simplify DB logic in auditor-httpd

5 files changed, 68 insertions, 377 deletions

diff --git a/src/auditor/Makefile.am b/src/auditor/Makefile.am
index 322e61799..e129fb46a 100644
--- a/src/auditor/Makefile.am
+++ b/src/auditor/Makefile.am
@@ -49,7 +49,6 @@ taler_auditor_LDADD = \
 
 taler_auditor_httpd_SOURCES = \
   taler-auditor-httpd.c taler-auditor-httpd.h \
-  taler-auditor-httpd_db.c taler-auditor-httpd_db.h \
   taler-auditor-httpd_deposit-confirmation.c taler-auditor-httpd_deposit-confirmation.h \
   taler-auditor-httpd_exchanges.c taler-auditor-httpd_exchanges.h \
   taler-auditor-httpd_mhd.c taler-auditor-httpd_mhd.h
diff --git a/src/auditor/taler-auditor-httpd_db.c b/src/auditor/taler-auditor-httpd_db.c
deleted file mode 100644
index ba40ff808..000000000
--- a/src/auditor/taler-auditor-httpd_db.c
+++ /dev/null
@@ -1,129 +0,0 @@
-/*
-  This file is part of TALER
-  Copyright (C) 2014-2018 GNUnet e.V.
-
-  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 taler-auditor-httpd_db.c
- * @brief Generic database operations for the auditor.
- * @author Christian Grothoff
- */
-#include "platform.h"
-#include <pthread.h>
-#include <jansson.h>
-#include <gnunet/gnunet_json_lib.h>
-#include "taler_json_lib.h"
-#include "taler_mhd_lib.h"
-#include "taler-auditor-httpd_db.h"
-#include "taler-auditor-httpd.h"
-
-
-/**
- * How often should we retry a transaction before giving up
- * (for transactions resulting in serialization/dead locks only).
- */
-#define MAX_TRANSACTION_COMMIT_RETRIES 100
-
-
-/**
- * Run a database transaction for @a connection.
- * Starts a transaction and calls @a cb.  Upon success,
- * attempts to commit the transaction.  Upon soft failures,
- * retries @a cb a few times.  Upon hard or persistent soft
- * errors, generates an error message for @a connection.
- *
- * @param connection MHD connection to run @a cb for
- * @param name name of the transaction (for debugging)
- * @param[out] set to MHD response code, if transaction failed
- * @param cb callback implementing transaction logic
- * @param cb_cls closure for @a cb, must be read-only!
- * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
- */
-int
-TAH_DB_run_transaction (struct MHD_Connection *connection,
-                        const char *name,
-                        int *mhd_ret,
-                        TAH_DB_TransactionCallback cb,
-                        void *cb_cls)
-{
-  struct TALER_AUDITORDB_Session *session;
-
-  if (NULL != mhd_ret)
-    *mhd_ret = -1; /* invalid value */
-  if (NULL == (session = TAH_plugin->get_session (TAH_plugin->cls)))
-  {
-    GNUNET_break (0);
-    if (NULL != mhd_ret)
-      *mhd_ret = TALER_MHD_reply_with_error (connection,
-                                             MHD_HTTP_INTERNAL_SERVER_ERROR,
-                                             TALER_EC_DB_SETUP_FAILED,
-                                             "failed to establish session with database");
-    return GNUNET_SYSERR;
-  }
-  for (unsigned int retries = 0; retries < MAX_TRANSACTION_COMMIT_RETRIES;
-       retries++)
-  {
-    enum GNUNET_DB_QueryStatus qs;
-
-    if (GNUNET_OK !=
-        TAH_plugin->start (TAH_plugin->cls,
-                           session))
-    {
-      GNUNET_break (0);
-      if (NULL != mhd_ret)
-        *mhd_ret = TALER_MHD_reply_with_error (connection,
-                                               MHD_HTTP_INTERNAL_SERVER_ERROR,
-                                               TALER_EC_DB_START_FAILED,
-                                               "failed to begin transaction");
-      return GNUNET_SYSERR;
-    }
-    qs = cb (cb_cls,
-             connection,
-             session,
-             mhd_ret);
-    if (0 > qs)
-      TAH_plugin->rollback (TAH_plugin->cls,
-                            session);
-    if (GNUNET_DB_STATUS_HARD_ERROR == qs)
-      return GNUNET_SYSERR;
-    if (0 <= qs)
-      qs = TAH_plugin->commit (TAH_plugin->cls,
-                               session);
-    if (GNUNET_DB_STATUS_HARD_ERROR == qs)
-    {
-      if (NULL != mhd_ret)
-        *mhd_ret = TALER_MHD_reply_with_error (connection,
-                                               MHD_HTTP_INTERNAL_SERVER_ERROR,
-                                               TALER_EC_DB_COMMIT_FAILED_HARD,
-                                               "failed to commit transaction");
-      return GNUNET_SYSERR;
-    }
-    /* make sure callback did not violate invariants! */
-    GNUNET_assert ( (NULL == mhd_ret) ||
-                    (-1 == *mhd_ret) );
-    if (0 <= qs)
-      return GNUNET_OK;
-  }
-  TALER_LOG_ERROR ("Transaction `%s' commit failed %u times\n",
-                   name,
-                   MAX_TRANSACTION_COMMIT_RETRIES);
-  if (NULL != mhd_ret)
-    *mhd_ret = TALER_MHD_reply_with_error (connection,
-                                           MHD_HTTP_INTERNAL_SERVER_ERROR,
-                                           TALER_EC_DB_COMMIT_FAILED_ON_RETRY,
-                                           "transaction repeatedly failed to serialize");
-  return GNUNET_SYSERR;
-}
-
-
-/* end of taler-auditor-httpd_db.c */
diff --git a/src/auditor/taler-auditor-httpd_db.h b/src/auditor/taler-auditor-httpd_db.h
deleted file mode 100644
index 1f702c818..000000000
--- a/src/auditor/taler-auditor-httpd_db.h
+++ /dev/null
@@ -1,72 +0,0 @@
-/*
-  This file is part of TALER
-  Copyright (C) 2014-2018 GNUnet e.V.
-
-  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 auditor/taler-auditor-httpd_db.h
- * @brief High-level (transactional-layer) database operations for the auditor
- * @author Chrisitan Grothoff
- */
-#ifndef TALER_AUDITOR_HTTPD_DB_H
-#define TALER_AUDITOR_HTTPD_DB_H
-
-#include <microhttpd.h>
-#include "taler_auditordb_plugin.h"
-
-/**
- * Function implementing a database transaction.  Runs the transaction
- * logic; IF it returns a non-error code, the transaction logic MUST
- * NOT queue a MHD response.  IF it returns an hard error, the
- * transaction logic MUST queue a MHD response and set @a mhd_ret.  IF
- * it returns the soft error code, the function MAY be called again to
- * retry and MUST not queue a MHD response.
- *
- * @param cls closure
- * @param connection MHD request which triggered the transaction
- * @param session database session to use
- * @param[out] mhd_ret set to MHD response status for @a connection,
- *             if transaction failed (!)
- * @return transaction status
- */
-typedef enum GNUNET_DB_QueryStatus
-(*TAH_DB_TransactionCallback)(void *cls,
-                              struct MHD_Connection *connection,
-                              struct TALER_AUDITORDB_Session *session,
-                              int *mhd_ret);
-
-
-/**
- * Run a database transaction for @a connection.
- * Starts a transaction and calls @a cb.  Upon success,
- * attempts to commit the transaction.  Upon soft failures,
- * retries @a cb a few times.  Upon hard or persistent soft
- * errors, generates an error message for @a connection.
- *
- * @param connection MHD connection to run @a cb for
- * @param name name of the transaction (for debugging)
- * @param[out] set to MHD response code, if transaction failed
- * @param cb callback implementing transaction logic
- * @param cb_cls closure for @a cb, must be read-only!
- * @return #GNUNET_OK on success, #GNUNET_SYSERR on failure
- */
-int
-TAH_DB_run_transaction (struct MHD_Connection *connection,
-                        const char *name,
-                        int *mhd_ret,
-                        TAH_DB_TransactionCallback cb,
-                        void *cb_cls);
-
-
-#endif
-/* TALER_AUDITOR_HTTPD_DB_H */
diff --git a/src/auditor/taler-auditor-httpd_deposit-confirmation.c b/src/auditor/taler-auditor-httpd_deposit-confirmation.c
index 0a121fdae..5b5aa8eb0 100644
--- a/src/auditor/taler-auditor-httpd_deposit-confirmation.c
+++ b/src/auditor/taler-auditor-httpd_deposit-confirmation.c
@@ -1,6 +1,6 @@
 /*
   This file is part of TALER
-  Copyright (C) 2014-2018 Inria and GNUnet e.V.
+  Copyright (C) 2014-2020 Taler Systems SA
 
   TALER is free software; you can redistribute it and/or modify it under the
   terms of the GNU Affero General Public License as published by the Free Software
@@ -29,99 +29,10 @@
 #include "taler_json_lib.h"
 #include "taler_mhd_lib.h"
 #include "taler-auditor-httpd.h"
-#include "taler-auditor-httpd_db.h"
 #include "taler-auditor-httpd_deposit-confirmation.h"
 
 
 /**
- * Send confirmation of deposit-confirmation success to client.
- *
- * @param connection connection to the client
- * @return MHD result code
- */
-static int
-reply_deposit_confirmation_success (struct MHD_Connection *connection)
-{
-  return TALER_MHD_reply_json_pack (connection,
-                                    MHD_HTTP_OK,
-                                    "{s:s}",
-                                    "status", "DEPOSIT_CONFIRMATION_OK");
-}
-
-
-/**
- * Store exchange's signing key information in the database.
- *
- * @param cls a `struct TALER_AUDITORDB_ExchangeSigningKey *`
- * @param connection MHD request context
- * @param session database session and transaction to use
- * @param[out] mhd_ret set to MHD status on error
- * @return transaction status
- */
-static enum GNUNET_DB_QueryStatus
-store_exchange_signing_key_transaction (void *cls,
-                                        struct MHD_Connection *connection,
-                                        struct TALER_AUDITORDB_Session *session,
-                                        int *mhd_ret)
-{
-  const struct TALER_AUDITORDB_ExchangeSigningKey *es = cls;
-  enum GNUNET_DB_QueryStatus qs;
-
-  qs = TAH_plugin->insert_exchange_signkey (TAH_plugin->cls,
-                                            session,
-                                            es);
-  if (GNUNET_DB_STATUS_HARD_ERROR == qs)
-  {
-    TALER_LOG_WARNING ("Failed to store exchange signing key in database\n");
-    *mhd_ret = TALER_MHD_reply_with_error (connection,
-                                           MHD_HTTP_INTERNAL_SERVER_ERROR,
-                                           TALER_EC_AUDITOR_EXCHANGE_STORE_DB_ERROR,
-                                           "failed to persist exchange signing key");
-  }
-  return qs;
-}
-
-
-/**
- * Execute database transaction for /deposit-confirmation.  Runs the
- * transaction logic; IF it returns a non-error code, the transaction
- * logic MUST NOT queue a MHD response.  IF it returns an hard error,
- * the transaction logic MUST queue a MHD response and set @a mhd_ret.
- * IF it returns the soft error code, the function MAY be called again
- * to retry and MUST not queue a MHD response.
- *
- * @param cls a `struct DepositConfirmation *`
- * @param connection MHD request context
- * @param session database session and transaction to use -- FIXME: needed?
- * @param[out] mhd_ret set to MHD status on error
- * @return transaction status
- */
-static enum GNUNET_DB_QueryStatus
-deposit_confirmation_transaction (void *cls,
-                                  struct MHD_Connection *connection,
-                                  struct TALER_AUDITORDB_Session *session,
-                                  int *mhd_ret)
-{
-  const struct TALER_AUDITORDB_DepositConfirmation *dc = cls;
-  enum GNUNET_DB_QueryStatus qs;
-
-  qs = TAH_plugin->insert_deposit_confirmation (TAH_plugin->cls,
-                                                session,
-                                                dc);
-  if (GNUNET_DB_STATUS_HARD_ERROR == qs)
-  {
-    TALER_LOG_WARNING (
-      "Failed to store /deposit-confirmation information in database\n");
-    *mhd_ret = TALER_MHD_reply_with_error (connection,
-                                           MHD_HTTP_INTERNAL_SERVER_ERROR,
-                                           TALER_EC_DEPOSIT_CONFIRMATION_STORE_DB_ERROR,
-                                           "failed to persist deposit-confirmation data");
-  }
-  return qs;
-}
-
-
-/**
  * We have parsed the JSON information about the deposit, do some
  * basic sanity checks (especially that the signature on the coin is
  * valid, and that this type of coin exists) and then execute the
@@ -141,7 +52,8 @@ verify_and_execute_deposit_confirmation (struct MHD_Connection *connection,
 {
   struct TALER_ExchangeSigningKeyValidityPS skv;
   struct TALER_DepositConfirmationPS dcs;
-  int mhd_ret;
+  struct TALER_AUDITORDB_Session *session;
+  enum GNUNET_DB_QueryStatus qs;
 
   /* check exchange signing key signature */
   skv.purpose.purpose = htonl (TALER_SIGNATURE_MASTER_SIGNING_KEY_VALIDITY);
@@ -164,14 +76,27 @@ verify_and_execute_deposit_confirmation (struct MHD_Connection *connection,
                                        "master_sig");
   }
 
+  session = TAH_plugin->get_session (TAH_plugin->cls);
+  if (NULL == session)
+  {
+    GNUNET_break (0);
+    return TALER_MHD_reply_with_error (connection,
+                                       MHD_HTTP_INTERNAL_SERVER_ERROR,
+                                       TALER_EC_DB_SETUP_FAILED,
+                                       "failed to establish session with database");
+  }
   /* execute transaction */
-  if (GNUNET_OK !=
-      TAH_DB_run_transaction (connection,
-                              "persist exchange signing key",
-                              &mhd_ret,
-                              &store_exchange_signing_key_transaction,
-                              (void *) es))
-    return mhd_ret;
+  qs = TAH_plugin->insert_exchange_signkey (TAH_plugin->cls,
+                                            session,
+                                            es);
+  if (GNUNET_DB_STATUS_HARD_ERROR == qs)
+  {
+    TALER_LOG_WARNING ("Failed to store exchange signing key in database\n");
+    return TALER_MHD_reply_with_error (connection,
+                                       MHD_HTTP_INTERNAL_SERVER_ERROR,
+                                       TALER_EC_AUDITOR_EXCHANGE_STORE_DB_ERROR,
+                                       "failed to persist exchange signing key");
+  }
 
   /* check deposit confirmation signature */
   dcs.purpose.purpose = htonl (TALER_SIGNATURE_EXCHANGE_CONFIRM_DEPOSIT);
@@ -198,14 +123,21 @@ verify_and_execute_deposit_confirmation (struct MHD_Connection *connection,
   }
 
   /* execute transaction */
-  if (GNUNET_OK !=
-      TAH_DB_run_transaction (connection,
-                              "store deposit confirmation",
-                              &mhd_ret,
-                              &deposit_confirmation_transaction,
-                              (void *) dc))
-    return mhd_ret;
-  return reply_deposit_confirmation_success (connection);
+  qs = TAH_plugin->insert_deposit_confirmation (TAH_plugin->cls,
+                                                session,
+                                                dc);
+  if (GNUNET_DB_STATUS_HARD_ERROR == qs)
+  {
+    TALER_LOG_WARNING ("Failed to store /deposit-confirmation in database\n");
+    return TALER_MHD_reply_with_error (connection,
+                                       MHD_HTTP_INTERNAL_SERVER_ERROR,
+                                       TALER_EC_DEPOSIT_CONFIRMATION_STORE_DB_ERROR,
+                                       "failed to persist deposit-confirmation data");
+  }
+  return TALER_MHD_reply_json_pack (connection,
+                                    MHD_HTTP_OK,
+                                    "{s:s}",
+                                    "status", "DEPOSIT_CONFIRMATION_OK");
 }
 
 
diff --git a/src/auditor/taler-auditor-httpd_exchanges.c b/src/auditor/taler-auditor-httpd_exchanges.c
index 3c6bfe68f..e5442a051 100644
--- a/src/auditor/taler-auditor-httpd_exchanges.c
+++ b/src/auditor/taler-auditor-httpd_exchanges.c
@@ -1,6 +1,6 @@
 /*
   This file is part of TALER
-  Copyright (C) 2014-2018 Inria and GNUnet e.V.
+  Copyright (C) 2014-2020 Taler Systems SA
 
   TALER is free software; you can redistribute it and/or modify it under the
   terms of the GNU Affero General Public License as published by the Free Software
@@ -27,29 +27,10 @@
 #include "taler_json_lib.h"
 #include "taler_mhd_lib.h"
 #include "taler-auditor-httpd.h"
-#include "taler-auditor-httpd_db.h"
 #include "taler-auditor-httpd_exchanges.h"
 
 
 /**
- * Send confirmation of deposit-confirmation success to client.
- *
- * @param connection connection to the client
- * @param ja array with information about exchanges
- * @return MHD result code
- */
-static int
-reply_exchanges_success (struct MHD_Connection *connection,
-                         json_t *ja)
-{
-  return TALER_MHD_reply_json_pack (connection,
-                                    MHD_HTTP_OK,
-                                    "{s:o}",
-                                    "exchanges", ja);
-}
-
-
-/**
  * Add exchange information to the list.
  *
  * @param[in,out] cls a `json_t *` array to extend
@@ -78,45 +59,6 @@ add_exchange (void *cls,
 
 
 /**
- * Execute database transaction for /exchanges. Obtains the list.  IF
- * it returns a non-error code, the transaction logic MUST NOT queue a
- * MHD response.  IF it returns an hard error, the transaction logic
- * MUST queue a MHD response and set @a mhd_ret.  IF it returns the
- * soft error code, the function MAY be called again to retry and MUST
- * not queue a MHD response.
- *
- * @param cls[in,out] a `json_t *` with an array of exchanges to be created
- * @param connection MHD request context
- * @param session database session and transaction to use
- * @param[out] mhd_ret set to MHD status on error
- * @return transaction status
- */
-static enum GNUNET_DB_QueryStatus
-list_exchanges (void *cls,
-                struct MHD_Connection *connection,
-                struct TALER_AUDITORDB_Session *session,
-                int *mhd_ret)
-{
-  json_t *list = cls;
-  enum GNUNET_DB_QueryStatus qs;
-
-  qs = TAH_plugin->list_exchanges (TAH_plugin->cls,
-                                   session,
-                                   &add_exchange,
-                                   list);
-  if (GNUNET_DB_STATUS_HARD_ERROR == qs)
-  {
-    TALER_LOG_WARNING ("Failed to handle /exchanges in database\n");
-    *mhd_ret = TALER_MHD_reply_with_error (connection,
-                                           MHD_HTTP_INTERNAL_SERVER_ERROR,
-                                           TALER_EC_LIST_EXCHANGES_DB_ERROR,
-                                           "Could not fetch exchange list from database");
-  }
-  return qs;
-}
-
-
-/**
  * Handle a "/exchanges" request.
  *
  * @param rh context of the handler
@@ -133,19 +75,38 @@ TAH_EXCHANGES_handler (struct TAH_RequestHandler *rh,
                        const char *upload_data,
                        size_t *upload_data_size)
 {
-  int mhd_ret;
   json_t *ja;
+  struct TALER_AUDITORDB_Session *session;
+  enum GNUNET_DB_QueryStatus qs;
 
+  session = TAH_plugin->get_session (TAH_plugin->cls);
+  if (NULL == session)
+  {
+    GNUNET_break (0);
+    return TALER_MHD_reply_with_error (connection,
+                                       MHD_HTTP_INTERNAL_SERVER_ERROR,
+                                       TALER_EC_DB_SETUP_FAILED,
+                                       "failed to establish session with database");
+  }
   ja = json_array ();
-  if (GNUNET_OK !=
-      TAH_DB_run_transaction (connection,
-                              "list exchanges",
-                              &mhd_ret,
-                              &list_exchanges,
-                              (void *) ja))
-    return mhd_ret;
-  return reply_exchanges_success (connection,
-                                  ja);
+  qs = TAH_plugin->list_exchanges (TAH_plugin->cls,
+                                   session,
+                                   &add_exchange,
+                                   ja);
+  if (0 > qs)
+  {
+    GNUNET_break (GNUNET_DB_STATUS_HARD_ERROR == qs);
+    json_decref (ja);
+    TALER_LOG_WARNING ("Failed to handle /exchanges in database\n");
+    return TALER_MHD_reply_with_error (connection,
+                                       MHD_HTTP_INTERNAL_SERVER_ERROR,
+                                       TALER_EC_LIST_EXCHANGES_DB_ERROR,
+                                       "Could not fetch exchange list from database");
+  }
+  return TALER_MHD_reply_json_pack (connection,
+                                    MHD_HTTP_OK,
+                                    "{s:o}",
+                                    "exchanges", ja);
 }