From b34140f27a127b0e49075586707a0d44b8590924 Mon Sep 17 00:00:00 2001
From: Xuanwo <github@xuanwo.io>
Date: Tue, 1 Mar 2022 17:14:27 +0800
Subject: [PATCH] credential: Add Plain variant to allow more input

Signed-off-by: Xuanwo <github@xuanwo.io>
---
 src/credential.rs  | 15 +++++++++++++++
 src/services/s3.rs |  2 ++
 2 files changed, 17 insertions(+)

diff --git a/src/credential.rs b/src/credential.rs
index a85240b20704..caab6b9bde70 100644
--- a/src/credential.rs
+++ b/src/credential.rs
@@ -14,6 +14,9 @@
 
 #[derive(Debug, Clone)]
 pub enum Credential {
+    /// Plain refers to no credential has been provided, fallback to services'
+    /// default logic.
+    Plain,
     /// Basic refers to HTTP Basic Authentication.
     Basic { username: String, password: String },
     /// HMAC, also known as Access Key/Secret Key authentication.
@@ -33,6 +36,10 @@ pub enum Credential {
 
 impl Credential {
     pub fn basic(username: &str, password: &str) -> Credential {
+        if username.is_empty() && password.is_empty() {
+            return Credential::Plain;
+        }
+
         Credential::Basic {
             username: username.to_string(),
             password: password.to_string(),
@@ -40,6 +47,10 @@ impl Credential {
     }
 
     pub fn hmac(access_key_id: &str, secret_access_key: &str) -> Credential {
+        if access_key_id.is_empty() && secret_access_key.is_empty() {
+            return Credential::Plain;
+        }
+
         Credential::HMAC {
             access_key_id: access_key_id.to_string(),
             secret_access_key: secret_access_key.to_string(),
@@ -47,6 +58,10 @@ impl Credential {
     }
 
     pub fn token(token: &str) -> Credential {
+        if token.is_empty() {
+            return Credential::Plain;
+        }
+
         Credential::Token(token.to_string())
     }
 }
diff --git a/src/services/s3.rs b/src/services/s3.rs
index 0f07bc5fcf57..10654d333d50 100644
--- a/src/services/s3.rs
+++ b/src/services/s3.rs
@@ -258,6 +258,8 @@ impl Builder {
                         None,
                     ));
                 }
+                // We don't need to do anything if user tries to read credential from env.
+                Credential::Plain => {}
                 _ => {
                     return Err(Error::Backend {
                         kind: Kind::BackendConfigurationInvalid,