cli: Don't emit ANSI codes to stderr

It seems the tracing crate is broken in this respect. Digging
through best practices, `anstream` is used by clap and looks sane.
We're basically just following their example.

Signed-off-by: Colin Walters <[email protected]>

Author: cgwalters

Cargo.lock

@@ -43,6 +43,7 @@ inherits = "release"
 lto = "yes"
 
 [workspace.dependencies]
+anstream = "0.6"
 anyhow = "1.0.82"
 camino = "1.1.6"
 cap-std-ext = "4.0.3"
@@ -55,6 +56,7 @@ indicatif = "0.17.0"
 fn-error-context = "0.2.1"
 libc = "0.2.154"
 openssl = "0.10.72"
+owo-colors = { version = "4" }
 rustix = { "version" = "1", features = ["thread", "net", "fs", "system", "process", "mount"] }
 serde = "1.0.199"
 serde_json = "1.0.116"

Cargo.toml

@@ -14,11 +14,13 @@ default-run = "bootc"
 platforms = ["*-unknown-linux-gnu"]
 
 [dependencies]
+anstream = { workspace = true }
 anyhow = { workspace = true }
 bootc-lib = { version = "1.0", path = "../lib" }
 bootc-utils = { path = "../utils" }
 tokio = { workspace = true, features = ["macros"] }
 log = "0.4.21"
+owo-colors = { workspace = true }
 tracing = { workspace = true }
 
 [lints]

cli/Cargo.toml

@@ -1,5 +1,8 @@
 //! The main entrypoint for bootc, which just performs global initialization, and then
 //! calls out into the library.
+//!
+use std::io::Write as _;
+
 use anyhow::Result;
 
 /// The code called after we've done process global init and created
@@ -32,11 +35,15 @@ fn run() -> Result<()> {
 }
 
 fn main() {
+    use owo_colors::OwoColorize;
+
     // In order to print the error in a custom format (with :#) our
     // main simply invokes a run() where all the work is done.
     // This code just captures any errors.
     if let Err(e) = run() {
-        tracing::error!("{:#}", e);
+        let mut stderr = anstream::stderr();
+        // Don't panic if writing fails
+        let _ = writeln!(stderr, "{}{:#}", "error: ".red(), e);
         std::process::exit(1);
     }
 }

cli/src/main.rs

@@ -0,0 +1,8 @@
+use std assert
+use tap.nu
+
+tap begin "verify bootc status output formats"
+
+assert equal (bootc switch blah:// e>| find "\u{1B}") []
+
+tap ok

tmt/tests/booted/readonly/002-test-cli.nu

@@ -8,7 +8,7 @@ mkfs.ext4 disk.img
 mount -o loop disk.img /var/mnt
 
 # attempt to install to filesystem without specifying a source-imgref
-let result = bootc install to-filesystem /var/mnt e>| ansi strip
-assert equal $result "ERROR Installing to filesystem: Either --source-imgref must be defined or this command must be executed inside a podman container."
+let result = bootc install to-filesystem /var/mnt e>| find "--source-imgref must be defined"
+assert not equal $result null
 
 tap ok