From 1e98ed467afa49b543f22a0fb8ad44306a30c3b8 Mon Sep 17 00:00:00 2001
From: Andrew James <59655451+andrew-james-dev@users.noreply.github.com>
Date: Mon, 12 Aug 2024 02:16:08 +0100
Subject: [PATCH] Directly authenticate Spanner Admin Client (#295)

---
 spanner/src/admin/mod.rs | 38 ++++++++++++++++++++++++++++++++++++++
 spanner/src/reader.rs    |  5 +++++
 2 files changed, 43 insertions(+)

diff --git a/spanner/src/admin/mod.rs b/spanner/src/admin/mod.rs
index 7c748cfb..3aa0001f 100644
--- a/spanner/src/admin/mod.rs
+++ b/spanner/src/admin/mod.rs
@@ -31,6 +31,44 @@ impl Default for AdminClientConfig {
     }
 }
 
+#[cfg(feature = "auth")]
+pub use google_cloud_auth;
+
+#[cfg(feature = "auth")]
+impl AdminClientConfig {
+    pub async fn with_auth(mut self) -> Result<Self, google_cloud_auth::error::Error> {
+        if let Environment::GoogleCloud(_) = self.environment {
+            let ts = google_cloud_auth::token::DefaultTokenSourceProvider::new(Self::auth_config()).await?;
+            self.environment = Environment::GoogleCloud(Box::new(ts))
+        }
+        Ok(self)
+    }
+
+    pub async fn with_credentials(
+        mut self,
+        credentials: google_cloud_auth::credentials::CredentialsFile,
+    ) -> Result<Self, google_cloud_auth::error::Error> {
+        if let Environment::GoogleCloud(_) = self.environment {
+            let ts = google_cloud_auth::token::DefaultTokenSourceProvider::new_with_credentials(
+                Self::auth_config(),
+                Box::new(credentials),
+            )
+            .await?;
+            self.environment = Environment::GoogleCloud(Box::new(ts))
+        }
+        Ok(self)
+    }
+
+    fn auth_config() -> google_cloud_auth::project::Config<'static> {
+        google_cloud_auth::project::Config {
+            audience: Some(crate::apiv1::conn_pool::AUDIENCE),
+            scopes: Some(&crate::apiv1::conn_pool::SCOPES),
+            sub: None,
+            ..Default::default()
+        }
+    }
+}
+
 pub fn default_retry_setting() -> RetrySetting {
     RetrySetting {
         from_millis: 50,
diff --git a/spanner/src/reader.rs b/spanner/src/reader.rs
index 7b0d9a3f..ed798366 100644
--- a/spanner/src/reader.rs
+++ b/spanner/src/reader.rs
@@ -248,6 +248,11 @@ where
         }
     }
 
+    /// Return metadata for all columns
+    pub fn columns_metadata(&self) -> &Arc<Vec<Field>> {
+        &self.rs.fields
+    }
+
     pub fn column_metadata(&self, column_name: &str) -> Option<(usize, Field)> {
         for (i, val) in self.rs.fields.iter().enumerate() {
             if val.name == column_name {