Avoid unneeded watch transactions

Store tx id for watch smart contract call while it is pending to avoid
sending unneeded transactions.

resources/migrations/20171218190701-watch-tx-id.up.sql

@@ -0,0 +1,2 @@
+ALTER TABLE "public"."issues"
+  ADD COLUMN "watch_hash" character varying(128);

resources/sql/queries.sql

@@ -339,6 +339,21 @@ UPDATE issues
 SET winner_login = :winner_login
 WHERE issue_id = :issue_id;
 
+-- :name update-watch-hash :! :n
+-- :doc updates issue with watch transaction hash
+UPDATE issues
+SET watch_hash = :watch_hash
+WHERE issue_id = :issue_id;
+
+-- :name pending-watch-calls :? :*
+-- :doc issues with a pending watch transaction
+SELECT
+issue_id,
+watch_hash
+FROM issues
+WHERE watch_hash IS NOT NULL;
+
+
 -- :name update-payout-hash :! :n
 -- :doc updates issue with payout transaction hash
 UPDATE issues
@@ -492,7 +507,8 @@ SELECT
   i.issue_id         AS issue_id,
   i.balance_eth      AS balance_eth,
   i.tokens           AS tokens,
-  i.value_usd        AS value_usd
+  i.value_usd        AS value_usd,
+  i.watch_hash       AS watch_hash
 FROM issues i, repositories r
 WHERE r.repo_id = i.repo_id
 AND contract_address IS NOT NULL

src/clj/commiteth/db/bounties.clj

@@ -55,6 +55,16 @@
   (jdbc/with-db-connection [con-db *db*]
     (db/update-winner-login con-db {:issue_id issue-id :winner_login login})))
 
+(defn update-watch-hash
+  [issue-id watch-hash]
+  (jdbc/with-db-connection [con-db *db*]
+    (db/update-watch-hash con-db {:issue_id issue-id :watch_hash watch-hash})))
+
+(defn pending-watch-calls
+  []
+  (jdbc/with-db-connection [con-db *db*]
+    (db/pending-watch-calls con-db)))
+
 (defn update-payout-hash
   [issue-id payout-hash]
   (jdbc/with-db-connection [con-db *db*]

src/clj/commiteth/scheduler.clj

@@ -129,6 +129,16 @@
         (db-bounties/update-confirm-hash issue-id confirm-hash)))))
 
 
+(defn update-watch-hash
+  "Sets watch-hash to NULL for bounties where watch tx has been mined. Used to avoid unneeded watch transactions in update-bounty-token-balances"
+  []
+  (doseq [{issue-id :issue_id
+           watch-hash :watch_hash} (db-bounties/pending-watch-calls)]
+    (log/info "pending watch call" watch-hash)
+    (when-let [receipt (eth/get-transaction-receipt watch-hash)]
+      (db-bounties/update-watch-hash issue-id nil))))
+
+
 (defn older-than-3h?
   [timestamp]
   (let [now (t/now)
@@ -198,23 +208,27 @@
 
 (defn update-bounty-token-balances
   "Helper function for updating internal ERC20 token balances to token multisig contract. Will be called periodically for all open bounty contracts."
-  [bounty-addr]
+  [issue-id bounty-addr watch-hash]
   (doseq [[tla token-data] (token-data/as-map)]
     (let [balance (multisig/token-balance bounty-addr tla)]
       (when (> balance 0)
         (do
           (log/debug "bounty at" bounty-addr "has" balance "of token" tla)
           (let [internal-balance (multisig/token-balance-in-bounty bounty-addr tla)]
-            (when (not= balance internal-balance)
+            (when (and (nil? watch-hash)
+                       (not= balance internal-balance))
               (log/info "balances not in sync, calling watch")
-              (multisig/watch-token bounty-addr tla))))))))
+              (let [hash (multisig/watch-token bounty-addr tla)]
+                (db-bounties/update-watch-hash issue-id hash)))))))))
 
 (defn update-contract-internal-balances
   "It is required in our current smart contract to manually update it's internal balance when some tokens have been added."
   []
-  (doseq [{bounty-address :contract_address}
+  (doseq [{issue-id :issue_id
+           bounty-address :contract_address
+           watch-hash :watch_hash}
           (db-bounties/open-bounty-contracts)]
-    (update-bounty-token-balances bounty-address)))
+    (update-bounty-token-balances issue-id bounty-address watch-hash)))
 
 
 (defn get-bounty-funds
@@ -313,6 +327,7 @@
       update-issue-contract-address
       update-confirm-hash
       update-payout-receipt
+      update-watch-hash
       self-sign-bounty
       update-contract-internal-balances
       update-balances])