Add cockroach-admin dropshot server (#5822)

The goal here is to use this server to run `cockroach node decommission`
for expunged cockroach zones. For this initial PR, the only endpoint
provided wraps `cockroach node status`; wrapping `decommission` is not
as trivial so I figured it should go into a separate PR.

There are currently no callers of this service, but stood up an a4x2 and
confirmed I could talk to it from the switch zone via `curl`:

```
root@oxz_switch:~# curl http://[fd00:1122:3344:103::3]:32222/node/status
{"all_nodes":[{"node_id":"1","address":"[fd00:1122:3344:103::3]:32221","sql_address":"[fd00:1122:3344:103::3]:32221","build":"v22.1.9-dirty","started_at":"2024-05-24T16:47:33.137256Z","updated_at":"2024-05-24T19:01:11.345263Z","locality":"","is_available":true,"is_live":true},{"node_id":"2","address":"[fd00:1122:3344:102::3]:32221","sql_address":"[fd00:1122:3344:102::3]:32221","build":"v22.1.9-dirty","started_at":"2024-05-24T16:41:23.877326Z","updated_at":"2024-05-24T19:01:10.946872Z","locality":"","is_available":true,"is_live":true},{"node_id":"3","address":"[fd00:1122:3344:102::4]:32221","sql_address":"[fd00:1122:3344:102::4]:32221","build":"v22.1.9-dirty","started_at":"2024-05-24T16:41:24.020025Z","updated_at":"2024-05-24T19:01:11.112721Z","locality":"","is_available":true,"is_live":true},{"node_id":"4","address":"[fd00:1122:3344:101::4]:32221","sql_address":"[fd00:1122:3344:101::4]:32221","build":"v22.1.9-dirty","started_at":"2024-05-24T16:41:42.706769Z","updated_at":"2024-05-24T19:01:10.944673Z","locality":"","is_available":true,"is_live":true},{"node_id":"5","address":"[fd00:1122:3344:101::3]:32221","sql_address":"[fd00:1122:3344:101::3]:32221","build":"v22.1.9-dirty","started_at":"2024-05-24T16:41:43.079549Z","updated_at":"2024-05-24T19:01:11.326557Z","locality":"","is_available":true,"is_live":true}]}
```

Cargo.toml

@@ -14,6 +14,7 @@ members = [
     "clients/oximeter-client",
     "clients/sled-agent-client",
     "clients/wicketd-client",
+    "cockroach-admin",
     "common",
     "dev-tools/crdb-seed",
     "dev-tools/omdb",
@@ -96,6 +97,7 @@ default-members = [
     "clients/oximeter-client",
     "clients/sled-agent-client",
     "clients/wicketd-client",
+    "cockroach-admin",
     "common",
     "dev-tools/crdb-seed",
     "dev-tools/omdb",
@@ -338,6 +340,7 @@ nexus-test-utils = { path = "nexus/test-utils" }
 nexus-types = { path = "nexus/types" }
 num-integer = "0.1.46"
 num = { version = "0.4.3", default-features = false, features = [ "libm" ] }
+omicron-cockroach-admin = { path = "cockroach-admin" }
 omicron-common = { path = "common" }
 omicron-gateway = { path = "gateway" }
 omicron-nexus = { path = "nexus" }
@@ -483,6 +486,7 @@ typed-rng = { path = "typed-rng" }
 unicode-width = "0.1.11"
 update-common = { path = "update-common" }
 update-engine = { path = "update-engine" }
+url = "2.5.0"
 usdt = "0.5.0"
 uuid = { version = "1.8.0", features = ["serde", "v4"] }
 uzers = "0.11"

cockroach-admin/Cargo.toml

@@ -0,0 +1,40 @@
+[package]
+name = "omicron-cockroach-admin"
+version = "0.1.0"
+edition = "2021"
+license = "MPL-2.0"
+
+[build-dependencies]
+omicron-rpaths.workspace = true
+
+[dependencies]
+anyhow.workspace = true
+camino.workspace = true
+chrono.workspace = true
+clap.workspace = true
+csv.workspace = true
+dropshot.workspace = true
+http.workspace = true
+illumos-utils.workspace = true
+omicron-common.workspace = true
+# See omicron-rpaths for more about the "pq-sys" dependency.
+pq-sys = "*"
+schemars.workspace = true
+slog.workspace = true
+slog-async.workspace = true
+slog-dtrace.workspace = true
+slog-error-chain.workspace = true
+serde.workspace = true
+thiserror.workspace = true
+tokio.workspace = true
+toml.workspace = true
+
+omicron-workspace-hack.workspace = true
+
+[dev-dependencies]
+nexus-test-utils.workspace = true
+omicron-test-utils.workspace = true
+url.workspace = true
+
+[lints]
+workspace = true

cockroach-admin/build.rs

@@ -0,0 +1,10 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+// See omicron-rpaths for documentation.
+// NOTE: This file MUST be kept in sync with the other build.rs files in this
+// repository.
+fn main() {
+    omicron_rpaths::configure_default_omicron_rpaths();
+}

cockroach-admin/src/bin/cockroach-admin.rs

@@ -0,0 +1,79 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+//! Executable program to run the Omicron CockroachDb admin interface (not to be
+//! confused with CockroachDb's built-in HTTP API)
+
+use anyhow::anyhow;
+use camino::Utf8PathBuf;
+use clap::Parser;
+use omicron_cockroach_admin::CockroachCli;
+use omicron_cockroach_admin::Config;
+use omicron_common::cmd::fatal;
+use omicron_common::cmd::CmdError;
+use std::net::SocketAddr;
+use std::net::SocketAddrV6;
+
+#[derive(Debug, Parser)]
+#[clap(name = "cockroach-admin", about = "Omicron CRDB cluster admin server")]
+enum Args {
+    /// Print the OpenAPI Spec document and exit
+    Openapi,
+
+    /// Start the CRDB admin server
+    Run {
+        /// Path to the `cockroach` CLI
+        #[clap(long, action)]
+        path_to_cockroach_binary: Utf8PathBuf,
+
+        /// Socket address for a running cockroach server instance
+        #[clap(long, action)]
+        cockroach_address: SocketAddrV6,
+
+        /// Address on which this server should run
+        #[clap(long, action)]
+        http_address: SocketAddrV6,
+
+        /// Path to the server config file
+        #[clap(long, action)]
+        config_file_path: Utf8PathBuf,
+    },
+}
+
+#[tokio::main]
+async fn main() {
+    if let Err(err) = main_impl().await {
+        fatal(err);
+    }
+}
+
+async fn main_impl() -> Result<(), CmdError> {
+    let args = Args::parse();
+
+    match args {
+        Args::Openapi => omicron_cockroach_admin::run_openapi()
+            .map_err(|e| CmdError::Failure(anyhow!(e))),
+        Args::Run {
+            path_to_cockroach_binary,
+            cockroach_address,
+            http_address,
+            config_file_path,
+        } => {
+            let cockroach_cli =
+                CockroachCli::new(path_to_cockroach_binary, cockroach_address);
+            let mut config = Config::from_file(&config_file_path)
+                .map_err(|err| CmdError::Failure(anyhow!(err)))?;
+            config.dropshot.bind_address = SocketAddr::V6(http_address);
+            let server =
+                omicron_cockroach_admin::start_server(cockroach_cli, config)
+                    .await
+                    .map_err(|err| CmdError::Failure(anyhow!(err)))?;
+            server.await.map_err(|err| {
+                CmdError::Failure(anyhow!(
+                    "server failed after starting: {err}"
+                ))
+            })
+        }
+    }
+}