initial implementation of a k2v client

Cargo.lock

@@ -504,6 +504,16 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "crypto-mac"
+version = "0.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1d1a86f49236c215f271d40892d5fc950490551400b02ef360692c29815c714"
+dependencies = [
+ "generic-array",
+ "subtle",
+]
+
 [[package]]
 name = "ct-logs"
 version = "0.8.0"
@@ -848,7 +858,7 @@ dependencies = [
  "garage_web",
  "git-version",
  "hex",
- "hmac",
+ "hmac 0.10.1",
  "http",
  "hyper",
  "kuska-sodiumoxide",
@@ -904,7 +914,7 @@ dependencies = [
  "garage_table 0.7.0",
  "garage_util 0.7.0",
  "hex",
- "hmac",
+ "hmac 0.10.1",
  "http",
  "http-range",
  "httpdate 0.3.2",
@@ -1296,6 +1306,16 @@ dependencies = [
  "digest",
 ]
 
+[[package]]
+name = "hmac"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2a2a2320eb7ec0ebe8da8f744d7812d9fc4cb4d09344ac01898dbcb6a20ae69b"
+dependencies = [
+ "crypto-mac 0.11.1",
+ "digest",
+]
+
 [[package]]
 name = "http"
 version = "0.2.6"
@@ -1523,6 +1543,21 @@ dependencies = [
  "serde_json",
 ]
 
+[[package]]
+name = "k2v-client"
+version = "0.1.0"
+dependencies = [
+ "base64",
+ "http",
+ "rusoto_core",
+ "rusoto_credential",
+ "rusoto_signature",
+ "serde",
+ "serde_json",
+ "thiserror",
+ "tokio",
+]
+
 [[package]]
 name = "k8s-openapi"
 version = "0.13.1"
@@ -2533,6 +2568,75 @@ dependencies = [
  "xmlparser",
 ]
 
+[[package]]
+name = "rusoto_core"
+version = "0.48.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1db30db44ea73551326269adcf7a2169428a054f14faf9e1768f2163494f2fa2"
+dependencies = [
+ "async-trait",
+ "base64",
+ "bytes 1.1.0",
+ "crc32fast",
+ "futures",
+ "http",
+ "hyper",
+ "hyper-tls",
+ "lazy_static",
+ "log",
+ "rusoto_credential",
+ "rusoto_signature",
+ "rustc_version",
+ "serde",
+ "serde_json",
+ "tokio",
+ "xml-rs",
+]
+
+[[package]]
+name = "rusoto_credential"
+version = "0.48.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ee0a6c13db5aad6047b6a44ef023dbbc21a056b6dab5be3b79ce4283d5c02d05"
+dependencies = [
+ "async-trait",
+ "chrono",
+ "dirs-next",
+ "futures",
+ "hyper",
+ "serde",
+ "serde_json",
+ "shlex",
+ "tokio",
+ "zeroize",
+]
+
+[[package]]
+name = "rusoto_signature"
+version = "0.48.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a5ae95491c8b4847931e291b151127eccd6ff8ca13f33603eb3d0035ecb05272"
+dependencies = [
+ "base64",
+ "bytes 1.1.0",
+ "chrono",
+ "digest",
+ "futures",
+ "hex",
+ "hmac 0.11.0",
+ "http",
+ "hyper",
+ "log",
+ "md-5",
+ "percent-encoding",
+ "pin-project-lite",
+ "rusoto_credential",
+ "rustc_version",
+ "serde",
+ "sha2",
+ "tokio",
+]
+
 [[package]]
 name = "rustc_version"
 version = "0.4.0"
@@ -2669,9 +2773,9 @@ checksum = "a4a3381e03edd24287172047536f20cabde766e2cd3e65e6b00fb3af51c4f38d"
 
 [[package]]
 name = "serde"
-version = "1.0.136"
+version = "1.0.137"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ce31e24b01e1e524df96f1c2fdd054405f8d7376249a5110886fb4b658484789"
+checksum = "61ea8d54c77f8315140a05f4c7237403bf38b72704d031543aa1d16abbf517d1"
 dependencies = [
  "serde_derive",
 ]
@@ -2697,9 +2801,9 @@ dependencies = [
 
 [[package]]
 name = "serde_derive"
-version = "1.0.136"
+version = "1.0.137"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "08597e7152fcd306f41838ed3e37be9eaeed2b61c42e2117266a554fab4662f9"
+checksum = "1f26faba0c3959972377d3b2d306ee9f71faee9714294e41bb777f83f88578be"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2719,9 +2823,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.79"
+version = "1.0.81"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e8d9fa5c3b304765ce1fd9c4c8a3de2c8db365a5b91be52f186efc675681d95"
+checksum = "9b7ce2b32a1aed03c558dc61a5cd328f15aff2dbc17daad8fb8af04d2100e15c"
 dependencies = [
  "indexmap",
  "itoa",
@@ -2754,6 +2858,12 @@ dependencies = [
  "opaque-debug",
 ]
 
+[[package]]
+name = "shlex"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "43b2853a4d09f215c24cc5489c992ce46052d359b5109343cbafbf26bc62f8a3"
+
 [[package]]
 name = "signal-hook-registry"
 version = "1.4.0"
@@ -2902,9 +3012,9 @@ checksum = "6bdef32e8150c2a081110b42772ffe7d7c9032b606bc226c8260fd97e0976601"
 
 [[package]]
 name = "syn"
-version = "1.0.89"
+version = "1.0.94"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ea297be220d52398dcc07ce15a209fce436d361735ac1db700cab3b6cdfb9f54"
+checksum = "a07e33e919ebcd69113d5be0e4d70c5707004ff45188910106854f38b960df4a"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2957,18 +3067,18 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "1.0.30"
+version = "1.0.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "854babe52e4df1653706b98fcfc05843010039b406875930a70e4d9644e5c417"
+checksum = "bd829fe32373d27f76265620b5309d0340cb8550f523c1dda251d6298069069a"
 dependencies = [
  "thiserror-impl",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.30"
+version = "1.0.31"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "aa32fd3f627f367fe16f893e2597ae3c05020f8bba2666a4e6ea73d377e5714b"
+checksum = "0396bc89e626244658bef819e22d0cc459e795a5ebe878e6ec336d1674a8d79a"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -3535,6 +3645,12 @@ version = "0.32.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "504a2476202769977a040c6364301a3f65d0cc9e3fb08600b2bda150a0488316"
 
+[[package]]
+name = "xml-rs"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2d7d3948613f75c98fd9328cfdcc45acc4d360655289d0a7d4ec931392200a3"
+
 [[package]]
 name = "xmlparser"
 version = "0.13.3"

Cargo.toml

@@ -8,7 +8,8 @@ members = [
 	"src/admin",
 	"src/api",
 	"src/web",
-	"src/garage"
+	"src/garage",
+	"src/k2v-client",
 ]
 
 [profile.dev]

src/k2v-client/Cargo.toml

@@ -0,0 +1,15 @@
+[package]
+name = "k2v-client"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+base64 = "0.13.0"
+http = "0.2.6"
+rusoto_core = "0.48.0"
+rusoto_credential = "0.48.0"
+rusoto_signature = "0.48.0"
+serde = "1.0.137"
+serde_json = "1.0.81"
+thiserror = "1.0.31"
+tokio = "1.17.0"

src/k2v-client/src/error.rs

@@ -0,0 +1,20 @@
+use std::borrow::Cow;
+
+use thiserror::Error;
+
+/// Errors returned by this crate
+#[derive(Error, Debug)]
+pub enum Error {
+	#[error("received invalid response: {0}")]
+	InvalidResponse(Cow<'static, str>),
+	#[error("not found")]
+	NotFound,
+	#[error("io error: {0}")]
+	IoError(#[from] std::io::Error),
+	#[error("rusoto tls error: {0}")]
+	RusotoTls(#[from] rusoto_core::request::TlsError),
+	#[error("rusoto http error: {0}")]
+	RusotoHttp(#[from] rusoto_core::HttpDispatchError),
+	#[error("deserialization error: {0}")]
+	Deserialization(#[from] serde_json::Error),
+}

src/k2v-client/src/lib.rs

@@ -0,0 +1,570 @@
+use std::collections::BTreeMap;
+use std::time::Duration;
+
+use http::header::{ACCEPT, CONTENT_LENGTH, CONTENT_TYPE};
+use http::status::StatusCode;
+use http::HeaderMap;
+
+use rusoto_core::{ByteStream, DispatchSignedRequest, HttpClient};
+use rusoto_credential::AwsCredentials;
+use rusoto_signature::region::Region;
+use rusoto_signature::signature::SignedRequest;
+use serde::de::Error as DeError;
+use serde::{Deserialize, Deserializer, Serialize, Serializer};
+
+use tokio::io::AsyncReadExt;
+
+mod error;
+
+pub use error::Error;
+
+const DEFAULT_TIMEOUT: Duration = Duration::from_secs(5);
+const DEFAULT_POLL_TIMEOUT: Duration = Duration::from_secs(300);
+const SERVICE: &str = "k2v";
+const GARAGE_CAUSALITY_TOKEN: &str = "X-Garage-Causality-Token";
+
+/// Client used to query a K2V server.
+pub struct K2vClient {
+	region: Region,
+	bucket: String,
+	creds: AwsCredentials,
+	client: HttpClient,
+}
+
+impl K2vClient {
+	/// Create a new K2V client.
+	pub fn new(
+		region: Region,
+		bucket: String,
+		creds: AwsCredentials,
+		user_agent: Option<String>,
+	) -> Result<Self, Error> {
+		let mut client = HttpClient::new()?;
+		if let Some(ua) = user_agent {
+			client.local_agent_prepend(ua);
+		} else {
+			client.local_agent_prepend(format!("k2v/{}", env!("CARGO_PKG_VERSION")));
+		}
+		Ok(K2vClient {
+			region,
+			bucket,
+			creds,
+			client,
+		})
+	}
+
+	/// Perform a ReadItem request, reading the value(s) stored for a single pk+sk.
+	pub async fn read_item(
+		&self,
+		partition_key: &str,
+		sort_key: &str,
+	) -> Result<CausalValue, Error> {
+		let mut req = SignedRequest::new(
+			"GET",
+			SERVICE,
+			&self.region,
+			&format!("/{}/{}", self.bucket, partition_key),
+		);
+		req.add_param("sort_key", sort_key);
+		req.add_header(ACCEPT, "application/octet-stream, application/json");
+
+		let res = self.dispatch(req, None).await?;
+
+		let causality = res
+			.causality_token
+			.ok_or_else(|| Error::InvalidResponse("missing causality token".into()))?;
+
+		if res.status == StatusCode::NO_CONTENT {
+			return Ok(CausalValue {
+				causality,
+				value: vec![K2vValue::Tombstone],
+			});
+		}
+
+		match res.content_type.as_deref() {
+			Some("application/octet-stream") => Ok(CausalValue {
+				causality,
+				value: vec![K2vValue::Value(res.body)],
+			}),
+			Some("application/json") => {
+				let value = serde_json::from_slice(&res.body)?;
+				Ok(CausalValue { causality, value })
+			}
+			Some(ct) => Err(Error::InvalidResponse(
+				format!("invalid content type: {}", ct).into(),
+			)),
+			None => Err(Error::InvalidResponse("missing content type".into())),
+		}
+	}
+
+	/// Perform a PollItem request, waiting for the value(s) stored for a single pk+sk to be
+	/// updated.
+	pub async fn poll_item(
+		&self,
+		partition_key: &str,
+		sort_key: &str,
+		causality: CausalityToken,
+		timeout: Option<Duration>,
+	) -> Result<Option<CausalValue>, Error> {
+		let timeout = timeout.unwrap_or(DEFAULT_POLL_TIMEOUT);
+
+		let mut req = SignedRequest::new(
+			"GET",
+			SERVICE,
+			&self.region,
+			&format!("/{}/{}", self.bucket, partition_key),
+		);
+		req.add_param("sort_key", sort_key);
+		req.add_param("causality_token", &causality.0);
+		req.add_param("timeout", &timeout.as_secs().to_string());
+		req.add_header(ACCEPT, "application/octet-stream, application/json;q=0.9");
+
+		let res = self.dispatch(req, Some(timeout + DEFAULT_TIMEOUT)).await?;
+
+		let causality = res
+			.causality_token
+			.ok_or_else(|| Error::InvalidResponse("missing causality token".into()))?;
+
+		if res.status == StatusCode::NOT_MODIFIED {
+			return Ok(None);
+		}
+
+		if res.status == StatusCode::NO_CONTENT {
+			return Ok(Some(CausalValue {
+				causality,
+				value: vec![K2vValue::Tombstone],
+			}));
+		}
+
+		match res.content_type.as_deref() {
+			Some("application/octet-stream") => Ok(Some(CausalValue {
+				causality,
+				value: vec![K2vValue::Value(res.body)],
+			})),
+			Some("application/json") => {
+				let value = serde_json::from_slice(&res.body)?;
+				Ok(Some(CausalValue { causality, value }))
+			}
+			Some(ct) => Err(Error::InvalidResponse(
+				format!("invalid content type: {}", ct).into(),
+			)),
+			None => Err(Error::InvalidResponse("missing content type".into())),
+		}
+	}
+
+	/// Perform an InsertItem request, inserting a value for a single pk+sk.
+	pub async fn insert_item(
+		&self,
+		partition_key: &str,
+		sort_key: &str,
+		value: Vec<u8>,
+		causality: Option<CausalityToken>,
+	) -> Result<(), Error> {
+		let mut req = SignedRequest::new(
+			"PUT",
+			SERVICE,
+			&self.region,
+			&format!("/{}/{}", self.bucket, partition_key),
+		);
+		req.add_param("sort_key", sort_key);
+		req.set_payload(Some(value));
+
+		if let Some(causality) = causality {
+			req.add_header(GARAGE_CAUSALITY_TOKEN, &causality.0);
+		}
+
+		self.dispatch(req, None).await?;
+		Ok(())
+	}
+
+	/// Perform a DeleteItem request, deleting the value(s) stored for a single pk+sk.
+	pub async fn delete_item(
+		&self,
+		partition_key: &str,
+		sort_key: &str,
+		causality: CausalityToken,
+	) -> Result<(), Error> {
+		let mut req = SignedRequest::new(
+			"DELETE",
+			SERVICE,
+			&self.region,
+			&format!("/{}/{}", self.bucket, partition_key),
+		);
+		req.add_param("sort_key", sort_key);
+		req.add_header(GARAGE_CAUSALITY_TOKEN, &causality.0);
+
+		self.dispatch(req, None).await?;
+		Ok(())
+	}
+
+	// TODO poke team, draft doc outdated fot the return type of this endpoint
+	/// Perform a ReadIndex request, listing partition key which have at least one associated
+	/// sort key, and which matches the filter.
+	pub async fn read_index<'a>(
+		&self,
+		filter: Filter<'a>,
+	) -> Result<PaginatedRange<PartitionInfo>, Error> {
+		let mut req =
+			SignedRequest::new("GET", SERVICE, &self.region, &format!("/{}", self.bucket));
+		filter.insert_params(&mut req);
+
+		let res = self.dispatch(req, None).await?;
+
+		let resp: ReadIndexResponse = serde_json::from_slice(&res.body)?;
+
+		let items = resp
+			.partition_keys
+			.into_iter()
+			.map(|ReadIndexItem { pk, info }| (pk, info))
+			.collect();
+
+		Ok(PaginatedRange {
+			items,
+			next_start: resp.next_start,
+		})
+	}
+
+	/// Perform an InsertBatch request, inserting multiple values at once. Note: this operation is
+	/// *not* atomic: it is possible for some sub-operations to fails and others to success. In
+	/// that case, failure is reported.
+	pub async fn insert_batch<'a>(&self, operations: &[BatchInsertOp<'a>]) -> Result<(), Error> {
+		let mut req =
+			SignedRequest::new("POST", SERVICE, &self.region, &format!("/{}", self.bucket));
+
+		let payload = serde_json::to_vec(operations)?;
+		req.set_payload(Some(payload));
+		self.dispatch(req, None).await?;
+		Ok(())
+	}
+
+	/// Perform a ReadBatch request, reading multiple values or range of values at once.
+	pub async fn read_batch<'a>(
+		&self,
+		operations: &[BatchReadOp<'a>],
+	) -> Result<Vec<PaginatedRange<CausalValue>>, Error> {
+		let mut req =
+			SignedRequest::new("POST", SERVICE, &self.region, &format!("/{}", self.bucket));
+		req.add_param("search", "");
+
+		let payload = serde_json::to_vec(operations)?;
+		req.set_payload(Some(payload));
+		let res = self.dispatch(req, None).await?;
+
+		let resp: Vec<BatchReadResponse> = serde_json::from_slice(&res.body)?;
+
+		Ok(resp
+			.into_iter()
+			.map(|e| PaginatedRange {
+				items: e
+					.items
+					.into_iter()
+					.map(|BatchReadItem { sk, ct, v }| {
+						(
+							sk,
+							CausalValue {
+								causality: ct,
+								value: v,
+							},
+						)
+					})
+					.collect(),
+				next_start: e.next_start,
+			})
+			.collect())
+	}
+
+	/// Perform a DeleteBatch request, deleting mutiple values or range of values at once, without
+	/// providing causality information.
+	pub async fn delete_batch<'a>(
+		&self,
+		operations: &[BatchDeleteOp<'a>],
+	) -> Result<Vec<u64>, Error> {
+		let mut req =
+			SignedRequest::new("POST", SERVICE, &self.region, &format!("/{}", self.bucket));
+		req.add_param("delete", "");
+
+		let payload = serde_json::to_vec(operations)?;
+		req.set_payload(Some(payload));
+		let res = self.dispatch(req, None).await?;
+
+		let resp: Vec<BatchDeleteResponse> = serde_json::from_slice(&res.body)?;
+
+		Ok(resp.into_iter().map(|r| r.deleted_items).collect())
+	}
+
+	async fn dispatch(
+		&self,
+		mut req: SignedRequest,
+		timeout: Option<Duration>,
+	) -> Result<Response, Error> {
+		req.sign(&self.creds);
+		let mut res = self
+			.client
+			.dispatch(req, Some(timeout.unwrap_or(DEFAULT_TIMEOUT)))
+			.await?;
+
+		let causality_token = res
+			.headers
+			.remove(GARAGE_CAUSALITY_TOKEN)
+			.map(CausalityToken);
+		let content_type = res.headers.remove(CONTENT_TYPE);
+
+		let body = match res.status {
+			StatusCode::OK => read_body(&mut res.headers, res.body).await?,
+			StatusCode::NO_CONTENT => Vec::new(),
+			StatusCode::NOT_FOUND => return Err(Error::NotFound),
+			StatusCode::NOT_MODIFIED => Vec::new(),
+			_ => {
+				return Err(Error::InvalidResponse(
+					format!("invalid error code: {}", res.status).into(),
+				))
+			}
+		};
+
+		Ok(Response {
+			body,
+			status: res.status,
+			causality_token,
+			content_type,
+		})
+	}
+}
+
+async fn read_body(headers: &mut HeaderMap<String>, body: ByteStream) -> Result<Vec<u8>, Error> {
+	let body_len = headers
+		.get(CONTENT_LENGTH)
+		.and_then(|h| h.parse().ok())
+		.unwrap_or(0);
+	let mut res = Vec::with_capacity(body_len);
+	body.into_async_read().read_to_end(&mut res).await?;
+	Ok(res)
+}
+
+/// An opaque token used to convey causality between operations.
+#[derive(Debug, Clone, PartialEq, Eq, Deserialize, Serialize)]
+#[serde(transparent)]
+pub struct CausalityToken(String);
+
+impl From<String> for CausalityToken {
+	fn from(v: String) -> Self {
+		CausalityToken(v)
+	}
+}
+
+impl From<CausalityToken> for String {
+	fn from(v: CausalityToken) -> Self {
+		v.0
+	}
+}
+
+/// A value in K2V. can be either a binary value, or a tombstone.
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum K2vValue {
+	Tombstone,
+	Value(Vec<u8>),
+}
+
+impl From<Vec<u8>> for K2vValue {
+	fn from(v: Vec<u8>) -> Self {
+		K2vValue::Value(v)
+	}
+}
+
+impl From<Option<Vec<u8>>> for K2vValue {
+	fn from(v: Option<Vec<u8>>) -> Self {
+		match v {
+			Some(v) => K2vValue::Value(v),
+			None => K2vValue::Tombstone,
+		}
+	}
+}
+
+impl<'de> Deserialize<'de> for K2vValue {
+	fn deserialize<D>(d: D) -> Result<Self, D::Error>
+	where
+		D: Deserializer<'de>,
+	{
+		let val: Option<&str> = Option::deserialize(d)?;
+		Ok(match val {
+			Some(s) => {
+				K2vValue::Value(base64::decode(s).map_err(|_| DeError::custom("invalid base64"))?)
+			}
+			None => K2vValue::Tombstone,
+		})
+	}
+}
+
+impl Serialize for K2vValue {
+	fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+	where
+		S: Serializer,
+	{
+		match self {
+			K2vValue::Tombstone => serializer.serialize_none(),
+			K2vValue::Value(v) => {
+				let b64 = base64::encode(v);
+				serializer.serialize_str(&b64)
+			}
+		}
+	}
+}
+
+/// A set of K2vValue and associated causality information.
+#[derive(Debug, Clone)]
+pub struct CausalValue {
+	pub causality: CausalityToken,
+	pub value: Vec<K2vValue>,
+}
+
+/// Result of paginated requests.
+#[derive(Debug, Clone)]
+pub struct PaginatedRange<V> {
+	pub items: BTreeMap<String, V>,
+	pub next_start: Option<String>,
+}
+
+/// Filter for batch operations.
+#[derive(Debug, Default, Clone, Deserialize, Serialize)]
+pub struct Filter<'a> {
+	pub start: Option<&'a str>,
+	pub end: Option<&'a str>,
+	pub prefix: Option<&'a str>,
+	pub limit: Option<u64>,
+	#[serde(default)]
+	pub reverse: bool,
+}
+
+impl<'a> Filter<'a> {
+	fn insert_params(&self, req: &mut SignedRequest) {
+		if let Some(start) = &self.start {
+			req.add_param("start", start);
+		}
+		if let Some(end) = &self.end {
+			req.add_param("end", end);
+		}
+		if let Some(prefix) = &self.prefix {
+			req.add_param("prefix", prefix);
+		}
+		if let Some(limit) = &self.limit {
+			req.add_param("limit", &limit.to_string());
+		}
+		if self.reverse {
+			req.add_param("reverse", "true");
+		}
+	}
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(rename_all = "camelCase")]
+struct ReadIndexResponse<'a> {
+	#[serde(flatten, borrow)]
+	#[allow(dead_code)]
+	filter: Filter<'a>,
+	partition_keys: Vec<ReadIndexItem>,
+	#[allow(dead_code)]
+	more: bool,
+	next_start: Option<String>,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+struct ReadIndexItem {
+	pk: String,
+	#[serde(flatten)]
+	info: PartitionInfo,
+}
+
+/// Information about data stored with a given partition key.
+#[derive(Debug, Clone, Deserialize)]
+pub struct PartitionInfo {
+	pub entries: u64,
+	pub conflicts: u64,
+	pub values: u64,
+	pub bytes: u64,
+}
+
+/// Single sub-operation of an InsertBatch.
+#[derive(Debug, Clone, Serialize)]
+pub struct BatchInsertOp<'a> {
+	#[serde(rename = "pk")]
+	pub partition_key: &'a str,
+	#[serde(rename = "sk")]
+	pub sort_key: &'a str,
+	#[serde(rename = "ct")]
+	pub causality: Option<CausalityToken>,
+	#[serde(rename = "v")]
+	pub value: K2vValue,
+}
+
+/// Single sub-operation of a ReadBatch.
+#[derive(Debug, Default, Clone, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct BatchReadOp<'a> {
+	pub partition_key: &'a str,
+	#[serde(flatten, borrow)]
+	pub filter: Filter<'a>,
+	#[serde(default)]
+	pub single_item: bool,
+	#[serde(default)]
+	pub concflicts_only: bool,
+	#[serde(default)]
+	pub include_tombstones: bool,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(rename_all = "camelCase")]
+struct BatchReadResponse<'a> {
+	#[serde(flatten, borrow)]
+	#[allow(dead_code)]
+	op: BatchReadOp<'a>,
+	items: Vec<BatchReadItem>,
+	#[allow(dead_code)]
+	more: bool,
+	next_start: Option<String>,
+}
+
+#[derive(Debug, Clone, Deserialize)]
+struct BatchReadItem {
+	sk: String,
+	ct: CausalityToken,
+	v: Vec<K2vValue>,
+}
+
+/// Single sub-operation of a DeleteBatch
+#[derive(Debug, Clone, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct BatchDeleteOp<'a> {
+	pub partition_key: &'a str,
+	pub prefix: Option<&'a str>,
+	pub start: Option<&'a str>,
+	pub end: Option<&'a str>,
+	#[serde(default)]
+	pub single_item: bool,
+}
+
+impl<'a> BatchDeleteOp<'a> {
+	pub fn new(partition_key: &'a str) -> Self {
+		BatchDeleteOp {
+			partition_key,
+			prefix: None,
+			start: None,
+			end: None,
+			single_item: false,
+		}
+	}
+}
+
+#[derive(Debug, Clone, Deserialize)]
+#[serde(rename_all = "camelCase")]
+struct BatchDeleteResponse<'a> {
+	#[serde(flatten, borrow)]
+	#[allow(dead_code)]
+	filter: BatchDeleteOp<'a>,
+	deleted_items: u64,
+}
+
+struct Response {
+	body: Vec<u8>,
+	status: StatusCode,
+	causality_token: Option<CausalityToken>,
+	content_type: Option<String>,
+}

src/k2v-client/src/main.rs

@@ -0,0 +1,47 @@
+use k2v_client::*;
+use rusoto_core::credential::{EnvironmentProvider, ProvideAwsCredentials};
+use rusoto_core::Region;
+
+#[tokio::main]
+async fn main() -> Result<(), Error> {
+	// TODO provide a CLI to perform queries
+	let region = Region::Custom {
+		name: "us-east-1".to_owned(),
+		endpoint: "http://172.30.2.1:3903".to_owned(),
+	};
+
+	let creds = EnvironmentProvider::default().credentials().await.unwrap();
+
+	let client = K2vClient::new(region, "my-bucket".to_owned(), creds, None)?;
+
+	client.insert_item("pk", "sk", vec![0x12], None).await?;
+
+	/*
+	dbg!(client.read_item("pk", "sk").await?);
+
+	client.delete_item("patate", "patate", "eFmifSwRtcl4WaJ9LBG1ywAAAAAAAAAC".to_owned().into()).await?;
+
+	dbg!(client.read_index(Filter::default()).await?);
+
+	client.insert_batch(&[
+		BatchInsertOp {
+			partition_key: "pk",
+			sort_key: "sk1",
+			causality: None,
+			value: vec![1,2,3].into(),
+		},
+		BatchInsertOp {
+			partition_key: "pk",
+			sort_key: "sk2",
+			causality: None,
+			value: vec![1,2,4].into(),
+		},
+	]).await?;
+
+	dbg!(client.read_batch(&[BatchReadOp { partition_key: "pk", ..BatchReadOp::default()}]).await?);
+
+	dbg!(client.delete_batch(&[BatchDeleteOp::new("pk")]).await?);
+	*/
+
+	Ok(())
+}