summaryrefslogtreecommitdiff
path: root/src/backend/taler-merchant-httpd_post-orders-ID-refund.c
blob: 8c44568093ff5db6cf5ce21430029e1c5fa24d1d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
/*
  This file is part of TALER
  (C) 2020 Taler Systems SA

  TALER is free software; you can redistribute it and/or modify
  it under the terms of the GNU Affero General Public License as
  published by the Free Software Foundation; either version 3,
  or (at your option) any later version.

  TALER is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public
  License along with TALER; see the file COPYING.  If not,
  see <http://www.gnu.org/licenses/>
*/

/**
 * @file taler-merchant-httpd_post-orders-ID-refund.c
 * @brief handling of POST /orders/$ID/refund requests
 * @author Jonathan Buchanan
 */
#include "platform.h"
#include <taler/taler_signatures.h>
#include <taler/taler_json_lib.h>
#include <taler/taler_exchange_service.h>
#include "taler-merchant-httpd_auditors.h"
#include "taler-merchant-httpd_exchanges.h"
#include "taler-merchant-httpd_post-orders-ID-refund.h"


/**
 * Information we keep for each coin to be refunded.
 */
struct CoinRefund
{

  /**
   * Kept in a DLL.
   */
  struct CoinRefund *next;

  /**
   * Kept in a DLL.
   */
  struct CoinRefund *prev;

  /**
   * Request to connect to the target exchange.
   */
  struct TMH_EXCHANGES_FindOperation *fo;

  /**
   * Handle for the refund operation with the exchange.
   */
  struct TALER_EXCHANGE_RefundHandle *rh;

  /**
   * Request this operation is part of.
   */
  struct PostRefundData *prd;

  /**
   * URL of the exchange for this @e coin_pub.
   */
  char *exchange_url;

  /**
   * Fully reply from the exchange, only possibly set if
   * we got a JSON reply and a non-#MHD_HTTP_OK error code
   */
  json_t *exchange_reply;

  /**
   * When did the merchant grant the refund. To be used to group events
   * in the wallet.
   */
  struct GNUNET_TIME_Absolute execution_time;

  /**
   * Coin to refund.
   */
  struct TALER_CoinSpendPublicKeyP coin_pub;

  /**
   * Refund transaction ID to use.
   */
  uint64_t rtransaction_id;

  /**
   * Unique serial number identifying the refund.
   */
  uint64_t refund_serial;

  /**
   * Amount to refund.
   */
  struct TALER_Amount refund_amount;

  /**
   * Public key of the exchange affirming the refund.
   */
  struct TALER_ExchangePublicKeyP exchange_pub;

  /**
   * Signature of the exchange affirming the refund.
   */
  struct TALER_ExchangeSignatureP exchange_sig;

  /**
   * HTTP status from the exchange, #MHD_HTTP_OK if
   * @a exchange_pub and @a exchange_sig are valid.
   */
  unsigned int exchange_status;

  /**
   * HTTP error code from the exchange.
   */
  enum TALER_ErrorCode exchange_code;

};


/**
 * Context for the operation.
 */
struct PostRefundData
{

  /**
   * Hashed version of contract terms. All zeros if not provided.
   */
  struct GNUNET_HashCode h_contract_terms;

  /**
   * DLL of (suspended) requests.
   */
  struct PostRefundData *next;

  /**
   * DLL of (suspended) requests.
   */
  struct PostRefundData *prev;

  /**
   * Refunds for this order. Head of DLL.
   */
  struct CoinRefund *cr_head;

  /**
   * Refunds for this order. Tail of DLL.
   */
  struct CoinRefund *cr_tail;

  /**
   * Context of the request.
   */
  struct TMH_HandlerContext *hc;

  /**
   * Entry in the #resume_timeout_heap for this check payment, if we are
   * suspended.
   */
  struct TMH_SuspendedConnection sc;

  /**
   * Which merchant instance is this for?
   */
  struct MerchantInstance *mi;

  /**
   * order ID for the payment
   */
  const char *order_id;

  /**
   * Where to get the contract
   */
  const char *contract_url;

  /**
   * fulfillment URL of the contract (valid as long as
   * @e contract_terms is valid).
   */
  const char *fulfillment_url;

  /**
   * session of the client
   */
  const char *session_id;

  /**
   * Contract terms of the payment we are checking. NULL when they
   * are not (yet) known.
   */
  json_t *contract_terms;

  /**
   * Total refunds granted for this payment. Only initialized
   * if @e refunded is set to true.
   */
  struct TALER_Amount refund_amount;

  /**
   * Did we suspend @a connection?
   */
  bool suspended;

  /**
   * Return code: #TALER_EC_NONE if successful.
   */
  enum TALER_ErrorCode ec;

  /**
   * HTTP status to use for the reply, 0 if not yet known.
   */
  unsigned int http_status;

  /**
   * Set to true if we are dealing with an unclaimed order
   * (and thus @e h_contract_terms is not set, and certain
   * DB queries will not work).
   */
  bool unclaimed;

  /**
   * Set to true if this payment has been refunded and
   * @e refund_amount is initialized.
   */
  bool refunded;

  /**
   * Set to true if a refund is still available for the
   * wallet for this payment.
   */
  bool refund_available;

  /**
   * Set to true if the client requested HTML, otherwise
   * we generate JSON.
   */
  bool generate_html;

};


/**
 * Head of DLL of (suspended) requests.
 */
static struct PostRefundData *prd_head;

/**
 * Tail of DLL of (suspended) requests.
 */
static struct PostRefundData *prd_tail;


/**
 * Function called when we are done processing a refund request.
 * Frees memory associated with @a ctx.
 *
 * @param ctx a `struct PostRefundData`
 */
static void
refund_cleanup (void *ctx)
{
  struct PostRefundData *prd = ctx;
  struct CoinRefund *cr;

  while (NULL != (cr = prd->cr_head))
  {
    GNUNET_CONTAINER_DLL_remove (prd->cr_head,
                                 prd->cr_tail,
                                 cr);
    json_decref (cr->exchange_reply);
    GNUNET_free (cr->exchange_url);
    if (NULL != cr->fo)
    {
      TMH_EXCHANGES_find_exchange_cancel (cr->fo);
      cr->fo = NULL;
    }
    if (NULL != cr->rh)
    {
      TALER_EXCHANGE_refund_cancel (cr->rh);
      cr->rh = NULL;
    }
    GNUNET_free (cr);
  }

  json_decref (prd->contract_terms);

  GNUNET_free (prd);
}


/**
 * Force resuming all suspended order lookups, needed during shutdown.
 */
void
TMH_force_wallet_refund_order_resume (void)
{
  struct PostRefundData *prd;

  while (NULL != (prd = prd_head))
  {
    GNUNET_CONTAINER_DLL_remove (prd_head,
                                 prd_tail,
                                 prd);
    GNUNET_assert (prd->suspended);
    prd->suspended = false;
    MHD_resume_connection (prd->sc.con);
  }
}


/**
 * Check if @a prd has exchange requests still pending.
 *
 * @param prd state to check
 * @return true if activities are still pending
 */
static bool
exchange_operations_pending (struct PostRefundData *prd)
{
  for (struct CoinRefund *cr = prd->cr_head;
       NULL != cr;
       cr = cr->next)
  {
    if ( (NULL != cr->fo) ||
         (NULL != cr->rh) )
      return true;
  }
  return false;
}


/**
 * Check if @a prd is ready to be resumed, and if so, do it.
 *
 * @param prd refund request to be possibly ready
 */
static void
check_resume_prd (struct PostRefundData *prd)
{
  if ( (TALER_EC_NONE == prd->ec) &&
       exchange_operations_pending (prd) )
    return;
  GNUNET_CONTAINER_DLL_remove (prd_head,
                               prd_tail,
                               prd);
  GNUNET_assert (prd->suspended);
  prd->suspended = false;
  MHD_resume_connection (prd->sc.con);
  TMH_trigger_daemon ();
}


/**
 * Callbacks of this type are used to serve the result of submitting a
 * refund request to an exchange.
 *
 * @param cls a `struct CoinRefund`
 * @param hr HTTP response data
 * @param exchange_pub exchange key used to sign refund confirmation
 * @param exchange_sig exchange's signature over refund
 */
static void
refund_cb (void *cls,
           const struct TALER_EXCHANGE_HttpResponse *hr,
           const struct TALER_ExchangePublicKeyP *exchange_pub,
           const struct TALER_ExchangeSignatureP *exchange_sig)
{
  struct CoinRefund *cr = cls;

  cr->rh = NULL;
  cr->exchange_status = hr->http_status;
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Exchange refund status for coin %s is %u\n",
              TALER_B2S (&cr->coin_pub),
              hr->http_status);
  if (MHD_HTTP_OK != hr->http_status)
  {
    cr->exchange_code = hr->ec;
    cr->exchange_reply = json_incref ((json_t*) hr->reply);
  }
  else
  {
    enum GNUNET_DB_QueryStatus qs;

    cr->exchange_pub = *exchange_pub;
    cr->exchange_sig = *exchange_sig;
    qs = TMH_db->insert_refund_proof (TMH_db->cls,
                                      cr->refund_serial,
                                      exchange_sig,
                                      exchange_pub);
    if (0 >= qs)
    {
      /* generally, this is relatively harmless for the merchant, but let's at
         least log this. */
      GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
                  "Failed to persist exchange response to /refund in database: %d\n",
                  qs);
    }
  }
  check_resume_prd (cr->prd);
}


/**
 * Function called with the result of a #TMH_EXCHANGES_find_exchange()
 * operation.
 *
 * @param cls a `struct CoinRefund *`
 * @param hr HTTP response details
 * @param eh handle to the exchange context
 * @param payto_uri payto://-URI of the exchange
 * @param wire_fee current applicable wire fee for dealing with @a eh, NULL if not available
 * @param exchange_trusted true if this exchange is trusted by config
 */
static void
exchange_found_cb (void *cls,
                   const struct TALER_EXCHANGE_HttpResponse *hr,
                   struct TALER_EXCHANGE_Handle *eh,
                   const char *payto_uri,
                   const struct TALER_Amount *wire_fee,
                   bool exchange_trusted)
{
  struct CoinRefund *cr = cls;
  struct PostRefundData *prd = cr->prd;

  (void) payto_uri;
  (void) wire_fee;
  (void) exchange_trusted;
  cr->fo = NULL;
  if (NULL == hr)
  {
    prd->http_status = MHD_HTTP_GATEWAY_TIMEOUT;
    prd->ec = TALER_EC_MERCHANT_GENERIC_EXCHANGE_TIMEOUT;
    check_resume_prd (prd);
    return;
  }
  if (NULL == eh)
  {
    prd->http_status = MHD_HTTP_BAD_GATEWAY;
    prd->ec = TALER_EC_MERCHANT_GENERIC_EXCHANGE_CONNECT_FAILURE;
    check_resume_prd (prd);
    return;
  }
  cr->rh = TALER_EXCHANGE_refund (eh,
                                  &cr->refund_amount,
                                  &prd->h_contract_terms,
                                  &cr->coin_pub,
                                  cr->rtransaction_id,
                                  &prd->hc->instance->merchant_priv,
                                  &refund_cb,
                                  cr);
}


/**
 * Function called with information about a refund.
 * It is responsible for summing up the refund amount.
 *
 * @param cls closure
 * @param refund_serial unique serial number of the refund
 * @param timestamp time of the refund (for grouping of refunds in the wallet UI)
 * @param coin_pub public coin from which the refund comes from
 * @param exchange_url URL of the exchange that issued @a coin_pub
 * @param rtransaction_id identificator of the refund
 * @param reason human-readable explanation of the refund
 * @param refund_amount refund amount which is being taken from @a coin_pub
 * @param pending true if the this refund was not yet processed by the wallet/exchange
 */
static void
process_refunds_cb (void *cls,
                    uint64_t refund_serial,
                    struct GNUNET_TIME_Absolute timestamp,
                    const struct TALER_CoinSpendPublicKeyP *coin_pub,
                    const char *exchange_url,
                    uint64_t rtransaction_id,
                    const char *reason,
                    const struct TALER_Amount *refund_amount,
                    bool pending)
{
  struct PostRefundData *prd = cls;
  struct CoinRefund *cr;

  for (cr = prd->cr_head;
       NULL != cr;
       cr = cr->next)
    if (cr->refund_serial == refund_serial)
      return;
  /* already known */

  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
              "Found refund of %s for coin %s with reason `%s' in database\n",
              TALER_amount2s (refund_amount),
              TALER_B2S (coin_pub),
              reason);
  cr = GNUNET_new (struct CoinRefund);
  cr->refund_serial = refund_serial;
  cr->exchange_url = GNUNET_strdup (exchange_url);
  cr->prd = prd;
  cr->coin_pub = *coin_pub;
  cr->rtransaction_id = rtransaction_id;
  cr->refund_amount = *refund_amount;
  cr->execution_time = timestamp;
  GNUNET_CONTAINER_DLL_insert (prd->cr_head,
                               prd->cr_tail,
                               cr);
  if (prd->refunded)
  {
    GNUNET_assert (0 <=
                   TALER_amount_add (&prd->refund_amount,
                                     &prd->refund_amount,
                                     refund_amount));
    return;
  }
  prd->refund_amount = *refund_amount;
  prd->refunded = true;
  prd->refund_available |= pending;
}


/**
 * Obtain refunds for an order.
 *
 * @param rh context of the handler
 * @param connection the MHD connection to handle
 * @param[in,out] hc context with further information about the request
 * @return MHD result code
 */
MHD_RESULT
TMH_post_orders_ID_refund (const struct TMH_RequestHandler *rh,
                           struct MHD_Connection *connection,
                           struct TMH_HandlerContext *hc)
{
  struct PostRefundData *prd = hc->ctx;
  enum GNUNET_DB_QueryStatus qs;

  if (NULL == prd)
  {
    prd = GNUNET_new (struct PostRefundData);
    prd->sc.con = connection;
    prd->hc = hc;
    prd->order_id = hc->infix;
    hc->ctx = prd;
    hc->cc = &refund_cleanup;
    {
      enum GNUNET_GenericReturnValue res;

      struct GNUNET_JSON_Specification spec[] = {
        GNUNET_JSON_spec_fixed_auto ("h_contract", &prd->h_contract_terms),
        GNUNET_JSON_spec_end ()
      };
      res = TALER_MHD_parse_json_data (connection,
                                       hc->request_body,
                                       spec);
      if (GNUNET_OK != res)
        return (GNUNET_NO == res)
               ? MHD_YES
               : MHD_NO;
    }

    TMH_db->preflight (TMH_db->cls);
    {
      json_t *contract_terms;
      uint64_t order_serial;

      qs = TMH_db->lookup_contract_terms (TMH_db->cls,
                                          hc->instance->settings.id,
                                          hc->infix,
                                          &contract_terms,
                                          &order_serial);
      if (0 > qs)
      {
        /* single, read-only SQL statements should never cause
           serialization problems */
        GNUNET_break (GNUNET_DB_STATUS_SOFT_ERROR != qs);
        /* Always report on hard error as well to enable diagnostics */
        GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR == qs);
        return TALER_MHD_reply_with_error (connection,
                                           MHD_HTTP_INTERNAL_SERVER_ERROR,
                                           TALER_EC_GENERIC_DB_FETCH_FAILED,
                                           "contract terms");
      }
      if (GNUNET_DB_STATUS_SUCCESS_NO_RESULTS == qs)
      {
        json_decref (contract_terms);
        return TALER_MHD_reply_with_error (connection,
                                           MHD_HTTP_NOT_FOUND,
                                           TALER_EC_MERCHANT_GENERIC_ORDER_UNKNOWN,
                                           hc->infix);
      }
      {
        struct GNUNET_HashCode h_contract_terms;
        if (GNUNET_OK !=
            TALER_JSON_contract_hash (contract_terms,
                                      &h_contract_terms))
        {
          GNUNET_break (0);
          json_decref (contract_terms);
          return TALER_MHD_reply_with_error (connection,
                                             MHD_HTTP_INTERNAL_SERVER_ERROR,
                                             TALER_EC_GENERIC_FAILED_COMPUTE_JSON_HASH,
                                             NULL);
        }
        json_decref (contract_terms);
        if (0 != GNUNET_memcmp (&h_contract_terms,
                                &prd->h_contract_terms))
        {
          return TALER_MHD_reply_with_error (
            connection,
            MHD_HTTP_FORBIDDEN,
            TALER_EC_MERCHANT_GENERIC_CONTRACT_HASH_DOES_NOT_MATCH_ORDER,
            NULL);
        }
      }
    }
  }

  if (TALER_EC_NONE != prd->ec)
  {
    GNUNET_break (0 != prd->http_status);
    /* kill pending coin refund operations immediately, just to be
       extra sure they don't modify 'prd' after we already created
       a reply (this might not be needed, but feels safer). */
    for (struct CoinRefund *cr = prd->cr_head;
         NULL != cr;
         cr = cr->next)
    {
      if (NULL != cr->fo)
      {
        TMH_EXCHANGES_find_exchange_cancel (cr->fo);
        cr->fo = NULL;
      }
      if (NULL != cr->rh)
      {
        TALER_EXCHANGE_refund_cancel (cr->rh);
        cr->rh = NULL;
      }
    }
    return TALER_MHD_reply_with_error (connection,
                                       prd->http_status,
                                       prd->ec,
                                       NULL);
  }

  {
    GNUNET_assert (GNUNET_OK == TALER_amount_get_zero (TMH_currency,
                                                       &prd->refund_amount));
    qs = TMH_db->lookup_refunds_detailed (TMH_db->cls,
                                          hc->instance->settings.id,
                                          &prd->h_contract_terms,
                                          &process_refunds_cb,
                                          prd);
    if (0 > qs)
    {
      GNUNET_break (0);
      return TALER_MHD_reply_with_error (connection,
                                         MHD_HTTP_INTERNAL_SERVER_ERROR,
                                         TALER_EC_GENERIC_DB_FETCH_FAILED,
                                         "detailed refunds");
    }
  }

  /* Now launch exchange interactions, unless we already have the
     response in the database! */
  for (struct CoinRefund *cr = prd->cr_head;
       NULL != cr;
       cr = cr->next)
  {
    enum GNUNET_DB_QueryStatus qs;

    qs = TMH_db->lookup_refund_proof (TMH_db->cls,
                                      cr->refund_serial,
                                      &cr->exchange_sig,
                                      &cr->exchange_pub);
    switch (qs)
    {
    case GNUNET_DB_STATUS_HARD_ERROR:
    case GNUNET_DB_STATUS_SOFT_ERROR:
      return TALER_MHD_reply_with_error (connection,
                                         MHD_HTTP_INTERNAL_SERVER_ERROR,
                                         TALER_EC_GENERIC_DB_FETCH_FAILED,
                                         "refund proof");
    case GNUNET_DB_STATUS_SUCCESS_NO_RESULTS:
      if (NULL == cr->exchange_reply)
      {
        /* We need to talk to the exchange */
        /* Notify clients waiting for the refund to be obtained. */
        TMH_long_poll_resume (hc->infix,
                              hc->instance,
                              &prd->refund_amount,
                              true);
        cr->fo = TMH_EXCHANGES_find_exchange (cr->exchange_url,
                                              NULL,
                                              GNUNET_NO,
                                              &exchange_found_cb,
                                              cr);
      }
      break;
    case GNUNET_DB_STATUS_SUCCESS_ONE_RESULT:
      /* We got a reply earlier, set status accordingly */
      cr->exchange_status = MHD_HTTP_OK;
      break;
    }
  }

  /* Check if there are still exchange operations pending */
  if (exchange_operations_pending (prd))
  {
    if (! prd->suspended)
    {
      prd->suspended = true;
      MHD_suspend_connection (connection);
      GNUNET_CONTAINER_DLL_insert (prd_head,
                                   prd_tail,
                                   prd);
    }
    return MHD_YES;   /* we're still talking to the exchange */
  }

  {
    json_t *ra;

    ra = json_array ();
    GNUNET_assert (NULL != ra);
    for (struct CoinRefund *cr = prd->cr_head;
         NULL != cr;
         cr = cr->next)
    {
      json_t *refund;

      if (MHD_HTTP_OK != cr->exchange_status)
      {
        if (NULL == cr->exchange_reply)
        {
          refund = json_pack ("{s:s,s:I,s:I,s:o,s:o,s:o}",
                              "type",
                              "failure",
                              "exchange_status",
                              (json_int_t) cr->exchange_status,
                              "rtransaction_id",
                              (json_int_t) cr->rtransaction_id,
                              "coin_pub",
                              GNUNET_JSON_from_data_auto (&cr->coin_pub),
                              "refund_amount",
                              TALER_JSON_from_amount (&cr->refund_amount),
                              "execution_time",
                              GNUNET_JSON_from_time_abs (cr->execution_time));
        }
        else
        {
          refund = json_pack ("{s:s,s:I,s:I,s:O,s:I,s:o,s:o,s:o}",
                              "type",
                              "failure",
                              "exchange_status",
                              (json_int_t) cr->exchange_status,
                              "exchange_code",
                              (json_int_t) cr->exchange_code,
                              "exchange_reply",
                              cr->exchange_reply,
                              "rtransaction_id",
                              (json_int_t) cr->rtransaction_id,
                              "coin_pub",
                              GNUNET_JSON_from_data_auto (&cr->coin_pub),
                              "refund_amount",
                              TALER_JSON_from_amount (&cr->refund_amount),
                              "execution_time",
                              GNUNET_JSON_from_time_abs (cr->execution_time));
        }
      }
      else
      {
        refund = json_pack ("{s:s,s:I,s:o,s:o,s:I,s:o,s:o,s:o}",
                            "type",
                            "success",
                            "exchange_status",
                            (json_int_t) cr->exchange_status,
                            "exchange_sig",
                            GNUNET_JSON_from_data_auto (&cr->exchange_sig),
                            "exchange_pub",
                            GNUNET_JSON_from_data_auto (&cr->exchange_pub),
                            "rtransaction_id",
                            (json_int_t) cr->rtransaction_id,
                            "coin_pub",
                            GNUNET_JSON_from_data_auto (&cr->coin_pub),
                            "refund_amount",
                            TALER_JSON_from_amount (&cr->refund_amount),
                            "execution_time",
                            GNUNET_JSON_from_time_abs (cr->execution_time));
      }
      GNUNET_assert (
        0 ==
        json_array_append_new (ra,
                               refund));
    }

    return TALER_MHD_reply_json_pack (
      connection,
      MHD_HTTP_OK,
      "{s:o, s:o, s:o}",
      "refund_amount",
      TALER_JSON_from_amount (&prd->refund_amount),
      "refunds",
      ra,
      "merchant_pub",
      GNUNET_JSON_from_data_auto (&hc->instance->merchant_pub));
  }

  return MHD_YES;
}


/* end of taler-merchant-httpd_post-orders-ID-refund.c */