From 28a6267c056d43cdbf8cd3e10e69d8ab113e74f8 Mon Sep 17 00:00:00 2001

From: Michal Srb <michal@redhat.com>

Date: Tue, 7 Sep 2021 21:31:21 +0200

Subject: [PATCH] [rhbz] Retry XML-RPC calls when uploading attachments

If there is a bot that automatically modifies newly opened bugs, then

it can lead to "query serialization error" from Bugzilla. Retry should

help us here.

Signed-off-by: Michal Srb <michal@redhat.com>

---

 src/lib/abrt_xmlrpc.c     | 34 ++++++++++++++++++++++++++++++++++

 src/lib/abrt_xmlrpc.h     |  5 +++++

 src/lib/libreport-web.sym |  1 +

 src/plugins/rhbz.c        |  4 +++-

 4 files changed, 43 insertions(+), 1 deletion(-)

diff --git a/src/lib/abrt_xmlrpc.c b/src/lib/abrt_xmlrpc.c

index 7cac9253..4c3b469a 100644

--- a/src/lib/abrt_xmlrpc.c

+++ b/src/lib/abrt_xmlrpc.c

@@ -16,6 +16,7 @@

     with this program; if not, write to the Free Software Foundation, Inc.,

     51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

 */

+#include <unistd.h>

 #include "internal_libreport.h"

 #include "abrt_xmlrpc.h"

 #include "proxies.h"

@@ -301,3 +302,36 @@ xmlrpc_value *abrt_xmlrpc_call(struct abrt_xmlrpc *ax,

     return result;

 }

+

+/* die eventually or return expected results; retry up to 5 times if the error is known */

+xmlrpc_value *abrt_xmlrpc_call_with_retry(const char *fault_substring,

+                                          struct abrt_xmlrpc *ax,

+                                          const char *method,

+                                          const char *format, ...)

+{

+    int retry_counter = 0;

+    xmlrpc_env env;

+

+    va_list args;

+

+    do {

+        // sleep, if this is not the first try;

+        // sleep() can be interrupted, but that's not a big deal here

+        if (retry_counter)

+            sleep(retry_counter);

+

+        va_start(args, format);

+        xmlrpc_value *result = abrt_xmlrpc_call_full_va(&env, ax, method, format, args);

+        va_end(args);

+

+        if (!env.fault_occurred)

+            return result;  // success!

+

+        if (env.fault_string && !strstr(env.fault_string, fault_substring)) {

+            // unknown error, don't bother retrying...

+            abrt_xmlrpc_die(&env;;

+        }

+    } while (++retry_counter <= 5);

+

+    abrt_xmlrpc_die(&env;;

+}

diff --git a/src/lib/abrt_xmlrpc.h b/src/lib/abrt_xmlrpc.h

index 31768ffc..8ddcfc54 100644

--- a/src/lib/abrt_xmlrpc.h

+++ b/src/lib/abrt_xmlrpc.h

@@ -63,6 +63,11 @@ xmlrpc_value *abrt_xmlrpc_call_params(xmlrpc_env *env, struct abrt_xmlrpc *ax,

 xmlrpc_value *abrt_xmlrpc_call_full(xmlrpc_env *enf, struct abrt_xmlrpc *ax,

                                    const char *method, const char *format, ...);

+xmlrpc_value *abrt_xmlrpc_call_with_retry(const char *fault_substring,

+                                          struct abrt_xmlrpc *ax,

+                                          const char *method,

+                                          const char *format, ...);

+

 #ifdef __cplusplus

 }

 #endif

diff --git a/src/lib/libreport-web.sym b/src/lib/libreport-web.sym

index 44f5244d..9ab88d3e 100644

--- a/src/lib/libreport-web.sym

+++ b/src/lib/libreport-web.sym

@@ -51,6 +51,7 @@ global:

     abrt_xmlrpc_call;

     abrt_xmlrpc_call_params;

     abrt_xmlrpc_call_full;

+    abrt_xmlrpc_call_with_retry;

     /* internal_libreport.h - these symbols are only to be used by libreport developers */

     libreport_trim_all_whitespace;

diff --git a/src/plugins/rhbz.c b/src/plugins/rhbz.c

index 0dae1e93..f252f914 100644

--- a/src/plugins/rhbz.c

+++ b/src/plugins/rhbz.c

@@ -643,8 +643,10 @@ int rhbz_attach_blob(struct abrt_xmlrpc *ax, const char *bug_id,

      *   i -> integer, single argument (int value)

      *   6 -> base64,  two arguments (char* plain data which will be encoded by xmlrpc-c to base64,

      *                                size_t number of bytes to encode)

+     *

+     * Retry if another user/bot attempted to change the same data.

      */

-    result = abrt_xmlrpc_call(ax, "Bug.add_attachment", "{s:(s),s:s,s:s,s:s,s:6,s:i}",

+    result = abrt_xmlrpc_call_with_retry("query serialization error", ax, "Bug.add_attachment", "{s:(s),s:s,s:s,s:s,s:6,s:i}",

                 "ids", bug_id,

                 "summary", fn,

                 "file_name", filename,

-- 

2.31.1