serialize amounts as string instead of an object

src/json/json_helper.c

@@ -35,25 +35,15 @@
 json_t *
 TALER_JSON_from_amount (const struct TALER_Amount *amount)
 {
-  json_t *j;
+  char *amount_str = TALER_amount_to_string (amount);
+
+  GNUNET_assert (NULL != amount_str);
 
-  if ( (amount->value != (uint64_t) ((json_int_t) amount->value)) ||
-       (0 > ((json_int_t) amount->value)) )
   {
-    /* Theoretically, json_int_t can be a 32-bit "long", or we might
+    json_t *j = json_string (amount_str);
-       have a 64-bit value which converted to a 63-bit signed long
+    GNUNET_free (amount_str);
-       long causes problems here.  So we check.  Note that depending
-       on the platform, the compiler may be able to statically tell
-       that at least the first check is always false. */
-    GNUNET_break (0);
-    return NULL;
-  }
-  j = json_pack ("{s:s, s:I, s:I}",
-                 "currency", amount->currency,
-                 "value", (json_int_t) amount->value,
-                 "fraction", (json_int_t) amount->fraction);
-  GNUNET_assert (NULL != j);
     return j;
+  }
 }
 
 
@@ -93,6 +83,20 @@ parse_amount (void *cls,
   json_int_t fraction;
   const char *currency;
 
+  if (json_is_string (root))
+  {
+    if (GNUNET_OK !=
+        TALER_string_to_amount (json_string_value (root), r_amount))
+    {
+      GNUNET_break_op (0);
+      return GNUNET_SYSERR;
+    }
+    return GNUNET_OK;
+  }
+
+  /* Also allow the legacy { value, fraction, currency} format.
+     This might be removed in the future. */
+
   memset (r_amount,
           0,
           sizeof (struct TALER_Amount));
@@ -179,6 +183,17 @@ parse_amount_nbo (void *cls,
   json_int_t fraction;
   const char *currency;
 
+  if (json_is_string (root))
+  {
+    if (GNUNET_OK !=
+        TALER_string_to_amount_nbo (json_string_value (root), r_amount))
+    {
+      GNUNET_break_op (0);
+      return GNUNET_SYSERR;
+    }
+    return GNUNET_OK;
+  }
+
   memset (&amount,
           0,
           sizeof (struct TALER_Amount));

src/json/test_json.c

@@ -36,14 +36,14 @@ test_amount ()
   struct TALER_Amount a1;
   struct TALER_Amount a2;
   struct GNUNET_JSON_Specification spec[] = {
-    TALER_JSON_spec_amount (NULL, &a2),
+    TALER_JSON_spec_amount ("amount", &a2),
     GNUNET_JSON_spec_end()
   };
 
   GNUNET_assert (GNUNET_OK ==
 		 TALER_string_to_amount ("EUR:4.3",
 					 &a1));
-  j = TALER_JSON_from_amount (&a1);
+  j = json_pack("{s:o}", "amount", TALER_JSON_from_amount (&a1));
   GNUNET_assert (NULL != j);
   GNUNET_assert (GNUNET_OK ==
 		 GNUNET_JSON_parse (j, spec,