WIP: policy_details handling continued

- policy details generated on deposit/batch-deposit requests
- insert or update of policy details in the DB
- accumulation of amounts of multiple deposits for the same
  policy_details

6 files changed, 316 insertions, 200 deletions

diff --git a/src/exchange/taler-exchange-httpd.c b/src/exchange/taler-exchange-httpd.c
index 32cbd8dd..1cbaee96 100644
--- a/src/exchange/taler-exchange-httpd.c
+++ b/src/exchange/taler-exchange-httpd.c
@@ -1041,138 +1041,6 @@ handle_post_auditors (struct TEH_RequestContext *rc,
                                root);
 }
 
-
-/**
- * Handle GET "/extensions/..." requests.
- *
- * @param rc request context
- * @param args array of additional options
- * @return MHD result code
- */
-static MHD_RESULT
-handle_get_extensions (struct TEH_RequestContext *rc,
-                       const char *const args[])
-{
-  const struct TALER_Extension *ext = NULL;
-
-  if (NULL == args[0])
-  {
-    GNUNET_break_op (0);
-    return r404 (rc->connection,
-                 "/extensions/$EXTENSION");
-  }
-
-  ext = TALER_extensions_get_by_name (args[0]);
-  if (NULL == ext)
-  {
-    GNUNET_break_op (0);
-    return r404 (rc->connection,
-                 "/extensions/$EXTENSION unknown");
-  }
-
-  if (NULL == ext->policy_get_handler)
-    return TALER_MHD_reply_with_error (rc->connection,
-                                       MHD_HTTP_NOT_IMPLEMENTED,
-                                       TALER_EC_EXCHANGE_GENERIC_OPERATION_UNKNOWN,
-                                       "GET /extensions/$EXTENSION not supported");
-
-  return ext->policy_get_handler (
-    rc->connection,
-    &args[1]);
-}
-
-
-/* @brief function pointer for TALER_extension.check */
-static enum GNUNET_GenericReturnValue
-check_serial_ids (
-  struct GNUNET_HashCode serial_ids[],
-  size_t size)
-{
-  for (size_t i = 0; i < size; i++)
-    GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-                "Got to check serial_id: %s\n",
-                GNUNET_h2s (&serial_ids[i]));
-  return GNUNET_OK;
-}
-
-
-/**
- * Handle POST "/extensions/..." requests.
- *
- * @param rc request context
- * @param root uploaded JSON data
- * @param args array of additional options
- * @return MHD result code
- */
-static MHD_RESULT
-handle_post_extensions (struct TEH_RequestContext *rc,
-                        const json_t *root,
-                        const char *const args[])
-{
-  const struct TALER_Extension *ext = NULL;
-  json_t *output;
-
-  if (NULL == args[0])
-  {
-    GNUNET_break_op (0);
-    return r404 (rc->connection,
-                 "/extensions/$EXTENSION");
-  }
-
-  ext = TALER_extensions_get_by_name (args[0]);
-  if (NULL == ext)
-  {
-    GNUNET_break_op (0);
-    return r404 (rc->connection,
-                 "/extensions/$EXTENSION unknown");
-  }
-
-  if (NULL == ext->policy_post_handler)
-    return TALER_MHD_reply_with_error (rc->connection,
-                                       MHD_HTTP_NOT_IMPLEMENTED,
-                                       TALER_EC_EXCHANGE_GENERIC_OPERATION_UNKNOWN,
-                                       "POST /extensions/$EXTENSION not supported");
-
-  {
-    enum GNUNET_GenericReturnValue ret;
-    struct TALER_PolicyFulfilmentOutcome *outcome;
-
-    ret = ext->policy_post_handler (root,
-                                    &args[1],
-                                    &check_serial_ids,
-                                    &outcome,
-                                    &output);
-
-    if (GNUNET_OK != ret)
-    {
-      TALER_policy_fulfilment_outcome_free (outcome);
-      TALER_MHD_reply_json_steal (
-        rc->connection,
-        output,
-        MHD_HTTP_BAD_REQUEST);
-    }
-
-    /* TODO: deal with outcome */
-    {
-      for (size_t i = 0; i < outcome->len; i++)
-      {
-        GNUNET_log (GNUNET_ERROR_TYPE_INFO,
-                    "Got outcome for serial_id: %s, state: %s, amount: %s\n",
-                    GNUNET_h2s (&outcome->positions[i].serial_id),
-                    TALER_policy_fulfilment_state_str (
-                      outcome->positions[i].state),
-                    TALER_amount_to_string (&outcome->positions[i].new_amount));
-      }
-    }
-
-  }
-
-  return TALER_MHD_reply_json_steal (rc->connection,
-                                     output,
-                                     MHD_HTTP_OK);
-}
-
-
 /**
  * Handle incoming HTTP request.
  *
@@ -1393,15 +1261,8 @@ handle_mhd_request (void *cls,
     /* extensions endpoints */
     {
       .url = "extensions",
-      .method = MHD_HTTP_METHOD_GET,
-      .handler.get = &handle_get_extensions,
-      .nargs = 4, /* Arbitrary upper bound */
-      .nargs_is_upper_bound = true,
-    },
-    {
-      .url = "extensions",
       .method = MHD_HTTP_METHOD_POST,
-      .handler.post = &handle_post_extensions,
+      .handler.post = &TEH_extensions_post_handler,
       .nargs = 4, /* Arbitrary upper bound */
       .nargs_is_upper_bound = true,
     },
diff --git a/src/exchange/taler-exchange-httpd_batch-deposit.c b/src/exchange/taler-exchange-httpd_batch-deposit.c
index d4a9666e..14267e2a 100644
--- a/src/exchange/taler-exchange-httpd_batch-deposit.c
+++ b/src/exchange/taler-exchange-httpd_batch-deposit.c
@@ -90,8 +90,12 @@ struct BatchDepositContext
    * Additional details for policy relevant for this
    * deposit operation, possibly NULL!
    */
-  json_t *policy_details;
-  bool has_policy_details;
+  json_t *policy_json;
+
+  /**
+   * Will be true if policy_json were provided
+   */
+  bool has_policy;
 
   /**
    * Hash over @e policy_details, might be all zero;
@@ -99,6 +103,19 @@ struct BatchDepositContext
   struct TALER_ExtensionPolicyHashP h_policy;
 
   /**
+   * If @e policy_json was present, the corresponding policy extension
+   * calculates these details.  These will be persisted in the policy_details
+   * table.
+   */
+  struct TALER_PolicyDetails policy_details;
+
+  /**
+   * When @e policy_details are persisted, this contains the id of the record
+   * in the policy_details table.
+   */
+  uint64_t policy_details_serial_id;
+
+  /**
    * Time when this request was generated.  Used, for example, to
    * assess when (roughly) the income was achieved for tax purposes.
    * Note that the Exchange will only check that the timestamp is not "too
@@ -174,7 +191,7 @@ again:
            &TEH_keys_exchange_sign_,
            &bdc->h_contract_terms,
            &bdc->h_wire,
-           bdc->has_policy_details ? &bdc->h_policy : NULL,
+           bdc->has_policy ? &bdc->h_policy : NULL,
            bdc->exchange_timestamp,
            bdc->wire_deadline,
            bdc->refund_deadline,
@@ -247,6 +264,21 @@ batch_deposit_transaction (void *cls,
   bool balance_ok;
   bool in_conflict;
 
+
+  /* If the deposit has a policy associated to it, persist it.  This will
+   * insert or update the record. */
+  if (dc->has_policy)
+  {
+    qs = TEH_plugin->persist_policy_details (TEH_plugin->cls,
+                                             &dc->policy_details,
+                                             &dc->policy_details_serial_id,
+					     &dc->policy_details.accumulated_total,
+					     &dc->policy_details.fulfillment_state);
+    if (qs < 0)
+      return qs;
+  }
+
+  /* deposit the individutal coins */
   for (unsigned int i = 0; i<dc->num_coins; i++)
   {
     const struct TALER_EXCHANGEDB_Deposit *deposit = &dc->deposits[i];
@@ -258,13 +290,19 @@ batch_deposit_transaction (void *cls,
                               mhd_ret);
     if (qs < 0)
       return qs;
-    qs = TEH_plugin->do_deposit (TEH_plugin->cls,
-                                 deposit,
-                                 known_coin_id,
-                                 &dc->h_payto,
-                                 &dc->exchange_timestamp,
-                                 &balance_ok,
-                                 &in_conflict);
+
+    qs = TEH_plugin->do_deposit (
+      TEH_plugin->cls,
+      deposit,
+      known_coin_id,
+      &dc->h_payto,
+      (dc->has_policy)
+         ?  &dc->policy_details_serial_id
+         : NULL,
+      &dc->exchange_timestamp,
+      &balance_ok,
+      &in_conflict);
+
     if (qs < 0)
     {
       if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
@@ -474,7 +512,7 @@ parse_coin (struct MHD_Connection *connection,
                                    &dc->h_wire,
                                    &dc->h_contract_terms,
                                    &deposit->coin.h_age_commitment,
-                                   dc->has_policy_details ? &dc->h_policy :
+                                   dc->has_policy ? &dc->h_policy :
                                    NULL,
                                    &deposit->coin.denom_pub_hash,
                                    dc->timestamp,
@@ -501,7 +539,7 @@ parse_coin (struct MHD_Connection *connection,
      but rather insert them ONCE and then per-coin only use
      the resulting extension UUID/serial; so the data structure
      here should be changed once we look at extensions in earnest.  */
-  deposit->policy_details = dc->policy_details;
+  deposit->policy_json = dc->policy_json;
   deposit->timestamp = dc->timestamp;
   deposit->refund_deadline = dc->refund_deadline;
   deposit->wire_deadline = dc->wire_deadline;
@@ -518,7 +556,7 @@ TEH_handler_batch_deposit (struct TEH_RequestContext *rc,
   struct BatchDepositContext dc;
   json_t *coins;
   bool no_refund_deadline = true;
-  bool no_policy_details = true;
+  bool no_policy_json = true;
   struct GNUNET_JSON_Specification spec[] = {
     GNUNET_JSON_spec_string ("merchant_payto_uri",
                              &dc.payto_uri),
@@ -532,8 +570,8 @@ TEH_handler_batch_deposit (struct TEH_RequestContext *rc,
                            &coins),
     GNUNET_JSON_spec_mark_optional (
       GNUNET_JSON_spec_json ("policy",
-                             &dc.policy_details),
-      &no_policy_details),
+                             &dc.policy_json),
+      &no_policy_json),
     GNUNET_JSON_spec_timestamp ("timestamp",
                                 &dc.timestamp),
     GNUNET_JSON_spec_mark_optional (
@@ -564,7 +602,7 @@ TEH_handler_batch_deposit (struct TEH_RequestContext *rc,
     return MHD_YES;   /* failure */
   }
 
-  dc.has_policy_details = ! no_policy_details;
+  dc.has_policy = ! no_policy_json;
 
   /* validate merchant's wire details (as far as we can) */
   {
@@ -610,11 +648,26 @@ TEH_handler_batch_deposit (struct TEH_RequestContext *rc,
   TALER_merchant_wire_signature_hash (dc.payto_uri,
                                       &dc.wire_salt,
                                       &dc.h_wire);
-  if (dc.has_policy_details)
+
+  /* handle policy, if present */
+  if (dc.has_policy)
   {
-    TALER_deposit_policy_hash (dc.policy_details,
+    const char *error_hint = NULL;
+
+    if (GNUNET_OK !=
+        TALER_extensions_create_policy_details (
+          dc.policy_json,
+          &dc.policy_details,
+          &error_hint))
+      return TALER_MHD_reply_with_error (connection,
+                                         MHD_HTTP_BAD_REQUEST,
+                                         TALER_EC_EXCHANGE_DEPOSITS_POLICY_NOT_ACCEPTED,
+                                         error_hint);
+
+    TALER_deposit_policy_hash (dc.policy_json,
                                &dc.h_policy);
   }
+
   dc.num_coins = json_array_size (coins);
   if (0 == dc.num_coins)
   {
@@ -651,6 +704,8 @@ TEH_handler_batch_deposit (struct TEH_RequestContext *rc,
       GNUNET_JSON_parse_free (spec);
       return (GNUNET_NO == res) ? MHD_YES : MHD_NO;
     }
+
+    /* FIXME: sum all contributions for the policy_details.accumulated_total */
   }
 
   dc.exchange_timestamp = GNUNET_TIME_timestamp_get ();
diff --git a/src/exchange/taler-exchange-httpd_deposit.c b/src/exchange/taler-exchange-httpd_deposit.c
index 12741c6b..f44775c0 100644
--- a/src/exchange/taler-exchange-httpd_deposit.c
+++ b/src/exchange/taler-exchange-httpd_deposit.c
@@ -132,6 +132,12 @@ struct DepositContext
    */
   uint64_t known_coin_id;
 
+  /**
+   * When deposit->has_policy is true, and deposit->policy_details are
+   * persisted, this contains the id of the record in the policy_details table.
+   */
+  uint64_t policy_details_serial_id;
+
 };
 
 
@@ -165,14 +171,36 @@ deposit_transaction (void *cls,
   if (qs < 0)
     return qs;
 
+  /* If the deposit has a policy associated to it, persist it.  This will
+   * insert or update the record. */
+  if (dc->deposit->has_policy)
+  {
+    struct TALER_Amount accumulated_total;
+    enum TALER_PolicyFulfillmentState fulfillment_state;
+    qs = TEH_plugin->persist_policy_details (TEH_plugin->cls,
+                                             &dc->deposit->policy_details,
+                                             &dc->policy_details_serial_id,
+                                             &accumulated_total,
+                                             &fulfillment_state);
+
+    /* FIXME: what to do with accumulated_total and fulfillment_state ? */
+
+    if (qs < 0)
+      return qs;
+  }
+
+  qs = TEH_plugin->do_deposit (
+    TEH_plugin->cls,
+    dc->deposit,
+    dc->known_coin_id,
+    &dc->h_payto,
+    (dc->deposit->has_policy)
+             ? &dc->policy_details_serial_id
+             : NULL,
+    &dc->exchange_timestamp,
+    &balance_ok,
+    &in_conflict);
 
-  qs = TEH_plugin->do_deposit (TEH_plugin->cls,
-                               dc->deposit,
-                               dc->known_coin_id,
-                               &dc->h_payto,
-                               &dc->exchange_timestamp,
-                               &balance_ok,
-                               &in_conflict);
   if (qs < 0)
   {
     if (GNUNET_DB_STATUS_SOFT_ERROR == qs)
@@ -219,7 +247,7 @@ TEH_handler_deposit (struct MHD_Connection *connection,
   struct TALER_EXCHANGEDB_Deposit deposit;
   const char *payto_uri;
   struct TALER_ExtensionPolicyHashP *ph_policy = NULL;
-  bool no_policy_details;
+  bool no_policy_json;
   struct GNUNET_JSON_Specification spec[] = {
     GNUNET_JSON_spec_string ("merchant_payto_uri",
                              &payto_uri),
@@ -255,8 +283,8 @@ TEH_handler_deposit (struct MHD_Connection *connection,
                                 &deposit.wire_deadline),
     GNUNET_JSON_spec_mark_optional (
       GNUNET_JSON_spec_json ("policy",
-                             &deposit.policy_details),
-      &no_policy_details),
+                             &deposit.policy_json),
+      &no_policy_json),
     GNUNET_JSON_spec_end ()
   };
   struct TALER_MerchantWireHashP h_wire;
@@ -284,7 +312,7 @@ TEH_handler_deposit (struct MHD_Connection *connection,
   }
 
   /* set the state of the policy presence in the deposit struct */
-  deposit.has_policy_details = ! no_policy_details;
+  deposit.has_policy = ! no_policy_json;
 
   /* validate merchant's wire details (as far as we can) */
   {
@@ -333,28 +361,6 @@ TEH_handler_deposit (struct MHD_Connection *connection,
                                       &h_wire);
   dc.deposit = &deposit;
 
-  /* Check policy */
-  if (deposit.has_policy_details)
-  {
-    const char *error_hint = NULL;
-    enum TALER_PolicyFulfilmentState state_on_timeout;
-
-    if (GNUNET_OK !=
-        TALER_extensions_extract_meta_data_from_policy_details (
-          deposit.policy_details,
-          &deposit.policy_serial_id,
-          &deposit.policy_deadline,
-          &state_on_timeout,
-          &error_hint))
-      return TALER_MHD_reply_with_error (connection,
-                                         MHD_HTTP_BAD_REQUEST,
-                                         TALER_EC_EXCHANGE_DEPOSITS_POLICY_NOT_ACCEPTED,
-                                         error_hint);
-
-    GNUNET_assert (TALER_PolicyFulfilmentStateMax >= state_on_timeout);
-    deposit.policy_state_on_timeout = state_on_timeout;
-  }
-
   /* new deposit */
   dc.exchange_timestamp = GNUNET_TIME_timestamp_get ();
   /* check denomination exists and is valid */
@@ -420,13 +426,6 @@ TEH_handler_deposit (struct MHD_Connection *connection,
                                          NULL);
     }
 
-    if (deposit.has_policy_details)
-    {
-      TALER_deposit_policy_hash (deposit.policy_details,
-                                 &deposit.h_policy);
-      ph_policy = &deposit.h_policy;
-    }
-
     deposit.deposit_fee = dk->meta.fees.deposit;
     /* check coin signature */
     switch (dk->denom_pub.cipher)
@@ -463,6 +462,27 @@ TEH_handler_deposit (struct MHD_Connection *connection,
                                        NULL);
   }
 
+  /* Check policy input and create policy details */
+  if (deposit.has_policy)
+  {
+    const char *error_hint = NULL;
+
+    if (GNUNET_OK !=
+        TALER_extensions_create_policy_details (
+          deposit.policy_json,
+          &deposit.policy_details,
+          &error_hint))
+      return TALER_MHD_reply_with_error (connection,
+                                         MHD_HTTP_BAD_REQUEST,
+                                         TALER_EC_EXCHANGE_DEPOSITS_POLICY_NOT_ACCEPTED,
+                                         error_hint);
+
+    TALER_deposit_policy_hash (deposit.policy_json,
+                               &deposit.h_policy);
+    ph_policy = &deposit.h_policy;
+  }
+
+
   TEH_METRICS_num_verifications[TEH_MT_SIGNATURE_EDDSA]++;
   if (GNUNET_OK !=
       TALER_wallet_deposit_verify (&deposit.amount_with_fee,
diff --git a/src/exchange/taler-exchange-httpd_extensions.c b/src/exchange/taler-exchange-httpd_extensions.c
index e8d3e4af..8e8f0e01 100644
--- a/src/exchange/taler-exchange-httpd_extensions.c
+++ b/src/exchange/taler-exchange-httpd_extensions.c
@@ -14,7 +14,7 @@
 */
 /**
  * @file taler-exchange-httpd_extensions.c
- * @brief Handle extensions (age-restriction, peer2peer)
+ * @brief Handle extensions (age-restriction, policy extensions)
  * @author Özgür Kesim
  */
 #include "platform.h"
@@ -232,4 +232,168 @@ TEH_extensions_done ()
 }
 
 
+/*
+ * @brief Execute database transactions for /extensions/policy_* POST requests.
+ *
+ * @param cls a `struct TALER_PolicyFulfillmentOutcome`
+ * @param connection MHD request context
+ * @param[out] mhd_ret set to MHD status on error
+ * @return transaction status
+ */
+static enum GNUNET_DB_QueryStatus
+policy_fulfillment_transaction (
+  void *cls,
+  struct MHD_Connection *connection,
+  MHD_RESULT *mhd_ret)
+{
+  struct TALER_PolicyFulfillmentTransactionData *fulfillment = cls;
+
+  return TEH_plugin->add_policy_fulfillment_proof (TEH_plugin->cls,
+                                                   fulfillment);
+}
+
+
+MHD_RESULT
+TEH_extensions_post_handler (
+  struct TEH_RequestContext *rc,
+  const json_t *root,
+  const char *const args[])
+{
+  const struct TALER_Extension *ext = NULL;
+  json_t *output;
+  struct TALER_PolicyDetails *policy_details = NULL;
+  size_t policy_details_count = 0;
+
+
+  if (NULL == args[0])
+  {
+    GNUNET_break_op (0);
+    return TALER_MHD_reply_with_error (rc->connection,
+                                       MHD_HTTP_NOT_FOUND,
+                                       TALER_EC_EXCHANGE_GENERIC_OPERATION_UNKNOWN,
+                                       "/extensions/$EXTENSION");
+  }
+
+  ext = TALER_extensions_get_by_name (args[0]);
+  if (NULL == ext)
+  {
+    GNUNET_break_op (0);
+    return TALER_MHD_reply_with_error (rc->connection,
+                                       MHD_HTTP_NOT_FOUND,
+                                       TALER_EC_EXCHANGE_GENERIC_OPERATION_UNKNOWN,
+                                       "/extensions/$EXTENSION unknown");
+  }
+
+  if (NULL == ext->policy_post_handler)
+    return TALER_MHD_reply_with_error (rc->connection,
+                                       MHD_HTTP_NOT_IMPLEMENTED,
+                                       TALER_EC_EXCHANGE_GENERIC_OPERATION_UNKNOWN,
+                                       "POST /extensions/$EXTENSION not supported");
+
+  /*  Extract hash_codes and retrieve related policy_details from the DB */
+  {
+    enum GNUNET_GenericReturnValue ret;
+    enum GNUNET_DB_QueryStatus qs;
+    const char *error_msg;
+    struct GNUNET_HashCode *hcs;
+    size_t len;
+    json_t*val;
+    size_t idx;
+    json_t *jhash_codes = json_object_get (root,
+                                           "policy_hash_codes");
+    if (! json_is_array (jhash_codes))
+      return TALER_MHD_reply_with_error (rc->connection,
+                                         MHD_HTTP_BAD_REQUEST,
+                                         TALER_EC_EXCHANGE_GENERIC_OPERATION_UNKNOWN,
+                                         "policy_hash_codes are missing");
+
+    len = json_array_size (jhash_codes);
+    hcs = GNUNET_new_array (len,
+                            struct GNUNET_HashCode);
+    policy_details = GNUNET_new_array (len,
+                                       struct TALER_PolicyDetails);
+
+    json_array_foreach (jhash_codes, idx, val)
+    {
+      struct GNUNET_JSON_Specification spec[] = {
+        GNUNET_JSON_spec_fixed_auto (NULL, &hcs[idx]),
+        GNUNET_JSON_spec_end ()
+      };
+
+      ret = GNUNET_JSON_parse (val,
+                               spec,
+                               &error_msg,
+                               NULL);
+      if (GNUNET_OK != ret)
+        break;
+
+      qs = TEH_plugin->get_policy_details (TEH_plugin->cls,
+                                           &hcs[idx],
+                                           &policy_details[idx]);
+      if (qs < 0)
+      {
+        error_msg = "a policy_hash_code couldn't be found";
+        break;
+      }
+    }
+
+    GNUNET_free (hcs);
+    if (GNUNET_OK != ret)
+    {
+      GNUNET_free (policy_details);
+      return TALER_MHD_reply_with_error (rc->connection,
+                                         MHD_HTTP_BAD_REQUEST,
+                                         TALER_EC_EXCHANGE_GENERIC_OPERATION_UNKNOWN,
+                                         error_msg);
+    }
+  }
+
+
+  {
+    enum GNUNET_GenericReturnValue ret;
+
+    ret = ext->policy_post_handler (root,
+                                    &args[1],
+                                    policy_details,
+                                    policy_details_count,
+                                    &output);
+
+    if (GNUNET_OK != ret)
+    {
+      TALER_MHD_reply_json_steal (
+        rc->connection,
+        output,
+        MHD_HTTP_BAD_REQUEST);
+    }
+
+    /* execute fulfillment transaction */
+    {
+      MHD_RESULT mhd_ret;
+      struct TALER_PolicyFulfillmentTransactionData fulfillment = {
+        .proof = root,
+        .timestamp = GNUNET_TIME_timestamp_get (),
+        .details = policy_details,
+	.details_count = policy_details_count
+      };
+
+      if (GNUNET_OK !=
+          TEH_DB_run_transaction (rc->connection,
+                                  "execute policy fulfillment",
+                                  TEH_MT_REQUEST_POLICY_FULFILMENT,
+                                  &mhd_ret,
+                                  &policy_fulfillment_transaction,
+                                  &fulfillment))
+      {
+        json_decref (output);
+        return mhd_ret;
+      }
+    }
+  }
+
+  return TALER_MHD_reply_json_steal (rc->connection,
+                                     output,
+                                     MHD_HTTP_OK);
+}
+
+
 /* end of taler-exchange-httpd_extensions.c */
diff --git a/src/exchange/taler-exchange-httpd_extensions.h b/src/exchange/taler-exchange-httpd_extensions.h
index 4659b653..e435f8f0 100644
--- a/src/exchange/taler-exchange-httpd_extensions.h
+++ b/src/exchange/taler-exchange-httpd_extensions.h
@@ -40,4 +40,19 @@ TEH_extensions_init (void);
 void
 TEH_extensions_done (void);
 
+
+/**
+ * Handle POST "/extensions/..." requests.
+ *
+ * @param rc request context
+ * @param root uploaded JSON data
+ * @param args array of additional options
+ * @return MHD result code
+ */
+MHD_RESULT
+TEH_extensions_post_handler (
+  struct TEH_RequestContext *rc,
+  const json_t *root,
+  const char *const args[]);
+
 #endif
diff --git a/src/exchange/taler-exchange-httpd_metrics.h b/src/exchange/taler-exchange-httpd_metrics.h
index c1b7326f..5acd3605 100644
--- a/src/exchange/taler-exchange-httpd_metrics.h
+++ b/src/exchange/taler-exchange-httpd_metrics.h
@@ -44,7 +44,8 @@ enum TEH_MetricTypeRequest
   TEH_MT_REQUEST_IDEMPOTENT_MELT = 10,
   TEH_MT_REQUEST_IDEMPOTENT_BATCH_WITHDRAW = 11,
   TEH_MT_REQUEST_BATCH_DEPOSIT = 12,
-  TEH_MT_REQUEST_COUNT = 13 /* MUST BE LAST! */
+  TEH_MT_REQUEST_POLICY_FULFILMENT = 13,
+  TEH_MT_REQUEST_COUNT = 14 /* MUST BE LAST! */
 };
 
 /**