test: make some `server_fixture` functionality public

This is useful when you want to test a server boot-up with custom
configs.

tests/common/server_fixture.rs

@@ -1,6 +1,7 @@
 use assert_cmd::prelude::*;
 use std::{
     fs::OpenOptions,
+    path::Path,
     process::{Child, Command},
     str,
     sync::{
@@ -21,7 +22,7 @@ use tempfile::TempDir;
 static NEXT_PORT: AtomicUsize = AtomicUsize::new(8090);
 
 /// This structure contains all the addresses a test server should use
-struct BindAddresses {
+pub struct BindAddresses {
     http_port: usize,
     grpc_port: usize,
 
@@ -34,8 +35,18 @@ struct BindAddresses {
 }
 
 impl BindAddresses {
+    pub fn http_bind_addr(&self) -> &str {
+        &self.http_bind_addr
+    }
+
+    pub fn grpc_bind_addr(&self) -> &str {
+        &self.grpc_bind_addr
+    }
+}
+
+impl Default for BindAddresses {
     /// return a new port assignment suitable for this test's use
-    fn new() -> Self {
+    fn default() -> Self {
         let http_port = NEXT_PORT.fetch_add(1, SeqCst);
         let grpc_port = NEXT_PORT.fetch_add(1, SeqCst);
 
@@ -228,6 +239,11 @@ impl ServerFixture {
             tokio::time::sleep(Duration::from_millis(100)).await;
         }
     }
+
+    /// Directory used for data storage.
+    pub fn dir(&self) -> &Path {
+        &self.server.dir.path()
+    }
 }
 
 #[derive(Debug)]
@@ -255,7 +271,7 @@ struct TestServer {
 
 impl TestServer {
     fn new() -> Self {
-        let addrs = BindAddresses::new();
+        let addrs = BindAddresses::default();
         let ready = Mutex::new(ServerState::Started);
 
         let dir = test_helpers::tmp_dir().unwrap();
@@ -309,8 +325,8 @@ impl TestServer {
             .arg("-vv")
             .env("INFLUXDB_IOX_OBJECT_STORE", "file")
             .env("INFLUXDB_IOX_DB_DIR", dir.path())
-            .env("INFLUXDB_IOX_BIND_ADDR", &addrs.http_bind_addr)
-            .env("INFLUXDB_IOX_GRPC_BIND_ADDR", &addrs.grpc_bind_addr)
+            .env("INFLUXDB_IOX_BIND_ADDR", addrs.http_bind_addr())
+            .env("INFLUXDB_IOX_GRPC_BIND_ADDR", addrs.grpc_bind_addr())
             // redirect output to log file
             .stdout(stdout_log_file)
             .stderr(stderr_log_file)
@@ -332,33 +348,7 @@ impl TestServer {
 
         // Poll the RPC and HTTP servers separately as they listen on
         // different ports but both need to be up for the test to run
-        let try_grpc_connect = async {
-            let mut interval = tokio::time::interval(Duration::from_millis(500));
-
-            loop {
-                match self.grpc_channel().await {
-                    Ok(channel) => {
-                        println!("Successfully connected to server");
-
-                        let mut health = influxdb_iox_client::health::Client::new(channel);
-
-                        match health.check_storage().await {
-                            Ok(_) => {
-                                println!("Storage service is running");
-                                return;
-                            }
-                            Err(e) => {
-                                println!("Error checking storage service status: {}", e);
-                            }
-                        }
-                    }
-                    Err(e) => {
-                        println!("Waiting for gRPC API to be up: {}", e);
-                    }
-                }
-                interval.tick().await;
-            }
-        };
+        let try_grpc_connect = wait_for_grpc(self.addrs());
 
         let try_http_connect = async {
             let client = reqwest::Client::new();
@@ -453,9 +443,7 @@ impl TestServer {
     async fn grpc_channel(
         &self,
     ) -> influxdb_iox_client::connection::Result<tonic::transport::Channel> {
-        influxdb_iox_client::connection::Builder::default()
-            .build(&self.addrs().grpc_base)
-            .await
+        grpc_channel(&self.addrs).await
     }
 
     fn addrs(&self) -> &BindAddresses {
@@ -463,6 +451,43 @@ impl TestServer {
     }
 }
 
+/// Create a connection channel for the gRPR endpoint
+pub async fn grpc_channel(
+    addrs: &BindAddresses,
+) -> influxdb_iox_client::connection::Result<tonic::transport::Channel> {
+    influxdb_iox_client::connection::Builder::default()
+        .build(&addrs.grpc_base)
+        .await
+}
+
+pub async fn wait_for_grpc(addrs: &BindAddresses) {
+    let mut interval = tokio::time::interval(Duration::from_millis(500));
+
+    loop {
+        match grpc_channel(addrs).await {
+            Ok(channel) => {
+                println!("Successfully connected to server");
+
+                let mut health = influxdb_iox_client::health::Client::new(channel);
+
+                match health.check_storage().await {
+                    Ok(_) => {
+                        println!("Storage service is running");
+                        return;
+                    }
+                    Err(e) => {
+                        println!("Error checking storage service status: {}", e);
+                    }
+                }
+            }
+            Err(e) => {
+                println!("Waiting for gRPC API to be up: {}", e);
+            }
+        }
+        interval.tick().await;
+    }
+}
+
 impl std::fmt::Display for TestServer {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::result::Result<(), std::fmt::Error> {
         write!(