adding support for transaction history to wire plugin API (#4959)

5 files changed, 372 insertions, 31 deletions

diff --git a/src/bank-lib/Makefile.am b/src/bank-lib/Makefile.am
index feb7e50f9..48c7e9cb0 100644
--- a/src/bank-lib/Makefile.am
+++ b/src/bank-lib/Makefile.am
@@ -16,7 +16,8 @@ libtalerbank_la_LDFLAGS = \
 
 libtalerbank_la_SOURCES = \
   bank_api_admin.c \
-  bank_api_common.c bank_api_common.h
+  bank_api_common.c bank_api_common.h \
+  bank_api_history.c
 
 libtalerbank_la_LIBADD = \
   $(top_builddir)/src/json/libtalerjson.la \
diff --git a/src/bank-lib/bank_api_admin.c b/src/bank-lib/bank_api_admin.c
index 213cd08b3..375d2ab55 100644
--- a/src/bank-lib/bank_api_admin.c
+++ b/src/bank-lib/bank_api_admin.c
@@ -64,34 +64,6 @@ struct TALER_BANK_AdminAddIncomingHandle
 };
 
 
-
-/**
- * Obtain the URL to use for an API request.
- *
- * @param u base URL of the bank
- * @param path Taler API path (i.e. "/reserve/withdraw")
- * @return the full URI to use with cURL
- */
-static char *
-path_to_url (const char *u,
-             const char *path)
-{
-  char *url;
-
-  if ( ('/' == path[0]) &&
-       (0 < strlen (u)) &&
-       ('/' == u[strlen (u) - 1]) )
-    path++; /* avoid generating URL with "//" from concat */
-  GNUNET_asprintf (&url,
-                   "%s%s",
-                   u,
-                   path);
-  return url;
-}
-
-
-
-
 /**
  * Function called when we're done processing the
  * HTTP /admin/add/incoming request.
@@ -195,8 +167,8 @@ TALER_BANK_admin_add_incoming (struct GNUNET_CURL_Context *ctx,
   aai = GNUNET_new (struct TALER_BANK_AdminAddIncomingHandle);
   aai->cb = res_cb;
   aai->cb_cls = res_cb_cls;
-  aai->request_url = path_to_url (bank_base_url,
-                                  "/admin/add/incoming");
+  aai->request_url = TALER_BANK_path_to_url_ (bank_base_url,
+                                              "/admin/add/incoming");
   aai->authh = TALER_BANK_make_auth_header_ (auth);
   eh = curl_easy_init ();
   GNUNET_assert (NULL != (aai->json_enc =
diff --git a/src/bank-lib/bank_api_common.c b/src/bank-lib/bank_api_common.c
index 0476379d8..e68ba41b5 100644
--- a/src/bank-lib/bank_api_common.c
+++ b/src/bank-lib/bank_api_common.c
@@ -85,4 +85,32 @@ TALER_BANK_make_auth_header_ (const struct TALER_BANK_AuthenticationData *auth)
   return authh;
 }
 
+
+
+/**
+ * Obtain the URL to use for an API request.
+ *
+ * @param u base URL of the bank
+ * @param path Taler API path (i.e. "/history")
+ * @return the full URI to use with cURL
+ */
+char *
+TALER_BANK_path_to_url_ (const char *u,
+                         const char *path)
+{
+  char *url;
+
+  if ( ('/' == path[0]) &&
+       (0 < strlen (u)) &&
+       ('/' == u[strlen (u) - 1]) )
+    path++; /* avoid generating URL with "//" from concat */
+  GNUNET_asprintf (&url,
+                   "%s%s",
+                   u,
+                   path);
+  return url;
+}
+
+
+
 /* end of bank_api_common.c */
diff --git a/src/bank-lib/bank_api_common.h b/src/bank-lib/bank_api_common.h
index a979ee3ac..9d7a7800c 100644
--- a/src/bank-lib/bank_api_common.h
+++ b/src/bank-lib/bank_api_common.h
@@ -39,4 +39,16 @@ struct curl_slist *
 TALER_BANK_make_auth_header_ (const struct TALER_BANK_AuthenticationData *auth);
 
 
+/**
+ * Obtain the URL to use for an API request.
+ *
+ * @param u base URL of the bank
+ * @param path Taler API path (i.e. "/history")
+ * @return the full URI to use with cURL
+ */
+char *
+TALER_BANK_path_to_url_ (const char *u,
+                         const char *path);
+
+
 #endif
diff --git a/src/bank-lib/bank_api_history.c b/src/bank-lib/bank_api_history.c
new file mode 100644
index 000000000..65087e942
--- /dev/null
+++ b/src/bank-lib/bank_api_history.c
@@ -0,0 +1,328 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2017 GNUnet e.V. & Inria
+
+  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_history.c
+ * @brief Implementation of the /history requests of the bank's HTTP API
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include "bank_api_common.h"
+#include <microhttpd.h> /* just for HTTP status codes */
+#include "taler_signatures.h"
+
+
+/**
+ * @brief A /history Handle
+ */
+struct TALER_BANK_HistoryHandle
+{
+
+  /**
+   * The url for this request.
+   */
+  char *request_url;
+
+  /**
+   * The base URL of the bank.
+   */
+  char *bank_base_url;
+
+  /**
+   * Handle for the request.
+   */
+  struct GNUNET_CURL_Job *job;
+
+  /**
+   * HTTP authentication-related headers for the request.
+   */
+  struct curl_slist *authh;
+
+  /**
+   * Function to call with the result.
+   */
+  TALER_BANK_HistoryResultCallback 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 int
+parse_account_history (struct TALER_BANK_HistoryHandle *hh,
+                       const json_t *history)
+{
+  for (unsigned int i=0;i<json_array_size (history);i++)
+  {
+    struct TALER_BANK_TransferDetails td;
+    const char *sign;
+    uint64_t other_account;
+    uint64_t serial_id;
+    enum TALER_BANK_Direction direction;
+    struct GNUNET_JSON_Specification hist_spec[] = {
+      GNUNET_JSON_spec_string ("sign",
+                               &sign),
+      TALER_JSON_spec_amount ("amount",
+                              &td.amount),
+      GNUNET_JSON_spec_absolute_time ("date",
+                                      &td.execution_date),
+      GNUNET_JSON_spec_uint64 ("row_id",
+                               &serial_id),
+      GNUNET_JSON_spec_string ("wire_subject",
+                               &td.wire_transfer_subject),
+      GNUNET_JSON_spec_uint64 ("other_account",
+                               &other_account),
+      GNUNET_JSON_spec_end()
+    };
+    json_t *transaction = json_array_get (history,
+                                          i);
+
+    if (GNUNET_OK !=
+        GNUNET_JSON_parse (transaction,
+                           hist_spec,
+                           NULL, NULL))
+    {
+      GNUNET_break_op (0);
+      return GNUNET_SYSERR;
+    }
+    td.account_details = json_pack ("{s:s, s:s, s:I}",
+                                    "type", "test",
+                                    "bank_uri", hh->bank_base_url,
+                                    "account_number", (json_int_t) other_account);
+    direction = (0 == strcasecmp (sign,
+                                  "+"))
+      ? TALER_BANK_DIRECTION_CREDIT
+      : TALER_BANK_DIRECTION_DEBIT;
+    hh->hcb (hh->hcb_cls,
+             MHD_HTTP_OK,
+             direction,
+             serial_id,
+             &td,
+             transaction);
+    GNUNET_JSON_parse_free (hist_spec);
+    json_decref (td.account_details);
+  }
+  return GNUNET_OK;
+}
+
+
+/**
+ * Function called when we're done processing the
+ * HTTP /admin/add/incoming request.
+ *
+ * @param cls the `struct TALER_BANK_HistoryHandle`
+ * @param response_code HTTP response code, 0 on error
+ * @param json parsed JSON result, NULL on error
+ */
+static void
+handle_history_finished (void *cls,
+                         long response_code,
+                         const json_t *json)
+{
+  struct TALER_BANK_HistoryHandle *hh = cls;
+
+  hh->job = NULL;
+  switch (response_code)
+  {
+  case 0:
+    break;
+  case MHD_HTTP_OK:
+    if (GNUNET_OK !=
+        parse_account_history (hh,
+                               json))
+    {
+      GNUNET_break_op (0);
+      response_code = 0;
+      break;
+    }
+    response_code = MHD_HTTP_NO_CONTENT; /* signal end of list */
+    break;
+  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 */
+    break;
+  case MHD_HTTP_FORBIDDEN:
+    /* Access denied */
+    break;
+  case MHD_HTTP_UNAUTHORIZED:
+    /* Nothing really to verify, bank says one of the signatures is
+       invalid; as we checked them, this should never happen, we
+       should pass the JSON reply to the application */
+    break;
+  case MHD_HTTP_NOT_FOUND:
+    /* Nothing really to verify, this should never
+       happen, we should pass the JSON reply to the application */
+    break;
+  case MHD_HTTP_INTERNAL_SERVER_ERROR:
+    /* Server had an internal issue; we should retry, but this API
+       leaves this to the application */
+    break;
+  default:
+    /* unexpected response code */
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Unexpected response code %u\n",
+                (unsigned int) response_code);
+    GNUNET_break (0);
+    response_code = 0;
+    break;
+  }
+  hh->hcb (hh->hcb_cls,
+           response_code,
+           TALER_BANK_DIRECTION_NONE,
+           0LLU,
+           NULL,
+           json);
+  TALER_BANK_history_cancel (hh);
+}
+
+
+/**
+ * Request the wire transfer history of a bank account.
+ *
+ * @param ctx curl context for the event loop
+ * @param bank_base_url URL of the bank (used to execute this request)
+ * @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 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;
+ *                    must not be zero.
+ * @param hres_cb the callback to call with the transaction history
+ * @param hres_cb_cls closure for the above callback
+ * @return NULL
+ *         if the inputs are invalid (i.e. zero value for @e num_results).
+ *         In this case, the callback is not called.
+ */
+struct TALER_BANK_HistoryHandle *
+TALER_BANK_history (struct GNUNET_CURL_Context *ctx,
+                    const char *bank_base_url,
+                    const struct TALER_BANK_AuthenticationData *auth,
+                    uint64_t account_number,
+                    enum TALER_BANK_Direction direction,
+                    uint64_t start_row,
+                    int64_t num_results,
+                    TALER_BANK_HistoryResultCallback hres_cb,
+                    void *hres_cb_cls)
+{
+  struct TALER_BANK_HistoryHandle *hh;
+  CURL *eh;
+  char *url;
+
+  if (0 == num_results)
+  {
+    GNUNET_break (0);
+    return NULL;
+  }
+  if (TALER_BANK_DIRECTION_NONE == direction)
+  {
+    GNUNET_break (0);
+    return NULL;
+  }
+  if (UINT64_MAX == start_row)
+  {
+    if (TALER_BANK_DIRECTION_BOTH == direction)
+      GNUNET_asprintf (&url,
+                       "/history?account_number=%llu&num_results=%lld",
+                       (unsigned long long) account_number,
+                       (long long) num_results);
+    else
+      GNUNET_asprintf (&url,
+                       "/history?account_number=%llu&num_results=%lld&direction=%s",
+                       (unsigned long long) account_number,
+                       (long long) num_results,
+                       (TALER_BANK_DIRECTION_CREDIT == direction) ? "credit" : "debit");
+
+  }
+  else
+  {
+    if (TALER_BANK_DIRECTION_BOTH == direction)
+      GNUNET_asprintf (&url,
+                       "/history?account_number=%llu&num_results=%lld&start_row=%llu",
+                       (unsigned long long) account_number,
+                       (long long) num_results,
+                       (unsigned long long) start_row);
+    else
+      GNUNET_asprintf (&url,
+                       "/history?account_number=%llu&num_results=%lld&start_row=%llu&direction=%s",
+                       (unsigned long long) account_number,
+                       (long long) num_results,
+                       (unsigned long long) start_row,
+                       (TALER_BANK_DIRECTION_CREDIT == direction) ? "credit" : "debit");
+  }
+
+  hh = GNUNET_new (struct TALER_BANK_HistoryHandle);
+  hh->hcb = hres_cb;
+  hh->hcb_cls = hres_cb_cls;
+  hh->bank_base_url = GNUNET_strdup (bank_base_url);
+  hh->request_url = TALER_BANK_path_to_url_ (bank_base_url,
+                                             url);
+  GNUNET_free (url);
+  hh->authh = TALER_BANK_make_auth_header_ (auth);
+  eh = curl_easy_init ();
+  GNUNET_assert (CURLE_OK ==
+                 curl_easy_setopt (eh,
+                                   CURLOPT_HTTPHEADER,
+                                   hh->authh));
+  GNUNET_assert (CURLE_OK ==
+                 curl_easy_setopt (eh,
+                                   CURLOPT_URL,
+                                   hh->request_url));
+  hh->job = GNUNET_CURL_job_add (ctx,
+                                 eh,
+                                 GNUNET_NO,
+                                 &handle_history_finished,
+                                 hh);
+  return hh;
+}
+
+
+/**
+ * Cancel a history request.  This function cannot be used on a request
+ * handle if a response is already served for it.
+ *
+ * @param hh the history request handle
+ */
+void
+TALER_BANK_history_cancel (struct TALER_BANK_HistoryHandle *hh)
+{
+  if (NULL != hh->job)
+  {
+    GNUNET_CURL_job_cancel (hh->job);
+    hh->job = NULL;
+  }
+  curl_slist_free_all (hh->authh);
+  GNUNET_free (hh->request_url);
+  GNUNET_free (hh->bank_base_url);
+  GNUNET_free (hh);
+}
+
+
+/* end of bank_api_history.c */