Store the session tokens on the credentials file

- Store the tokens
- Read them before requesting a new one
- Make sure to respect the expiration date comming from AWS

Closes #2

Cargo.toml

@@ -8,3 +8,4 @@ clap = "2.31.2"
 rusoto_core = "0.33"
 rusoto_sts = "0.33"
 rust-ini = "0.12"
+chrono = "0.4"

src/main.rs

@@ -2,6 +2,7 @@ extern crate clap;
 extern crate ini;
 extern crate rusoto_core;
 extern crate rusoto_sts;
+extern crate chrono;
 
 use std::env;
 use std::path::Path;
@@ -10,18 +11,13 @@ use std::process::{Command, Stdio};
 
 use ini::Ini;
 use clap::{Arg, App};
-use rusoto_sts::{Sts, StsClient, Credentials, AssumeRoleRequest};
+use rusoto_sts::{Sts, StsClient, AssumeRoleRequest};
 use rusoto_core::{Region};
+use chrono::prelude::*;
 
 const AWS_DEFAULT_CONFIG_PATH: &str = ".aws/credentials";
 const AWS_DEFAULT_SESSION_NAME: &str = "awsudo";
 
-fn inject_environment_with(credentials: Credentials) {
-    env::set_var("AWS_ACCESS_KEY_ID", credentials.access_key_id);
-    env::set_var("AWS_SECRET_ACCESS_KEY", credentials.secret_access_key);
-    env::set_var("AWS_SESSION_TOKEN", credentials.session_token);
-}
-
 fn main() {
     // CLI
     //TODO Extract this to its own module/file/package...
@@ -61,7 +57,7 @@ fn main() {
     // END CLI
 
     //  State manager
-    let conf = match Ini::load_from_file(config_file_path) {
+    let conf = match Ini::load_from_file(config_file_path.clone()) {
         Err(message) => panic!(message),
         Ok(value) => value
     };
@@ -71,43 +67,90 @@ fn main() {
     let mfa_serial = section.get("mfa_serial").unwrap();
     //TODO parse region or default
 
-    //TODO use a debug flag for those
+    // ~~~cached token ~~
+    let file_aws_access_key_id = match section.get("aws_sudo_access_key_id") {
+        Some(value) => value,
+        None => "invalid"
+    };
+    let file_aws_secret_access_key = match section.get("aws_sudo_secret_access_key") {
+        Some(value) => value,
+        None => "invalid"
+    };
+    let file_aws_session_token = match section.get("aws_sudo_session_token") {
+        Some(value) => value,
+        None => "invalid"
+    };
+    let file_aws_session_expiration_date = match section.get("aws_sudo_session_expiration_date") {
+        Some(value) => value,
+        None => "1994-07-03T07:30:00.00Z"
+    };
+
+    let now = Utc::now();
+    let session_expires_at = match file_aws_session_expiration_date.parse::<DateTime<Utc>>() {
+        Ok(value) => value,
+        Err(e) => panic!("{:?}", e)
+    };
+
     println!("role_arn: {:?}", role_arn);
     println!("mfa_serial: {:?}", mfa_serial);
-    // END State Manager
-
-    //TODO Figure where to put this token request interaction...
-    //TODO Get the MFA token only if necessary
-    let mut token = String::new();
-    if !mfa_serial.is_empty() {
-        println!("Please type your MFA token for {:}: ", mfa_serial);
-        match io::stdin().read_line(&mut token) {
-            Ok(_) => {
-                token.pop(); //REMOVES THE \n
-                println!("token: {}", token);
+
+    if file_aws_access_key_id != "invalid" && now <= session_expires_at {
+        env::set_var("AWS_ACCESS_KEY_ID", file_aws_access_key_id);
+        env::set_var("AWS_SECRET_ACCESS_KEY", file_aws_secret_access_key);
+        env::set_var("AWS_SESSION_TOKEN", file_aws_session_token);
+    } else {
+        //TODO use a debug flag for those
+        println!("role_arn: {:?}", role_arn);
+        println!("mfa_serial: {:?}", mfa_serial);
+        // END State Manager
+
+        //TODO Figure where to put this token request interaction...
+        //TODO Get the MFA token only if necessary
+        let mut token = String::new();
+        if !mfa_serial.is_empty() {
+            println!("Please type your MFA token for {:}: ", mfa_serial);
+            match io::stdin().read_line(&mut token) {
+                Ok(_) => {
+                    token.pop(); //REMOVES THE \n
+                    println!("token: {}", token);
+                }
+                Err(error) => println!("error: {}", error),
             }
-            Err(error) => println!("error: {}", error),
         }
-    }
 
-    // Token Generator
-    //TODO Extract this to its own module/file/package...
-    //TODO use the default
-    let sts = StsClient::new(Region::EuCentral1);
-    match sts.assume_role(AssumeRoleRequest{
+        // Token Generator
+        //TODO Extract this to its own module/file/package...
+        //TODO use the default
+        let sts = StsClient::new(Region::EuCentral1);
+        match sts.assume_role(AssumeRoleRequest{
             role_arn: role_arn.to_string(),
             role_session_name: AWS_DEFAULT_SESSION_NAME.to_owned(),
             serial_number: Some(mfa_serial.to_string()),
             token_code: Some(token.to_string()),
             ..Default::default() }).sync() {
-        Err(e) => panic!("{:?}", e),
-        Ok(response) => inject_environment_with(response.credentials.unwrap())
-    };
-    // END Token Generator
+            Err(e) => panic!("{:?}", e),
+            Ok(response) => {
+                let credentials = response.credentials.unwrap();
+                let mut another = match Ini::load_from_file(config_file_path.clone()) {
+                    Err(message) => panic!(message),
+                    Ok(value) => value
+                };
+
+                another.with_section(Some(profile_name))
+                    .set("aws_sudo_access_key_id", credentials.access_key_id.clone())
+                    .set("aws_sudo_secret_access_key", credentials.secret_access_key.clone())
+                    .set("aws_sudo_session_token", credentials.session_token.clone())
+                    .set("aws_sudo_session_expiration_date", credentials.expiration.clone());
+
+                another.write_to_file(config_file_path.clone()).unwrap();
+
+                env::set_var("AWS_ACCESS_KEY_ID", credentials.access_key_id);
+                env::set_var("AWS_SECRET_ACCESS_KEY", credentials.secret_access_key);
+                env::set_var("AWS_SESSION_TOKEN", credentials.session_token);
+            }
 
-    // TODO: Persist token with State Manager
-    //
-    // TODO: Where to put the environment stuff? StateManager?
+        };
+    }
 
     // Command runner
     //TODO Extract this to its own module/file/package...