refactor(cli): define error messages using the failure crate

Signed-off-by: Kevin W Matthews <[email protected]>

Author: KevinWMatthews

Cargo.lock

@@ -9,6 +9,7 @@ repository = "https://github.com/interledger-rs/interledger-rs"
 
 [dependencies]
 clap = { version = "2.33.0", default-features = false }
+failure = { version = "0.1.6", default-features = false }
 http = { version = "0.1.18", default-features = false }
 reqwest = { version = "0.9.21", default-features = false, features = ["default-tls"] }
 serde = { version = "1.0.101", default-features = false }

crates/ilp-cli/Cargo.toml

@@ -1,17 +1,24 @@
 use clap::ArgMatches;
+use failure::Fail;
 use http;
 use reqwest::{self, Client, Response};
 use std::{borrow::Cow, collections::HashMap};
 use tungstenite::{connect, handshake::client::Request};
 use url::Url;
 
-#[derive(Debug)]
+#[derive(Debug, Fail)]
 pub enum Error {
+    #[fail(display = "Usage error")]
     UsageErr(&'static str),
+    #[fail(display = "Error sending request: {}", _0)]
     ClientErr(reqwest::Error),
+    #[fail(display = "Error receiving response: {}", _0)]
     ResponseErr(String),
+    #[fail(display = "Error parsing URL protocol: {}", _0)]
     ProtocolErr(&'static str),
+    #[fail(display = "Error parsing URL: {}", _0)]
     UrlErr(url::ParseError),
+    #[fail(display = "Error connecting to WebSocket host: {}", _0)]
     WebsocketErr(tungstenite::error::Error),
 }
 
@@ -134,7 +141,7 @@ impl NodeClient<'_> {
         let scheme = match url.scheme() {
             "http" => Ok("ws"),
             "https" => Ok("wss"),
-            _ => Err(Error::ProtocolErr("Unexpected URL protocol")),
+            _ => Err(Error::ProtocolErr("Unexpected protocol")),
         }?;
 
         // The scheme has already been sanitized so this should always succeed

crates/ilp-cli/src/interpreter.rs

@@ -19,24 +19,8 @@ pub fn main() {
             // help text for an arbitrary subcommand, but this works just the same.
             app.get_matches_from(s.split(' '));
         }
-        Err(interpreter::Error::ClientErr(e)) => {
-            eprintln!("ILP CLI error: failed to send request: {}", e);
-            exit(1);
-        }
-        Err(interpreter::Error::ResponseErr(e)) => {
-            eprintln!("ILP CLI error: invalid response: {}", e);
-            exit(1);
-        }
-        Err(interpreter::Error::ProtocolErr(e)) => {
-            eprintln!("ILP CLI error: failed to send request: {}", e);
-            exit(1);
-        }
-        Err(interpreter::Error::UrlErr(e)) => {
-            eprintln!("ILP CLI error: failed to send request: {}", e);
-            exit(1);
-        }
-        Err(interpreter::Error::WebsocketErr(e)) => {
-            eprintln!("ILP CLI error: Could not connect to WebSocket host: {}", e);
+        Err(e) => {
+            eprintln!("ILP CLI error: {}", e);
             exit(1);
         }
         Ok(mut response) => match response.text() {