simplify DB access: do not fetch fields we do not need

src/exchange/taler-exchange-aggregator.c

@@ -507,44 +507,24 @@ deposit_cb (void *cls,
  *
  * @param cls a `struct AggregationUnit`
  * @param row_id identifies database entry
- * @param exchange_timestamp when did the exchange receive the deposit
- * @param wallet_timestamp when did the wallet sign the contract
- * @param merchant_pub public key of the merchant
  * @param coin_pub public key of the coin
  * @param amount_with_fee amount that was deposited including fee
  * @param deposit_fee amount the exchange gets to keep as transaction fees
  * @param h_contract_terms hash of the proposal data known to merchant and customer
- * @param wire_deadline by which the merchant advised that he would like the
- *        wire transfer to be executed
- * @param wire wire details for the merchant
  * @return transaction status code
  */
 static enum GNUNET_DB_QueryStatus
 aggregate_cb (void *cls,
               uint64_t row_id,
-              struct GNUNET_TIME_Absolute exchange_timestamp,
-              struct GNUNET_TIME_Absolute wallet_timestamp,
-              const struct TALER_MerchantPublicKeyP *merchant_pub,
               const struct TALER_CoinSpendPublicKeyP *coin_pub,
               const struct TALER_Amount *amount_with_fee,
               const struct TALER_Amount *deposit_fee,
-              const struct GNUNET_HashCode *h_contract_terms,
+              const struct GNUNET_HashCode *h_contract_terms)
-              struct GNUNET_TIME_Absolute wire_deadline,
-              const json_t *wire)
 {
   struct AggregationUnit *au = cls;
   struct TALER_Amount old;
   enum GNUNET_DB_QueryStatus qs;
 
-  /* NOTE: potential optimization: use custom SQL API to not
-     fetch these: */
-  (void) wire_deadline; /* checked by SQL */
-  (void) exchange_timestamp;
-  (void) wallet_timestamp;
-  (void) wire; /* must match */
-  GNUNET_break (0 == GNUNET_memcmp (&au->merchant_pub,
-                                    merchant_pub));
-
   if (au->rows_offset >= TALER_EXCHANGEDB_MATCHING_DEPOSITS_LIMIT)
   {
     /* Bug: we asked for at most #TALER_EXCHANGEDB_MATCHING_DEPOSITS_LIMIT results! */

src/exchangedb/plugin_exchangedb_postgres.c

@@ -908,9 +908,6 @@ postgres_get_session (void *cls)
                               ",amount_with_fee_frac"
                               ",denom.fee_deposit_val"
                               ",denom.fee_deposit_frac"
-                              ",wire_deadline"
-                              ",exchange_timestamp"
-                              ",wallet_timestamp"
                               ",h_contract_terms"
                               ",coin_pub"
                               " FROM deposits"
@@ -2868,7 +2865,7 @@ struct MatchingDepositContext
   /**
    * Function to call for each result
    */
-  TALER_EXCHANGEDB_DepositIterator deposit_cb;
+  TALER_EXCHANGEDB_MatchingDepositIterator deposit_cb;
 
   /**
    * Closure for @e deposit_cb.
@@ -2929,9 +2926,6 @@ match_deposit_cb (void *cls,
   {
     struct TALER_Amount amount_with_fee;
     struct TALER_Amount deposit_fee;
-    struct GNUNET_TIME_Absolute exchange_timestamp;
-    struct GNUNET_TIME_Absolute wallet_timestamp;
-    struct GNUNET_TIME_Absolute wire_deadline;
     struct GNUNET_HashCode h_contract_terms;
     struct TALER_CoinSpendPublicKeyP coin_pub;
     uint64_t serial_id;
@@ -2943,12 +2937,6 @@ match_deposit_cb (void *cls,
                                    &amount_with_fee),
       TALER_PQ_RESULT_SPEC_AMOUNT ("fee_deposit",
                                    &deposit_fee),
-      TALER_PQ_result_spec_absolute_time ("wire_deadline",
-                                          &wire_deadline),
-      TALER_PQ_result_spec_absolute_time ("exchange_timestamp",
-                                          &exchange_timestamp),
-      TALER_PQ_result_spec_absolute_time ("wallet_timestamp",
-                                          &wallet_timestamp),
       GNUNET_PQ_result_spec_auto_from_type ("h_contract_terms",
                                             &h_contract_terms),
       GNUNET_PQ_result_spec_auto_from_type ("coin_pub",
@@ -2967,15 +2955,10 @@ match_deposit_cb (void *cls,
     }
     qs = mdc->deposit_cb (mdc->deposit_cb_cls,
                           serial_id,
-                          exchange_timestamp,
-                          wallet_timestamp,
-                          mdc->merchant_pub,
                           &coin_pub,
                           &amount_with_fee,
                           &deposit_fee,
-                          &h_contract_terms,
+                          &h_contract_terms);
-                          wire_deadline,
-                          NULL);
     GNUNET_PQ_cleanup_result (rs);
     if (GNUNET_DB_STATUS_SUCCESS_ONE_RESULT != qs)
       break;
@@ -3003,7 +2986,7 @@ postgres_iterate_matching_deposits (
   struct TALER_EXCHANGEDB_Session *session,
   const struct GNUNET_HashCode *h_wire,
   const struct TALER_MerchantPublicKeyP *merchant_pub,
-  TALER_EXCHANGEDB_DepositIterator deposit_cb,
+  TALER_EXCHANGEDB_MatchingDepositIterator deposit_cb,
   void *deposit_cb_cls,
   uint32_t limit)
 {

src/exchangedb/test_exchangedb.c

@@ -842,7 +842,7 @@ static uint64_t deposit_rowid;
  * @param h_contract_terms hash of the proposal data known to merchant and customer
  * @param wire_deadline by which the merchant advised that he would like the
  *        wire transfer to be executed
- * @param wire wire details for the merchant, NULL from iterate_matching_deposits()
+ * @param wire wire details for the merchant
  * @return transaction status code, #GNUNET_DB_STATUS_SUCCESS_ONE_RESULT to continue to iterate
  */
 static enum GNUNET_DB_QueryStatus
@@ -862,10 +862,9 @@ deposit_cb (void *cls,
   struct GNUNET_HashCode h_wire;
 
   deposit_rowid = rowid;
-  if (NULL != wire)
+  GNUNET_assert (GNUNET_OK ==
-    GNUNET_assert (GNUNET_OK ==
+                 TALER_JSON_merchant_wire_signature_hash (wire,
-                   TALER_JSON_merchant_wire_signature_hash (wire,
+                                                          &h_wire));
-                                                            &h_wire));
   if ( (0 != GNUNET_memcmp (merchant_pub,
                             &deposit->merchant_pub)) ||
        (0 != TALER_amount_cmp (amount_with_fee,
@@ -877,9 +876,51 @@ deposit_cb (void *cls,
        (0 != memcmp (coin_pub,
                      &deposit->coin.coin_pub,
                      sizeof (struct TALER_CoinSpendPublicKeyP))) ||
-       ( (NULL != wire) &&
+       (0 != GNUNET_memcmp (&h_wire,
-         (0 != GNUNET_memcmp (&h_wire,
+                            &deposit->h_wire)) )
-                              &deposit->h_wire)) ) )
+  {
+    GNUNET_break (0);
+    return GNUNET_DB_STATUS_HARD_ERROR;
+  }
+
+  return GNUNET_DB_STATUS_SUCCESS_ONE_RESULT;
+}
+
+
+/**
+ * Function called with details about deposits that
+ * have been made.  Called in the test on the
+ * deposit given in @a cls.
+ *
+ * @param cls closure a `struct TALER_EXCHANGEDB_Deposit *`
+ * @param rowid unique ID for the deposit in our DB, used for marking
+ *              it as 'tiny' or 'done'
+ * @param coin_pub public key of the coin
+ * @param amount_with_fee amount that was deposited including fee
+ * @param deposit_fee amount the exchange gets to keep as transaction fees
+ * @param h_contract_terms hash of the proposal data known to merchant and customer
+ * @return transaction status code, #GNUNET_DB_STATUS_SUCCESS_ONE_RESULT to continue to iterate
+ */
+static enum GNUNET_DB_QueryStatus
+matching_deposit_cb (void *cls,
+                     uint64_t rowid,
+                     const struct TALER_CoinSpendPublicKeyP *coin_pub,
+                     const struct TALER_Amount *amount_with_fee,
+                     const struct TALER_Amount *deposit_fee,
+                     const struct GNUNET_HashCode *h_contract_terms)
+{
+  struct TALER_EXCHANGEDB_Deposit *deposit = cls;
+
+  deposit_rowid = rowid;
+  if ( (0 != TALER_amount_cmp (amount_with_fee,
+                               &deposit->amount_with_fee)) ||
+       (0 != TALER_amount_cmp (deposit_fee,
+                               &deposit->deposit_fee)) ||
+       (0 != GNUNET_memcmp (h_contract_terms,
+                            &deposit->h_contract_terms)) ||
+       (0 != memcmp (coin_pub,
+                     &deposit->coin.coin_pub,
+                     sizeof (struct TALER_CoinSpendPublicKeyP))) )
   {
     GNUNET_break (0);
     return GNUNET_DB_STATUS_HARD_ERROR;
@@ -1936,7 +1977,7 @@ run (void *cls)
                                              session,
                                              &deposit.h_wire,
                                              &deposit.merchant_pub,
-                                             &deposit_cb,
+                                             &matching_deposit_cb,
                                              &deposit,
                                              2));
   sleep (2); /* giv deposit time to be ready */

src/include/taler_exchangedb_plugin.h

@@ -968,6 +968,29 @@ struct TALER_EXCHANGEDB_TransactionList
 struct TALER_EXCHANGEDB_Session;
 
 
+/**
+ * Function called with details about deposits that have been made,
+ * with the goal of executing the corresponding wire transaction.
+ *
+ * @param cls closure
+ * @param rowid unique ID for the deposit in our DB, used for marking
+ *              it as 'tiny' or 'done'
+ * @param coin_pub public key of the coin
+ * @param amount_with_fee amount that was deposited including fee
+ * @param deposit_fee amount the exchange gets to keep as transaction fees
+ * @param h_contract_terms hash of the proposal data known to merchant and customer
+ * @return transaction status code, #GNUNET_DB_STATUS_SUCCESS_ONE_RESULT to continue to iterate
+ */
+typedef enum GNUNET_DB_QueryStatus
+(*TALER_EXCHANGEDB_MatchingDepositIterator)(
+  void *cls,
+  uint64_t rowid,
+  const struct TALER_CoinSpendPublicKeyP *coin_pub,
+  const struct TALER_Amount *amount_with_fee,
+  const struct TALER_Amount *deposit_fee,
+  const struct GNUNET_HashCode *h_contract_terms);
+
+
 /**
  * Function called with details about deposits that have been made,
  * with the goal of executing the corresponding wire transaction.
@@ -985,7 +1008,7 @@ struct TALER_EXCHANGEDB_Session;
  * @param wire_deadline by which the merchant advised that he would like the
  *        wire transfer to be executed
  * @param receiver_wire_account wire details for the merchant, includes
- *        'url' in payto://-format; NULL from iterate_matching_deposits()
+ *        'url' in payto://-format;
  * @return transaction status code, #GNUNET_DB_STATUS_SUCCESS_ONE_RESULT to continue to iterate
  */
 typedef enum GNUNET_DB_QueryStatus
@@ -2019,7 +2042,7 @@ struct TALER_EXCHANGEDB_Plugin
     struct TALER_EXCHANGEDB_Session *session,
     const struct GNUNET_HashCode *h_wire,
     const struct TALER_MerchantPublicKeyP *merchant_pub,
-    TALER_EXCHANGEDB_DepositIterator deposit_cb,
+    TALER_EXCHANGEDB_MatchingDepositIterator deposit_cb,
     void *deposit_cb_cls,
     uint32_t limit);