Detecting Google Project ID with auxiliary function: GoogleEnvironmen…

…t::detect_google_project_id()

README.md

@@ -66,6 +66,7 @@ Looks for credentials in the following places, preferring the first location fou
 - A JSON file in a location known to the gcloud command-line tool.
 - On Google Compute Engine, it fetches credentials from the metadata server.
 
+
 ## Fork
 The library is a fork of [mechiru/googapis](https://github.com/mechiru/googapis) and [mechiru/gouth](https://github.com/mechiru/gouth) to keep up with
 the updates and API proto descriptions from Google more frequently and simplify dependencies management.

examples/firestore-client/src/main.rs

@@ -4,14 +4,17 @@ use gcloud_sdk::*;
 
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
-    let google_project_id = std::env::var("PROJECT_ID")?;
-
     // Debug logging
     let subscriber = tracing_subscriber::fmt()
         .with_env_filter("gcloud_sdk=debug")
         .finish();
     tracing::subscriber::set_global_default(subscriber)?;
 
+    // Detect Google project ID using environment variables PROJECT_ID/GCP_PROJECT_ID
+    // or GKE metadata server when the app runs inside GKE
+    let google_project_id = GoogleEnvironment::detect_google_project_id().await
+        .expect("No Google Project ID detected. Please specify it explicitly using env variable: PROJECT_ID");
+
     let cloud_resource_prefix = format!("projects/{}/databases/(default)", google_project_id);
 
     let firestore_client: GoogleApi<FirestoreClient<GoogleAuthMiddleware>> =

examples/secrets-manager-client/src/main.rs

@@ -4,14 +4,17 @@ use gcloud_sdk::*;
 
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
-    let google_project_id = std::env::var("PROJECT_ID")?;
-
     // Debug logging
     let subscriber = tracing_subscriber::fmt()
         .with_env_filter("gcloud_sdk=debug")
         .finish();
     tracing::subscriber::set_global_default(subscriber)?;
 
+    // Detect Google project ID using environment variables PROJECT_ID/GCP_PROJECT_ID
+    // or GKE metadata server when the app runs inside GKE
+    let google_project_id = GoogleEnvironment::detect_google_project_id().await
+        .expect("No Google Project ID detected. Please specify it explicitly using env variable: PROJECT_ID");
+
     let secrets_client: GoogleApi<SecretManagerServiceClient<GoogleAuthMiddleware>> =
         GoogleApi::from_function(
             SecretManagerServiceClient::new,

gcloud-sdk/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "gcloud-sdk"
-version = "0.17.0"
+version = "0.17.1"
 authors = ["mechiru <[email protected]>", "Abdulla Abdurakhmanov <[email protected]>"]
 edition = "2021"
 license = "MIT OR Apache-2.0"

gcloud-sdk/src/api_client.rs

@@ -45,7 +45,7 @@ where
             google_api_url, token_scopes
         );
 
-        let channel = init_google_services_channel(google_api_url).await?;
+        let channel = GoogleEnvironment::init_google_services_channel(google_api_url).await?;
 
         let token_generator =
             GoogleAuthTokenGenerator::new(token_source_type, token_scopes).await?;
@@ -124,29 +124,54 @@ where
 pub type GoogleAuthMiddleware = GoogleAuthMiddlewareService<Channel>;
 pub type GoogleApi<C> = GoogleApiClient<GoogleApiClientBuilderFunction<C>, C>;
 
-async fn init_google_services_channel(
-    api_url: &'static str,
-) -> Result<Channel, crate::error::Error> {
-    let domain_name = api_url.to_string().replace("https://", "");
-    let tls_config = init_google_services_channel_tls_config(domain_name);
-
-    Ok(Channel::from_static(api_url)
-        .tls_config(tls_config)?
-        .connect_timeout(Duration::from_secs(30))
-        .tcp_keepalive(Some(Duration::from_secs(5)))
-        .keep_alive_timeout(Duration::from_secs(60))
-        .http2_keep_alive_interval(Duration::from_secs(10))
-        .keep_alive_while_idle(true)
-        .connect()
-        .await?)
-}
+pub struct GoogleEnvironment;
+
+impl GoogleEnvironment {
+    pub async fn detect_google_project_id() -> Option<String> {
+        let for_env = std::env::var("PROJECT_ID")
+            .ok()
+            .or_else(|| std::env::var("GCP_PROJECT_ID").ok());
+        if for_env.is_some() {
+            debug!("Detected GCP Project ID using environment variables");
+            for_env
+        } else {
+            let metadata_server = crate::token_source::metadata::Metadata::new(vec![
+                "https://www.googleapis.com/auth/cloud-platform".into(),
+            ]);
+            let metadata_result = metadata_server.detect_google_project_id().await;
+            if metadata_result.is_some() {
+                debug!("Detected GCP Project ID using GKE metadata server");
+            } else {
+                debug!("No GCP Project ID detected in this environment. Please specify it explicitly using environment variables: `PROJECT_ID` or `GCP_PROJECT_ID`");
+            }
+            metadata_result
+        }
+    }
 
-fn init_google_services_channel_tls_config(
-    domain_name: String,
-) -> tonic::transport::ClientTlsConfig {
-    tonic::transport::ClientTlsConfig::new()
-        .ca_certificate(tonic::transport::Certificate::from_pem(
-            crate::apis::CERTIFICATES,
-        ))
-        .domain_name(domain_name)
+    pub async fn init_google_services_channel(
+        api_url: &'static str,
+    ) -> Result<Channel, crate::error::Error> {
+        let domain_name = api_url.to_string().replace("https://", "");
+        let tls_config = Self::init_google_services_channel_tls_config(domain_name);
+
+        Ok(Channel::from_static(api_url)
+            .tls_config(tls_config)?
+            .connect_timeout(Duration::from_secs(30))
+            .tcp_keepalive(Some(Duration::from_secs(5)))
+            .keep_alive_timeout(Duration::from_secs(60))
+            .http2_keep_alive_interval(Duration::from_secs(10))
+            .keep_alive_while_idle(true)
+            .connect()
+            .await?)
+    }
+
+    pub fn init_google_services_channel_tls_config(
+        domain_name: String,
+    ) -> tonic::transport::ClientTlsConfig {
+        tonic::transport::ClientTlsConfig::new()
+            .ca_certificate(tonic::transport::Certificate::from_pem(
+                crate::apis::CERTIFICATES,
+            ))
+            .domain_name(domain_name)
+    }
 }

gcloud-sdk/src/token_source/metadata.rs

@@ -16,11 +16,11 @@ pub struct Metadata {
 }
 
 impl Metadata {
-    fn new(scopes: impl Into<Vec<String>>) -> Self {
+    pub fn new(scopes: impl Into<Vec<String>>) -> Self {
         Self::with_account(scopes, "default")
     }
 
-    fn with_account(scopes: impl Into<Vec<String>>, account: &'static str) -> Self {
+    pub fn with_account(scopes: impl Into<Vec<String>>, account: &'static str) -> Self {
         Self {
             account,
             scopes: scopes.into(),
@@ -38,6 +38,10 @@ impl Metadata {
         };
         format!("instance/service-accounts/{}/token?{}", self.account, query)
     }
+
+    pub async fn detect_google_project_id(&self) -> Option<String> {
+        self.gcemeta_client.project_id().await.ok()
+    }
 }
 
 impl From<Metadata> for BoxSource {

gcloud-sdk/src/token_source/mod.rs

@@ -8,7 +8,7 @@ use chrono::prelude::*;
 
 pub mod auth_token_generator;
 mod credentials;
-mod metadata;
+pub mod metadata;
 
 use serde::{Deserialize, Serialize};