aboutsummaryrefslogtreecommitdiff
path: root/src/bank-lib/bank_api_credit.c
blob: 124415b8063e88f49a0e63bbd7613e00cbf28fbf (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
/*
  This file is part of TALER
  Copyright (C) 2017--2023 Taler Systems SA

  TALER is free software; you can redistribute it and/or
  modify it under the terms of the GNU 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 bank-lib/bank_api_credit.c
 * @brief Implementation of the /history/incoming
 *        requests of the bank's HTTP API.
 * @author Christian Grothoff
 * @author Marcello Stanisci
 */
#include "platform.h"
#include "bank_api_common.h"
#include <microhttpd.h> /* just for HTTP status codes */
#include "taler_signatures.h"


/**
 * How much longer than the application-specified timeout
 * do we wait (giving the server a chance to respond)?
 */
#define GRACE_PERIOD_MS 1000


/**
 * @brief A /history/incoming Handle
 */
struct TALER_BANK_CreditHistoryHandle
{

  /**
   * The url for this request.
   */
  char *request_url;

  /**
   * Handle for the request.
   */
  struct GNUNET_CURL_Job *job;

  /**
   * Function to call with the result.
   */
  TALER_BANK_CreditHistoryCallback hcb;

  /**
   * Closure for @a cb.
   */
  void *hcb_cls;
};


/**
 * Parse history given in JSON format and invoke the callback on each item.
 *
 * @param hh handle to the account history request
 * @param history JSON array with the history
 * @return #GNUNET_OK if history was valid and @a rhistory and @a balance
 *         were set,
 *         #GNUNET_SYSERR if there was a protocol violation in @a history
 */
static enum GNUNET_GenericReturnValue
parse_account_history (struct TALER_BANK_CreditHistoryHandle *hh,
                       const json_t *history)
{
  struct TALER_BANK_CreditHistoryResponse chr = {
    .http_status = MHD_HTTP_OK,
    .ec = TALER_EC_NONE,
    .response = history
  };
  const json_t *history_array;
  struct GNUNET_JSON_Specification spec[] = {
    GNUNET_JSON_spec_array_const ("incoming_transactions",
                                  &history_array),
    GNUNET_JSON_spec_string ("credit_account",
                             &chr.details.ok.credit_account_uri),
    GNUNET_JSON_spec_end ()
  };

  if (GNUNET_OK !=
      GNUNET_JSON_parse (history,
                         spec,
                         NULL,
                         NULL))
  {
    GNUNET_break_op (0);
    return GNUNET_SYSERR;
  }
  {
    size_t len = json_array_size (history_array);
    struct TALER_BANK_CreditDetails cd[GNUNET_NZL (len)];

    GNUNET_break_op (0 != len);
    for (size_t i = 0; i<len; i++)
    {
      struct TALER_BANK_CreditDetails *td = &cd[i];
      struct GNUNET_JSON_Specification hist_spec[] = {
        TALER_JSON_spec_amount_any ("amount",
                                    &td->amount),
        GNUNET_JSON_spec_timestamp ("date",
                                    &td->execution_date),
        GNUNET_JSON_spec_uint64 ("row_id",
                                 &td->serial_id),
        GNUNET_JSON_spec_fixed_auto ("reserve_pub",
                                     &td->reserve_pub),
        GNUNET_JSON_spec_string ("debit_account",
                                 &td->debit_account_uri),
        GNUNET_JSON_spec_end ()
      };
      json_t *transaction = json_array_get (history_array,
                                            i);

      if (GNUNET_OK !=
          GNUNET_JSON_parse (transaction,
                             hist_spec,
                             NULL,
                             NULL))
      {
        GNUNET_break_op (0);
        return GNUNET_SYSERR;
      }
    }
    chr.details.ok.details_length = len;
    chr.details.ok.details = cd;
    hh->hcb (hh->hcb_cls,
             &chr);
  }
  return GNUNET_OK;
}


/**
 * Function called when we're done processing the
 * HTTP /history/incoming request.
 *
 * @param cls the `struct TALER_BANK_CreditHistoryHandle`
 * @param response_code HTTP response code, 0 on error
 * @param response parsed JSON result, NULL on error
 */
static void
handle_credit_history_finished (void *cls,
                                long response_code,
                                const void *response)
{
  struct TALER_BANK_CreditHistoryHandle *hh = cls;
  struct TALER_BANK_CreditHistoryResponse chr = {
    .http_status = response_code,
    .response = response
  };

  hh->job = NULL;
  switch (response_code)
  {
  case 0:
    chr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
    break;
  case MHD_HTTP_OK:
    if (GNUNET_OK !=
        parse_account_history (hh,
                               chr.response))
    {
      GNUNET_break_op (0);
      json_dumpf (chr.response,
                  stderr,
                  JSON_INDENT (2));
      chr.http_status = 0;
      chr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
      break;
    }
    TALER_BANK_credit_history_cancel (hh);
    return;
  case MHD_HTTP_NO_CONTENT:
    break;
  case MHD_HTTP_BAD_REQUEST:
    /* This should never happen, either us or the bank is buggy
       (or API version conflict); just pass JSON reply to the application */
    GNUNET_break_op (0);
    chr.ec = TALER_JSON_get_error_code (chr.response);
    break;
  case MHD_HTTP_UNAUTHORIZED:
    /* Nothing really to verify, bank says the HTTP Authentication
       failed. May happen if HTTP authentication is used and the
       user supplied a wrong username/password combination. */
    chr.ec = TALER_JSON_get_error_code (chr.response);
    break;
  case MHD_HTTP_NOT_FOUND:
    /* Nothing really to verify: the bank is either unaware
       of the endpoint (not a bank), or of the account.
       We should pass the JSON (?) reply to the application */
    chr.ec = TALER_JSON_get_error_code (chr.response);
    break;
  case MHD_HTTP_INTERNAL_SERVER_ERROR:
    /* Server had an internal issue; we should retry, but this API
       leaves this to the application */
    chr.ec = TALER_JSON_get_error_code (chr.response);
    break;
  default:
    /* unexpected response code */
    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
                "Unexpected response code %u\n",
                (unsigned int) response_code);
    chr.ec = TALER_JSON_get_error_code (chr.response);
    break;
  }
  hh->hcb (hh->hcb_cls,
           &chr);
  TALER_BANK_credit_history_cancel (hh);
}


struct TALER_BANK_CreditHistoryHandle *
TALER_BANK_credit_history (struct GNUNET_CURL_Context *ctx,
                           const struct TALER_BANK_AuthenticationData *auth,
                           uint64_t start_row,
                           int64_t num_results,
                           struct GNUNET_TIME_Relative timeout,
                           TALER_BANK_CreditHistoryCallback hres_cb,
                           void *hres_cb_cls)
{
  char url[128];
  struct TALER_BANK_CreditHistoryHandle *hh;
  CURL *eh;
  unsigned long long tms;

  if (0 == num_results)
  {
    GNUNET_break (0);
    return NULL;
  }

  tms = (unsigned long long) (timeout.rel_value_us
                              / GNUNET_TIME_UNIT_MILLISECONDS.rel_value_us);
  if ( ( (UINT64_MAX == start_row) &&
         (0 > num_results) ) ||
       ( (0 == start_row) &&
         (0 < num_results) ) )
  {
    if ( (0 < num_results) &&
         (! GNUNET_TIME_relative_is_zero (timeout)) )
      /* 0 == start_row is implied, go with timeout into future */
      GNUNET_snprintf (url,
                       sizeof (url),
                       "history/incoming?delta=%lld&long_poll_ms=%llu",
                       (long long) num_results,
                       tms);
    else
      /* Going back from current transaction or have no timeout;
         hence timeout makes no sense */
      GNUNET_snprintf (url,
                       sizeof (url),
                       "history/incoming?delta=%lld",
                       (long long) num_results);
  }
  else
  {
    if ( (0 < num_results) &&
         (! GNUNET_TIME_relative_is_zero (timeout)) )
      /* going forward from num_result */
      GNUNET_snprintf (url,
                       sizeof (url),
                       "history/incoming?delta=%lld&start=%llu&long_poll_ms=%llu",
                       (long long) num_results,
                       (unsigned long long) start_row,
                       tms);
    else
      /* going backwards or have no timeout;
         hence timeout makes no sense */
      GNUNET_snprintf (url,
                       sizeof (url),
                       "history/incoming?delta=%lld&start=%llu",
                       (long long) num_results,
                       (unsigned long long) start_row);
  }
  hh = GNUNET_new (struct TALER_BANK_CreditHistoryHandle);
  hh->hcb = hres_cb;
  hh->hcb_cls = hres_cb_cls;
  hh->request_url = TALER_url_join (auth->wire_gateway_url,
                                    url,
                                    NULL);
  if (NULL == hh->request_url)
  {
    GNUNET_free (hh);
    GNUNET_break (0);
    return NULL;
  }
  GNUNET_log (GNUNET_ERROR_TYPE_INFO,
              "Requesting credit history at `%s'\n",
              hh->request_url);
  eh = curl_easy_init ();
  if ( (NULL == eh) ||
       (GNUNET_OK !=
        TALER_BANK_setup_auth_ (eh,
                                auth)) ||
       (CURLE_OK !=
        curl_easy_setopt (eh,
                          CURLOPT_URL,
                          hh->request_url)) )
  {
    GNUNET_break (0);
    TALER_BANK_credit_history_cancel (hh);
    if (NULL != eh)
      curl_easy_cleanup (eh);
    return NULL;
  }
  if (0 != tms)
  {
    GNUNET_break (CURLE_OK ==
                  curl_easy_setopt (eh,
                                    CURLOPT_TIMEOUT_MS,
                                    (long) tms + GRACE_PERIOD_MS));
  }
  hh->job = GNUNET_CURL_job_add2 (ctx,
                                  eh,
                                  NULL,
                                  &handle_credit_history_finished,
                                  hh);
  return hh;
}


void
TALER_BANK_credit_history_cancel (struct TALER_BANK_CreditHistoryHandle *hh)
{
  if (NULL != hh->job)
  {
    GNUNET_CURL_job_cancel (hh->job);
    hh->job = NULL;
  }
  GNUNET_free (hh->request_url);
  GNUNET_free (hh);
}


/* end of bank_api_credit.c */