Add coloring disabling with 'ROCKET_CLI_COLORS=off'.

Resolves #703.

contrib/lib/src/serve.rs

@@ -89,7 +89,7 @@ impl ::std::ops::BitOr for Options {
 ///
 /// # Example
 ///
-/// To serve files from this directory at the `/public` path, allowing
+/// To serve files from the `/static` directory at the `/public` path, allowing
 /// `index.html` files to be used to respond to requests for a directory (the
 /// default), you might write the following:
 ///

core/codegen_next/src/lib.rs

@@ -147,7 +147,7 @@ macro_rules! route_attribute {
         /// The generic route attribute is defined as:
         ///
         /// ```text
-        /// generic-route := METHOD ',' path = route
+        /// generic-route := METHOD ',' 'path' '=' route
         /// ```
         ///
         /// # Typing Requirements

core/lib/src/config/mod.rs

@@ -209,13 +209,14 @@ crate use self::toml_ext::LoggedValue;
 use logger;
 use self::Environment::*;
 use self::environment::CONFIG_ENV;
+use logger::COLORS_ENV;
 use self::toml_ext::parse_simple_toml_value;
 use http::uncased::uncased_eq;
 
 const CONFIG_FILENAME: &str = "Rocket.toml";
 const GLOBAL_ENV_NAME: &str = "global";
 const ENV_VAR_PREFIX: &str = "ROCKET_";
-const PREHANDLED_VARS: [&str; 2] = ["ROCKET_CODEGEN_DEBUG", CONFIG_ENV];
+const PREHANDLED_VARS: [&str; 3] = ["ROCKET_CODEGEN_DEBUG", CONFIG_ENV, COLORS_ENV];
 
 /// Wraps `std::result` with the error type of [`ConfigError`].
 pub type Result<T> = ::std::result::Result<T, ConfigError>;

core/lib/src/logger.rs

@@ -1,11 +1,13 @@
 //! Rocket's logging infrastructure.
 
+use std::{fmt, env};
 use std::str::FromStr;
-use std::fmt;
 
 use log;
 use yansi::Paint;
 
+crate const COLORS_ENV: &str = "ROCKET_CLI_COLORS";
+
 struct RocketLogger(LoggingLevel);
 
 /// Defines the different levels for log messages.
@@ -147,7 +149,10 @@ crate fn try_init(level: LoggingLevel, verbose: bool) -> bool {
         return false;
     }
 
-    if !::isatty::stdout_isatty() || (cfg!(windows) && !Paint::enable_windows_ascii()) {
+    if !::isatty::stdout_isatty()
+        || (cfg!(windows) && !Paint::enable_windows_ascii())
+        || env::var_os(COLORS_ENV).map(|v| v == "0" || v == "off").unwrap_or(false)
+    {
         Paint::disable();
     }