Replace structopt with clap (#98)

* Replace `structopt` with `clap`

* Change `port` options from `String` to `u16`

* Shorten clap options config

`name` and `long` use the filed name by default.

Author: palango

Cargo.lock

@@ -25,7 +25,7 @@ async-stream = "0.3.0"
 atoi = "0.3.2"
 bytes = "1"
 rand = "0.8.5"
-structopt = "0.3.14"
+clap = { version = "3.1.18", features = ["derive"] }
 tokio = { version = "1", features = ["full"] }
 tokio-stream = "0.1"
 tracing = "0.1.34"
@@ -45,4 +45,4 @@ opentelemetry-otlp = { version = "0.10.0", optional = true }
 tokio = { version = "1", features = ["test-util"] }
 
 [features]
-otel = ["dep:opentelemetry", "dep:tracing-opentelemetry", "dep:opentelemetry-aws", "dep:opentelemetry-otlp"]
+otel = ["dep:opentelemetry", "dep:tracing-opentelemetry", "dep:opentelemetry-aws", "dep:opentelemetry-otlp"]

Cargo.toml

@@ -1,25 +1,30 @@
 use mini_redis::{client, DEFAULT_PORT};
 
 use bytes::Bytes;
+use clap::{Parser, Subcommand};
 use std::num::ParseIntError;
 use std::str;
 use std::time::Duration;
-use structopt::StructOpt;
 
-#[derive(StructOpt, Debug)]
-#[structopt(name = "mini-redis-cli", version = env!("CARGO_PKG_VERSION"), author = env!("CARGO_PKG_AUTHORS"), about = "Issue Redis commands")]
+#[derive(Parser, Debug)]
+#[clap(
+    name = "mini-redis-cli",
+    version,
+    author,
+    about = "Issue Redis commands"
+)]
 struct Cli {
-    #[structopt(subcommand)]
+    #[clap(subcommand)]
     command: Command,
 
-    #[structopt(name = "hostname", long = "--host", default_value = "127.0.0.1")]
+    #[clap(name = "hostname", long, default_value = "127.0.0.1")]
     host: String,
 
-    #[structopt(name = "port", long = "--port", default_value = DEFAULT_PORT)]
-    port: String,
+    #[clap(long, default_value_t = DEFAULT_PORT)]
+    port: u16,
 }
 
-#[derive(StructOpt, Debug)]
+#[derive(Subcommand, Debug)]
 enum Command {
     /// Get the value of key.
     Get {
@@ -32,19 +37,19 @@ enum Command {
         key: String,
 
         /// Value to set.
-        #[structopt(parse(from_str = bytes_from_str))]
+        #[clap(parse(from_str = bytes_from_str))]
         value: Bytes,
 
         /// Expire the value after specified amount of time
-        #[structopt(parse(try_from_str = duration_from_ms_str))]
+        #[clap(parse(try_from_str = duration_from_ms_str))]
         expires: Option<Duration>,
     },
     ///  Publisher to send a message to a specific channel.
     Publish {
         /// Name of channel
         channel: String,
 
-        #[structopt(parse(from_str = bytes_from_str))]
+        #[clap(parse(from_str = bytes_from_str))]
         /// Message to publish
         message: Bytes,
     },
@@ -70,7 +75,7 @@ async fn main() -> mini_redis::Result<()> {
     tracing_subscriber::fmt::try_init()?;
 
     // Parse command line arguments
-    let cli = Cli::from_args();
+    let cli = Cli::parse();
 
     // Get the remote address to connect to
     let addr = format!("{}:{}", cli.host, cli.port);

src/bin/cli.rs

@@ -8,7 +8,7 @@
 
 use mini_redis::{server, DEFAULT_PORT};
 
-use structopt::StructOpt;
+use clap::Parser;
 use tokio::net::TcpListener;
 use tokio::signal;
 
@@ -32,8 +32,8 @@ use tracing_subscriber::{
 pub async fn main() -> mini_redis::Result<()> {
     set_up_logging()?;
 
-    let cli = Cli::from_args();
-    let port = cli.port.as_deref().unwrap_or(DEFAULT_PORT);
+    let cli = Cli::parse();
+    let port = cli.port.unwrap_or(DEFAULT_PORT);
 
     // Bind a TCP listener
     let listener = TcpListener::bind(&format!("127.0.0.1:{}", port)).await?;
@@ -43,11 +43,11 @@ pub async fn main() -> mini_redis::Result<()> {
     Ok(())
 }
 
-#[derive(StructOpt, Debug)]
-#[structopt(name = "mini-redis-server", version = env!("CARGO_PKG_VERSION"), author = env!("CARGO_PKG_AUTHORS"), about = "A Redis server")]
+#[derive(Parser, Debug)]
+#[clap(name = "mini-redis-server", version, author, about = "A Redis server")]
 struct Cli {
-    #[structopt(name = "port", long = "--port")]
-    port: Option<String>,
+    #[clap(long)]
+    port: Option<u16>,
 }
 
 #[cfg(not(feature = "otel"))]

src/bin/server.rs

@@ -55,7 +55,7 @@ use shutdown::Shutdown;
 /// Default port that a redis server listens on.
 ///
 /// Used if no port is specified.
-pub const DEFAULT_PORT: &str = "6379";
+pub const DEFAULT_PORT: u16 = 6379;
 
 /// Error returned by most functions.
 ///