Check if a tx is already present in mempool

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GitGab19#16 (comment)

roles/jd-server/src/lib/job_declarator/message_handler.rs

@@ -62,7 +62,7 @@ impl ParseClientJobDeclarationMessages for JobDeclaratorDownstream {
 
     fn handle_declare_mining_job(&mut self, message: DeclareMiningJob) -> Result<SendTo, Error> {
         // the transactions that are present in the mempool are stored here, that is sent to the
-        // mempool which use the rpc client to retrieve the whole data for each transactions.
+        // mempool which use the rpc client to retrieve the whole data for each transaction.
         // The unknown transactions is a vector that contains the transactions that are not in the
         // jds mempool, and will be non-empty in the ProvideMissingTransactionsSuccess message
         let mut known_transactions: Vec<Txid> = vec![];

roles/jd-server/src/lib/mempool/mod.rs

@@ -75,11 +75,13 @@ impl JDsMempool {
         // fill in the mempool the transactions id in the mempool with the full transactions
         // retrieved from the jd client
         for txid in txids {
-            let transaction = client
-                .get_raw_transaction(&txid.to_string(), None)
-                .await
-                .map_err(JdsMempoolError::Rpc)?;
-            let _ = self_.safe_lock(|a| a.mempool.insert(transaction.txid(), Some(transaction)));
+            if let None = self_.safe_lock(|a| a.mempool.get(&txid).cloned()).map_err(|e| JdsMempoolError::PoisonLock(e.to_string()))? {
+                let transaction = client
+                    .get_raw_transaction(&txid.to_string(), None)
+                    .await
+                    .map_err(JdsMempoolError::Rpc)?;
+                let _ = self_.safe_lock(|a| a.mempool.insert(transaction.txid(), Some(transaction)));
+            }
         }
 
         // fill in the mempool the transactions given in input