Use clap for argument parsing

2 files changed, 42 insertions, 0 deletions

diff --git a/Cargo.toml b/Cargo.toml
index 500b879..6c47745 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,3 +7,8 @@ edition = "2018"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+clap = "2"
+
+[[bin]]
+name = "pg_top"
+path = "src/pg_top.rs"
diff --git a/src/pg_top.rs b/src/pg_top.rs
new file mode 100644
index 0000000..8b632d0
--- /dev/null
+++ b/src/pg_top.rs
@@ -0,0 +1,37 @@
+extern crate clap;
+use clap::{App, Arg};
+use std::thread;
+use std::time::Duration;
+
+fn main() {
+    let matches = App::new("pg_top")
+        .version("5.0.0")
+        .about("'top' for PostgreSQL")
+        .arg(
+            Arg::with_name("DELAY")
+                .help("set delay between screen updates")
+                .default_value("1")
+                .takes_value(true),
+        )
+        .arg(
+            Arg::with_name("COUNT")
+                .help("change number of displays to show")
+                .takes_value(true),
+        )
+        .get_matches();
+
+    let delay = matches.value_of("DELAY").unwrap().parse::<u64>().unwrap();
+    let mut count = if matches.value_of("COUNT").is_none() {
+        1
+    } else {
+        matches.value_of("COUNT").unwrap().parse::<u64>().unwrap()
+    };
+
+    loop {
+        count = count - 1;
+        if count == 0 {
+            break;
+        }
+        thread::sleep(Duration::from_secs(delay));
+    }
+}