* fix "Keys and values must be strings" error

* delete the temporary file if we get a printing error
* add better error logging in case of printing error

git-svn-id: https://xpra.org/svn/Xpra/trunk@14202 3bb7dfac-3a0b-4e04-842a-767bc560f471

src/xpra/net/file_transfer.py

@@ -319,7 +319,14 @@ def delfile():
             printlog.error(" printers available: %s", csv(printers.keys()) or "none")
             delfile()
             return
-        job = print_files(printer, [filename], title, options)
+        try:
+            job = print_files(printer, [filename], title, options)
+        except Exception as e:
+            printlog("print_files%s", (printer, [filename], title, options), exc_info=True)
+            printlog.error("Error: cannot print file '%s'", os.path.basename(filename))
+            printlog.error(" %s", e)
+            delfile()
+            return
         printlog("printing %s, job=%s", filename, job)
         if job<=0:
             printlog("printing failed and returned %i", job)

src/xpra/platform/pycups_printing.py

@@ -402,7 +402,7 @@ def print_files(printer, filenames, title, options):
         raise Exception("invalid printer: '%s'" % printer)
     log("pycups.print_files%s", (printer, filenames, title, options))
     actual_options = DEFAULT_CUPS_OPTIONS.copy()
-    actual_options.update(options)
+    actual_options.update(dict(str(k),str(v) for k,v in options.items()))
     if SIMULATE_PRINT_FAILURE:
         log.warn("Warning: simulating print failure")
         conn = None