feat: add monerod fallback strategy (#6764)

Description
---
- Added a monerod fallback strategy whereby static monerod responses can
be loaded if monerod goes offline. Options are always use monerod, use
static monerod responses when monerod goes offline, or always use static
monerod responses. With this implementation, it is possible to merge
mine offline from monerod.
- Reduced the general connection monerod timeout from 5s to 2s; this
improves overall monerod responsiveness in event of a monerod connection
error.
- Fixed a bug whereby the same monerod entry would be retried over and
over in the event of a monerod connection error.

Closes #6756

Motivation and Context
---
This could improve merge mining with Tari Universe.

How Has This Been Tested?
---
System-level testing
Added unit tests

What process can a PR reviewer use to test or verify this change?
---
Code review
System-level testing

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Breaking Changes
---

- [x] None
- [ ] Requires data directory on base node to be deleted
- [ ] Requires hard fork
- [ ] Other - Please specify

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---------

Co-authored-by: SW van Heerden <swvheerden@gmail.com>

applications/minotari_merge_mining_proxy/Cargo.toml

@@ -40,7 +40,7 @@ hyper = { version = "0.14.12", features = ["default"] }
 jsonrpc = "0.12.0"
 log = { version = "0.4.8", features = ["std"] }
 markup5ever = "0.12.1"
-monero = { version = "0.21.0" }
+monero = { version = "0.21.0" , features = ["serde"] }
 reqwest = { version = "0.11.4", features = ["json"] }
 serde = { version = "1.0.136", features = ["derive"] }
 serde_json = "1.0.57"
@@ -50,6 +50,8 @@ tonic = "0.12.3"
 tracing = "0.1"
 url = "2.1.1"
 scraper = "0.19.0"
+toml = "0.8.19"
+regex = "1.11.1"
 
 [build-dependencies]
 tari_features = { path = "../../common/tari_features", version = "1.11.1-pre.1" }

applications/minotari_merge_mining_proxy/src/block_template_protocol.rs

@@ -83,7 +83,7 @@ impl<'a> BlockTemplateProtocol<'a> {
 #[allow(clippy::too_many_lines)]
 impl BlockTemplateProtocol<'_> {
     /// Create [FinalBlockTemplateData] with [MoneroMiningData].
-    pub async fn get_next_block_template(
+    pub async fn get_next_tari_block_template(
         mut self,
         monero_mining_data: MoneroMiningData,
         block_templates: &BlockTemplateRepository,

applications/minotari_merge_mining_proxy/src/config.rs

@@ -20,12 +20,15 @@
 // WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 // USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-use std::path::{Path, PathBuf};
+use std::{
+    path::{Path, PathBuf},
+    time::Duration,
+};
 
 use minotari_wallet_grpc_client::GrpcAuthentication;
 use serde::{Deserialize, Serialize};
 use tari_common::{
-    configuration::{Network, StringList},
+    configuration::{serializers, Network, StringList},
     SubConfigPath,
 };
 use tari_common_types::tari_address::TariAddress;
@@ -94,8 +97,22 @@ pub struct MergeMiningProxyConfig {
     pub wallet_payment_address: String,
     /// Range proof type - revealed_value or bullet_proof_plus: (default = revealed_value)
     pub range_proof_type: RangeProofType,
-    /// Use p2pool to submit and get block templates
+    /// Use p2pool to submit and get block templates (default = false)
     pub p2pool_enabled: bool,
+    /// Monero fallback strategy(default = MonerodFallback::MonerodOnly)
+    pub monerod_fallback: MonerodFallback,
+    /// The timeout duration for connecting to monerod (default = 2s)
+    #[serde(with = "serializers::seconds")]
+    pub monerod_connection_timeout: Duration,
+}
+
+#[derive(Default, Debug, Clone, Copy, Serialize, Deserialize, Eq, PartialEq)]
+#[serde(rename_all = "snake_case")]
+pub(crate) enum MonerodFallback {
+    MonerodOnly,
+    #[default]
+    StaticWhenMonerodFails,
+    StaticOnly,
 }
 
 impl Default for MergeMiningProxyConfig {
@@ -157,6 +174,8 @@ impl Default for MergeMiningProxyConfig {
             wallet_payment_address: TariAddress::default().to_base58(),
             range_proof_type: RangeProofType::RevealedValue,
             p2pool_enabled: false,
+            monerod_fallback: Default::default(),
+            monerod_connection_timeout: Duration::from_secs(2),
         }
     }
 }
@@ -179,10 +198,11 @@ impl SubConfigPath for MergeMiningProxyConfig {
 mod test {
     use std::str::FromStr;
 
+    use serde::{Deserialize, Serialize};
     use tari_common::DefaultConfigLoader;
     use tari_comms::multiaddr::Multiaddr;
 
-    use crate::config::MergeMiningProxyConfig;
+    use crate::config::{MergeMiningProxyConfig, MonerodFallback};
 
     fn get_config(override_from: &str) -> config::Config {
         let s = r#"
@@ -241,4 +261,35 @@ mod test {
         assert!(!config.monerod_use_auth);
         assert!(config.submit_to_origin);
     }
+
+    #[derive(Clone, Serialize, Deserialize, Debug)]
+    #[allow(clippy::struct_excessive_bools)]
+    struct TestConfig {
+        name: String,
+        inner_config_1: TestInnerConfig,
+        inner_config_2: TestInnerConfig,
+        inner_config_3: TestInnerConfig,
+    }
+
+    #[derive(Clone, Serialize, Deserialize, Debug)]
+    #[allow(clippy::struct_excessive_bools)]
+    struct TestInnerConfig {
+        monerod: MonerodFallback,
+    }
+
+    #[test]
+    fn it_deserializes_enums() {
+        let config_str = r#"
+            name = "blockchain champion"
+            inner_config_1.monerod = "monerod_only"
+            inner_config_2.monerod = "static_when_monerod_fails"
+            inner_config_3.monerod = "static_only"
+        "#;
+        let config = toml::from_str::<TestConfig>(config_str).unwrap();
+
+        // Enums in the config
+        assert_eq!(config.inner_config_1.monerod, MonerodFallback::MonerodOnly);
+        assert_eq!(config.inner_config_2.monerod, MonerodFallback::StaticWhenMonerodFails);
+        assert_eq!(config.inner_config_3.monerod, MonerodFallback::StaticOnly);
+    }
 }