/history API semantics extended.

That API has now a new 'ordering' flag that lets the
client choose what ordering the results should have:
ascending or descending.

In particular, this change adapted the fakebank and
tests logic to such introduction.

src/bank-lib/bank_api_history.c

@@ -256,6 +256,7 @@ handle_history_finished (void *cls,
  * @param auth authentication data to use
  * @param account_number which account number should we query
  * @param direction what kinds of wire transfers should be returned
+ * @param ascending if GNUNET_YES, history elements will be returned in chronological order.
  * @param start_row from which row on do we want to get results, use UINT64_MAX for the latest; exclusive
  * @param num_results how many results do we want; negative numbers to go into the past,
  *                    positive numbers to go into the future starting at @a start_row;
@@ -272,6 +273,7 @@ TALER_BANK_history (struct GNUNET_CURL_Context *ctx,
                     const struct TALER_BANK_AuthenticationData *auth,
                     uint64_t account_number,
                     enum TALER_BANK_Direction direction,
+                    unsigned int ascending,
                     uint64_t start_row,
                     int64_t num_results,
                     TALER_BANK_HistoryResultCallback hres_cb,
@@ -310,25 +312,28 @@ TALER_BANK_history (struct GNUNET_CURL_Context *ctx,
     can = "show";
   else
     can = "omit";
+
   if (UINT64_MAX == start_row)
   {
     GNUNET_asprintf (&url,
-                     "/history?auth=basic&account_number=%llu&delta=%lld&direction=%s&cancelled=%s",
+                     "/history?auth=basic&account_number=%llu&delta=%lld&direction=%s&cancelled=%s&ordering=%s",
                      (unsigned long long) account_number,
                      (long long) num_results,
                      dir,
-                     can);
+                     can,
+                     (GNUNET_YES == ascending) ? "ascending" : "descending");
 
   }
   else
   {
     GNUNET_asprintf (&url,
-                     "/history?auth=basic&account_number=%llu&delta=%lld&start=%llu&direction=%s&cancelled=%s",
+                     "/history?auth=basic&account_number=%llu&delta=%lld&start=%llu&direction=%s&cancelled=%s&ordering=%s",
                      (unsigned long long) account_number,
                      (long long) num_results,
                      (unsigned long long) start_row,
                      dir,
-                     can);
+                     can,
+                     (GNUNET_YES == ascending) ? "ascending" : "descending");
   }
 
   hh = GNUNET_new (struct TALER_BANK_HistoryHandle);

src/bank-lib/fakebank.c

@@ -95,6 +95,30 @@ struct Transaction
 };
 
 
+/**
+ * Needed to implement ascending/descending ordering
+ * of /history results.
+ */
+struct HistoryElement
+{
+
+  /**
+   * History JSON element.
+   */
+  json_t *element;
+
+  /**
+   * Previous element.
+   */
+  struct HistoryElement *prev;
+
+  /**
+   * Next element.
+   */
+  struct HistoryElement *next;
+};
+
+
 /**
  * Handle for the fake bank.
  */
@@ -660,6 +684,7 @@ handle_history (struct TALER_FAKEBANK_Handle *h,
   const char *dir;
   const char *acc;
   const char *cancelled;
+  const char *ordering;
   unsigned long long account_number;
   unsigned long long start_number;
   long long count;
@@ -668,6 +693,10 @@ handle_history (struct TALER_FAKEBANK_Handle *h,
   json_t *history;
   json_t *jresponse;
   int ret;
+  int ascending;
+  struct HistoryElement *history_results_head = NULL;
+  struct HistoryElement *history_results_tail = NULL;
+  struct HistoryElement *history_element = NULL;
 
   auth = MHD_lookup_connection_value (connection,
                                       MHD_GET_ARGUMENT_KIND,
@@ -684,6 +713,9 @@ handle_history (struct TALER_FAKEBANK_Handle *h,
   start = MHD_lookup_connection_value (connection,
                                        MHD_GET_ARGUMENT_KIND,
                                        "start");
+  ordering = MHD_lookup_connection_value (connection,
+                                          MHD_GET_ARGUMENT_KIND,
+                                          "ordering");
   acc = MHD_lookup_connection_value (connection,
                                      MHD_GET_ARGUMENT_KIND,
                                      "account_number");
@@ -727,11 +759,11 @@ handle_history (struct TALER_FAKEBANK_Handle *h,
     return MHD_NO;
   }
   GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-              "Client asked for up to %lld results of type %s for account %llu starting at %s\n",
+              "Client asked for up to %lld results of type %s for account %llu starting at %llu\n",
               count,
               dir,
               (unsigned long long) account_number,
-              start);
+              start_number);
   if (0 == strcasecmp (dir,
                        "CREDIT"))
   {
@@ -767,12 +799,7 @@ handle_history (struct TALER_FAKEBANK_Handle *h,
     return MHD_NO;
   }
   if (NULL == start)
-  {
+    pos = h->transactions_tail;
-    if (count > 0)
-      pos = h->transactions_head;
-    else
-      pos = h->transactions_tail;
-  }
   else if (NULL != h->transactions_head)
   {
     for (pos = h->transactions_head;
@@ -800,6 +827,13 @@ handle_history (struct TALER_FAKEBANK_Handle *h,
   }
 
   history = json_array ();
+  if ((NULL != ordering)
+      && 0 == strcmp ("ascending",
+                      ordering))
+    ascending = GNUNET_YES;
+  else
+    ascending = GNUNET_NO;
+
   while ( (NULL != pos) &&
           (0 != count) )
   {
@@ -846,8 +880,19 @@ handle_history (struct TALER_FAKEBANK_Handle *h,
                        "wt_subject", subject);
     GNUNET_assert (NULL != trans);
     GNUNET_free (subject);
-    GNUNET_assert (0 == json_array_append_new (history,
+    
-                                               trans));
+    history_element = GNUNET_new (struct HistoryElement);
+    history_element->element = trans;
+
+    if (((0 < count) && (GNUNET_YES == ascending))
+      || ((0 > count) && (GNUNET_NO == ascending)))
+    GNUNET_CONTAINER_DLL_insert_tail (history_results_head,
+                                      history_results_tail,
+                                      history_element);
+    else
+      GNUNET_CONTAINER_DLL_insert (history_results_head,
+                                   history_results_tail,
+                                   history_element);
     if (count > 0)
     {
       pos = pos->next;
@@ -859,6 +904,19 @@ handle_history (struct TALER_FAKEBANK_Handle *h,
       count++;
     }
   }
+
+  if (NULL != history_results_head)
+    history_element = history_results_head;
+  while (NULL != history_element)
+  {
+    json_array_append_new (history,
+                           history_element->element);
+    history_element = history_element->next;
+    if (NULL != history_element)
+      GNUNET_free_non_null (history_element->prev);
+  }
+  GNUNET_free_non_null (history_results_tail);
+
   if (0 == json_array_size (history))
   {
     struct MHD_Response *resp;

src/bank-lib/test_bank_api_new.c

@@ -78,6 +78,7 @@ run (void *cls,
                                     bank_url,
                                     EXCHANGE_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_BOTH,
+                                    GNUNET_NO,
                                     NULL,
                                     5),
 
@@ -110,6 +111,7 @@ run (void *cls,
                                     bank_url,
                                     EXCHANGE_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_CREDIT,
+                                    GNUNET_NO,
                                     NULL,
                                     -5),
 
@@ -117,6 +119,7 @@ run (void *cls,
                                     bank_url,
                                     EXCHANGE_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_DEBIT,
+                                    GNUNET_NO,
                                     NULL,
                                     5),
 
@@ -124,6 +127,7 @@ run (void *cls,
                                     bank_url,
                                     EXCHANGE_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_DEBIT,
+                                    GNUNET_NO,
                                     NULL,
                                     -5),
 
@@ -131,6 +135,7 @@ run (void *cls,
                                     bank_url,
                                     EXCHANGE_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_DEBIT,
+                                    GNUNET_NO,
                                     "deposit-1",
                                     5),
 

src/bank-lib/test_bank_api_twisted.c

@@ -88,6 +88,7 @@ run (void *cls,
                                     twister_url,
                                     EXCHANGE_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_BOTH,
+                                    GNUNET_NO,
                                     NULL,
                                     5),
     /**

src/bank-lib/test_bank_api_with_fakebank.c

@@ -88,13 +88,14 @@ run (void *cls)
       .details.history.account_number = 2,
       .details.history.direction = TALER_BANK_DIRECTION_BOTH,
       .details.history.start_row_ref = NULL,
-      .details.history.num_results = 5 },
+      .details.history.num_results = -5 },
     { .oc = TBI_OC_HISTORY,
       .label = "history-2bi",
       .details.history.account_number = 2,
       .details.history.direction = TALER_BANK_DIRECTION_BOTH,
       .details.history.start_row_ref = "debit-1",
-      .details.history.num_results = 5 },
+      .details.history.num_results = 5,
+      .details.history.ascending = GNUNET_YES},
     /* check transfers arrived at fakebank */
     { .oc = TBI_OC_EXPECT_TRANSFER,
       .label = "expect-2d",
@@ -129,13 +130,13 @@ run (void *cls)
          in the history. So to see the rejected transfer, we need to start
          looking after "credit-2" */
       .details.history.start_row_ref = NULL,
-      .details.history.num_results = 5 },
+      .details.history.num_results = -5 },
     { .oc = TBI_OC_HISTORY,
       .label = "history-r1c",
       .details.history.account_number = 1,
       .details.history.direction = TALER_BANK_DIRECTION_BOTH | TALER_BANK_DIRECTION_CANCEL,
       .details.history.start_row_ref = NULL,
-      .details.history.num_results = 5 },
+      .details.history.num_results = -5 },
     { .oc = TBI_OC_EXPECT_TRANSFER,
       .label = "expect-credit-reject-1",
       .details.expect_transfer.cmd_ref = "credit-for-reject-1" },

src/bank-lib/test_bank_api_with_fakebank_new.c

@@ -73,6 +73,7 @@ run (void *cls,
                                     fakebank_url,
                                     BANK_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_BOTH,
+                                    GNUNET_NO,
                                     NULL,
                                     1),
 
@@ -94,6 +95,7 @@ run (void *cls,
                                     fakebank_url,
                                     BANK_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_CREDIT,
+                                    GNUNET_NO,
                                     NULL,
                                     5),
 
@@ -101,6 +103,7 @@ run (void *cls,
                                     fakebank_url,
                                     BANK_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_DEBIT,
+                                    GNUNET_NO,
                                     NULL,
                                     5),
 
@@ -130,13 +133,15 @@ run (void *cls,
                                     fakebank_url,
                                     EXCHANGE_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_BOTH,
+                                    GNUNET_NO,
                                     NULL,
-                                    5),
+                                    -5),
 
     TALER_TESTING_cmd_bank_history ("history-2bi",
                                     fakebank_url,
                                     EXCHANGE_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_BOTH,
+                                    GNUNET_YES,
                                     "debit-1",
                                     5),
 
@@ -170,16 +175,18 @@ run (void *cls,
                                     fakebank_url,
                                     BANK_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_BOTH,
+                                    GNUNET_NO,
                                     NULL,
-                                    5),
+                                    -5),
 
     TALER_TESTING_cmd_bank_history ("history-r1c",
                                     fakebank_url,
                                     BANK_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_BOTH |
                                     TALER_BANK_DIRECTION_CANCEL,
+                                    GNUNET_NO,
                                     NULL,
-                                    5),
+                                    -5),
 
     TALER_TESTING_cmd_check_bank_transfer_with_ref
       ("expect-credit-reject-1",

src/bank-lib/test_bank_api_with_fakebank_twisted.c

@@ -80,6 +80,7 @@ run (void *cls,
                                     fakebank_url,
                                     EXCHANGE_ACCOUNT_NUMBER,
                                     TALER_BANK_DIRECTION_BOTH,
+                                    GNUNET_NO,
                                     NULL,
                                     5),
     /**

src/bank-lib/test_bank_interpreter.c

@@ -794,6 +794,7 @@ interpreter_run (void *cls)
                             &auth,
                             cmd->details.history.account_number,
                             cmd->details.history.direction,
+                            cmd->details.history.ascending,
                             rowid,
                             cmd->details.history.num_results,
                             &history_cb,

src/bank-lib/test_bank_interpreter.h

@@ -174,6 +174,12 @@ struct TBI_Command
        */
       int failed;
 
+      /**
+       * if true, the history elements will be asked in
+       * chronological order.
+       */
+      unsigned int ascending;
+
     } history;
 
     /**

src/bank-lib/testing_api_cmd_history.c

@@ -84,6 +84,12 @@ struct HistoryState
    * unexpected. 
    */
   int failed;
+
+  /**
+   * If GNUNET_YES, this parameter will ask for results in
+   * chronological order.
+   */
+  unsigned int ascending;
 };
 
 /**
@@ -726,6 +732,7 @@ history_run (void *cls,
                                auth,
                                hs->account_no,
                                hs->direction,
+                               hs->ascending,
                                row_id,
                                hs->num_results,
                                &history_cb,
@@ -765,8 +772,9 @@ history_cleanup
  * @param bank_url base URL of the bank offering the "history"
  *        operation.
  * @param account_no bank account number to ask the history for.
- * @param direction which direction this operation is interested
+ * @param direction which direction this operation is interested.
- *        in.
+ * @param ascending if GNUNET_YES, the bank will return the rows
+ *        in ascending (= chronological) order.
  * @param start_row_reference reference to a command that can
  *        offer a row identifier, to be used as the starting row
  *        to accept in the result.
@@ -780,6 +788,7 @@ TALER_TESTING_cmd_bank_history
    const char *bank_url,
    uint64_t account_no,
    enum TALER_BANK_Direction direction,
+   unsigned int ascending,
    const char *start_row_reference,
    long long num_results)
 {
@@ -792,6 +801,7 @@ TALER_TESTING_cmd_bank_history
   hs->direction = direction;
   hs->start_row_reference = start_row_reference;
   hs->num_results = num_results;
+  hs->ascending = ascending;
 
   cmd.label = label;
   cmd.cls = hs;

src/include/taler_bank_service.h

@@ -257,6 +257,7 @@ typedef void
  * @param auth authentication data to use
  * @param account_number which account number should we query
  * @param direction what kinds of wire transfers should be returned
+ * @param ascending if GNUNET_YES, history elements will be returned in chronological order.
  * @param start_row from which row on do we want to get results, use UINT64_MAX for the latest; exclusive
  * @param num_results how many results do we want; negative numbers to go into the past,
  *                    positive numbers to go into the future starting at @a start_row;
@@ -273,6 +274,7 @@ TALER_BANK_history (struct GNUNET_CURL_Context *ctx,
                     const struct TALER_BANK_AuthenticationData *auth,
                     uint64_t account_number,
                     enum TALER_BANK_Direction direction,
+                    unsigned int ascending,
                     uint64_t start_row,
                     int64_t num_results,
                     TALER_BANK_HistoryResultCallback hres_cb,

src/include/taler_testing_bank_lib.h

@@ -90,7 +90,8 @@ TALER_TESTING_prepare_bank (const char *config_filename);
  *        operation.
  * @param account_no bank account number to ask the history for.
  * @param direction which direction this operation is interested
- *        in.
+ * @param ascending if GNUNET_YES, it ask the bank to return results
+ *        in chronological order.
  * @param start_row_reference reference to a command that can
  *        offer a row identifier, to be used as the starting row
  *        to accept in the result.
@@ -104,6 +105,7 @@ TALER_TESTING_cmd_bank_history
    const char *bank_url,
    uint64_t account_no,
    enum TALER_BANK_Direction direction,
+   unsigned int ascending,
    const char *start_row_reference,
    long long num_results);
 

src/wire-plugins/plugin_wire_taler-bank.c

@@ -1093,6 +1093,8 @@ taler_bank_get_history (void *cls,
                                 &whh->auth,
                                 (uint64_t) account.no,
                                 direction,
+                                /* Defaults to descending ordering always. */
+                                GNUNET_NO,
                                 start_row,
                                 num_results,
                                 &bhist_cb,