+                                                         "",
+                                                         "",
+                                                         FALSE,
+                                                         G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_NO_AUTODOWNLOAD,
+                                   g_param_spec_boolean ("no-autodownload",
+                                                         "",
+                                                         "",
+                                                         FALSE,
+                                                         G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_SUBDIRECTORIES,
+                                   g_param_spec_boolean ("subdirectories",
+                                                         "",
+                                                         "",
+                                                         FALSE,
+                                                         G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_ADD_LD_PATH,
+                                   g_param_spec_string ("add-ld-path",
+                                                        "",
+                                                        "",
+                                                        NULL,
+                                                        G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_DOWNLOAD_IF,
+                                   g_param_spec_string ("download-if",
+                                                        "",
+                                                        "",
+                                                        NULL,
+                                                        G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_ENABLE_IF,
+                                   g_param_spec_string ("enable-if",
+                                                        "",
+                                                        "",
+                                                        NULL,
+                                                        G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_MERGE_DIRS,
+                                   g_param_spec_string ("merge-dirs",
+                                                        "",
+                                                        "",
+                                                        NULL,
+                                                        G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_SUBDIRECTORY_SUFFIX,
+                                   g_param_spec_string ("subdirectory-suffix",
+                                                        "",
+                                                        "",
+                                                        NULL,
+                                                        G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_VERSION,
+                                   g_param_spec_string ("version",
+                                                        "",
+                                                        "",
+                                                        NULL,
+                                                        G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_VERSIONS,
+                                   g_param_spec_string ("versions",
+                                                        "",
+                                                        "",
+                                                        NULL,
+                                                        G_PARAM_READWRITE));
+}
+
+static void
+builder_extension_init (BuilderExtension *self)
+{
+}
+
+void
+builder_extension_set_name (BuilderExtension *self,
+                            const char *name)
+{
+  g_free (self->name);
+  self->name = g_strdup (name);
+}
+
+const char *
+builder_extension_get_name (BuilderExtension *self)
+{
+  return self->name;
+}
+
+
+gboolean
+builder_extension_is_bundled (BuilderExtension *self)
+{
+  return self->bundle;
+}
+
+const char *
+builder_extension_get_directory (BuilderExtension *self)
+{
+  return self->directory;
+}
+
+static void
+add_arg (BuilderExtension  *self,
+         GPtrArray *args,
+         const char *key,
+         const char *value)
+{
+  if (value == NULL)
+    return;
+  g_ptr_array_add (args,
+                   g_strdup_printf ("--extension=%s=%s=%s", self->name, key, value));
+}
+
+static void
+add_argb (BuilderExtension  *self,
+          GPtrArray *args,
+          const char *key,
+          gboolean val)
+{
+  if (val)
+    add_arg (self, args, key, "true");
+}
+
+void
+builder_extension_add_finish_args (BuilderExtension  *self,
+                                   GPtrArray *args)
+{
+  if (self->directory == NULL)
+    {
+      g_warning ("No directory specified for extension '%s'", self->name);
+      return;
+    }
+
+  add_arg (self, args, FLATPAK_METADATA_KEY_DIRECTORY, self->directory);
+  add_argb (self, args, FLATPAK_METADATA_KEY_AUTODELETE, self->autodelete);
+  add_argb (self, args, FLATPAK_METADATA_KEY_NO_AUTODOWNLOAD, self->no_autodownload);
+  add_argb (self, args, FLATPAK_METADATA_KEY_SUBDIRECTORIES, self->subdirectories);
+  add_arg (self, args, FLATPAK_METADATA_KEY_ADD_LD_PATH, self->add_ld_path);
+  add_arg (self, args, FLATPAK_METADATA_KEY_DOWNLOAD_IF, self->download_if);
+  add_arg (self, args, FLATPAK_METADATA_KEY_ENABLE_IF, self->enable_if);
+  add_arg (self, args, FLATPAK_METADATA_KEY_MERGE_DIRS, self->merge_dirs);
+  add_arg (self, args, FLATPAK_METADATA_KEY_SUBDIRECTORY_SUFFIX, self->subdirectory_suffix);
+  add_arg (self, args, FLATPAK_METADATA_KEY_VERSION, self->version);
+  add_arg (self, args, FLATPAK_METADATA_KEY_VERSIONS, self->versions);
+}
+
+void
+builder_extension_checksum (BuilderExtension  *self,
+                            BuilderCache   *cache,
+                            BuilderContext *context)
+{
+  builder_cache_checksum_str (cache, BUILDER_EXTENSION_CHECKSUM_VERSION);
+  builder_cache_checksum_str (cache, self->name);
+  builder_cache_checksum_str (cache, self->directory);
+  builder_cache_checksum_boolean (cache, self->bundle);
+  builder_cache_checksum_boolean (cache, self->autodelete);
+  builder_cache_checksum_boolean (cache, self->no_autodownload);
+  builder_cache_checksum_boolean (cache, self->subdirectories);
+  builder_cache_checksum_str (cache, self->add_ld_path);
+  builder_cache_checksum_str (cache, self->download_if);
+  builder_cache_checksum_str (cache, self->enable_if);
+  builder_cache_checksum_str (cache, self->merge_dirs);
+  builder_cache_checksum_str (cache, self->subdirectory_suffix);
+  builder_cache_checksum_str (cache, self->version);
+  builder_cache_checksum_str (cache, self->versions);
+}

builder/builder-extension.h

@@ -0,0 +1,59 @@
+/*
+ * Copyright © 2017 Red Hat, Inc
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *       Alexander Larsson <alexl@redhat.com>
+ */
+
+#ifndef __BUILDER_EXTENSION_H__
+#define __BUILDER_EXTENSION_H__
+
+#include <json-glib/json-glib.h>
+
+#include "builder-context.h"
+#include "builder-cache.h"
+
+G_BEGIN_DECLS
+
+typedef struct BuilderExtension BuilderExtension;
+
+#define BUILDER_TYPE_EXTENSION (builder_extension_get_type ())
+#define BUILDER_EXTENSION(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), BUILDER_TYPE_EXTENSION, BuilderExtension))
+#define BUILDER_IS_EXTENSION(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), BUILDER_TYPE_EXTENSION))
+
+/* Bump this if format changes in incompatible ways to force rebuild */
+#define BUILDER_EXTENSION_CHECKSUM_VERSION "1"
+
+GType builder_extension_get_type (void);
+
+void   builder_extension_set_name (BuilderExtension *self,
+                                   const char *name);
+const char * builder_extension_get_name (BuilderExtension *self);
+
+gboolean builder_extension_is_bundled (BuilderExtension *self);
+const char * builder_extension_get_directory (BuilderExtension *self);
+
+void    builder_extension_add_finish_args (BuilderExtension  *self,
+                                           GPtrArray *args);
+void     builder_extension_checksum (BuilderExtension  *self,
+                                     BuilderCache   *cache,
+                                     BuilderContext *context);
+
+G_DEFINE_AUTOPTR_CLEANUP_FUNC (BuilderExtension, g_object_unref)
+
+G_END_DECLS
+
+#endif /* __BUILDER_EXTENSION_H__ */

builder/builder-main.c

@@ -170,6 +170,7 @@ do_export (BuilderContext *build_context,
            gboolean        runtime,
            const gchar    *location,
            const gchar    *directory,
+           char          **exclude_dirs,
            const gchar    *branch,
            const gchar    *collection_id,
            ...)
@@ -212,6 +213,12 @@ do_export (BuilderContext *build_context,
       g_ptr_array_add (args, g_strdup ((gchar *) arg));
   va_end (ap);
 
+  if (exclude_dirs)
+    {
+      for (i = 0; exclude_dirs[i] != NULL; i++)
+        g_ptr_array_add (args, g_strdup_printf ("--exclude=/%s/*", exclude_dirs[i]));
+    }
+
   /* Mandatory positional arguments. */
   g_ptr_array_add (args, g_strdup (location));
   g_ptr_array_add (args, g_strdup (directory));
@@ -740,12 +747,14 @@ main (int    argc,
     {
       g_autoptr(GFile) debuginfo_metadata = NULL;
       g_autoptr(GFile) sourcesinfo_metadata = NULL;
+      g_auto(GStrv) exclude_dirs = builder_manifest_get_exclude_dirs (manifest);
+      GList *l;
 
       g_print ("Exporting %s to repo\n", builder_manifest_get_id (manifest));
 
       if (!do_export (build_context, &error,
                       FALSE,
-                      opt_repo, app_dir_path, builder_manifest_get_branch (manifest),
+                      opt_repo, app_dir_path, exclude_dirs, builder_manifest_get_branch (manifest),
                       builder_manifest_get_collection_id (manifest),
                       "--exclude=/lib/debug/*",
                       "--include=/lib/debug/app",
@@ -778,7 +787,7 @@ main (int    argc,
           files_arg = g_strconcat (builder_context_get_build_runtime (build_context) ? "--files=usr" : "--files=files",
                                    "/share/runtime/locale/", NULL);
           if (!do_export (build_context, &error, TRUE,
-                          opt_repo, app_dir_path, builder_manifest_get_branch (manifest),
+                          opt_repo, app_dir_path, NULL, builder_manifest_get_branch (manifest),
                           builder_manifest_get_collection_id (manifest),
                           metadata_arg,
                           files_arg,
@@ -797,7 +806,7 @@ main (int    argc,
           g_print ("Exporting %s to repo\n", debug_id);
 
           if (!do_export (build_context, &error, TRUE,
-                          opt_repo, app_dir_path, builder_manifest_get_branch (manifest),
+                          opt_repo, app_dir_path, NULL, builder_manifest_get_branch (manifest),
                           builder_manifest_get_collection_id (manifest),
                           "--metadata=metadata.debuginfo",
                           builder_context_get_build_runtime (build_context) ? "--files=usr/lib/debug" : "--files=files/lib/debug",
@@ -808,6 +817,35 @@ main (int    argc,
             }
         }
 
+      for (l = builder_manifest_get_add_extensions (manifest); l != NULL; l = l->next)
+        {
+          BuilderExtension *e = l->data;
+          const char *extension_id = NULL;
+          g_autofree char *metadata_arg = NULL;
+          g_autofree char *files_arg = NULL;
+
+          if (!builder_extension_is_bundled (e))
+            continue;
+
+          extension_id = builder_extension_get_name (e);
+          g_print ("Exporting %s to repo\n", extension_id);
+
+          metadata_arg = g_strdup_printf ("--metadata=metadata.%s", extension_id);
+          files_arg = g_strdup_printf ("--files=%s/%s",
+                                       builder_context_get_build_runtime (build_context) ? "usr" : "files",
+                                       builder_extension_get_directory (e));
+
+          if (!do_export (build_context, &error, TRUE,
+                          opt_repo, app_dir_path, NULL, builder_manifest_get_branch (manifest),
+                          builder_manifest_get_collection_id (manifest),
+                          metadata_arg, files_arg,
+                          NULL))
+            {
+              g_printerr ("Export failed: %s\n", error->message);
+              return 1;
+            }
+        }
+
       /* Export sources extensions */
       sourcesinfo_metadata = g_file_get_child (app_dir, "metadata.sources");
       if (g_file_query_exists (sourcesinfo_metadata, NULL))
@@ -816,7 +854,7 @@ main (int    argc,
           g_print ("Exporting %s to repo\n", sources_id);
 
           if (!do_export (build_context, &error, TRUE,
-                          opt_repo, app_dir_path, builder_manifest_get_branch (manifest),
+                          opt_repo, app_dir_path, NULL, builder_manifest_get_branch (manifest),
                           builder_manifest_get_collection_id (manifest),
                           "--metadata=metadata.sources",
                           "--files=sources",
@@ -835,7 +873,7 @@ main (int    argc,
           g_print ("Exporting %s to repo\n", platform_id);
 
           if (!do_export (build_context, &error, TRUE,
-                          opt_repo, app_dir_path, builder_manifest_get_branch (manifest),
+                          opt_repo, app_dir_path, NULL, builder_manifest_get_branch (manifest),
                           builder_manifest_get_collection_id (manifest),
                           "--metadata=metadata.platform",
                           "--files=platform",
@@ -868,7 +906,7 @@ main (int    argc,
           metadata_arg = g_strdup_printf ("--metadata=%s", name);
           files_arg = g_strconcat ("--files=platform/share/runtime/locale/", NULL);
           if (!do_export (build_context, &error, TRUE,
-                          opt_repo, app_dir_path, builder_manifest_get_branch (manifest),
+                          opt_repo, app_dir_path, NULL, builder_manifest_get_branch (manifest),
                           builder_manifest_get_collection_id (manifest),
                           metadata_arg,
                           files_arg,

builder/builder-manifest.c

@@ -31,6 +31,7 @@
 #include "builder-utils.h"
 #include "flatpak-utils.h"
 #include "builder-post-process.h"
+#include "builder-extension.h"
 
 #include "libglnx/libglnx.h"
 
@@ -95,6 +96,7 @@ struct BuilderManifest
   BuilderOptions *build_options;
   GList          *modules;
   GList          *expanded_modules;
+  GList          *add_extensions;
 };
 
 typedef struct
@@ -149,6 +151,7 @@ enum {
   PROP_DESKTOP_FILE_NAME_PREFIX,
   PROP_DESKTOP_FILE_NAME_SUFFIX,
   PROP_COLLECTION_ID,
+  PROP_ADD_EXTENSIONS,
   LAST_PROP
 };
 
@@ -174,6 +177,7 @@ builder_manifest_finalize (GObject *object)
   g_free (self->command);
   g_clear_object (&self->build_options);
   g_list_free_full (self->modules, g_object_unref);
+  g_list_free_full (self->add_extensions, g_object_unref);
   g_list_free (self->expanded_modules);
   g_strfreev (self->cleanup);
   g_strfreev (self->cleanup_commands);
@@ -322,6 +326,10 @@ builder_manifest_get_property (GObject    *object,
       g_value_set_pointer (value, self->modules);
       break;
 
+    case PROP_ADD_EXTENSIONS:
+      g_value_set_pointer (value, self->add_extensions);
+      break;
+
     case PROP_CLEANUP:
       g_value_set_boxed (value, self->cleanup);
       break;
@@ -518,6 +526,12 @@ builder_manifest_set_property (GObject      *object,
       self->modules = g_value_get_pointer (value);
       break;
 
+    case PROP_ADD_EXTENSIONS:
+      g_list_free_full (self->add_extensions, g_object_unref);
+      /* NOTE: This takes ownership of the list! */
+      self->add_extensions = g_value_get_pointer (value);
+      break;
+
     case PROP_CLEANUP:
       tmp = self->cleanup;
       self->cleanup = g_strdupv (g_value_get_boxed (value));
@@ -772,6 +786,12 @@ builder_manifest_class_init (BuilderManifestClass *klass)
                                                          "",
                                                          "",
                                                          G_PARAM_READWRITE));
+  g_object_class_install_property (object_class,
+                                   PROP_ADD_EXTENSIONS,
+                                   g_param_spec_pointer ("add-extensions",
+                                                         "",
+                                                         "",
+                                                         G_PARAM_READWRITE));
   g_object_class_install_property (object_class,
                                    PROP_CLEANUP,
                                    g_param_spec_boxed ("cleanup",
@@ -956,6 +976,31 @@ builder_manifest_serialize_property (JsonSerializable *serializable,
           json_array_unref (array);
         }
 
+      return retval;
+    }
+  else if (strcmp (property_name, "add-extensions") == 0)
+    {
+      BuilderManifest *self = BUILDER_MANIFEST (serializable);
+      JsonNode *retval = NULL;
+
+      if (self->add_extensions)
+        {
+          JsonObject *object;
+          GList *l;
+
+          object = json_object_new ();
+
+          for (l = self->add_extensions; l != NULL; l = l->next)
+            {
+              BuilderExtension *e = l->data;
+              JsonNode *child = json_gobject_serialize (G_OBJECT (e));
+              json_object_set_member (object, (char *) builder_extension_get_name (e), child);
+            }
+
+          retval = json_node_init_object (json_node_alloc (), object);
+          json_object_unref (object);
+        }
+
       return retval;
     }
   else
@@ -967,6 +1012,14 @@ builder_manifest_serialize_property (JsonSerializable *serializable,
     }
 }
 
+static gint
+sort_extension (gconstpointer  a,
+                gconstpointer  b)
+{
+  return strcmp (builder_extension_get_name (BUILDER_EXTENSION (a)),
+                 builder_extension_get_name (BUILDER_EXTENSION (b)));
+}
+
 static gboolean
 builder_manifest_deserialize_property (JsonSerializable *serializable,
                                        const gchar      *property_name,
@@ -1044,6 +1097,48 @@ builder_manifest_deserialize_property (JsonSerializable *serializable,
           return TRUE;
         }
 
+      return FALSE;
+    }
+  else if (strcmp (property_name, "add-extensions") == 0)
+    {
+      if (JSON_NODE_TYPE (property_node) == JSON_NODE_NULL)
+        {
+          g_value_set_pointer (value, NULL);
+          return TRUE;
+        }
+      else if (JSON_NODE_TYPE (property_node) == JSON_NODE_OBJECT)
+        {
+          JsonObject *object = json_node_get_object (property_node);
+          g_autoptr(GHashTable) hash = g_hash_table_new_full (g_str_hash, g_str_equal, NULL, g_object_unref);
+          g_autoptr(GList) members = NULL;
+          GList *extensions;
+          GList *l;
+
+          members = json_object_get_members (object);
+          for (l = members; l != NULL; l = l->next)
+            {
+              const char *member_name = l->data;
+              JsonNode *val;
+              GObject *extension;
+
+              val = json_object_get_member (object, member_name);
+              extension = json_gobject_deserialize (BUILDER_TYPE_EXTENSION, val);
+              if (extension == NULL)
+                return FALSE;
+
+              builder_extension_set_name (BUILDER_EXTENSION (extension), member_name);
+              g_hash_table_insert (hash, (char *)builder_extension_get_name (BUILDER_EXTENSION (extension)), extension);
+            }
+
+          extensions = g_hash_table_get_values (hash);
+          g_hash_table_steal_all (hash);
+
+          extensions = g_list_sort (extensions, sort_extension);
+          g_value_set_pointer (value, extensions);
+
+          return TRUE;
+        }
+
       return FALSE;
     }
   else
@@ -1122,6 +1217,12 @@ builder_manifest_get_modules (BuilderManifest *self)
   return self->modules;
 }
 
+GList *
+builder_manifest_get_add_extensions (BuilderManifest *self)
+{
+  return self->add_extensions;
+}
+
 static const char *
 builder_manifest_get_runtime_version (BuilderManifest *self)
 {
@@ -1459,11 +1560,19 @@ builder_manifest_checksum_for_finish (BuilderManifest *self,
                                       BuilderCache    *cache,
                                       BuilderContext  *context)
 {
+  GList *l;
+
   builder_cache_checksum_str (cache, BUILDER_MANIFEST_CHECKSUM_FINISH_VERSION);
   builder_cache_checksum_strv (cache, self->finish_args);
   builder_cache_checksum_str (cache, self->command);
   builder_cache_checksum_compat_strv (cache, self->inherit_extensions);
 
+  for (l = self->add_extensions; l != NULL; l = l->next)
+    {
+      BuilderExtension *e = l->data;
+      builder_extension_checksum (e, cache, context);
+    }
+
   if (self->metadata)
     {
       GFile *base_dir = builder_context_get_base_dir (context);
@@ -2209,6 +2318,7 @@ builder_manifest_finish (BuilderManifest *self,
   g_autoptr(GPtrArray) args = NULL;
   g_autoptr(GSubprocess) subp = NULL;
   int i;
+  GList *l;
   JsonNode *node;
   JsonGenerator *generator;
 
@@ -2375,6 +2485,9 @@ builder_manifest_finish (BuilderManifest *self,
             g_ptr_array_add (args, g_strdup (self->finish_args[i]));
         }
 
+      for (l = self->add_extensions; l != NULL; l = l->next)
+        builder_extension_add_finish_args (l->data, args);
+
       g_ptr_array_add (args, g_file_get_path (app_dir));
       g_ptr_array_add (args, NULL);
 
@@ -2519,6 +2632,30 @@ builder_manifest_finish (BuilderManifest *self,
             return FALSE;
         }
 
+
+      for (l = self->add_extensions; l != NULL; l = l->next)
+        {
+          BuilderExtension *e = l->data;
+          g_autofree char *extension_metadata_name = NULL;
+          g_autoptr(GFile) metadata_extension_file = NULL;
+          g_autofree char *metadata_contents = NULL;
+
+          if (!builder_extension_is_bundled (e))
+            continue;
+
+          extension_metadata_name = g_strdup_printf ("metadata.%s", builder_extension_get_name (e));
+          metadata_extension_file = g_file_get_child (app_dir, extension_metadata_name);
+          metadata_contents = g_strdup_printf ("[Runtime]\n"
+                                               "name=%s\n"
+                                               "\n"
+                                               "[ExtensionOf]\n"
+                                               "ref=%s\n",
+                                               builder_extension_get_name (e), ref);
+          if (!g_file_set_contents (flatpak_file_get_path_cached (metadata_extension_file),
+                                    metadata_contents, strlen (metadata_contents), error))
+            return FALSE;
+        }
+
       if (!builder_context_disable_rofiles (context, error))
         return FALSE;
 
@@ -3173,3 +3310,23 @@ builder_manifest_run (BuilderManifest *self,
   /* Not reached */
   return TRUE;
 }
+
+char **
+builder_manifest_get_exclude_dirs (BuilderManifest *self)
+{
+  g_autoptr(GPtrArray) dirs = NULL;
+  GList *l;
+
+  dirs = g_ptr_array_new ();
+
+  for (l = self->add_extensions; l != NULL; l = l->next)
+    {
+      BuilderExtension *e = l->data;
+
+      if (builder_extension_is_bundled (e))
+        g_ptr_array_add (dirs, g_strdup (builder_extension_get_directory (e)));
+    }
+  g_ptr_array_add (dirs, NULL);
+
+  return (char **)g_ptr_array_free (g_steal_pointer (&dirs), FALSE);
+}

builder/builder-manifest.h

@@ -27,6 +27,7 @@
 #include "builder-options.h"
 #include "builder-module.h"
 #include "builder-cache.h"
+#include "builder-extension.h"
 
 G_BEGIN_DECLS
 
@@ -56,6 +57,7 @@ const char *    builder_manifest_get_id_platform (BuilderManifest *self);
 char *          builder_manifest_get_locale_id_platform (BuilderManifest *self);
 BuilderOptions *builder_manifest_get_build_options (BuilderManifest *self);
 GList *         builder_manifest_get_modules (BuilderManifest *self);
+GList *         builder_manifest_get_add_extensions (BuilderManifest *self);
 const char *    builder_manifest_get_branch (BuilderManifest *self);
 void            builder_manifest_set_default_branch (BuilderManifest *self,
                                                      const char *default_branch);
@@ -63,6 +65,9 @@ const char *    builder_manifest_get_collection_id (BuilderManifest *self);
 void            builder_manifest_set_default_collection_id (BuilderManifest *self,
                                                             const char      *default_collection_id);
 
+
+char **         builder_manifest_get_exclude_dirs (BuilderManifest *self);
+
 gboolean        builder_manifest_start (BuilderManifest *self,
                                         gboolean         allow_missing_runtimes,
                                         BuilderContext  *context,

doc/flatpak-manifest.xml

@@ -169,6 +169,10 @@
                     String members in the array are interpreted as the name of a separate json file that contains a module.
                     See below for details.</para></listitem>
                 </varlistentry>
+                <varlistentry>
+                    <term><option>add-extensions</option> (objects)</term>
+                    <listitem><para>This is a dictionary of extension objects. The key is the name of the extension. See below for details.</para></listitem>
+                </varlistentry>
                 <varlistentry>
                     <term><option>cleanup</option> (array of strings)</term>
                     <listitem><para>An array of file patterns that should be removed at the end.
@@ -276,6 +280,36 @@
                 </varlistentry>
             </variablelist>
         </refsect2>
+        <refsect2>
+            <title>Extension</title>
+            <para>
+              Extension define extension points in the app/runtime that can be implemented by extensions, supplying extra files
+              which are available during runtime..
+            </para>
+            <para>
+                These are the properties that are accepted:
+            </para>
+            <variablelist>
+                <varlistentry>
+                    <term><option>directory</option> (string)</term>
+                    <listitem><para>The directory where the extension is mounted.</para></listitem>
+                </varlistentry>
+                <varlistentry>
+                    <term><option>bundle</option> (boolean)</term>
+                    <listitem><para>If this is true, then the data
+                    created in the extension directory is omitted from
+                    the result, and instead packaged in a separate
+                    extension..</para></listitem>
+                </varlistentry>
+            </variablelist>
+            <para>
+              Additionally the standard flatpak extension properies
+              are supported, and put directly into the metadata file:
+              autodelete, no-autodownload, subdirectories,
+              add-ld-path, download-if, enable-if, merge-dirs,
+              subdirectory-suffix, version, versions.
+            </para>
+        </refsect2>
         <refsect2>
             <title>Module</title>
             <para>