start with /kyc support in libtalermerchant

3 files changed, 486 insertions, 2 deletions

diff --git a/src/include/taler_merchant_service.h b/src/include/taler_merchant_service.h
index cc3063f6..82e81b4b 100644
--- a/src/include/taler_merchant_service.h
+++ b/src/include/taler_merchant_service.h
@@ -3497,8 +3497,8 @@ TALER_MERCHANT_merchant_tip_get (struct GNUNET_CURL_Context *ctx,
  * @param tgh handle to the request to be canceled
  */
 void
-TALER_MERCHANT_merchant_tip_get_cancel (struct
-                                        TALER_MERCHANT_TipMerchantGetHandle *tgh);
+TALER_MERCHANT_merchant_tip_get_cancel (
+  struct TALER_MERCHANT_TipMerchantGetHandle *tgh);
 
 
 /**
@@ -3734,4 +3734,181 @@ TALER_MERCHANT_tip_pickup2_cancel (
   struct TALER_MERCHANT_TipPickup2Handle *tp);
 
 
+
+/* ********************* /kyc ************************** */
+
+/**
+ * Handle for GETing the KYC status of instance(s).
+ */
+struct TALER_MERCHANT_KycGetHandle;
+
+
+/**
+ * Information about KYC actions the merchant still must perform.
+ */
+struct TALER_MERCHANT_AccountKycRedirectDetail
+{
+
+  /**
+   * URL that the user should open in a browser to
+   * proceed with the KYC process (as returned
+   * by the exchange's /kyc-check/ endpoint).
+   */
+  const char *kyc_url;
+
+  /**
+   * Base URL of the exchange this is about.
+   */
+  const char *exchange_url;
+
+  /**
+   * Our bank wire account this is about.
+   */
+  const char *payto_uri;
+};
+
+
+/**
+ * Information about KYC status failures at the exchange.
+ */
+struct TALER_MERCHANT_ExchangeKycFailureDetail
+{
+  /**
+   * Base URL of the exchange this is about.
+   */
+  const char *exchange_url;
+
+  /**
+   * Error code indicating errors the exchange
+   * returned, or #TALER_EC_INVALID for none.
+   */
+  enum TALER_ErrorCode exchange_code;
+
+  /**
+   * HTTP status code returned by the exchange when we asked for
+   * information about the KYC status.
+   * 0 if there was no response at all.
+   */
+  unsigned int exchange_http_status;
+};
+
+
+/**
+ * Details in a response to a GET /kyc request.
+ */
+struct TALER_MERCHANT_KycResponse
+{
+  struct TALER_MERCHANT_HttpResponse hr;
+
+  /**
+   * Response details.
+   */
+  union
+  {
+    /**
+     * Information returned if the status was #MHD_HTTP_ACCEPTED,
+     * #MHD_HTTP_BAD_GATEWAY or #MHD_HTTP_GATEWAY_TIMEOUT.
+     */
+    struct
+    {
+
+      /**
+       * Array with information about KYC actions the merchant still must perform.
+       */
+      struct TALER_MERCHANT_AccountKycRedirectDetail *pending_kycs;
+
+      /**
+       * Array with information about KYC failures at the exchange.
+       */
+      struct TALER_MERCHANT_ExchangeKycFailureDetail *timeout_kycs;
+
+      /**
+       * Length of the @e pending_kycs array.
+       */
+      unsigned int pending_kycs_length;
+
+      /**
+       * Length of the @e timeout_kycs array.
+       */
+      unsigned int timeout_kycs_length;
+    } kyc_status;
+
+  } details;
+
+};
+
+
+/**
+ * Callback to with a response from a GET [/private]/kyc request
+ *
+ * @param cls closure
+ * @param kr response details
+ */
+typedef void
+(*TALER_MERCHANT_KycGetCallback) (
+  void *cls,
+  const struct TALER_MERCHANT_KycResponse *kr);
+
+
+/**
+ * Issue a GET /private/kycs/$KYC_ID (private variant) request to the backend.
+ * Returns KYC status of bank accounts.
+ *
+ * @param ctx execution context
+ * @param backend_url base URL of the merchant backend
+ * @param h_wire which bank account to query, NULL for all
+ * @param exchange_url which exchange to query, NULL for all
+ * @param timeout how long to wait for a (positive) reply
+ * @param cb function to call with the result
+ * @param cb_cls closure for @a cb
+ * @return handle for this operation, NULL upon errors
+ */
+struct TALER_MERCHANT_KycGetHandle *
+TALER_MERCHANT_kyc_get (struct GNUNET_CURL_Context *ctx,
+                        const char *backend_url,
+                        const struct GNUNET_HashCode *h_wire,
+                        const char *exchange_url,
+                        struct GNUNET_TIME_Relative timeout,
+                        TALER_MERCHANT_KycGetCallback cb,
+                        void *cb_cls);
+
+
+/**
+ * Issue a GET /management/instances/$INSTANCE/kyc request to the backend.
+ * Returns KYC status of bank accounts.
+ *
+ * @param ctx execution context
+ * @param backend_url base URL of the merchant backend
+ * @param instance_id specific instance to query
+ * @param h_wire which bank account to query, NULL for all
+ * @param exchange_url which exchange to query, NULL for all
+ * @param timeout how long to wait for a (positive) reply
+ * @param cb function to call with the result
+ * @param cb_cls closure for @a cb
+ * @return handle for this operation, NULL upon errors
+ */
+struct TALER_MERCHANT_KycGetHandle *
+TALER_MERCHANT_management_kyc_get (struct GNUNET_CURL_Context *ctx,
+                                   const char *backend_url,
+                                   const char *instance_id,
+                                   const struct GNUNET_HashCode *h_wire,
+                                   const char *exchange_url,
+                                   struct GNUNET_TIME_Relative timeout,
+                                   TALER_MERCHANT_KycGetCallback cb,
+                                   void *cb_cls);
+
+
+/**
+ * Cancel a GET [/private]/kyc/$KYC_ID request.
+ *
+ * @param kyc handle to the request to be canceled
+ */
+void
+TALER_MERCHANT_kyc_get_cancel (
+  struct TALER_MERCHANT_KycGetHandle *kyc);
+
+
+
+
+
 #endif  /* _TALER_MERCHANT_SERVICE_H */
diff --git a/src/lib/Makefile.am b/src/lib/Makefile.am
index 52d6dd84..8b906e16 100644
--- a/src/lib/Makefile.am
+++ b/src/lib/Makefile.am
@@ -23,6 +23,7 @@ libtalermerchant_la_SOURCES = \
   merchant_api_get_config.c \
   merchant_api_get_instance.c \
   merchant_api_get_instances.c \
+  merchant_api_get_kyc.c \
   merchant_api_get_orders.c \
   merchant_api_get_product.c \
   merchant_api_get_products.c \
diff --git a/src/lib/merchant_api_get_kyc.c b/src/lib/merchant_api_get_kyc.c
new file mode 100644
index 00000000..816b3cc0
--- /dev/null
+++ b/src/lib/merchant_api_get_kyc.c
@@ -0,0 +1,306 @@
+/*
+  This file is part of TALER
+  Copyright (C) 2021 Taler Systems SA
+
+  TALER is free software; you can redistribute it and/or modify it under the
+  terms of the GNU Lesser General Public License as published by the Free Software
+  Foundation; either version 2.1, 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 Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License along with
+  TALER; see the file COPYING.LGPL.  If not, see
+  <http://www.gnu.org/licenses/>
+*/
+/**
+ * @file merchant_api_get_kyc.c
+ * @brief Implementation of the GET /kyc request of the merchant's HTTP API
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include <curl/curl.h>
+#include <jansson.h>
+#include <microhttpd.h> /* just for HTTP status codes */
+#include <gnunet/gnunet_util_lib.h>
+#include <gnunet/gnunet_curl_lib.h>
+#include "taler_merchant_service.h"
+#include <taler/taler_json_lib.h>
+#include <taler/taler_signatures.h>
+
+
+/**
+ * Handle for a GET /kyc operation.
+ */
+struct TALER_MERCHANT_KycGetHandle
+{
+  /**
+   * The url for this request.
+   */
+  char *url;
+
+  /**
+   * Handle for the request.
+   */
+  struct GNUNET_CURL_Job *job;
+
+  /**
+   * Function to call with the result.
+   */
+  TALER_MERCHANT_KycGetCallback cb;
+
+  /**
+   * Closure for @a cb.
+   */
+  void *cb_cls;
+
+  /**
+   * Reference to the execution context.
+   */
+  struct GNUNET_CURL_Context *ctx;
+
+};
+
+
+/**
+ * Parse @a kyc response and call the continuation on success.
+ *
+ * @param kyc operation handle
+ * @param[in,out] kr response details
+ * @param pends pending_kycs array from the reply
+ * @param touts timeout_kycs array from the reply
+ * @return #GNUNET_OK on success (callback was called)
+ */
+static enum GNUNET_GenericReturnValue
+parse_kyc (struct TALER_MERCHANT_KycGetHandle *kyc,
+           struct TALER_MERCHANT_KycResponse *kr,
+           json_t *pends,
+           json_t *touts)
+{
+  // FIXME...
+  GNUNET_break (0);
+  return GNUNET_SYSERR;
+}
+
+
+/**
+ * Function called when we're done processing the
+ * HTTP /kyc request.
+ *
+ * @param cls the `struct TALER_MERCHANT_KycGetHandle`
+ * @param response_code HTTP response code, 0 on error
+ * @param response response body, NULL if not in JSON
+ */
+static void
+handle_get_kyc_finished (void *cls,
+                         long response_code,
+                         const void *response)
+{
+  struct TALER_MERCHANT_KycGetHandle *kyc = cls;
+  const json_t *json = response;
+  struct TALER_MERCHANT_KycResponse kr = {
+    .hr.http_status = (unsigned int) response_code,
+    .hr.reply = json
+  };
+
+  kyc->job = NULL;
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Got /kyc response with status code %u\n",
+              (unsigned int) response_code);
+  switch (response_code)
+  {
+  case MHD_HTTP_NO_CONTENT:
+    break;
+  case MHD_HTTP_ACCEPTED:
+  case MHD_HTTP_BAD_GATEWAY:
+  case MHD_HTTP_GATEWAY_TIMEOUT:
+    {
+      json_t *pends;
+      json_t *touts;
+      struct GNUNET_JSON_Specification spec[] = {
+        GNUNET_JSON_spec_json ("pending_kycs",
+                               &pends),
+        GNUNET_JSON_spec_json ("timeout_kycs",
+                               &touts),
+        GNUNET_JSON_spec_end ()
+      };
+
+      if (GNUNET_OK !=
+          GNUNET_JSON_parse (json,
+                             spec,
+                             NULL, NULL))
+      {
+        kr.hr.http_status = 0;
+        kr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
+        break;
+      }
+      if ( (! json_is_array (pends)) ||
+           (! json_is_array (touts)) ||
+           (GNUNET_OK !=
+            parse_kyc (kyc,
+                       &kr,
+                       pends,
+                       touts)) )
+      {
+        kr.hr.http_status = 0;
+        kr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE;
+        break;
+      }
+      /* parse_kyc called the continuation already */
+      GNUNET_JSON_parse_free (spec);
+      TALER_MERCHANT_kyc_get_cancel (kyc);
+      return;
+    }
+  case MHD_HTTP_UNAUTHORIZED:
+    kr.hr.ec = TALER_JSON_get_error_code (json);
+    kr.hr.hint = TALER_JSON_get_error_hint (json);
+    /* Nothing really to verify, merchant says we need to authenticate. */
+    break;
+  default:
+    /* unexpected response code */
+    kr.hr.ec = TALER_JSON_get_error_code (json);
+    kr.hr.hint = TALER_JSON_get_error_hint (json);
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Unexpected response code %u/%d\n",
+                (unsigned int) response_code,
+                (int) kr.hr.ec);
+    break;
+  }
+  kyc->cb (kyc->cb_cls,
+           &kr);
+  TALER_MERCHANT_kyc_get_cancel (kyc);
+}
+
+
+/**
+ * Issue a GET KYC request to the backend.
+ * Returns KYC status of bank accounts.
+ *
+ * @param ctx execution context
+ * @param[in] url URL to use for the request, consumed!
+ * @param h_wire which bank account to query, NULL for all
+ * @param exchange_url which exchange to query, NULL for all
+ * @param timeout how long to wait for a (positive) reply
+ * @param cb function to call with the result
+ * @param cb_cls closure for @a cb
+ * @return handle for this operation, NULL upon errors
+ */
+static struct TALER_MERCHANT_KycGetHandle *
+kyc_get (struct GNUNET_CURL_Context *ctx,
+         char *url,
+         const struct GNUNET_HashCode *h_wire,
+         const char *exchange_url,
+         struct GNUNET_TIME_Relative timeout,
+         TALER_MERCHANT_KycGetCallback cb,
+         void *cb_cls)
+{
+  struct TALER_MERCHANT_KycGetHandle *kyc;
+  CURL *eh;
+  char timeout_ms[32];
+
+  kyc = GNUNET_new (struct TALER_MERCHANT_KycGetHandle);
+  kyc->ctx = ctx;
+  kyc->cb = cb;
+  kyc->cb_cls = cb_cls;
+  GNUNET_snprintf (timeout_ms,
+                   sizeof (timeout_ms),
+                   "%llu",
+                   (unsigned long long) (timeout.rel_value_us / GNUNET_TIME_UNIT_MILLISECONDS.rel_value_us));
+  kyc->url = TALER_url_join (url,
+                             "h_wire",
+                             NULL == h_wire
+                             ? NULL
+                             : GNUNET_h2s_full (h_wire),
+                             "exchange_url",
+                             NULL == exchange_url
+                             ? NULL
+                             : exchange_url,
+                             "timeout_ms",
+                             GNUNET_TIME_relative_is_zero (timeout)
+                             ? NULL
+                             : timeout_ms,
+                             NULL);
+  GNUNET_free (url);
+  if (NULL == kyc->url)
+  {
+    GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+                "Could not construct request URL.\n");
+    GNUNET_free (kyc);
+    return NULL;
+  }
+  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+              "Requesting URL '%s'\n",
+              kyc->url);
+  eh = curl_easy_init ();
+  GNUNET_assert (CURLE_OK ==
+                 curl_easy_setopt (eh,
+                                   CURLOPT_URL,
+                                   kyc->url));
+  kyc->job = GNUNET_CURL_job_add (ctx,
+                                  eh,
+                                  &handle_get_kyc_finished,
+                                  kyc);
+  return kyc;
+}
+
+
+struct TALER_MERCHANT_KycGetHandle *
+TALER_MERCHANT_kyc_get (struct GNUNET_CURL_Context *ctx,
+                        const char *backend_url,
+                        const struct GNUNET_HashCode *h_wire,
+                        const char *exchange_url,
+                        struct GNUNET_TIME_Relative timeout,
+                        TALER_MERCHANT_KycGetCallback cb,
+                        void *cb_cls)
+{
+  char *url;
+
+  GNUNET_asprintf (&url,
+                   "%sprivate/kyc",
+                   backend_url);
+  return kyc_get (ctx,
+                  url,
+                  h_wire,
+                  exchange_url,
+                  timeout,
+                  cb,
+                  cb_cls);
+}
+
+
+struct TALER_MERCHANT_KycGetHandle *
+TALER_MERCHANT_management_kyc_get (struct GNUNET_CURL_Context *ctx,
+                                   const char *backend_url,
+                                   const char *instance_id,
+                                   const struct GNUNET_HashCode *h_wire,
+                                   const char *exchange_url,
+                                   struct GNUNET_TIME_Relative timeout,
+                                   TALER_MERCHANT_KycGetCallback cb,
+                                   void *cb_cls)
+{
+  char *url;
+
+  GNUNET_asprintf (&url,
+                   "%smanagement/instances/%s/kyc",
+                   backend_url,
+                   instance_id);
+  return kyc_get (ctx,
+                  url,
+                  h_wire,
+                  exchange_url,
+                  timeout,
+                  cb,
+                  cb_cls);
+}
+
+
+void
+TALER_MERCHANT_kyc_get_cancel (
+  struct TALER_MERCHANT_KycGetHandle *kyc)
+{
+  if (NULL != kyc->job)
+    GNUNET_CURL_job_cancel (kyc->job);
+  GNUNET_free (kyc->url);
+  GNUNET_free (kyc);
+}