refactor(meta/config): Adapt RFC Config Backward Compatibility

common/meta/embedded/src/meta_embedded.rs

@@ -51,9 +51,10 @@ impl MetaEmbedded {
     /// - `common_meta_sled_store::init_sled_db`
     /// - `common_meta_sled_store::init_temp_sled_db`
     pub async fn new(name: &str) -> common_exception::Result<MetaEmbedded> {
-        let mut config = RaftConfig::empty();
-
-        config.sled_tree_prefix = format!("{}-local-kv", name);
+        let mut config = RaftConfig {
+            sled_tree_prefix: format!("{}-local-kv", name),
+            ..Default::default()
+        };
 
         if cfg!(target_os = "macos") {
             tracing::warn!("Disabled fsync for meta data tests. fsync on mac is quite slow");

common/meta/raft-store/Cargo.toml

@@ -24,7 +24,6 @@ common-tracing = { path = "../../tracing" }
 anyhow = "1.0.56"
 async-trait = "0.1.53"
 bytes = "1.1.0"
-clap = { version = "3.1.8", features = ["derive", "env"] }
 derive_more = "0.99.17"
 hostname = "0.3.1"
 maplit = "1.0.2"

common/meta/raft-store/src/config.rs

@@ -14,16 +14,13 @@
 
 use std::net::Ipv4Addr;
 
-use clap::Parser;
 use common_exception::Result;
 use common_grpc::DNSResolver;
 use common_meta_types::Endpoint;
 use common_meta_types::MetaError;
 use common_meta_types::MetaResult;
 use common_meta_types::NodeId;
 use once_cell::sync::Lazy;
-use serde::Deserialize;
-use serde::Serialize;
 
 pub static DATABEND_COMMIT_VERSION: Lazy<String> = Lazy::new(|| {
     let build_semver = option_env!("VERGEN_BUILD_SEMVER");
@@ -43,97 +40,63 @@ pub static DATABEND_COMMIT_VERSION: Lazy<String> = Lazy::new(|| {
     ver
 });
 
-pub const KVSRV_LISTEN_HOST: &str = "KVSRV_LISTEN_HOST";
-pub const KVSRV_ADVERTISE_HOST: &str = "KVSRV_ADVERTISE_HOST";
-pub const KVSRV_API_PORT: &str = "KVSRV_API_PORT";
-pub const KVSRV_RAFT_DIR: &str = "KVSRV_RAFT_DIR";
-pub const KVSRV_NO_SYNC: &str = "KVSRV_NO_SYNC";
-pub const KVSRV_SNAPSHOT_LOGS_SINCE_LAST: &str = "KVSRV_SNAPSHOT_LOGS_SINCE_LAST";
-pub const KVSRV_HEARTBEAT_INTERVAL: &str = "KVSRV_HEARTBEAT_INTERVAL";
-pub const KVSRV_INSTALL_SNAPSHOT_TIMEOUT: &str = "KVSRV_INSTALL_SNAPSHOT_TIMEOUT";
-pub const KVSRV_BOOT: &str = "KVSRV_BOOT";
-pub const KVSRV_SINGLE: &str = "KVSRV_SINGLE";
-pub const KVSRV_ID: &str = "KVSRV_ID";
-
-pub const DEFAULT_LISTEN_HOST: &str = "127.0.0.1";
-
-#[derive(Clone, Debug, PartialEq, Serialize, Deserialize, Parser)]
-#[serde(default)]
+#[derive(Clone, Debug, PartialEq)]
 pub struct RaftConfig {
     /// Identify a config.
     /// This is only meant to make debugging easier with more than one Config involved.
-    #[clap(long, default_value = "")]
     pub config_id: String,
 
     /// The local listening host for metadata communication.
     /// This config does not need to be stored in raft-store,
     /// only used when metasrv startup and listen to.
-    #[clap(long, env = KVSRV_LISTEN_HOST, default_value = DEFAULT_LISTEN_HOST)]
     pub raft_listen_host: String,
 
     /// The hostname that other nodes will use to connect this node.
     /// This host should be stored in raft store and be replicated to the raft cluster,
     /// i.e., when calling add_node().
     /// Use `localhost` by default.
-    #[clap(long, env = KVSRV_ADVERTISE_HOST, default_value = "localhost")]
     pub raft_advertise_host: String,
 
     /// The listening port for metadata communication.
-    #[clap(long, env = KVSRV_API_PORT, default_value = "28004")]
     pub raft_api_port: u32,
 
     /// The dir to store persisted meta state, including raft logs, state machine etc.
-    #[clap(long, env = KVSRV_RAFT_DIR, default_value = "./_meta")]
     pub raft_dir: String,
 
     /// Whether to fsync meta to disk for every meta write(raft log, state machine etc).
     /// No-sync brings risks of data loss during a crash.
     /// You should only use this in a testing environment, unless YOU KNOW WHAT YOU ARE DOING.
-    #[clap(long, env = KVSRV_NO_SYNC)]
     pub no_sync: bool,
 
     /// The number of logs since the last snapshot to trigger next snapshot.
-    #[clap(long, env = KVSRV_SNAPSHOT_LOGS_SINCE_LAST, default_value = "1024")]
     pub snapshot_logs_since_last: u64,
 
     /// The interval in milli seconds at which a leader send heartbeat message to followers.
     /// Different value of this setting on leader and followers may cause unexpected behavior.
-    #[clap(long, env = KVSRV_HEARTBEAT_INTERVAL, default_value = "1000")]
     pub heartbeat_interval: u64,
 
     /// The max time in milli seconds that a leader wait for install-snapshot ack from a follower or non-voter.
-    #[clap(long, env = KVSRV_INSTALL_SNAPSHOT_TIMEOUT, default_value = "4000")]
     pub install_snapshot_timeout: u64,
 
     /// The maximum number of applied logs to keep before purging
-    #[clap(long, env = "RAFT_MAX_APPLIED_LOG_TO_KEEP", default_value = "1000")]
     pub max_applied_log_to_keep: u64,
 
     /// Single node metasrv. It creates a single node cluster if meta data is not initialized.
     /// Otherwise it opens the previous one.
     /// This is mainly for testing purpose.
-    #[clap(long, env = KVSRV_SINGLE)]
     pub single: bool,
 
     /// Bring up a metasrv node and join a cluster.
     ///
     /// The value is one or more addresses of a node in the cluster, to which this node sends a `join` request.
-    #[clap(
-        long,
-        env = "METASRV_JOIN",
-        multiple_occurrences = true,
-        multiple_values = true
-    )]
     pub join: Vec<String>,
 
     /// The node id. Only used when this server is not initialized,
     ///  e.g. --boot or --single for the first time.
     ///  Otherwise this argument is ignored.
-    #[clap(long, env = KVSRV_ID, default_value = "0")]
     pub id: NodeId,
 
     /// For test only: specifies the tree name prefix
-    #[clap(long, default_value = "")]
     pub sled_tree_prefix: String,
 }
 
@@ -147,15 +110,11 @@ pub fn get_default_raft_advertise_host() -> String {
     }
 }
 
-pub fn get_default_raft_listen_host() -> String {
-    DEFAULT_LISTEN_HOST.to_string()
-}
-
 impl Default for RaftConfig {
     fn default() -> Self {
         Self {
             config_id: "".to_string(),
-            raft_listen_host: get_default_raft_listen_host(),
+            raft_listen_host: "127.0.0.1".to_string(),
             raft_advertise_host: get_default_raft_advertise_host(),
             raft_api_port: 28004,
             raft_dir: "./_meta".to_string(),
@@ -173,15 +132,6 @@ impl Default for RaftConfig {
 }
 
 impl RaftConfig {
-    /// StructOptToml provides a default Default impl that loads config from cli args,
-    /// which conflicts with unit test if case-filter arguments passed, e.g.:
-    /// `cargo test my_unit_test_fn`
-    ///
-    /// Thus we need another method to generate an empty default instance.
-    pub fn empty() -> Self {
-        <Self as Parser>::parse_from(&Vec::<&'static str>::new())
-    }
-
     pub fn raft_api_listen_host_string(&self) -> String {
         format!("{}:{}", self.raft_listen_host, self.raft_api_port)
     }

common/meta/raft-store/tests/it/testing.rs

@@ -25,9 +25,10 @@ pub struct RaftTestContext {
 /// Create a new context for testing sled
 pub fn new_raft_test_context() -> RaftTestContext {
     // config for unit test of sled db, meta_sync() is true by default.
-    let mut config = RaftConfig::empty();
-
-    config.sled_tree_prefix = format!("test-{}-", 30900 + GlobalSequence::next());
+    let config = RaftConfig {
+        sled_tree_prefix: format!("test-{}-", 30900 + GlobalSequence::next()),
+        ..Default::default()
+    };
 
     RaftTestContext {
         raft_config: config,

metasrv/Cargo.toml

@@ -52,7 +52,9 @@ poem = { version = "=1.3.16", features = ["rustls"] }
 prometheus = { version = "0.13.0", features = ["process"] }
 prost = "=0.9.0"
 serde = { version = "1.0.136", features = ["derive"] }
+serde-bridge = "0.0.3"
 serde_json = "1.0.79"
+serfig = "0.0.2"
 tempfile = "3.3.0"
 tokio-stream = "0.1.8"
 tonic = { version = "=0.6.2", features = ["tls"] }
@@ -64,3 +66,5 @@ maplit = "1.0.2"
 pretty_assertions = "1.2.1"
 regex = "1.5.5"
 reqwest = { version = "0.11.10", features = ["json"] }
+temp-env = "0.2.0"
+env_logger = "0.9.0"

metasrv/src/configs/inner.rs

@@ -0,0 +1,80 @@
+// Copyright 2022 Datafuse Labs.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use common_meta_raft_store::config::RaftConfig;
+use common_meta_types::MetaResult;
+
+use super::outer_v0::Config as OuterV0Config;
+
+#[derive(Clone, Debug, PartialEq)]
+pub struct Config {
+    pub config_file: String,
+    pub log_level: String,
+    pub log_dir: String,
+    pub metric_api_address: String,
+    pub admin_api_address: String,
+    pub admin_tls_server_cert: String,
+    pub admin_tls_server_key: String,
+    pub grpc_api_address: String,
+    /// Certificate for server to identify itself
+    pub grpc_tls_server_cert: String,
+    pub grpc_tls_server_key: String,
+    pub raft_config: RaftConfig,
+}
+
+impl Default for Config {
+    fn default() -> Self {
+        Self {
+            config_file: "".to_string(),
+            log_level: "INFO".to_string(),
+            log_dir: "./_logs".to_string(),
+            metric_api_address: "127.0.0.1:28001".to_string(),
+            admin_api_address: "127.0.0.1:28002".to_string(),
+            admin_tls_server_cert: "".to_string(),
+            admin_tls_server_key: "".to_string(),
+            grpc_api_address: "127.0.0.1:9191".to_string(),
+            grpc_tls_server_cert: "".to_string(),
+            grpc_tls_server_key: "".to_string(),
+            raft_config: Default::default(),
+        }
+    }
+}
+
+impl Config {
+    /// As requires by [RFC: Config Backward Compatibility](https://github.com/datafuselabs/databend/pull/5324), we will load user's config via wrapper [`OuterV0Config`] and than convert from [`OuterV0Config`] to [`Config`].
+    ///
+    /// In the future, we could have `ConfigV1` and `ConfigV2`.
+    pub fn load() -> MetaResult<Self> {
+        let cfg = OuterV0Config::load()?.try_into()?;
+
+        Ok(cfg)
+    }
+
+    /// Transform config into the outer style.
+    ///
+    /// This function should only be used for end-users.
+    ///
+    /// For examples:
+    ///
+    /// - system config table
+    /// - HTTP Handler
+    /// - tests
+    pub fn into_outer(self) -> OuterV0Config {
+        OuterV0Config::from(self)
+    }
+
+    pub fn tls_rpc_server_enabled(&self) -> bool {
+        !self.grpc_tls_server_key.is_empty() && !self.grpc_tls_server_cert.is_empty()
+    }
+}

metasrv/src/configs/mod.rs

@@ -12,6 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-pub mod config;
+mod inner;
+mod outer_v0;
 
-pub use config::Config;
+pub use inner::Config;