more verbose cli logging command

bin/src/cli.rs

@@ -106,8 +106,9 @@ pub enum SubCmd {
     },
     #[structopt(name = "logging", about = "change logging level")]
     Logging {
-        #[structopt(short = "l", long = "level", help = "change logging level")]
-        level: String,
+        // #[structopt(short = "l", long = "level", help = "change logging level")]
+        #[structopt(subcommand)]
+        level: LoggingLevel,
     },
     #[structopt(name = "state", about = "state management")]
     State {
@@ -193,6 +194,28 @@ pub enum MetricsCmd {
     Clear,
 }
 
+#[derive(StructOpt, PartialEq, Debug)]
+pub enum LoggingLevel {
+    #[structopt(name = "trace", about = "Displays a LOT of logs")]
+    Trace,
+    #[structopt(
+        name = "debug",
+        about = "Displays more logs about the inner workings of Sōzu"
+    )]
+    Debug,
+    #[structopt(name = "error", about = "Displays occurring errors")]
+    Error,
+    #[structopt(name = "warn", about = "Displays warnings about non-critical errors")]
+    Warn,
+    #[structopt(name = "info", about = "Displays logs about normal behaviour of Sōzu")]
+    Info,
+}
+impl std::fmt::Display for LoggingLevel {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+        write!(f, "{:?}", self)
+    }
+}
+
 #[derive(StructOpt, PartialEq, Debug)]
 pub enum StateCmd {
     #[structopt(name = "save", about = "Save state to that file")]

bin/src/ctl/command.rs

@@ -1,4 +1,4 @@
-use crate::cli::MetricsCmd;
+use crate::cli::{LoggingLevel, MetricsCmd};
 use sozu_command::certificate::{calculate_fingerprint, split_certificate_chain};
 use sozu_command::channel::Channel;
 use sozu_command::command::{
@@ -1859,12 +1859,12 @@ pub fn query_metrics(
 pub fn logging_filter(
     channel: Channel<CommandRequest, CommandResponse>,
     timeout: u64,
-    filter: &str,
+    filter: &LoggingLevel,
 ) -> Result<(), anyhow::Error> {
     order_command(
         channel,
         timeout,
-        ProxyRequestData::Logging(String::from(filter)),
+        ProxyRequestData::Logging(filter.to_string().to_lowercase()),
     )
 }