-code cleanupv0.9.3-dev.1

18 files changed, 144 insertions, 308 deletions

diff --git a/src/backend/taler-merchant-httpd_helper.c b/src/backend/taler-merchant-httpd_helper.c
index 75639af6..48a42f40 100644
--- a/src/backend/taler-merchant-httpd_helper.c
+++ b/src/backend/taler-merchant-httpd_helper.c
@@ -34,7 +34,7 @@ TMH_cmp_wire_account (
   const struct TMH_WireMethod *wm)
 {
   const char *credit_facade_url = NULL;
-  json_t *credit_facade_credentials = NULL;
+  const json_t *credit_facade_credentials = NULL;
   const char *uri;
   struct GNUNET_JSON_Specification ispec[] = {
     GNUNET_JSON_spec_string ("payto_uri",
@@ -44,8 +44,8 @@ TMH_cmp_wire_account (
                                &credit_facade_url),
       NULL),
     GNUNET_JSON_spec_mark_optional (
-      GNUNET_JSON_spec_json ("credit_facade_credentials",
-                             &credit_facade_credentials),
+      GNUNET_JSON_spec_object_const ("credit_facade_credentials",
+                                     &credit_facade_credentials),
       NULL),
     GNUNET_JSON_spec_end ()
   };
@@ -69,7 +69,6 @@ TMH_cmp_wire_account (
       strcmp (wm->payto_uri,
               uri))
   {
-    GNUNET_JSON_parse_free (ispec);
     return GNUNET_SYSERR;
   }
   if ( (NULL == credit_facade_url) !=
@@ -77,24 +76,20 @@ TMH_cmp_wire_account (
        (NULL == credit_facade_credentials) !=
        (NULL == wm->credit_facade_credentials) )
   {
-    GNUNET_JSON_parse_free (ispec);
     return GNUNET_NO;
   }
   if ( (NULL != credit_facade_url) &&
        (0 != strcmp (credit_facade_url,
                      wm->credit_facade_url)) )
   {
-    GNUNET_JSON_parse_free (ispec);
     return GNUNET_NO;
   }
   if ( (NULL != credit_facade_credentials) &&
        (0 != json_equal (credit_facade_credentials,
                          wm->credit_facade_credentials)) )
   {
-    GNUNET_JSON_parse_free (ispec);
     return GNUNET_NO;
   }
-  GNUNET_JSON_parse_free (ispec);
   return GNUNET_YES;
 }
 
@@ -115,7 +110,7 @@ TMH_accounts_array_valid (const json_t *accounts)
     json_t *payto_uri = json_array_get (accounts,
                                         i);
     const char *credit_facade_url = NULL;
-    json_t *credit_facade_credentials = NULL;
+    const json_t *credit_facade_credentials = NULL;
     const char *uri;
     struct GNUNET_JSON_Specification ispec[] = {
       GNUNET_JSON_spec_string ("payto_uri",
@@ -125,8 +120,8 @@ TMH_accounts_array_valid (const json_t *accounts)
                                  &credit_facade_url),
         NULL),
       GNUNET_JSON_spec_mark_optional (
-        GNUNET_JSON_spec_json ("credit_facade_credentials",
-                               &credit_facade_credentials),
+        GNUNET_JSON_spec_object_const ("credit_facade_credentials",
+                                       &credit_facade_credentials),
         NULL),
       GNUNET_JSON_spec_end ()
     };
@@ -158,7 +153,6 @@ TMH_accounts_array_valid (const json_t *accounts)
                                           "payto_uri"))))
       {
         GNUNET_break_op (0);
-        GNUNET_JSON_parse_free (ispec);
         return false;
       }
     }
@@ -173,7 +167,6 @@ TMH_accounts_array_valid (const json_t *accounts)
                     uri,
                     err);
         GNUNET_free (err);
-        GNUNET_JSON_parse_free (ispec);
         return false;
       }
     }
@@ -198,13 +191,11 @@ TMH_accounts_array_valid (const json_t *accounts)
         GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
                     "Invalid credit facade URL or credentials `%s'\n",
                     credit_facade_url);
-        GNUNET_JSON_parse_free (ispec);
         return false;
       }
       TALER_MERCHANT_BANK_auth_free (&auth);
     }
-    GNUNET_JSON_parse_free (ispec);
-  }
+  } /* end for all accounts */
   return true;
 }
 
@@ -221,7 +212,7 @@ TMH_location_object_valid (const json_t *location)
   const char *street = NULL;
   const char *building = NULL;
   const char *building_no = NULL;
-  json_t *lines = NULL;
+  const json_t *lines = NULL;
   struct GNUNET_JSON_Specification spec[] = {
     GNUNET_JSON_spec_mark_optional (
       GNUNET_JSON_spec_string ("country",
@@ -260,8 +251,8 @@ TMH_location_object_valid (const json_t *location)
                                &building_no),
       NULL),
     GNUNET_JSON_spec_mark_optional (
-      GNUNET_JSON_spec_json ("address_lines",
-                             &lines),
+      GNUNET_JSON_spec_array_const ("address_lines",
+                                    &lines),
       NULL),
     GNUNET_JSON_spec_end ()
   };
@@ -284,13 +275,6 @@ TMH_location_object_valid (const json_t *location)
     size_t idx;
     json_t *line;
 
-    if (! json_is_array (lines))
-    {
-      GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
-                  "Invalid location for field %s\n",
-                  "lines");
-      return false;
-    }
     json_array_foreach (lines, idx, line)
     {
       if (! json_is_string (line))
@@ -326,7 +310,7 @@ TMH_products_array_valid (const json_t *products)
     const char *unit = NULL;
     struct TALER_Amount price = { .value = 0 };
     const char *image_data_url = NULL;
-    json_t *taxes = NULL;
+    const json_t *taxes = NULL;
     struct GNUNET_TIME_Timestamp delivery_date = { 0 };
     struct GNUNET_JSON_Specification spec[] = {
       GNUNET_JSON_spec_mark_optional (
@@ -353,8 +337,8 @@ TMH_products_array_valid (const json_t *products)
                                  &image_data_url),
         NULL),
       GNUNET_JSON_spec_mark_optional (
-        GNUNET_JSON_spec_json ("taxes",
-                               &taxes),
+        GNUNET_JSON_spec_array_const ("taxes",
+                                      &taxes),
         NULL),
       GNUNET_JSON_spec_mark_optional (
         GNUNET_JSON_spec_timestamp ("delivery_date",
diff --git a/src/backend/taler-merchant-httpd_post-orders-ID-abort.c b/src/backend/taler-merchant-httpd_post-orders-ID-abort.c
index 1853e88a..5361496d 100644
--- a/src/backend/taler-merchant-httpd_post-orders-ID-abort.c
+++ b/src/backend/taler-merchant-httpd_post-orders-ID-abort.c
@@ -856,10 +856,10 @@ parse_abort (struct MHD_Connection *connection,
              struct TMH_HandlerContext *hc,
              struct AbortContext *ac)
 {
-  json_t *coins;
+  const json_t *coins;
   struct GNUNET_JSON_Specification spec[] = {
-    GNUNET_JSON_spec_json ("coins",
-                           &coins),
+    GNUNET_JSON_spec_array_const ("coins",
+                                  &coins),
     GNUNET_JSON_spec_fixed_auto ("h_contract",
                                  &ac->h_contract_terms),
 
@@ -878,7 +878,7 @@ parse_abort (struct MHD_Connection *connection,
   ac->coins_cnt = json_array_size (coins);
   if (0 == ac->coins_cnt)
   {
-    GNUNET_JSON_parse_free (spec);
+    GNUNET_break_op (0);
     return TALER_MHD_reply_with_error (connection,
                                        MHD_HTTP_BAD_REQUEST,
                                        TALER_EC_MERCHANT_POST_ORDERS_ID_ABORT_COINS_ARRAY_EMPTY,
@@ -912,7 +912,6 @@ parse_abort (struct MHD_Connection *connection,
                                        ispec);
       if (GNUNET_YES != res)
       {
-        GNUNET_JSON_parse_free (spec);
         GNUNET_break_op (0);
         return res;
       }
@@ -921,7 +920,6 @@ parse_abort (struct MHD_Connection *connection,
       rd->ac = ac;
     }
   }
-  GNUNET_JSON_parse_free (spec);
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
               "Handling /abort for order `%s' with contract hash `%s'\n",
               ac->hc->infix,
diff --git a/src/backend/taler-merchant-httpd_post-orders-ID-pay.c b/src/backend/taler-merchant-httpd_post-orders-ID-pay.c
index bd68278c..04224ac5 100644
--- a/src/backend/taler-merchant-httpd_post-orders-ID-pay.c
+++ b/src/backend/taler-merchant-httpd_post-orders-ID-pay.c
@@ -2219,10 +2219,10 @@ static enum GNUNET_GenericReturnValue
 parse_pay (struct PayContext *pc)
 {
   const char *session_id = NULL;
-  json_t *coins;
+  const json_t *coins;
   struct GNUNET_JSON_Specification spec[] = {
-    GNUNET_JSON_spec_json ("coins",
-                           &coins),
+    GNUNET_JSON_spec_array_const ("coins",
+                                  &coins),
     GNUNET_JSON_spec_mark_optional (
       GNUNET_JSON_spec_string ("session_id",
                                &session_id),
@@ -2253,25 +2253,10 @@ parse_pay (struct PayContext *pc)
     /* use empty string as default if client didn't specify it */
     pc->session_id = GNUNET_strdup ("");
   }
-
-  if (! json_is_array (coins))
-  {
-    GNUNET_break_op (0);
-    GNUNET_JSON_parse_free (spec);
-    return (MHD_YES ==
-            TALER_MHD_reply_with_error (pc->connection,
-                                        MHD_HTTP_BAD_REQUEST,
-                                        TALER_EC_GENERIC_PARAMETER_MISSING,
-                                        "'coins' must be an array"))
-        ? GNUNET_NO
-        : GNUNET_SYSERR;
-  }
-
   pc->coins_cnt = json_array_size (coins);
   if (pc->coins_cnt > MAX_COIN_ALLOWED_COINS)
   {
     GNUNET_break_op (0);
-    GNUNET_JSON_parse_free (spec);
     return (MHD_YES ==
             TALER_MHD_reply_with_error (
               pc->connection,
@@ -2336,7 +2321,6 @@ parse_pay (struct PayContext *pc)
       if (GNUNET_YES != res)
       {
         GNUNET_break_op (0);
-        GNUNET_JSON_parse_free (spec);
         return res;
       }
 
@@ -2347,7 +2331,6 @@ parse_pay (struct PayContext *pc)
                            &pc->dc[j].cdd.coin_pub))
         {
           GNUNET_break_op (0);
-          GNUNET_JSON_parse_free (spec);
           return (MHD_YES ==
                   TALER_MHD_reply_with_error (pc->connection,
                                               MHD_HTTP_BAD_REQUEST,
@@ -2367,7 +2350,6 @@ parse_pay (struct PayContext *pc)
                       TMH_currency))
       {
         GNUNET_break_op (0);
-        GNUNET_JSON_parse_free (spec);
         return (MHD_YES ==
                 TALER_MHD_reply_with_error (pc->connection,
                                             MHD_HTTP_CONFLICT,
@@ -2382,7 +2364,6 @@ parse_pay (struct PayContext *pc)
       if (dc->no_age_commitment != dc->no_minimum_age_sig)
       {
         GNUNET_break_op (0);
-        GNUNET_JSON_parse_free (spec);
         return (MHD_YES ==
                 TALER_MHD_reply_with_error (
                   pc->connection,
@@ -2419,7 +2400,6 @@ parse_pay (struct PayContext *pc)
       }
     }
   }
-  GNUNET_JSON_parse_free (spec);
   return GNUNET_OK;
 }
 
diff --git a/src/backend/taler-merchant-httpd_post-tips-ID-pickup.c b/src/backend/taler-merchant-httpd_post-tips-ID-pickup.c
index da482cda..7cfc4beb 100644
--- a/src/backend/taler-merchant-httpd_post-tips-ID-pickup.c
+++ b/src/backend/taler-merchant-httpd_post-tips-ID-pickup.c
@@ -655,7 +655,7 @@ TMH_post_tips_ID_pickup (const struct TMH_RequestHandler *rh,
 
   if (NULL == pc)
   {
-    json_t *planchets;
+    const json_t *planchets;
     json_t *planchet;
     size_t index;
 
@@ -678,8 +678,8 @@ TMH_post_tips_ID_pickup (const struct TMH_RequestHandler *rh,
 
     {
       struct GNUNET_JSON_Specification spec[] = {
-        GNUNET_JSON_spec_json ("planchets",
-                               &planchets),
+        GNUNET_JSON_spec_array_const ("planchets",
+                                      &planchets),
         GNUNET_JSON_spec_end ()
       };
       {
@@ -694,16 +694,6 @@ TMH_post_tips_ID_pickup (const struct TMH_RequestHandler *rh,
                  : MHD_NO;
       }
     }
-    if (! json_is_array (planchets))
-    {
-      GNUNET_break_op (0);
-      json_decref (planchets);
-      return TALER_MHD_reply_with_error (connection,
-                                         MHD_HTTP_BAD_REQUEST,
-                                         TALER_EC_GENERIC_PARAMETER_MALFORMED,
-                                         "planchets");
-    }
-
     GNUNET_array_grow (pc->planchets,
                        pc->planchets_length,
                        json_array_size (planchets));
@@ -724,14 +714,12 @@ TMH_post_tips_ID_pickup (const struct TMH_RequestHandler *rh,
                                          spec);
         if (GNUNET_OK != res)
         {
-          json_decref (planchets);
           return (GNUNET_NO == res)
                  ? MHD_YES
                  : MHD_NO;
         }
       }
     }
-    json_decref (planchets);
     {
       struct GNUNET_HashContext *hc;
 
diff --git a/src/backend/taler-merchant-httpd_private-patch-instances-ID.c b/src/backend/taler-merchant-httpd_private-patch-instances-ID.c
index 9241d069..5fa66e1f 100644
--- a/src/backend/taler-merchant-httpd_private-patch-instances-ID.c
+++ b/src/backend/taler-merchant-httpd_private-patch-instances-ID.c
@@ -63,14 +63,14 @@ patch_instances_ID (struct TMH_MerchantInstance *mi,
                     struct TMH_HandlerContext *hc)
 {
   struct TALER_MERCHANTDB_InstanceSettings is;
-  json_t *accounts;
+  const json_t *accounts;
   const char *name;
   const char *uts = "business";
   struct TMH_WireMethod *wm_head = NULL;
   struct TMH_WireMethod *wm_tail = NULL;
   struct GNUNET_JSON_Specification spec[] = {
-    GNUNET_JSON_spec_json ("accounts",
-                           &accounts),
+    GNUNET_JSON_spec_array_const ("accounts",
+                                  &accounts),
     GNUNET_JSON_spec_string ("name",
                              &name),
     GNUNET_JSON_spec_mark_optional (
@@ -387,7 +387,7 @@ patch_instances_ID (struct TMH_MerchantInstance *mi,
 
         {
           const char *credit_facade_url = NULL;
-          json_t *credit_facade_credentials = NULL;
+          const json_t *credit_facade_credentials = NULL;
           const char *uri;
           struct GNUNET_JSON_Specification ispec[] = {
             GNUNET_JSON_spec_string ("payto_uri",
@@ -397,8 +397,8 @@ patch_instances_ID (struct TMH_MerchantInstance *mi,
                                        &credit_facade_url),
               NULL),
             GNUNET_JSON_spec_mark_optional (
-              GNUNET_JSON_spec_json ("credit_facade_credentials",
-                                     &credit_facade_credentials),
+              GNUNET_JSON_spec_object_const ("credit_facade_credentials",
+                                             &credit_facade_credentials),
               NULL),
             GNUNET_JSON_spec_end ()
           };
@@ -421,7 +421,6 @@ patch_instances_ID (struct TMH_MerchantInstance *mi,
           GNUNET_CONTAINER_DLL_insert (wm_head,
                                        wm_tail,
                                        wm);
-          GNUNET_JSON_parse_free (ispec);
         } /* ispec scope */
 
         {
diff --git a/src/backend/taler-merchant-httpd_private-patch-orders-ID-forget.c b/src/backend/taler-merchant-httpd_private-patch-orders-ID-forget.c
index 798d610a..78d2189a 100644
--- a/src/backend/taler-merchant-httpd_private-patch-orders-ID-forget.c
+++ b/src/backend/taler-merchant-httpd_private-patch-orders-ID-forget.c
@@ -93,7 +93,7 @@ TMH_private_patch_orders_ID_forget (const struct TMH_RequestHandler *rh,
 
   for (unsigned int i = 0; i<MAX_RETRIES; i++)
   {
-    json_t *fields;
+    const json_t *fields;
     json_t *contract_terms;
     bool changed = false;
     bool paid = false;
@@ -138,8 +138,8 @@ TMH_private_patch_orders_ID_forget (const struct TMH_RequestHandler *rh,
 
     {
       struct GNUNET_JSON_Specification spec[] = {
-        GNUNET_JSON_spec_json ("fields",
-                               &fields),
+        GNUNET_JSON_spec_array_const ("fields",
+                                      &fields),
         GNUNET_JSON_spec_end ()
       };
       enum GNUNET_GenericReturnValue res;
@@ -156,17 +156,6 @@ TMH_private_patch_orders_ID_forget (const struct TMH_RequestHandler *rh,
                : MHD_NO;
       }
     }
-    if (! (json_is_array (fields)))
-    {
-      TMH_db->rollback (TMH_db->cls);
-      json_decref (contract_terms);
-      json_decref (fields);
-      return TALER_MHD_reply_with_error (connection,
-                                         MHD_HTTP_BAD_REQUEST,
-                                         TALER_EC_GENERIC_PARAMETER_MALFORMED,
-                                         "fields");
-    }
-
     {
       size_t index;
       json_t *value;
@@ -179,7 +168,6 @@ TMH_private_patch_orders_ID_forget (const struct TMH_RequestHandler *rh,
         {
           TMH_db->rollback (TMH_db->cls);
           json_decref (contract_terms);
-          json_decref (fields);
           return TALER_MHD_reply_with_error (connection,
                                              MHD_HTTP_BAD_REQUEST,
                                              TALER_EC_MERCHANT_PRIVATE_PATCH_ORDERS_ID_FORGET_PATH_SYNTAX_INCORRECT,
@@ -194,7 +182,6 @@ TMH_private_patch_orders_ID_forget (const struct TMH_RequestHandler *rh,
           /* We tried to forget a field that isn't forgettable */
           TMH_db->rollback (TMH_db->cls);
           json_decref (contract_terms);
-          json_decref (fields);
           return TALER_MHD_reply_with_error (connection,
                                              MHD_HTTP_CONFLICT,
                                              TALER_EC_MERCHANT_PRIVATE_PATCH_ORDERS_ID_FORGET_PATH_NOT_FORGETTABLE,
@@ -207,7 +194,6 @@ TMH_private_patch_orders_ID_forget (const struct TMH_RequestHandler *rh,
           /* One of the paths was malformed and couldn't be expanded */
           TMH_db->rollback (TMH_db->cls);
           json_decref (contract_terms);
-          json_decref (fields);
           return TALER_MHD_reply_with_error (connection,
                                              MHD_HTTP_BAD_REQUEST,
                                              TALER_EC_MERCHANT_PRIVATE_PATCH_ORDERS_ID_FORGET_PATH_SYNTAX_INCORRECT,
@@ -220,7 +206,6 @@ TMH_private_patch_orders_ID_forget (const struct TMH_RequestHandler *rh,
     {
       TMH_db->rollback (TMH_db->cls);
       json_decref (contract_terms);
-      json_decref (fields);
       return TALER_MHD_reply_static (connection,
                                      MHD_HTTP_NO_CONTENT,
                                      NULL,
@@ -232,7 +217,6 @@ TMH_private_patch_orders_ID_forget (const struct TMH_RequestHandler *rh,
                                         order_id,
                                         contract_terms);
     json_decref (contract_terms);
-    json_decref (fields);
     if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT != qs)
     {
       TMH_db->rollback (TMH_db->cls);
diff --git a/src/backend/taler-merchant-httpd_private-post-account.c b/src/backend/taler-merchant-httpd_private-post-account.c
index 8e93203b..f9be253c 100644
--- a/src/backend/taler-merchant-httpd_private-post-account.c
+++ b/src/backend/taler-merchant-httpd_private-post-account.c
@@ -37,7 +37,7 @@ TMH_private_post_account (const struct TMH_RequestHandler *rh,
 {
   struct TMH_MerchantInstance *mi = hc->instance;
   const char *credit_facade_url = NULL;
-  json_t *credit_facade_credentials = NULL;
+  const json_t *credit_facade_credentials = NULL;
   const char *uri;
   struct GNUNET_JSON_Specification ispec[] = {
     GNUNET_JSON_spec_string ("payto_uri",
@@ -47,8 +47,8 @@ TMH_private_post_account (const struct TMH_RequestHandler *rh,
                                &credit_facade_url),
       NULL),
     GNUNET_JSON_spec_mark_optional (
-      GNUNET_JSON_spec_json ("credit_facade_credentials",
-                             &credit_facade_credentials),
+      GNUNET_JSON_spec_object_const ("credit_facade_credentials",
+                                     &credit_facade_credentials),
       NULL),
     GNUNET_JSON_spec_end ()
   };
diff --git a/src/backend/taler-merchant-httpd_private-post-instances.c b/src/backend/taler-merchant-httpd_private-post-instances.c
index c8f443cd..97b096d6 100644
--- a/src/backend/taler-merchant-httpd_private-post-instances.c
+++ b/src/backend/taler-merchant-httpd_private-post-instances.c
@@ -101,15 +101,15 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
 {
   struct TALER_MERCHANTDB_InstanceSettings is;
   struct TALER_MERCHANTDB_InstanceAuthSettings ias;
-  json_t *accounts;
+  const json_t *accounts;
   const char *auth_token = NULL;
   const char *uts = "business";
   struct TMH_WireMethod *wm_head = NULL;
   struct TMH_WireMethod *wm_tail = NULL;
-  json_t *jauth;
+  const json_t *jauth;
   struct GNUNET_JSON_Specification spec[] = {
-    GNUNET_JSON_spec_json ("accounts",
-                           &accounts),
+    GNUNET_JSON_spec_array_const ("accounts",
+                                  &accounts),
     GNUNET_JSON_spec_string ("id",
                              (const char **) &is.id),
     GNUNET_JSON_spec_string ("name",
@@ -130,8 +130,8 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
       GNUNET_JSON_spec_string ("logo",
                                (const char **) &is.logo),
       NULL),
-    GNUNET_JSON_spec_json ("auth",
-                           &jauth),
+    GNUNET_JSON_spec_object_const ("auth",
+                                   &jauth),
     GNUNET_JSON_spec_json ("address",
                            &is.address),
     GNUNET_JSON_spec_json ("jurisdiction",
@@ -169,7 +169,6 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
                                                 &is.ut))
   {
     GNUNET_break_op (0);
-    GNUNET_JSON_parse_free (spec);
     return TALER_MHD_reply_with_error (connection,
                                        MHD_HTTP_BAD_REQUEST,
                                        TALER_EC_GENERIC_PARAMETER_MALFORMED,
@@ -222,7 +221,6 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
   if (! TMH_location_object_valid (is.address))
   {
     GNUNET_break_op (0);
-    GNUNET_JSON_parse_free (spec);
     return TALER_MHD_reply_with_error (connection,
                                        MHD_HTTP_BAD_REQUEST,
                                        TALER_EC_GENERIC_PARAMETER_MALFORMED,
@@ -232,7 +230,6 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
   if (! TMH_location_object_valid (is.jurisdiction))
   {
     GNUNET_break_op (0);
-    GNUNET_JSON_parse_free (spec);
     return TALER_MHD_reply_with_error (connection,
                                        MHD_HTTP_BAD_REQUEST,
                                        TALER_EC_GENERIC_PARAMETER_MALFORMED,
@@ -243,7 +240,6 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
        (! TMH_image_data_url_valid (is.logo)) )
   {
     GNUNET_break_op (0);
-    GNUNET_JSON_parse_free (spec);
     return TALER_MHD_reply_with_error (connection,
                                        MHD_HTTP_BAD_REQUEST,
                                        TALER_EC_GENERIC_PARAMETER_MALFORMED,
@@ -259,7 +255,6 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
     {
       if (mi->deleted)
       {
-        GNUNET_JSON_parse_free (spec);
         return TALER_MHD_reply_with_error (connection,
                                            MHD_HTTP_CONFLICT,
                                            TALER_EC_MERCHANT_PRIVATE_POST_INSTANCES_PURGE_REQUIRED,
@@ -317,7 +312,6 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
            (accounts_equal (mi,
                             accounts)) )
       {
-        GNUNET_JSON_parse_free (spec);
         return TALER_MHD_reply_static (connection,
                                        MHD_HTTP_NO_CONTENT,
                                        NULL,
@@ -326,7 +320,6 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
       }
       else
       {
-        GNUNET_JSON_parse_free (spec);
         return TALER_MHD_reply_with_error (connection,
                                            MHD_HTTP_CONFLICT,
                                            TALER_EC_MERCHANT_PRIVATE_POST_INSTANCES_ALREADY_EXISTS,
@@ -344,7 +337,7 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
       json_t *account = json_array_get (accounts,
                                         i);
       const char *credit_facade_url = NULL;
-      json_t *credit_facade_credentials = NULL;
+      const json_t *credit_facade_credentials = NULL;
       const char *uri;
       struct TMH_WireMethod *wm;
       struct GNUNET_JSON_Specification ispec[] = {
@@ -355,8 +348,8 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
                                    &credit_facade_url),
           NULL),
         GNUNET_JSON_spec_mark_optional (
-          GNUNET_JSON_spec_json ("credit_facade_credentials",
-                                 &credit_facade_credentials),
+          GNUNET_JSON_spec_object_const ("credit_facade_credentials",
+                                         &credit_facade_credentials),
           NULL),
         GNUNET_JSON_spec_end ()
       };
@@ -376,7 +369,6 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
       GNUNET_CONTAINER_DLL_insert (wm_head,
                                    wm_tail,
                                    wm);
-      GNUNET_JSON_parse_free (ispec);
     }
   }
 
@@ -428,7 +420,6 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
           TMH_db->start (TMH_db->cls,
                          "post /instances"))
       {
-        GNUNET_JSON_parse_free (spec);
         mi->rc = 1;
         TMH_instance_decref (mi);
         return TALER_MHD_reply_with_error (connection,
@@ -452,7 +443,6 @@ TMH_private_post_instances (const struct TMH_RequestHandler *rh,
                                           MHD_HTTP_CONFLICT,
                                           TALER_EC_MERCHANT_PRIVATE_POST_INSTANCES_ALREADY_EXISTS,
                                           is.id);
-        GNUNET_JSON_parse_free (spec);
         mi->rc = 1;
         TMH_instance_decref (mi);
         return ret;
@@ -504,7 +494,6 @@ retry:
     } /* for .. MAX_RETRIES */
     if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT != qs)
     {
-      GNUNET_JSON_parse_free (spec);
       mi->rc = 1;
       TMH_instance_decref (mi);
       return TALER_MHD_reply_with_error (connection,
@@ -517,7 +506,6 @@ retry:
                    TMH_add_instance (mi));
     TMH_reload_instances (mi->settings.id);
   }
-  GNUNET_JSON_parse_free (spec);
   if (0 == strcmp (is.id,
                    "default"))
   {
diff --git a/src/include/taler_merchant_service.h b/src/include/taler_merchant_service.h
index b1b4d003..3d64833f 100644
--- a/src/include/taler_merchant_service.h
+++ b/src/include/taler_merchant_service.h
@@ -413,7 +413,7 @@ struct TALER_MERCHANT_InstanceInformation
    * JSON array of payment targets (strings) supported by this backend
    * instance.
    */
-  json_t *payment_targets;
+  const json_t *payment_targets;
 
   /**
    * User type for the instance.
diff --git a/src/lib/merchant_api_get_instance.c b/src/lib/merchant_api_get_instance.c
index 6224e1b4..cf58f828 100644
--- a/src/lib/merchant_api_get_instance.c
+++ b/src/lib/merchant_api_get_instance.c
@@ -93,13 +93,13 @@ handle_get_instance_finished (void *cls,
   {
   case MHD_HTTP_OK:
     {
-      json_t *accounts;
+      const json_t *accounts;
       const char *uts;
-      json_t *address;
-      json_t *jurisdiction;
+      const json_t *address;
+      const json_t *jurisdiction;
       struct GNUNET_JSON_Specification spec[] = {
-        GNUNET_JSON_spec_json ("accounts",
-                               &accounts),
+        GNUNET_JSON_spec_array_const ("accounts",
+                                      &accounts),
         GNUNET_JSON_spec_string ("name",
                                  &igr.details.ok.details.name),
         GNUNET_JSON_spec_string ("user_type",
@@ -107,10 +107,10 @@ handle_get_instance_finished (void *cls,
         GNUNET_JSON_spec_fixed_auto (
           "merchant_pub",
           &igr.details.ok.details.merchant_pub),
-        GNUNET_JSON_spec_json ("address",
-                               &address),
-        GNUNET_JSON_spec_json ("jurisdiction",
-                               &jurisdiction),
+        GNUNET_JSON_spec_object_const ("address",
+                                       &address),
+        GNUNET_JSON_spec_object_const ("jurisdiction",
+                                       &jurisdiction),
         TALER_JSON_spec_amount_any (
           "default_max_wire_fee",
           &igr.details.ok.details.default_max_wire_fee),
@@ -129,14 +129,13 @@ handle_get_instance_finished (void *cls,
         GNUNET_JSON_spec_end ()
       };
 
-      if ( (GNUNET_OK ==
-            GNUNET_JSON_parse (json,
-                               spec,
-                               NULL, NULL)) &&
-           (json_is_array (accounts)) )
+      if (GNUNET_OK ==
+          GNUNET_JSON_parse (json,
+                             spec,
+                             NULL, NULL))
       {
         unsigned int accounts_length = json_array_size (accounts);
-        struct TALER_MERCHANT_Account aa[accounts_length];
+        struct TALER_MERCHANT_Account aa[GNUNET_NZL (accounts_length)];
         size_t index;
         json_t *value;
         int ret = GNUNET_OK;
@@ -146,7 +145,7 @@ handle_get_instance_finished (void *cls,
                 sizeof (aa));
         json_array_foreach (accounts, index, value)
         {
-          struct GNUNET_JSON_Specification spec[] = {
+          struct GNUNET_JSON_Specification ispec[] = {
             GNUNET_JSON_spec_fixed_auto ("salt",
                                          &aa[index].salt),
             GNUNET_JSON_spec_mark_optional (
@@ -164,7 +163,7 @@ handle_get_instance_finished (void *cls,
 
           if (GNUNET_OK !=
               GNUNET_JSON_parse (value,
-                                 spec,
+                                 ispec,
                                  NULL, NULL))
           {
             GNUNET_break_op (0);
@@ -188,14 +187,12 @@ handle_get_instance_finished (void *cls,
             ret = GNUNET_SYSERR;
             igr.hr.http_status = 0;
             igr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
-            GNUNET_JSON_parse_free (spec);
             break;
           }
           igr.details.ok.accounts_length = accounts_length;
           igr.details.ok.accounts = aa;
           igh->cb (igh->cb_cls,
                    &igr);
-          GNUNET_JSON_parse_free (spec);
           TALER_MERCHANT_instance_get_cancel (igh);
           return;
         }
@@ -203,7 +200,6 @@ handle_get_instance_finished (void *cls,
       GNUNET_break_op (0);
       igr.hr.http_status = 0;
       igr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
-      GNUNET_JSON_parse_free (spec);
       break;
     }
   case MHD_HTTP_UNAUTHORIZED:
diff --git a/src/lib/merchant_api_get_instances.c b/src/lib/merchant_api_get_instances.c
index 5f26eb48..c0553941 100644
--- a/src/lib/merchant_api_get_instances.c
+++ b/src/lib/merchant_api_get_instances.c
@@ -81,7 +81,6 @@ parse_instances (const json_t *json,
   struct TALER_MERCHANT_InstanceInformation iis[GNUNET_NZL (iis_len)];
   size_t index;
   json_t *value;
-  enum GNUNET_GenericReturnValue ret;
   struct TALER_MERCHANT_InstancesGetResponse igr = {
     .hr.http_status = MHD_HTTP_OK,
     .hr.reply = json,
@@ -89,7 +88,6 @@ parse_instances (const json_t *json,
     .details.ok.iis = iis
   };
 
-  ret = GNUNET_OK;
   json_array_foreach (ia, index, value) {
     struct TALER_MERCHANT_InstanceInformation *ii = &iis[index];
     const char *uts;
@@ -102,8 +100,8 @@ parse_instances (const json_t *json,
                                &ii->id),
       GNUNET_JSON_spec_fixed_auto ("merchant_pub",
                                    &ii->merchant_pub),
-      GNUNET_JSON_spec_json ("payment_targets",
-                             &ii->payment_targets),
+      GNUNET_JSON_spec_array_const ("payment_targets",
+                                    &ii->payment_targets),
       GNUNET_JSON_spec_end ()
     };
 
@@ -113,24 +111,14 @@ parse_instances (const json_t *json,
                            NULL, NULL))
     {
       GNUNET_break_op (0);
-      ret = GNUNET_SYSERR;
-      continue;
+      return GNUNET_SYSERR;
     }
     if (GNUNET_OK !=
         TALER_KYCLOGIC_kyc_user_type_from_string (uts,
                                                   &ii->ut))
     {
       GNUNET_break_op (0);
-      ret = GNUNET_SYSERR;
-      GNUNET_JSON_parse_free (spec);
-      break;
-    }
-    if (! json_is_array (ii->payment_targets))
-    {
-      GNUNET_break_op (0);
-      ret = GNUNET_SYSERR;
-      GNUNET_JSON_parse_free (spec);
-      break;
+      return GNUNET_SYSERR;
     }
     for (unsigned int i = 0; i<json_array_size (ii->payment_targets); i++)
     {
@@ -138,27 +126,14 @@ parse_instances (const json_t *json,
                                              i)))
       {
         GNUNET_break_op (0);
-        ret = GNUNET_SYSERR;
-        GNUNET_JSON_parse_free (spec);
-        break;
+        return GNUNET_SYSERR;
       }
     }
-    if (GNUNET_SYSERR == ret)
-    {
-      GNUNET_JSON_parse_free (spec);
-      break;
-    }
-  }
-  if (GNUNET_OK == ret)
-  {
-    igh->cb (igh->cb_cls,
-             &igr);
-    igh->cb = NULL; /* just to be sure */
-  }
-  for (unsigned int i = 0; i<iis_len; i++)
-    if (NULL != iis[i].payment_targets)
-      json_decref (iis[i].payment_targets);
-  return ret;
+  } /* for all instances */
+  igh->cb (igh->cb_cls,
+           &igr);
+  igh->cb = NULL; /* just to be sure */
+  return GNUNET_OK;
 }
 
 
@@ -190,10 +165,10 @@ handle_instances_finished (void *cls,
   {
   case MHD_HTTP_OK:
     {
-      json_t *instances;
+      const json_t *instances;
       struct GNUNET_JSON_Specification spec[] = {
-        GNUNET_JSON_spec_json ("instances",
-                               &instances),
+        GNUNET_JSON_spec_array_const ("instances",
+                                      &instances),
         GNUNET_JSON_spec_end ()
       };
 
@@ -204,26 +179,18 @@ handle_instances_finished (void *cls,
       {
         igr.hr.http_status = 0;
         igr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
+        break;
       }
-      else
+      if (GNUNET_OK ==
+          parse_instances (json,
+                           instances,
+                           igh))
       {
-        if ( (! json_is_array (instances)) ||
-             (GNUNET_OK ==
-              parse_instances (json,
-                               instances,
-                               igh)) )
-        {
-          GNUNET_JSON_parse_free (spec);
-          TALER_MERCHANT_instances_get_cancel (igh);
-          return;
-        }
-        else
-        {
-          igr.hr.http_status = 0;
-          igr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
-        }
+        TALER_MERCHANT_instances_get_cancel (igh);
+        return;
       }
-      GNUNET_JSON_parse_free (spec);
+      igr.hr.http_status = 0;
+      igr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
       break;
     }
   case MHD_HTTP_UNAUTHORIZED:
diff --git a/src/lib/merchant_api_get_kyc.c b/src/lib/merchant_api_get_kyc.c
index 0b62d2cf..c394590a 100644
--- a/src/lib/merchant_api_get_kyc.c
+++ b/src/lib/merchant_api_get_kyc.c
@@ -1,6 +1,6 @@
 /*
   This file is part of TALER
-  Copyright (C) 2021 Taler Systems SA
+  Copyright (C) 2023 Taler Systems SA
 
   TALER is free software; you can redistribute it and/or modify it under the
   terms of the GNU Lesser General Public License as published by the Free Software
@@ -76,8 +76,8 @@ struct TALER_MERCHANT_KycGetHandle
 static enum GNUNET_GenericReturnValue
 parse_kyc (struct TALER_MERCHANT_KycGetHandle *kyc,
            struct TALER_MERCHANT_KycResponse *kr,
-           json_t *pends,
-           json_t *touts)
+           const json_t *pends,
+           const json_t *touts)
 {
   unsigned int num_pends = json_array_size (pends);
   unsigned int num_touts = json_array_size (touts);
@@ -186,13 +186,13 @@ handle_get_kyc_finished (void *cls,
   case MHD_HTTP_BAD_GATEWAY:
   case MHD_HTTP_GATEWAY_TIMEOUT:
     {
-      json_t *pends;
-      json_t *touts;
+      const json_t *pends;
+      const json_t *touts;
       struct GNUNET_JSON_Specification spec[] = {
-        GNUNET_JSON_spec_json ("pending_kycs",
-                               &pends),
-        GNUNET_JSON_spec_json ("timeout_kycs",
-                               &touts),
+        GNUNET_JSON_spec_array_const ("pending_kycs",
+                                      &pends),
+        GNUNET_JSON_spec_array_const ("timeout_kycs",
+                                      &touts),
         GNUNET_JSON_spec_end ()
       };
 
@@ -205,20 +205,17 @@ handle_get_kyc_finished (void *cls,
         kr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
         break;
       }
-      if ( (! json_is_array (pends)) ||
-           (! json_is_array (touts)) ||
-           (GNUNET_OK !=
-            parse_kyc (kyc,
-                       &kr,
-                       pends,
-                       touts)) )
+      if (GNUNET_OK !=
+          parse_kyc (kyc,
+                     &kr,
+                     pends,
+                     touts))
       {
         kr.hr.http_status = 0;
         kr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
         break;
       }
       /* parse_kyc called the continuation already */
-      GNUNET_JSON_parse_free (spec);
       TALER_MERCHANT_kyc_get_cancel (kyc);
       return;
     }
diff --git a/src/lib/merchant_api_get_orders.c b/src/lib/merchant_api_get_orders.c
index 5bad47e0..966ecb15 100644
--- a/src/lib/merchant_api_get_orders.c
+++ b/src/lib/merchant_api_get_orders.c
@@ -148,10 +148,10 @@ handle_get_orders_finished (void *cls,
   {
   case MHD_HTTP_OK:
     {
-      json_t *orders;
+      const json_t *orders;
       struct GNUNET_JSON_Specification spec[] = {
-        GNUNET_JSON_spec_json ("orders",
-                               &orders),
+        GNUNET_JSON_spec_array_const ("orders",
+                                      &orders),
         GNUNET_JSON_spec_end ()
       };
 
@@ -162,23 +162,18 @@ handle_get_orders_finished (void *cls,
       {
         ogr.hr.http_status = 0;
         ogr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
+        break;
       }
-      else
+      if (GNUNET_OK ==
+          parse_orders (orders,
+                        &ogr,
+                        ogh))
       {
-        if ( (! json_is_array (orders)) ||
-             (GNUNET_OK ==
-              parse_orders (orders,
-                            &ogr,
-                            ogh)) )
-        {
-          GNUNET_JSON_parse_free (spec);
-          TALER_MERCHANT_orders_get_cancel (ogh);
-          return;
-        }
-        ogr.hr.http_status = 0;
-        ogr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
+        TALER_MERCHANT_orders_get_cancel (ogh);
+        return;
       }
-      GNUNET_JSON_parse_free (spec);
+      ogr.hr.http_status = 0;
+      ogr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
       break;
     }
   case MHD_HTTP_UNAUTHORIZED:
diff --git a/src/lib/merchant_api_get_products.c b/src/lib/merchant_api_get_products.c
index 98976237..01115094 100644
--- a/src/lib/merchant_api_get_products.c
+++ b/src/lib/merchant_api_get_products.c
@@ -149,10 +149,10 @@ handle_get_products_finished (void *cls,
   {
   case MHD_HTTP_OK:
     {
-      json_t *products;
+      const json_t *products;
       struct GNUNET_JSON_Specification spec[] = {
-        GNUNET_JSON_spec_json ("products",
-                               &products),
+        GNUNET_JSON_spec_array_const ("products",
+                                      &products),
         GNUNET_JSON_spec_end ()
       };
 
@@ -163,26 +163,18 @@ handle_get_products_finished (void *cls,
       {
         gpr.hr.http_status = 0;
         gpr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
+        break;
       }
-      else
+      if (GNUNET_OK ==
+          parse_products (json,
+                          products,
+                          pgh))
       {
-        if ( (! json_is_array (products)) ||
-             (GNUNET_OK ==
-              parse_products (json,
-                              products,
-                              pgh)) )
-        {
-          GNUNET_JSON_parse_free (spec);
-          TALER_MERCHANT_products_get_cancel (pgh);
-          return;
-        }
-        else
-        {
-          gpr.hr.http_status = 0;
-          gpr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
-        }
+        TALER_MERCHANT_products_get_cancel (pgh);
+        return;
       }
-      GNUNET_JSON_parse_free (spec);
+      gpr.hr.http_status = 0;
+      gpr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
       break;
     }
   case MHD_HTTP_UNAUTHORIZED:
diff --git a/src/lib/merchant_api_get_template.c b/src/lib/merchant_api_get_template.c
index 386026cf..3e4a23a8 100644
--- a/src/lib/merchant_api_get_template.c
+++ b/src/lib/merchant_api_get_template.c
@@ -93,7 +93,7 @@ handle_get_template_finished (void *cls,
   case MHD_HTTP_OK:
     {
       uint32_t alg32;
-      json_t *contract;
+      const json_t *contract;
       struct GNUNET_JSON_Specification spec[] = {
         GNUNET_JSON_spec_string ("template_description",
                                  &tgr.details.ok.template_description),
@@ -103,8 +103,8 @@ handle_get_template_finished (void *cls,
           GNUNET_JSON_spec_string ("pos_key",
                                    &tgr.details.ok.pos_key),
           NULL),
-        GNUNET_JSON_spec_json ("template_contract",
-                               &contract),
+        GNUNET_JSON_spec_object_const ("template_contract",
+                                       &contract),
         GNUNET_JSON_spec_end ()
       };
 
@@ -118,13 +118,11 @@ handle_get_template_finished (void *cls,
         tgr.details.ok.template_contract = contract;
         tgh->cb (tgh->cb_cls,
                  &tgr);
-        GNUNET_JSON_parse_free (spec);
         TALER_MERCHANT_template_get_cancel (tgh);
         return;
       }
       tgr.hr.http_status = 0;
       tgr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
-      GNUNET_JSON_parse_free (spec);
       break;
     }
   case MHD_HTTP_UNAUTHORIZED:
diff --git a/src/lib/merchant_api_merchant_get_order.c b/src/lib/merchant_api_merchant_get_order.c
index a0c1995b..a8a50738 100644
--- a/src/lib/merchant_api_merchant_get_order.c
+++ b/src/lib/merchant_api_merchant_get_order.c
@@ -130,9 +130,9 @@ handle_claimed (struct TALER_MERCHANT_OrderMerchantGetHandle *omgh,
                 struct TALER_MERCHANT_OrderStatusResponse *osr)
 {
   struct GNUNET_JSON_Specification spec[] = {
-    GNUNET_JSON_spec_json ("contract_terms",
-                           (json_t **) &osr->details.ok.details.claimed.
-                           contract_terms),
+    GNUNET_JSON_spec_object_const (
+      "contract_terms",
+      &osr->details.ok.details.claimed.contract_terms),
     GNUNET_JSON_spec_end ()
   };
 
@@ -151,7 +151,6 @@ handle_claimed (struct TALER_MERCHANT_OrderMerchantGetHandle *omgh,
   osr->details.ok.status = TALER_MERCHANT_OSC_CLAIMED;
   omgh->cb (omgh->cb_cls,
             osr);
-  GNUNET_JSON_parse_free (spec);
 }
 
 
@@ -169,9 +168,9 @@ handle_paid (struct TALER_MERCHANT_OrderMerchantGetHandle *omgh,
 {
   uint32_t ec32;
   uint32_t hc32;
-  json_t *wire_details;
-  json_t *wire_reports;
-  json_t *refund_details;
+  const json_t *wire_details;
+  const json_t *wire_reports;
+  const json_t *refund_details;
   struct GNUNET_JSON_Specification spec[] = {
     GNUNET_JSON_spec_bool ("refunded",
                            &osr->details.ok.details.paid.refunded),
@@ -187,15 +186,15 @@ handle_paid (struct TALER_MERCHANT_OrderMerchantGetHandle *omgh,
                              &hc32),
     TALER_JSON_spec_amount_any ("refund_amount",
                                 &osr->details.ok.details.paid.refund_amount),
-    GNUNET_JSON_spec_json (
+    GNUNET_JSON_spec_object_const (
       "contract_terms",
-      (json_t **) &osr->details.ok.details.paid.contract_terms),
-    GNUNET_JSON_spec_json ("wire_details",
-                           &wire_details),
-    GNUNET_JSON_spec_json ("wire_reports",
-                           &wire_reports),
-    GNUNET_JSON_spec_json ("refund_details",
-                           &refund_details),
+      &osr->details.ok.details.paid.contract_terms),
+    GNUNET_JSON_spec_array_const ("wire_details",
+                                  &wire_details),
+    GNUNET_JSON_spec_array_const ("wire_reports",
+                                  &wire_reports),
+    GNUNET_JSON_spec_array_const ("refund_details",
+                                  &refund_details),
     GNUNET_JSON_spec_end ()
   };
 
@@ -211,19 +210,6 @@ handle_paid (struct TALER_MERCHANT_OrderMerchantGetHandle *omgh,
               osr);
     return;
   }
-  if (! (json_is_array (wire_details) &&
-         json_is_array (wire_reports) &&
-         json_is_array (refund_details) &&
-         json_is_object (osr->details.ok.details.paid.contract_terms)) )
-  {
-    GNUNET_break_op (0);
-    osr->hr.http_status = 0;
-    osr->hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED;
-    omgh->cb (omgh->cb_cls,
-              osr);
-    GNUNET_JSON_parse_free (spec);
-    return;
-  }
   osr->details.ok.status = TALER_MERCHANT_OSC_PAID;
   osr->details.ok.details.paid.exchange_ec = (enum TALER_ErrorCode) ec32;
   osr->details.ok.details.paid.exchange_hc = (unsigned int) hc32;
@@ -264,7 +250,6 @@ handle_paid (struct TALER_MERCHANT_OrderMerchantGetHandle *omgh,
         osr->hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED;
         omgh->cb (omgh->cb_cls,
                   osr);
-        GNUNET_JSON_parse_free (spec);
         return;
       }
     }
@@ -300,7 +285,6 @@ handle_paid (struct TALER_MERCHANT_OrderMerchantGetHandle *omgh,
         osr->hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED;
         omgh->cb (omgh->cb_cls,
                   osr);
-        GNUNET_JSON_parse_free (spec);
         return;
       }
       wr->code = (enum TALER_ErrorCode) c32;
@@ -333,7 +317,6 @@ handle_paid (struct TALER_MERCHANT_OrderMerchantGetHandle *omgh,
         osr->hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED;
         omgh->cb (omgh->cb_cls,
                   osr);
-        GNUNET_JSON_parse_free (spec);
         return;
       }
     }
@@ -347,7 +330,6 @@ handle_paid (struct TALER_MERCHANT_OrderMerchantGetHandle *omgh,
     omgh->cb (omgh->cb_cls,
               osr);
   }
-  GNUNET_JSON_parse_free (spec);
 }
 
 
diff --git a/src/lib/merchant_api_post_order_abort.c b/src/lib/merchant_api_post_order_abort.c
index a924119b..3c9665c6 100644
--- a/src/lib/merchant_api_post_order_abort.c
+++ b/src/lib/merchant_api_post_order_abort.c
@@ -111,11 +111,11 @@ check_abort_refund (struct TALER_MERCHANT_OrderAbortHandle *oah,
                     struct TALER_MERCHANT_AbortResponse *ar,
                     const json_t *json)
 {
-  json_t *refunds;
+  const json_t *refunds;
   unsigned int num_refunds;
   struct GNUNET_JSON_Specification spec[] = {
-    GNUNET_JSON_spec_json ("refunds",
-                           &refunds),
+    GNUNET_JSON_spec_array_const ("refunds",
+                                  &refunds),
     GNUNET_JSON_spec_end ()
   };
 
@@ -127,12 +127,6 @@ check_abort_refund (struct TALER_MERCHANT_OrderAbortHandle *oah,
     GNUNET_break_op (0);
     return GNUNET_SYSERR;
   }
-  if (! json_is_array (refunds))
-  {
-    GNUNET_break_op (0);
-    GNUNET_JSON_parse_free (spec);
-    return GNUNET_SYSERR;
-  }
   num_refunds = json_array_size (refunds);
   {
     struct TALER_MERCHANT_AbortedCoin res[GNUNET_NZL (num_refunds)];
@@ -153,7 +147,6 @@ check_abort_refund (struct TALER_MERCHANT_OrderAbortHandle *oah,
                              NULL, NULL))
       {
         GNUNET_break_op (0);
-        GNUNET_JSON_parse_free (spec);
         return GNUNET_SYSERR;
       }
       if (MHD_HTTP_OK == exchange_status)
@@ -172,7 +165,6 @@ check_abort_refund (struct TALER_MERCHANT_OrderAbortHandle *oah,
                                NULL, NULL))
         {
           GNUNET_break_op (0);
-          GNUNET_JSON_parse_free (spec);
           return GNUNET_SYSERR;
         }
 
@@ -187,7 +179,6 @@ check_abort_refund (struct TALER_MERCHANT_OrderAbortHandle *oah,
               &res[i].exchange_sig))
         {
           GNUNET_break_op (0);
-          GNUNET_JSON_parse_free (spec);
           return GNUNET_SYSERR;
         }
       }
@@ -199,7 +190,6 @@ check_abort_refund (struct TALER_MERCHANT_OrderAbortHandle *oah,
                    ar);
     oah->abort_cb = NULL;
   }
-  GNUNET_JSON_parse_free (spec);
   return GNUNET_OK;
 }
 
diff --git a/src/lib/merchant_api_post_order_pay.c b/src/lib/merchant_api_post_order_pay.c
index 6cfeb846..4b674337 100644
--- a/src/lib/merchant_api_post_order_pay.c
+++ b/src/lib/merchant_api_post_order_pay.c
@@ -281,11 +281,11 @@ parse_conflict (struct TALER_MERCHANT_OrderPayHandle *oph,
                 struct TALER_MERCHANT_PayResponse *pr,
                 const json_t *json)
 {
-  json_t *ereply;
+  const json_t *ereply;
   const char *exchange_url;
   struct GNUNET_JSON_Specification spec[] = {
-    GNUNET_JSON_spec_json ("exchange_reply",
-                           &ereply),
+    GNUNET_JSON_spec_object_const ("exchange_reply",
+                                   &ereply),
     GNUNET_JSON_spec_string ("exchange_url",
                              &exchange_url),
     GNUNET_JSON_spec_end ()
@@ -339,10 +339,8 @@ parse_conflict (struct TALER_MERCHANT_OrderPayHandle *oph,
                          NULL, NULL))
   {
     GNUNET_break_op (0);
-    GNUNET_JSON_parse_free (spec);
     return GNUNET_SYSERR;
   }
-  GNUNET_JSON_parse_free (spec);
 
   for (unsigned int i = 0; i<oph->num_coins; i++)
   {