Recover from bot account ETH balance running out

Recover from situation where Commit ETH bot account's ETH balance runs out and gets replenished by re-deploying contracts that were not actually written to the blockchain.

Fixes: #58

resources/sql/queries.sql

@@ -165,7 +165,8 @@ WHERE issue_id = :issue_id;
 -- :doc retrieves pending transaction ids
 SELECT
   issue_id,
-  transaction_hash
+  transaction_hash,
+  owner_address
 FROM issues
 WHERE contract_address IS NULL
 AND issues.transaction_hash IS NOT NULL;

src/clj/commiteth/scheduler.clj

@@ -45,18 +45,33 @@
                                  balance-str))))))
 
 
+(defn deploy-contract [owner-address issue-id]
+  (let [transaction-hash (eth/deploy-contract owner-address)]
+      (if (nil? transaction-hash)
+        (log/error "Failed to deploy contract to" owner-address)
+        (log/info "Contract deployed, transaction-hash:"
+                  transaction-hash ))
+      (issues/update-transaction-hash issue-id transaction-hash)))
+
+
+(defn redeploy-failed-contracts
+  "If the bot account runs out of gas, we end up with transaction-id in db, but with nothing written to blockchain. In this case we should try to re-deploy the contract."
+  []
+  (doseq [{issue-id :issue_id
+           transaction-hash :transaction_hash
+           owner-address :owner_address} (issues/list-pending-deployments)]
+    (when (nil? (eth/get-transaction-receipt transaction-hash))
+      (log/info "Detected nil transaction receipt for pending contract deployment for issue" issue-id ", re-deploying contract")
+      (deploy-contract owner-address issue-id))))
+
+
 (defn deploy-pending-contracts
   "Under high-concurrency circumstances or in case geth is in defunct state, a bounty contract may not deploy successfully when the bounty label is addded to an issue. This function deploys such contracts."
   []
   (doseq [{issue-id :issue_id
            owner-address :owner_address} (db-bounties/pending-contracts)]
     (log/debug "Trying to re-deploy failed bounty contract deployment, issue-id:" issue-id)
-    (let [transaction-hash (eth/deploy-contract owner-address)]
-      (if (nil? transaction-hash)
-        (log/error "Failed to deploy contract to" owner-address)
-        (log/info "Contract deployed, transaction-hash:"
-                  transaction-hash ))
-      (issues/update-transaction-hash issue-id transaction-hash))))
+    (deploy-contract owner-address issue-id)))
 
 (defn self-sign-bounty
   "Walks through all issues eligible for bounty payout and signs corresponding transaction"
@@ -169,6 +184,7 @@
 (defn run-periodic-tasks [time]
   (do
     (log/debug "run-periodic-tasks" time)
+    (redeploy-failed-contracts)
     (deploy-pending-contracts)
     (update-issue-contract-address)
     (update-confirm-hash)