Improve the error message

Related #327

crates/gpapi/src/gateway/login.rs

@@ -1,5 +1,5 @@
 use anyhow::bail;
-use log::info;
+use log::{info, warn};
 use reqwest::Client;
 use roxmltree::Document;
 use urlencoding::encode;
@@ -7,7 +7,7 @@ use urlencoding::encode;
 use crate::{
   credential::Credential,
   gp_params::GpParams,
-  utils::{normalize_server, remove_url_scheme},
+  utils::{normalize_server, parse_gp_error, remove_url_scheme},
 };
 
 pub async fn gateway_login(gateway: &str, cred: &Credential, gp_params: &GpParams) -> anyhow::Result<String> {
@@ -32,7 +32,14 @@ pub async fn gateway_login(gateway: &str, cred: &Credential, gp_params: &GpParam
   let status = res.status();
 
   if status.is_client_error() || status.is_server_error() {
-    bail!("Gateway login error: {}", status)
+    let (reason, res) = parse_gp_error(res).await;
+
+    warn!(
+      "Gateway login error: reason={}, status={}, response={}",
+      reason, status, res
+    );
+
+    bail!("Gateway login error, reason: {}", reason);
   }
 
   let res_xml = res.text().await?;

crates/gpapi/src/portal/config.rs

@@ -1,5 +1,5 @@
 use anyhow::bail;
-use log::info;
+use log::{info, warn};
 use reqwest::{Client, StatusCode};
 use roxmltree::Document;
 use serde::Serialize;
@@ -10,7 +10,7 @@ use crate::{
   gateway::{parse_gateways, Gateway},
   gp_params::GpParams,
   portal::PortalError,
-  utils::{normalize_server, remove_url_scheme, xml},
+  utils::{normalize_server, parse_gp_error, remove_url_scheme, xml},
 };
 
 #[derive(Debug, Serialize, Type)]
@@ -110,7 +110,14 @@ pub async fn retrieve_config(portal: &str, cred: &Credential, gp_params: &GpPara
   }
 
   if status.is_client_error() || status.is_server_error() {
-    bail!("Portal config error: {}", status)
+    let (reason, res) = parse_gp_error(res).await;
+
+    warn!(
+      "Portal config error: reason={}, status={}, response={}",
+      reason, status, res
+    );
+
+    bail!("Portal config error, reason: {}", reason);
   }
 
   let res_xml = res.text().await.map_err(|e| PortalError::ConfigError(e.to_string()))?;

crates/gpapi/src/portal/prelogin.rs

@@ -1,5 +1,5 @@
 use anyhow::bail;
-use log::info;
+use log::{info, warn};
 use reqwest::{Client, StatusCode};
 use roxmltree::Document;
 use serde::Serialize;
@@ -8,7 +8,7 @@ use specta::Type;
 use crate::{
   gp_params::GpParams,
   portal::PortalError,
-  utils::{base64, normalize_server, xml},
+  utils::{base64, normalize_server, parse_gp_error, xml},
 };
 
 const REQUIRED_PARAMS: [&str; 8] = [
@@ -126,6 +126,10 @@ pub async fn prelogin(portal: &str, gp_params: &GpParams) -> anyhow::Result<Prel
   }
 
   if status.is_client_error() || status.is_server_error() {
+    let (reason, res) = parse_gp_error(res).await;
+
+    warn!("Prelogin error: reason={}, status={}, response={}", reason, status, res);
+
     bail!("Prelogin error: {}", status)
   }
 

crates/gpapi/src/utils/mod.rs

@@ -1,4 +1,4 @@
-use reqwest::Url;
+use reqwest::{Response, Url};
 
 pub(crate) mod xml;
 
@@ -41,3 +41,18 @@ pub fn normalize_server(server: &str) -> anyhow::Result<String> {
 pub fn remove_url_scheme(s: &str) -> String {
   s.replace("http://", "").replace("https://", "")
 }
+
+pub(crate) async fn parse_gp_error(res: Response) -> (String, String) {
+  let reason = res
+    .headers()
+    .get("x-private-pan-globalprotect")
+    .map_or_else(|| "<none>", |v| v.to_str().unwrap_or("<invalid header>"))
+    .to_string();
+
+  let res = res.text().await.map_or_else(
+    |_| "<failed to read response>".to_string(),
+    |v| if v.is_empty() { "<empty>".to_string() } else { v },
+  );
+
+  (reason, res)
+}