Implement HTTP protocol

Cargo.toml

@@ -19,6 +19,7 @@ members = [
     "src/net",
     "src/protocol/admin",
     "src/protocol/common",
+    "src/protocol/http",
     "src/protocol/memcache",
     "src/protocol/ping",
     "src/protocol/resp",
@@ -38,22 +39,26 @@ members = [
 
 [workspace.dependencies]
 ahash = "0.8.0"
+arrayvec = "0.7.2"
 backtrace = "0.3.66"
 bitvec = "1.0.1"
 blake3 = "1.3.1"
 boring = "2.1.0"
 boring-sys = "2.1.0"
+bstr = "1.0.1"
 bytes = "1.2.1"
 clap = "2.33.3"
 crossbeam-channel = "0.5.6"
 crossbeam-queue = "0.3.5"
 foreign-types-shared = "0.3.1"
+httparse = "1.8.0"
 libc = "0.2.134"
 log = "0.4.17"
 memmap2 = "0.2.2"
 metrohash = "1.0.6"
 mio = "0.8.4"
 nom = "5.1.2"
+phf = "0.11.1"
 proc-macro2 = "1.0.46"
 quote = "1.0.21"
 rand = "0.8.5"
@@ -70,6 +75,7 @@ thiserror = "1.0.24"
 tiny_http = "0.11.0"
 toml = "0.5.9"
 twox-hash = { version = "1.6.3", default-features = false }
+urlencoding = "2.1.2"
 zookeeper = "0.6.1"
 
 [profile.release]

src/protocol/http/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+name = "protocol-http"
+version = { workspace = true }
+edition = { workspace = true }
+license = { workspace = true }
+homepage = { workspace = true }
+repository = { workspace = true }
+
+[dependencies]
+arrayvec = { workspace = true }
+bytes = { workspace = true }
+bstr = { workspace = true }
+httparse = { workspace = true }
+phf = { workspace = true, features = ["macros"] }
+thiserror = { workspace = true }
+urlencoding = { workspace = true }
+
+protocol-common = { path = "../common" }
+logger = { path = "../../logger" }
+
+[dev-dependencies]
+assert_matches = "1.5.0"

src/protocol/http/src/error.rs

@@ -0,0 +1,62 @@
+// Copyright 2022 Twitter, Inc.
+// Licensed under the Apache License, Version 2.0
+// http://www.apache.org/licenses/LICENSE-2.0
+
+use crate::Response;
+
+#[derive(Debug, Error)]
+pub enum Error {
+    #[error("unable to parse request")]
+    Unparseable(#[from] httparse::Error),
+    #[error("Content-Length header was invalid")]
+    BadContentLength,
+    #[error("Content-Length header was missing")]
+    MissingContentLength,
+    #[error("method was unsupported")]
+    BadRequestMethod,
+
+    /// Contains the number of additional bytes needed to parse the rest of the
+    /// request, if known.
+    #[error("not enough data present to parse the whole request")]
+    PartialRequest(Option<usize>),
+
+    #[error("an internal error occurred: {0}")]
+    InternalError(&'static str),
+}
+
+impl Error {
+    pub fn to_response(&self) -> Response {
+        match self {
+            Self::Unparseable(e) => Response::builder(400)
+                .should_close(true)
+                .header("Content-Type", b"text/plain")
+                .body(format!("Unable to parse request: {}", e).as_bytes()),
+            Self::BadRequestMethod => Response::builder(405)
+                .should_close(true)
+                .header("Content-Type", b"text/plain")
+                .body(
+                    format!("Unsupported method, only GET, PUT, and DELETE are supported")
+                        .as_bytes(),
+                ),
+            Self::BadContentLength => Response::builder(400)
+                .should_close(true)
+                .header("Content-Type", b"text/plain")
+                .body(format!("Content-Length header was invalid").as_bytes()),
+            Self::MissingContentLength => Response::builder(411)
+                .should_close(true)
+                .header("Content-Type", b"text/plain")
+                .body(
+                    format!("A Content-Length header is required for all PUT requests").as_bytes(),
+                ),
+            Self::InternalError(message) => Response::builder(500)
+                .should_close(true)
+                .header("Content-Type", b"text/plain")
+                .body(message.as_bytes()),
+
+            Self::PartialRequest(_) => Response::builder(500)
+                .should_close(true)
+                .header("Content-Type", b"text/plain")
+                .body(b"internal server error"),
+        }
+    }
+}

src/protocol/http/src/lib.rs

@@ -0,0 +1,38 @@
+// Copyright 2022 Twitter, Inc.
+// Licensed under the Apache License, Version 2.0
+// http://www.apache.org/licenses/LICENSE-2.0
+
+//! HTTP protocol for pelikan.
+//!
+//! This crate contains definitions for a basic REST protocol for interacting
+//! with a cache. It supports just 3 operations:
+//! - `GET` - get the value associated with the provided key, if present
+//! - `PUT` - set the value associated with the provided key
+//! - `DELETE` - remove a key from the cache
+//!
+//! In all cases the key is passed in as the request path in the request
+//! and the value is passed in as the request body. The protocol supports
+//! reusing the HTTP connection for multiple requests. The only length
+//! specification supported by pelikan is setting the Content-Length header.
+
+#[macro_use]
+extern crate thiserror;
+
+mod error;
+pub mod request;
+pub mod response;
+mod util;
+
+pub use crate::error::Error;
+pub use crate::request::Headers;
+pub use crate::request::{ParseData, Request, RequestData, RequestParser};
+pub use crate::response::Response;
+
+pub type Result<T> = std::result::Result<T, Error>;
+pub type ParseResult = Result<Request>;
+
+pub trait Storage {
+    fn get(&mut self, key: &[u8], headers: &Headers) -> Response;
+    fn put(&mut self, key: &[u8], value: &[u8], headers: &Headers) -> Response;
+    fn delete(&mut self, key: &[u8], headers: &Headers) -> Response;
+}