From 3687b2d4bed740a9576237b0ad4a13ddabf30033 Mon Sep 17 00:00:00 2001
From: Trinity Pointard <trinity.pointard@gmail.com>
Date: Tue, 14 Dec 2021 18:20:31 +0100
Subject: [PATCH] add config for compression

---
 src/model/block.rs | 13 +++++++---
 src/util/config.rs | 61 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 71 insertions(+), 3 deletions(-)

diff --git a/src/model/block.rs b/src/model/block.rs
index 97cfb6bf..c040a0b2 100644
--- a/src/model/block.rs
+++ b/src/model/block.rs
@@ -107,12 +107,12 @@ impl DataBlock {
 		}
 	}
 
-	/// Verify data integrity. Allocate less than [`verify_get`] and don't consume self, but
+	/// Verify data integrity. Allocate less than [`DataBlock::verify_get`] and don't consume self, but
 	/// does not return the buffer content.
 	pub fn verify(&self, hash: Hash) -> Result<(), Error> {
 		match self {
 			DataBlock::Plain(data) => {
-				if blake2sum(&data) == hash {
+				if blake2sum(data) == hash {
 					Ok(())
 				} else {
 					Err(Error::CorruptData(hash))
@@ -236,7 +236,14 @@ impl BlockManager {
 	/// Send block to nodes that should have it
 	pub async fn rpc_put_block(&self, hash: Hash, data: Vec<u8>) -> Result<(), Error> {
 		let who = self.replication.write_nodes(&hash);
-		let data = DataBlock::from_buffer(data, None); // TODO get compression level from somewhere
+		let compression_level = self
+			.garage
+			.load()
+			.as_ref()
+			.unwrap()
+			.config
+			.compression_level;
+		let data = DataBlock::from_buffer(data, compression_level);
 		self.system
 			.rpc
 			.try_call_many(
diff --git a/src/util/config.rs b/src/util/config.rs
index 33802012..61a749e3 100644
--- a/src/util/config.rs
+++ b/src/util/config.rs
@@ -30,6 +30,13 @@ pub struct Config {
 	// (we can add more aliases for this later)
 	pub replication_mode: String,
 
+	/// Zstd compression level used on data blocks
+	#[serde(
+		deserialize_with = "deserialize_compression",
+		default = "default_compression"
+	)]
+	pub compression_level: Option<i32>,
+
 	/// RPC secret key: 32 bytes hex encoded
 	pub rpc_secret: String,
 
@@ -123,3 +130,57 @@ where
 
 	Ok(ret)
 }
+
+fn default_compression() -> Option<i32> {
+	Some(1)
+}
+
+fn deserialize_compression<'de, D>(deserializer: D) -> Result<Option<i32>, D::Error>
+where
+	D: de::Deserializer<'de>,
+{
+	use std::convert::TryFrom;
+
+	struct OptionVisitor;
+
+	impl<'de> serde::de::Visitor<'de> for OptionVisitor {
+		type Value = Option<i32>;
+		fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
+			formatter.write_str("int or 'none'")
+		}
+
+		fn visit_str<E>(self, value: &str) -> Result<Self::Value, E>
+		where
+			E: de::Error,
+		{
+			if value.eq_ignore_ascii_case("none") {
+				Ok(None)
+			} else {
+				Err(E::custom(format!(
+					"Invalid compression level: '{}', should be a number, or 'none'",
+					value
+				)))
+			}
+		}
+
+		fn visit_i64<E>(self, v: i64) -> Result<Self::Value, E>
+		where
+			E: de::Error,
+		{
+			i32::try_from(v)
+				.map(Some)
+				.map_err(|_| E::custom("Compression level out of bound".to_owned()))
+		}
+
+		fn visit_u64<E>(self, v: u64) -> Result<Self::Value, E>
+		where
+			E: de::Error,
+		{
+			i32::try_from(v)
+				.map(Some)
+				.map_err(|_| E::custom("Compression level out of bound".to_owned()))
+		}
+	}
+
+	deserializer.deserialize_any(OptionVisitor)
+}