Use solana-cli config keypair in solana-keygen (#8074)

* Use solana-cli config keypair in solana-keygen

* s/infile/keypair for consistency across modules and more generality across access methods

* Move config into separate crate

cli-config/Cargo.toml

@@ -0,0 +1,16 @@
+[package]
+authors = ["Solana Maintainers <maintainers@solana.com>"]
+edition = "2018"
+name = "solana-cli-config"
+description = "Blockchain, Rebuilt for Scale"
+version = "0.24.0"
+repository = "https://github.com/solana-labs/solana"
+license = "Apache-2.0"
+homepage = "https://solana.com/"
+
+[dependencies]
+dirs = "2.0.2"
+lazy_static = "1.4.0"
+serde = "1.0.104"
+serde_derive = "1.0.103"
+serde_yaml = "0.8.11"

cli-config/src/config.rs

@@ -0,0 +1,51 @@
+// Wallet settings that can be configured for long-term use
+use serde_derive::{Deserialize, Serialize};
+use std::{
+    fs::{create_dir_all, File},
+    io::{self, Write},
+    path::Path,
+};
+
+lazy_static! {
+    pub static ref CONFIG_FILE: Option<String> = {
+        dirs::home_dir().map(|mut path| {
+            path.extend(&[".config", "solana", "cli", "config.yml"]);
+            path.to_str().unwrap().to_string()
+        })
+    };
+}
+
+#[derive(Serialize, Deserialize, Default, Debug, PartialEq)]
+pub struct Config {
+    pub url: String,
+    pub keypair_path: String,
+}
+
+impl Config {
+    pub fn new(url: &str, keypair_path: &str) -> Self {
+        Self {
+            url: url.to_string(),
+            keypair_path: keypair_path.to_string(),
+        }
+    }
+
+    pub fn load(config_file: &str) -> Result<Self, io::Error> {
+        let file = File::open(config_file.to_string())?;
+        let config = serde_yaml::from_reader(file)
+            .map_err(|err| io::Error::new(io::ErrorKind::Other, format!("{:?}", err)))?;
+        Ok(config)
+    }
+
+    pub fn save(&self, config_file: &str) -> Result<(), io::Error> {
+        let serialized = serde_yaml::to_string(self)
+            .map_err(|err| io::Error::new(io::ErrorKind::Other, format!("{:?}", err)))?;
+
+        if let Some(outdir) = Path::new(&config_file).parent() {
+            create_dir_all(outdir)?;
+        }
+        let mut file = File::create(config_file)?;
+        file.write_all(&serialized.into_bytes())?;
+
+        Ok(())
+    }
+}

cli-config/src/lib.rs

@@ -0,0 +1,4 @@
+#[macro_use]
+extern crate lazy_static;
+
+pub mod config;