Main: Improve error reporting when failing to read from files

src/main.rs

@@ -1,16 +1,20 @@
-use handlebars::{Context, Handlebars, Helper, HelperResult, JsonRender, Output, RenderContext, RenderErrorReason};
-use serde_json::{Map, Value};
-use std::{env, error::Error};
+use std::env;
 use std::fs;
+
+use anyhow::Result;
+
+use serde_json::{Map, Value};
 use url_escape;
 
-fn main() -> Result<(), Box<dyn Error>> {
+use handlebars::{Context, Handlebars, Helper, HelperResult, JsonRender, Output, RenderContext, RenderErrorReason};
+
+fn main() -> Result<()> {
     let mut handlebars = Handlebars::new();
 
     let path_to_contents = env::args().nth(1).expect("The first argument to be present.");
     let output_path = env::args().nth(2).expect("The second argument to be present.");
 
-    let contents = fs::read_to_string(path_to_contents).expect("To be able to open a file at the path passed as the first argument.");
+    let contents = fs::read_to_string(path_to_contents).expect("To be able to read the contents file at the path '{path_to_contents}' passed as the first argument.");
 
     let secret_inputs = env::vars().filter(|(key, _)| key.starts_with("SECRET_"));
 
@@ -21,7 +25,8 @@ fn main() -> Result<(), Box<dyn Error>> {
             panic!("Secret environment variable is not in format 'name:path_to_secret'");
         };
 
-        let secret_value = fs::read_to_string(path_to_secret)?;
+        let secret_value = fs::read_to_string(path_to_secret)
+            .expect("To be able to read in secret '{secret_key}' from path '{path_to_secret}'");
 
         println!("Registering secret '{secret_key}' from '{path_to_secret}'.");