[docs] clarify when the fee could be unknown

2021-07-12 10:06:08 +02:00 · 2021-07-12 10:06:08 +02:00 · a6ce75fa2d
commit a6ce75fa2d
parent c1077b95cf
1 changed files with 4 additions and 1 deletions
--- a/src/types.rs
+++ b/src/types.rs
@ -160,7 +160,10 @@ pub struct TransactionDetails {
    pub received: u64,
    /// Sent value (sats)
    pub sent: u64,
-    /// Fee value (sats) if available
+    /// Fee value (sats) if available.
+    /// The availability of the fee depends on the backend. It's never `None` with an Electrum
+    /// Server backend, but it could be `None` with a Bitcoin RPC node without txindex that receive
+    /// funds while offline.
    pub fee: Option<u64>,
    /// If the transaction is confirmed, contains height and timestamp of the block containing the
    /// transaction, unconfirmed transaction contains `None`.