From ddafdb4fa21faccc413abb4d94b9540771225c7e Mon Sep 17 00:00:00 2001
From: Paul Loyd <pavelko95@gmail.com>
Date: Sun, 9 Jan 2022 17:15:50 +0300
Subject: [PATCH] feat(dumper): `config.path` can include `{class}`

---
 .gitignore                |  2 +-
 CHANGELOG.md              |  1 +
 elfo-dumper/src/actor.rs  | 12 +++++++-----
 elfo-dumper/src/config.rs | 13 +++++++++++--
 elfo/examples/config.toml |  2 +-
 5 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/.gitignore b/.gitignore
index 4bb814b0..b3d88587 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,4 +2,4 @@
 .idea
 Cargo.lock
 
-example.dump
+*.dump
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7779ce2d..5bb95166 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - errors: add `TrySendError::map` and `RequestError::map`.
 - dumping: write `ts` firstly to support the `sort` utility.
 - dumper: extract a dump's name if it's not specified.
+- dumper: support the `{class}` variable in config's `path` param.
 
 ### Fixed
 - init: do not start termination if the memory tracker fails to read files.
diff --git a/elfo-dumper/src/actor.rs b/elfo-dumper/src/actor.rs
index a820a19f..608ab7e1 100644
--- a/elfo-dumper/src/actor.rs
+++ b/elfo-dumper/src/actor.rs
@@ -11,7 +11,7 @@ use fxhash::FxHashSet;
 use metrics::counter;
 use parking_lot::Mutex;
 use tokio::{task, time::Duration};
-use tracing::{debug, error, info, warn};
+use tracing::{error, info, warn};
 
 use elfo_core as elfo;
 use elfo_macros::{message, msg_raw as msg};
@@ -59,7 +59,7 @@ impl Dumper {
     }
 
     async fn main(mut self) -> Result<()> {
-        let mut file = open_file(self.ctx.config()).await;
+        let mut file = open_file(self.ctx.config(), self.ctx.key()).await;
 
         let class = Box::leak(self.ctx.key().clone().into_boxed_str());
         let registry = { self.storage.lock().registry(class) };
@@ -74,15 +74,17 @@ impl Dumper {
 
         while let Some(envelope) = ctx.recv().await {
             msg!(match envelope {
+                // TODO: open on `ValidateConfig`
                 ReopenDumpFile | ConfigUpdated => {
                     let config = ctx.config();
                     interval.set_period(config.interval);
-                    file = open_file(config).await;
+                    file = open_file(config, self.ctx.key()).await;
                 }
                 DumpingTick => {
                     let registry = registry.clone();
                     let timeout = ctx.config().interval;
 
+                    // TODO: run inside scope?
                     let report = task::spawn_blocking(move || -> Result<Report> {
                         let mut errors = Vec::new();
                         let mut written = 0;
@@ -214,13 +216,13 @@ pub(crate) fn new(storage: Arc<Mutex<Storage>>) -> Schema {
         .exec(move |ctx| Dumper::new(ctx, storage_1.clone()).main())
 }
 
-async fn open_file(config: &Config) -> BufWriter<File> {
+async fn open_file(config: &Config, class: &str) -> BufWriter<File> {
     use tokio::fs::OpenOptions;
 
     let file = OpenOptions::new()
         .create(true)
         .append(true)
-        .open(&config.path)
+        .open(&config.path(class))
         .await
         .expect("cannot open the dump file")
         .into_std()
diff --git a/elfo-dumper/src/config.rs b/elfo-dumper/src/config.rs
index e5a9783a..42264354 100644
--- a/elfo-dumper/src/config.rs
+++ b/elfo-dumper/src/config.rs
@@ -1,16 +1,25 @@
-use std::{path::PathBuf, time::Duration};
+use std::time::Duration;
 
 use serde::Deserialize;
 
 #[derive(Debug, Deserialize)]
 pub(crate) struct Config {
-    pub(crate) path: PathBuf,
+    /// A path to a dump file or template:
+    /// * `dumps/all.dump` - one file.
+    /// * `dumps/{class}.dump` - file per class.
+    path: String,
     #[serde(with = "humantime_serde", default = "default_interval")]
     pub(crate) interval: Duration,
     #[serde(default = "default_registry_capacity")]
     pub(crate) registry_capacity: usize,
 }
 
+impl Config {
+    pub(crate) fn path(&self, class: &str) -> String {
+        self.path.replace("{class}", class)
+    }
+}
+
 fn default_interval() -> Duration {
     Duration::from_millis(500)
 }
diff --git a/elfo/examples/config.toml b/elfo/examples/config.toml
index 25dd6fb4..1ad119a3 100644
--- a/elfo/examples/config.toml
+++ b/elfo/examples/config.toml
@@ -34,7 +34,7 @@ address = "0.0.0.0:9042"
 #quantiles = [0.75, 0.9, 0.95, 0.99]
 
 [system.dumpers]
-path = "example.dump"
+path = "example.{class}.dump"
 
 [producers]
 group_count = 3