Update GetBlockchainInfoResult to support Vec of warnings

Author: jfldde

json/src/lib.rs

@@ -1080,6 +1080,14 @@ pub struct GetAddressInfoResult {
     pub label: Option<String>,
 }
 
+/// Used to represent values that can either be a string or a string array.
+#[derive(Clone, Debug, Deserialize, PartialEq, Eq, Serialize)]
+#[serde(untagged)]
+pub enum StringOrStringArray {
+    String(String),
+    StringArray(Vec<String>),
+}
+
 /// Models the result of "getblockchaininfo"
 #[derive(Clone, Debug, Deserialize, Serialize)]
 pub struct GetBlockchainInfoResult {
@@ -1121,8 +1129,8 @@ pub struct GetBlockchainInfoResult {
     /// Status of softforks in progress
     #[serde(default)]
     pub softforks: HashMap<String, Softfork>,
-    /// Any network and blockchain warnings.
-    pub warnings: String,
+    /// Any network and blockchain warnings. In later versions of bitcoind, it's an array of strings.
+    pub warnings: StringOrStringArray,
 }
 
 #[derive(Clone, PartialEq, Eq, Debug)]