add purse delete functions to libtalerexchange

src/include/taler_exchange_service.h

@@ -4983,7 +4983,7 @@ struct TALER_EXCHANGE_PurseDeleteHandle;
  * @param cb_cls closure for @a cb
  * @return the request handle; NULL upon error
  */
-struct TALER_EXCHANGE_PurseCreateDepositHandle *
+struct TALER_EXCHANGE_PurseDeleteHandle *
 TALER_EXCHANGE_purse_delete (
   struct TALER_EXCHANGE_Handle *exchange,
   const struct TALER_PurseContractPrivateKeyP *purse_priv,

src/lib/Makefile.am

@@ -52,6 +52,7 @@ libtalerexchange_la_SOURCES = \
   exchange_api_melt.c \
   exchange_api_purse_create_with_deposit.c \
   exchange_api_purse_create_with_merge.c \
+  exchange_api_purse_delete.c \
   exchange_api_purse_deposit.c \
   exchange_api_purse_merge.c \
   exchange_api_purses_get.c \

src/lib/exchange_api_purse_delete.c

@@ -0,0 +1,239 @@
+/*
+   This file is part of TALER
+   Copyright (C) 2022 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 lib/exchange_api_purse_delete.c
+ * @brief Implementation of the client to delete a purse
+ *        into an account
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include <jansson.h>
+#include <microhttpd.h> /* just for HTTP status codes */
+#include <gnunet/gnunet_util_lib.h>
+#include <gnunet/gnunet_json_lib.h>
+#include <gnunet/gnunet_curl_lib.h>
+#include "taler_json_lib.h"
+#include "taler_exchange_service.h"
+#include "exchange_api_handle.h"
+#include "exchange_api_common.h"
+#include "taler_signatures.h"
+#include "exchange_api_curl_defaults.h"
+
+
+/**
+ * @brief A purse delete with deposit handle
+ */
+struct TALER_EXCHANGE_PurseDeleteHandle
+{
+
+  /**
+   * The connection to exchange this request handle will use
+   */
+  struct TALER_EXCHANGE_Handle *exchange;
+
+  /**
+   * The url for this request.
+   */
+  char *url;
+
+  /**
+   * Handle for the request.
+   */
+  struct GNUNET_CURL_Job *job;
+
+  /**
+   * Function to call with the result.
+   */
+  TALER_EXCHANGE_PurseDeleteCallback cb;
+
+  /**
+   * Closure for @a cb.
+   */
+  void *cb_cls;
+
+  /**
+   * Header with the purse_sig.
+   */
+  struct curl_slist *xhdr;
+};
+
+
+/**
+ * Function called when we're done processing the
+ * HTTP DELETE /purse/$PID request.
+ *
+ * @param cls the `struct TALER_EXCHANGE_PurseDeleteHandle`
+ * @param response_code HTTP response code, 0 on error
+ * @param response parsed JSON result, NULL on error
+ */
+static void
+handle_purse_delete_finished (void *cls,
+                              long response_code,
+                              const void *response)
+{
+  struct TALER_EXCHANGE_PurseDeleteHandle *pdh = cls;
+  const json_t *j = response;
+  struct TALER_EXCHANGE_PurseDeleteResponse dr = {
+    .hr.reply = j,
+    .hr.http_status = (unsigned int) response_code
+  };
+
+  pdh->job = NULL;
+  switch (response_code)
+  {
+  case 0:
+    dr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
+    break;
+  case MHD_HTTP_NO_CONTENT:
+    break;
+  case MHD_HTTP_BAD_REQUEST:
+    /* This should never happen, either us or the exchange is buggy
+       (or API version conflict); just pass JSON reply to the application */
+    dr.hr.ec = TALER_JSON_get_error_code (j);
+    dr.hr.hint = TALER_JSON_get_error_hint (j);
+    break;
+  case MHD_HTTP_FORBIDDEN:
+    dr.hr.ec = TALER_JSON_get_error_code (j);
+    dr.hr.hint = TALER_JSON_get_error_hint (j);
+    /* Nothing really to verify, exchange 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:
+    dr.hr.ec = TALER_JSON_get_error_code (j);
+    dr.hr.hint = TALER_JSON_get_error_hint (j);
+    /* Nothing really to verify, this should never
+       happen, we should pass the JSON reply to the application */
+    break;
+  case MHD_HTTP_CONFLICT:
+    dr.hr.ec = TALER_JSON_get_error_code (j);
+    dr.hr.hint = TALER_JSON_get_error_hint (j);
+    break;
+  case MHD_HTTP_INTERNAL_SERVER_ERROR:
+    dr.hr.ec = TALER_JSON_get_error_code (j);
+    dr.hr.hint = TALER_JSON_get_error_hint (j);
+    /* Server had an internal issue; we should retry, but this API
+       leaves this to the application */
+    break;
+  default:
+    /* unexpected response code */
+    dr.hr.ec = TALER_JSON_get_error_code (j);
+    dr.hr.hint = TALER_JSON_get_error_hint (j);
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Unexpected response code %u/%d for exchange deposit\n",
+                (unsigned int) response_code,
+                dr.hr.ec);
+    GNUNET_break_op (0);
+    break;
+  }
+  pdh->cb (pdh->cb_cls,
+           &dr);
+  TALER_EXCHANGE_purse_delete_cancel (pdh);
+}
+
+
+struct TALER_EXCHANGE_PurseDeleteHandle *
+TALER_EXCHANGE_purse_delete (
+  struct TALER_EXCHANGE_Handle *exchange,
+  const struct TALER_PurseContractPrivateKeyP *purse_priv,
+  TALER_EXCHANGE_PurseDeleteCallback cb,
+  void *cb_cls)
+{
+  struct TALER_EXCHANGE_PurseDeleteHandle *pdh;
+  struct GNUNET_CURL_Context *ctx;
+  CURL *eh;
+  struct TALER_PurseContractPublicKeyP purse_pub;
+  struct TALER_PurseContractSignatureP purse_sig;
+  char arg_str[sizeof (purse_pub) * 2 + 32];
+
+  pdh = GNUNET_new (struct TALER_EXCHANGE_PurseDeleteHandle);
+  pdh->exchange = exchange;
+  pdh->cb = cb;
+  pdh->cb_cls = cb_cls;
+  GNUNET_CRYPTO_eddsa_key_get_public (&purse_priv->eddsa_priv,
+                                      &purse_pub.eddsa_pub);
+  GNUNET_assert (GNUNET_YES ==
+                 TEAH_handle_is_ready (exchange));
+  {
+    char pub_str[sizeof (purse_pub) * 2];
+    char *end;
+
+    end = GNUNET_STRINGS_data_to_string (&purse_pub,
+                                         sizeof (purse_pub),
+                                         pub_str,
+                                         sizeof (pub_str));
+    *end = '\0';
+    GNUNET_snprintf (arg_str,
+                     sizeof (arg_str),
+                     "/purses/%s",
+                     pub_str);
+  }
+  pdh->url = TEAH_path_to_url (exchange,
+                               arg_str);
+  if (NULL == pdh->url)
+  {
+    GNUNET_break (0);
+    GNUNET_free (pdh);
+    return NULL;
+  }
+  TALER_wallet_purse_delete_sign (purse_priv,
+                                  &purse_sig);
+  {
+    char *delete_str;
+    char *xhdr;
+
+    delete_str =
+      GNUNET_STRINGS_data_to_string_alloc (&purse_sig,
+                                           sizeof (purse_sig));
+    GNUNET_asprintf (&xhdr,
+                     "Taler-Purse-Signature: %s",
+                     delete_str);
+    GNUNET_free (delete_str);
+    pdh->xhdr = curl_slist_append (NULL,
+                                   xhdr);
+    GNUNET_free (xhdr);
+  }
+  eh = TALER_EXCHANGE_curl_easy_get_ (pdh->url);
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "URL for purse delete: `%s'\n",
+              pdh->url);
+  ctx = TEAH_handle_to_context (exchange);
+  pdh->job = GNUNET_CURL_job_add2 (ctx,
+                                   eh,
+                                   pdh->xhdr,
+                                   &handle_purse_delete_finished,
+                                   pdh);
+  return pdh;
+}
+
+
+void
+TALER_EXCHANGE_purse_delete_cancel (
+  struct TALER_EXCHANGE_PurseDeleteHandle *pdh)
+{
+  if (NULL != pdh->job)
+  {
+    GNUNET_CURL_job_cancel (pdh->job);
+    pdh->job = NULL;
+  }
+  curl_slist_free_all (pdh->xhdr);
+  GNUNET_free (pdh->url);
+  GNUNET_free (pdh);
+}
+
+
+/* end of exchange_api_purse_delete.c */