gs-plugin-appimage.c

/* GNOME Software AppImage plugin
 * Licensing to be determined (MIT like AppImageKit or GPLv2 like GNOME Software)
 */

#include <gnome-software.h>
#include <appimage/appimage.h> // From https://github.com/AppImage/AppImageKit
#include <sys/stat.h>

void
gs_plugin_initialize (GsPlugin *plugin)
{
    g_debug("AppImage gs_plugin_initialize");
    gs_plugin_add_rule (plugin, GS_PLUGIN_RULE_RUN_BEFORE, "appstream");
    
    
    /* prioritize over packages */
    gs_plugin_add_rule (plugin, GS_PLUGIN_RULE_BETTER_THAN, "packagekit");
}

/* Claim AppImages that should be handled by this plugin.
 * hughsie: gnome-software doesn't understand what a desktop file is but appstrem-glib does, so we need
 * to let appstream-glib discover them and then adopt them in the plugin
 */
void
gs_plugin_adopt_app (GsPlugin *plugin, GsApp *app)
{
    if (gs_app_get_bundle_kind (app) == AS_BUNDLE_KIND_APPIMAGE)
        gs_app_set_management_plugin (app, gs_plugin_get_name (plugin));
}

/* Launch AppImages
 * QUESTION: Do I even need to do something special? Why doesn't it just launch the desktop file?
 * hughsie: don't implement gs_plugin_launch and see if it works (it should)
 */
gboolean
gs_plugin_launch (GsPlugin *plugin,
                  GsApp *app,
                  GCancellable *cancellable,
                  GError **error)
{
    
    if (gs_app_get_bundle_kind (app) == AS_BUNDLE_KIND_APPIMAGE) {
        g_debug("AppImage shall be launched");
        
        g_autofree gchar *md5 = appimage_get_md5(g_file_get_path (gs_app_get_local_file (app)));
        g_autofree gchar *partial_path = g_strdup_printf("applications/appimagekit_%s-%s", md5, "*");
        g_autofree const gchar *data_home = g_get_user_data_dir();
        g_autofree gchar *appimage_integrated_desktop_file_path = g_build_filename(data_home, partial_path, NULL);
        
        
        if (g_file_test (appimage_integrated_desktop_file_path, G_FILE_TEST_EXISTS))
        {
            g_debug("AppImage is already integrated at %s", appimage_integrated_desktop_file_path);
        } else {
            g_debug("AppImage is not integrated yet");
        }
        return TRUE;
    } else {
        g_debug("Not an AppImage");
        return FALSE; // FIXME: Proper error handling using GError
    }
    
}



/*
 * Handle AppImages "opened" with GNOME Software
 * This works; it does show the product detail page when launched like this:
 * XDG_DATA_DIRS=install/share:$XDG_DATA_DIRS ../install/bin/gnome-software --verbose --local-filename=/isodevice/Applications/XChat-2.8.8-x86_64.AppImage 2>&1 | grep AppImage
 * 
 */

gboolean
gs_plugin_file_to_app (GsPlugin *plugin,
                       GsAppList *list,
                       GFile *file,
                       GCancellable *cancellable,
                       GError **error)
{
    g_debug("AppImage gs_plugin_url_to_app");
    g_debug("file: %s", g_file_get_path(file));
    
    
    int appimage_type = appimage_get_type(g_file_get_path(file), TRUE);
    g_debug("AppImage type: %i", appimage_type);
    
    /* Error if we cannot determine the type of the AppImage */
    if(appimage_type <0) {
        return FALSE;
    }
    
    /* Extract the desktop file from the AppImage */
    char** files = appimage_list_files(g_file_get_path(file));
    g_autofree gchar *desktop_file = NULL;
    gchar *extracted_desktop_file = "/tmp/gs-plugin-appimage.desktop";
    int i = 0;
    for (; files[i] != NULL ; i++) {
        // g_debug("AppImage file: %s", files[i]);
        if (g_str_has_suffix (files[i],".desktop")) {
            desktop_file = files[i];
            g_debug("AppImage desktop file: %s", desktop_file);
            break;
        }
    }
    /* Exit if we cannot find the desktop file */
    if(desktop_file == NULL) {
        g_debug("AppImage desktop file not found");
        appimage_string_list_free(files);
        return FALSE;
    }
    /* Extract desktop file to temporary location */
    appimage_extract_file_following_symlinks(g_file_get_path(file), desktop_file,
                                             extracted_desktop_file);
    
    /* Load contents of desktop file */
    gboolean success = FALSE;
    GKeyFile* key_file_structure =  g_key_file_new();
    
    /* QUESTION: Do we need to load desktop files like this?
     * hughsie: appstream-glib can do that work
     */
    g_debug("Loading AppImage desktop file from %s", extracted_desktop_file);
    success = g_key_file_load_from_file(key_file_structure, extracted_desktop_file, G_KEY_FILE_KEEP_COMMENTS | G_KEY_FILE_KEEP_TRANSLATIONS, NULL);
    if (!success) {
        g_debug("AppImage desktop file could not be loaded");
        appimage_string_list_free(files);
        return FALSE;
    } else {
        g_debug("Loaded AppImage desktop file");  // QUESTION: Can we directly gs_app_new() from this? hughsie: use appstream-glib
    }
    
    /* TODO: AppStream
     *    Save an AppStream-format XML file in either /usr/share/app-info/xmls/, /var/cache/app-info/xmls/ or ~/.local/share/app-info/xmls/. GNOME Software will immediately notice any new files, or changes to existing files as it has set up the various inotify watches.
     *    
     *    QUESTION: Do we need to copy XML there for AppImages that are not integrated into the system? 
     *    Can we load in data from an xml file which we delete immediately afterwards?
     *    Because we don't want to litter the system with XML files.
     *    hughsie: Don't need to copy; just use the helpers in gs-appstream.c; 
     *    e.g. the Flatpak plugin loads the AppStream xml from a nonstandard path
     * 
     *    QUESTION: If we need to ensure that our AppStream information is not mixed with AppStream 
     *    information from other locations or from version to version of an application, is it OK to place it in
     *    /home/me/.local/share/app-info/xmls/appimagekit_98080cfc981c9098c6a5e41794add640-deepin-screenshot.appdata.xml
     *    hughsie: the filename is almost unimportant, it's the <id> that has to match
     * 
     *    QUESTION: If we have appimagekit_98080cfc981c9098c6a5e41794add640-deepin-screenshot.desktop in one of 
     *    the well-known locations for desktop files, will it automatically be associated with the AppStream metadata from above?
     *    hughsie: the filename is almost unimportant, it's the <id> that has to match
     *    
     *    QUESTION: Is the AppStream ID the same as the gs ID?
     *    hughsie: In most cases, yes. The appstream file can also have a <launchable> tab pointing to the desktop file.
     *    If there's no launchable then we use a heuristic to try and create one
     *    
     *    QUESTION: Is there a screenshot where i could see the effect of using different IDs for gs_app_new() vs. gs_app_set_branch()?
     *    hughsie: Not really, but you can use gnome-software-cmd like this: /usr/libexec/gnome-software-cmd search --refine-flags=icon --show-results
     *    
     *    I see:
     *    08:20:32:0181 Gs  searching appstream for user / * / * / desktop / appimagekit_98080cfc981c9098c6a5e41794add640-deepin-screenshot.desktop / *
     * 
     *    QUESTION: Should we have appimaged (also) integrate AppStream files to ~/.local/share/app-info/xmls/?
     *    hughsie: I think using reverse DNS style IDs everywhere is a very good idea; I also think it's too early to optimise anything
     */
    
         
    g_autofree gchar *md5 = appimage_get_md5(g_file_get_path (file));

/* FIXME: This block is commented out because it crashes.
 * I suspect it has to do with some g_free(), g_autofree, g_autoptr and/or appimage_string_list_free()
 * stuff. Any help greatly appreciated.

    // QUESTION: Why does glib not have a str_replace()? hughsie: If you have a GString, can use as_utils_string_replace()
    g_autoptr(GString) appstream_filename = g_string_new(g_path_get_basename(desktop_file));
    as_utils_string_replace(appstream_filename, ".desktop", ".metainfo.xml");
    gchar *extracted_appstream_file = g_strconcat(g_get_user_data_dir(), "/app-info/xmls/", "appimagekit_", md5, "-", g_string_free(appstream_filename, FALSE), NULL);
    // g_free(appstream_filename); // Would lead to a crash
    g_debug("AppImage AppStream file to be extracted to: %s", extracted_appstream_file);
    
    // Extract the AppStream file from the AppImage
    files = appimage_list_files(g_file_get_path(file));
    g_autofree gchar *appstream_file = NULL;
    i = 0;
    for (; files[i] != NULL ; i++) {
        // g_debug("AppImage file: %s", files[i]);
        if (g_str_has_suffix (files[i],".metainfo.xml")) {
            appstream_file = files[i];
            g_debug("AppImage AppStream file: %s", appstream_file);
            break;
        }
    }

    if(appstream_file == NULL) {
        g_debug("AppImage AppStream file not found in AppImage; hence not extracting");
        appimage_string_list_free(files);
    } else {
        // Extract AppStream file
        g_debug("AppImage extracting AppStream file");
        appimage_extract_file_following_symlinks(g_file_get_path(file), appstream_file,
                                                 extracted_appstream_file);
    }
    
    g_free(extracted_appstream_file); // FIXME: SOMETIMES crashes around here, regardless of this being called or not
*/

    g_autofree gchar *fn = NULL;
    g_autoptr(GsApp) app = NULL;
    g_autoptr(AsIcon) icon = NULL;
    
    app = gs_app_new ("NULL"); // NOTE: We set the ID down below, including the md5 from appimage_get_md5. hughsie recommends reverse DNS, and it should match the desktop file and the id in the AppStream XML
    gs_app_set_scope (app, AS_APP_SCOPE_USER);
    gs_app_set_management_plugin (app, "appimage");
    gs_app_set_kind (app, AS_APP_KIND_DESKTOP);
    gs_app_set_bundle_kind (app, AS_BUNDLE_KIND_APPIMAGE);
    gs_app_set_local_file (app, file);
    // gs_app_add_quirk (app, AS_APP_QUIRK_PROVENANCE); // QUESTION: How to mark "3rd party"? hughsie: PROVENANCE usually means the opposite, e.g. it's from the distro
    // gs_app_set_state (app, AS_APP_STATE_AVAILABLE_LOCAL);
    gs_app_set_name (app, GS_APP_QUALITY_NORMAL, g_key_file_get_value(key_file_structure, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_NAME, NULL));
    gs_app_set_summary (app, GS_APP_QUALITY_NORMAL, g_key_file_get_value(key_file_structure, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_COMMENT, NULL));
    gs_app_set_description (app, GS_APP_QUALITY_NORMAL, g_key_file_get_value(key_file_structure, G_KEY_FILE_DESKTOP_GROUP, G_KEY_FILE_DESKTOP_KEY_COMMENT, NULL));
    
    /* these are all optional, but make details page look better */
    gs_app_set_version (app, g_key_file_get_value(key_file_structure, G_KEY_FILE_DESKTOP_GROUP, "X-AppImage-Version", NULL));
    
    /* Get the size of the AppImage on disk */
    struct stat st;
    if (lstat(g_file_get_path(file), &st) == -1) {
        g_debug("Could not determine AppImage file size");
        return FALSE;
    }
    gs_app_set_size_installed (app, st.st_size);
    gs_app_set_size_download (app, st.st_size);
    
    /* Check if this AppImage is already integrated in the system in which case we treat it as "installed */
    
    g_autofree gchar *partial_path = g_strdup_printf("applications/appimagekit_%s-%s", md5, g_path_get_basename(desktop_file));
    g_autofree gchar *appimage_integrated_desktop_file_path = g_build_filename(g_get_user_data_dir(), partial_path, NULL);
    g_autofree const gchar *appimage_id = g_path_get_basename(partial_path);
    gs_app_set_id (app, appimage_id); // This makes it use the desktop file and icon already integrated into the system
    
    if (g_file_test (appimage_integrated_desktop_file_path, G_FILE_TEST_EXISTS))
    {
        g_debug("AppImage is already integrated at %s", appimage_integrated_desktop_file_path);
        gs_app_set_state (app, AS_APP_STATE_INSTALLED);
    } else {
        g_debug("AppImage is not integrated yet");
        gs_app_set_state (app, AS_APP_STATE_AVAILABLE_LOCAL);
    }
    
    g_debug("AppImage gs_app_is_installed: %i", gs_app_is_installed (app));
    gs_app_set_origin (app, "AppImage");
    
    // QUESTION: "Install" doesn't really cut it. For AppImages, we would want 
    // "Move to /Applications", "Move to $HOME/Applications", etc. Is there a way to cusomize this?
    // hughsie: In gnome-software they'd be different "scope" and therefore different GsApp
    // others want the same kind of feature, so it's probably something we ought to support
    
    /* return new app */
    gs_app_list_add (list, app);
    
    g_key_file_free(key_file_structure);
    // appimage_string_list_free(files); // FIXME: This results in a segfault!
    
    return TRUE;
}



/* 
 * 
 * This works; it DOES show up in the installed list!
 * 
 * QUESTION: How can I achieve a similar thing for all the desktop files of already integrated AppImages that show up like this:
 * 
 * 08:25:05:0456 As  adding existing file: /home/me/.local/share/applications/appimagekit_96c121fd6971e6073de75aa0cdad64dd-AppImageUpdate.desktop
 * 08:25:05:0456 As  adding existing file: /home/me/.local/share/applications/appimagekit_d6d51dc8061f0166e11ecd040af70e8e-AppImageUpdate.desktop
 * 
 * 08:26:09:0696 GsPluginPackageKit ignoring /usr/share/applications/appimagekit_96c121fd6971e6073de75aa0cdad64dd-AppImageUpdate.desktop as does not exist
 * 08:26:09:0696 GsPluginPackageKit ignoring /usr/share/applications/appimagekit_d6d51dc8061f0166e11ecd040af70e8e-AppImageUpdate.desktop as does not exist
 * 
 * 08:26:13:0491 Gs  app invalid as state unknown user / * / * / desktop / appimagekit_96c121fd6971e6073de75aa0cdad64dd-AppImageUpdate.desktop / *
 * 08:26:13:0491 Gs  app invalid as state unknown user / * / * / desktop / appimagekit_d6d51dc8061f0166e11ecd040af70e8e-AppImageUpdate.desktop / *
 * 
 * QUESTION: What do I have to do in order to make these show up as installed? 
 * QUESTION: Why does it say "ignoring... as does not exist"? 
 * QUESTION: What does "app invalid as state unknown user" mean? Probably I have to set them to AS_APP_STATE_INSTALLED, but how?
 * 
 */

gboolean
gs_plugin_add_installed (GsPlugin *plugin,
                         GsAppList *list,
                         GCancellable *cancellable,
                         GError **error)
{
    g_debug("AppImage gs_plugin_add_installed");
    
    g_autofree gchar *fn = NULL;
    g_autoptr(GsApp) app = NULL;
    g_autoptr(AsIcon) icon = NULL;
    
    // One entry will show up in the list of installed files for each DIFFERENTLY NAMED desktop file
    // "System appstream" will be searched for metadata with matching desktop file names
    app = gs_app_new ("aaatestapp.desktop"); // "Launch" button only available if ID is passed in
    gs_app_set_scope (app, AS_APP_SCOPE_USER); // TODO: Distinguish system-wide AppImages. Those which are read-only for the current user?
    gs_app_set_management_plugin (app, "appimage");
    gs_app_set_kind (app, AS_APP_KIND_DESKTOP);
    gs_app_set_bundle_kind (app, AS_BUNDLE_KIND_APPIMAGE);
    gs_app_set_state (app, AS_APP_STATE_INSTALLED);
    gs_app_set_name (app, GS_APP_QUALITY_NORMAL, "AAATestApp 1.2.3a"); // QUESTION: How to handle multiple versions properly?
    gs_app_set_summary (app, GS_APP_QUALITY_NORMAL, "A teaching application");
    gs_app_set_description (app, GS_APP_QUALITY_NORMAL,
                            "AAATestApp is the name of an application.\n\n"
                            "It can be used to demo some of our features");
    
    /* create a stock icon which will be loaded by the 'icons' plugin
     * NOTE: Without doing this, it will NOT show up in the list of installed files.
     * QUESTION: Is this intentional? hughsie: yes, an app needs an icon
     */
    icon = as_icon_new ();
    as_icon_set_kind (icon, AS_ICON_KIND_STOCK);
    as_icon_set_name (icon, "application-x-executable");
    gs_app_add_icon (app, icon);
    
    /* return new app */
    gs_app_list_add (list, app);
    
    return TRUE;
}

/*
 * QUESTION: Can plugins have their own settings, and where would the GUI for these be?
 * hughsie: There is a gsetting key to be shared by plugins for this
 * 
 * QUESTION: How do I populate the list of installable apps?
 * hughsie: You just return the GsApps when the frontend wants results;
 * typically that'll be add_popular, add_featured or search()
 * 
 * QUESTION: I assume it uses the XDG desktop categories?
 * hughsie: It does; just make sure it has the right "categories"
 * 
 * QUESTION: How to make all of https://appimage.github.io/feed.json
 * show up in gs in the respective categories?
 * hughsie: Is that data available as appstream xml too? That's the easiest way; 
 * otherwise you have to handle the add_categories()
 * and add_categories_ap()
 * 
 * QUESTION: do you have a minimal viable example of the kind of distro appstream xml needed that you were referring to?
 * hughsie: yaml is supported, but it's had nowhere near the memory optimisation work
 * it's the same XML as an appdata file, wraped up in <components>
 * 
 * Just return them as results for the various query methods
 * e.g. we never show "all" the apps that can be installed
 * 
 * What most plugins do is use gs_plugin_search() and then if they need some shared resource
 * call into some plugin_specific_ensure() thing to open store, parse xml etc.,
 * e.g. not do it in gs_plugin_setup() if it's going to take time
 * 
 */