[gnome-software: 16/25] gs-odrs-provider: Refactor parsing function

[Philip Withnall <pwithnall src gnome org>]

commit 08f808e06c6727aa6e16a7ccf351efcc4481a2c9
Author: Philip Withnall <pwithnall endlessos org>
Date:   Fri Feb 25 14:31:21 2022 +0000

    gs-odrs-provider: Refactor parsing function
    
    Refactor the parsing function so it can take a `JsonParser` object,
    rather than always constructing one internally.
    
    Different callers get access to their data in different ways. This will
    allow us to use `json_parser_load*()` methods which are more appropriate
    to each caller.
    
    In particular, this will allow JSON to be parsed chunk-wise as it’s
    downloaded from the network, rather than downloading into a huge
    allocated buffer and then parsing that buffer.
    
    This introduces no functional changes.
    
    Signed-off-by: Philip Withnall <pwithnall endlessos org>
    
    Helps: #1658

 lib/gs-odrs-provider.c | 116 +++++++++++++++++++++++++++++++++++--------------
 1 file changed, 83 insertions(+), 33 deletions(-)
---
diff --git a/lib/gs-odrs-provider.c b/lib/gs-odrs-provider.c
index 0c98b5089..de8290443 100644
--- a/lib/gs-odrs-provider.c
+++ b/lib/gs-odrs-provider.c
@@ -254,44 +254,20 @@ gs_odrs_provider_parse_review_object (JsonObject *item)
        return rev;
 }
 
+/* json_parser_load*() must have been called on @json_parser before calling
+ * this function. */
 static GPtrArray *
 gs_odrs_provider_parse_reviews (GsOdrsProvider  *self,
-                                const gchar     *data,
-                                gssize           data_len,
+                                JsonParser      *json_parser,
                                 GError         **error)
 {
        JsonArray *json_reviews;
        JsonNode *json_root;
        guint i;
-       g_autoptr(JsonParser) json_parser = NULL;
        g_autoptr(GHashTable) reviewer_ids = NULL;
        g_autoptr(GPtrArray) reviews = NULL;
        g_autoptr(GError) local_error = NULL;
 
-       /* nothing */
-       if (data == NULL) {
-               if (!g_network_monitor_get_network_available (g_network_monitor_get_default ()))
-                       g_set_error_literal (error,
-                                            GS_ODRS_PROVIDER_ERROR,
-                                            GS_ODRS_PROVIDER_ERROR_NO_NETWORK,
-                                            "server couldn't be reached");
-               else
-                       g_set_error_literal (error,
-                                            GS_ODRS_PROVIDER_ERROR,
-                                            GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
-                                            "server returned no data");
-               return NULL;
-       }
-
-       /* parse the data and find the array or ratings */
-       json_parser = json_parser_new_immutable ();
-       if (!json_parser_load_from_data (json_parser, data, data_len, &local_error)) {
-               g_set_error (error,
-                            GS_ODRS_PROVIDER_ERROR,
-                            GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
-                            "Error parsing ODRS data: %s", local_error->message);
-               return NULL;
-       }
        json_root = json_parser_get_root (json_parser);
        if (json_root == NULL) {
                g_set_error_literal (error,
@@ -716,6 +692,7 @@ gs_odrs_provider_fetch_reviews_for_app_async (GsOdrsProvider      *self,
        g_autoptr(GFile) cachefn_file = NULL;
        g_autoptr(GPtrArray) reviews = NULL;
        g_autoptr(JsonBuilder) builder = NULL;
+       g_autoptr(JsonParser) json_parser = NULL;
        g_autoptr(JsonGenerator) json_generator = NULL;
        g_autoptr(JsonNode) json_root = NULL;
        g_autoptr(SoupMessage) msg = NULL;
@@ -752,10 +729,30 @@ gs_odrs_provider_fetch_reviews_for_app_async (GsOdrsProvider      *self,
 
                g_debug ("got review data for %s from %s",
                         gs_app_get_id (app), cachefn);
-               reviews = gs_odrs_provider_parse_reviews (self,
-                                                         g_mapped_file_get_contents (mapped_file),
-                                                         g_mapped_file_get_length (mapped_file),
-                                                         &local_error);
+
+               /* nothing */
+               if (g_mapped_file_get_contents (mapped_file) == NULL) {
+                       g_task_return_new_error (task,
+                                                GS_ODRS_PROVIDER_ERROR,
+                                                GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+                                                "server returned no data");
+                       return;
+               }
+
+               /* parse the data and find the array of ratings */
+               json_parser = json_parser_new_immutable ();
+               if (!json_parser_load_from_data (json_parser,
+                                                g_mapped_file_get_contents (mapped_file),
+                                                g_mapped_file_get_length (mapped_file),
+                                                &local_error)) {
+                       g_task_return_new_error (task,
+                                                GS_ODRS_PROVIDER_ERROR,
+                                                GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+                                                "Error parsing ODRS data: %s", local_error->message);
+                       return;
+               }
+
+               reviews = gs_odrs_provider_parse_reviews (self, json_parser, &local_error);
                if (reviews == NULL) {
                        g_task_return_error (task, g_steal_pointer (&local_error));
                } else {
@@ -836,7 +833,32 @@ gs_odrs_provider_fetch_reviews_for_app_async (GsOdrsProvider      *self,
                return;
        }
 
-       reviews = gs_odrs_provider_parse_reviews (self, downloaded_data, downloaded_data_length, 
&local_error);
+       /* nothing */
+       if (downloaded_data == NULL) {
+               if (!g_network_monitor_get_network_available (g_network_monitor_get_default ()))
+                       g_task_return_new_error (task,
+                                                GS_ODRS_PROVIDER_ERROR,
+                                                GS_ODRS_PROVIDER_ERROR_NO_NETWORK,
+                                                "server couldn't be reached");
+               else
+                       g_task_return_new_error (task,
+                                                GS_ODRS_PROVIDER_ERROR,
+                                                GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+                                                "server returned no data");
+               return;
+       }
+
+       /* parse the data and find the array of ratings */
+       json_parser = json_parser_new_immutable ();
+       if (!json_parser_load_from_data (json_parser, downloaded_data, downloaded_data_length, &local_error)) 
{
+               g_task_return_new_error (task,
+                                        GS_ODRS_PROVIDER_ERROR,
+                                        GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+                                        "Error parsing ODRS data: %s", local_error->message);
+               return;
+       }
+
+       reviews = gs_odrs_provider_parse_reviews (self, json_parser, &local_error);
        if (reviews == NULL) {
                g_task_return_error (task, g_steal_pointer (&local_error));
                return;
@@ -1825,11 +1847,13 @@ gs_odrs_provider_add_unvoted_reviews (GsOdrsProvider  *self,
        gsize downloaded_data_length;
        g_autofree gchar *uri = NULL;
        g_autoptr(GHashTable) hash = NULL;
+       g_autoptr(JsonParser) json_parser = NULL;
        g_autoptr(GPtrArray) reviews = NULL;
        g_autoptr(SoupMessage) msg = NULL;
 #if SOUP_CHECK_VERSION(3, 0, 0)
        g_autoptr(GBytes) bytes = NULL;
 #endif
+       g_autoptr(GError) local_error = NULL;
 
        /* create the GET data *with* the machine hash so we can later
         * review the application ourselves */
@@ -1861,7 +1885,33 @@ gs_odrs_provider_add_unvoted_reviews (GsOdrsProvider  *self,
                return FALSE;
        }
        g_debug ("odrs returned: %.*s", (gint) downloaded_data_length, (const gchar *) downloaded_data);
-       reviews = gs_odrs_provider_parse_reviews (self, downloaded_data, downloaded_data_length, error);
+
+       /* nothing */
+       if (downloaded_data == NULL) {
+               if (!g_network_monitor_get_network_available (g_network_monitor_get_default ()))
+                       g_set_error_literal (error,
+                                            GS_ODRS_PROVIDER_ERROR,
+                                            GS_ODRS_PROVIDER_ERROR_NO_NETWORK,
+                                            "server couldn't be reached");
+               else
+                       g_set_error_literal (error,
+                                            GS_ODRS_PROVIDER_ERROR,
+                                            GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+                                            "server returned no data");
+               return FALSE;
+       }
+
+       /* parse the data and find the array of ratings */
+       json_parser = json_parser_new_immutable ();
+       if (!json_parser_load_from_data (json_parser, downloaded_data, downloaded_data_length, &local_error)) 
{
+               g_set_error (error,
+                            GS_ODRS_PROVIDER_ERROR,
+                            GS_ODRS_PROVIDER_ERROR_PARSING_DATA,
+                            "Error parsing ODRS data: %s", local_error->message);
+               return FALSE;
+       }
+
+       reviews = gs_odrs_provider_parse_reviews (self, json_parser, error);
        if (reviews == NULL)
                return FALSE;