[cockroach-admin] turn API into a trait (#6129)

Move the more complex types into a shared cockroach-admin-types crate,
and the simple wrappers into the cockroach-admin-api crate.

Cargo.toml

@@ -16,6 +16,8 @@ members = [
     "clients/sled-agent-client",
     "clients/wicketd-client",
     "cockroach-admin",
+    "cockroach-admin/api",
+    "cockroach-admin/types",
     "common",
     "dev-tools/crdb-seed",
     "dev-tools/omdb",
@@ -111,6 +113,8 @@ default-members = [
     "clients/sled-agent-client",
     "clients/wicketd-client",
     "cockroach-admin",
+    "cockroach-admin/api",
+    "cockroach-admin/types",
     "common",
     "dev-tools/crdb-seed",
     "dev-tools/omdb",
@@ -265,7 +269,9 @@ ciborium = "0.2.2"
 cfg-if = "1.0"
 chrono = { version = "0.4", features = [ "serde" ] }
 clap = { version = "4.5", features = ["cargo", "derive", "env", "wrap_help"] }
+cockroach-admin-api = { path = "cockroach-admin/api" }
 cockroach-admin-client = { path = "clients/cockroach-admin-client" }
+cockroach-admin-types = { path = "cockroach-admin/types" }
 colored = "2.1"
 const_format = "0.2.32"
 cookie = "0.18"

cockroach-admin/Cargo.toml

@@ -12,6 +12,8 @@ anyhow.workspace = true
 camino.workspace = true
 chrono.workspace = true
 clap.workspace = true
+cockroach-admin-api.workspace = true
+cockroach-admin-types.workspace = true
 csv.workspace = true
 dropshot.workspace = true
 http.workspace = true

cockroach-admin/api/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "cockroach-admin-api"
+version = "0.1.0"
+edition = "2021"
+license = "MPL-2.0"
+
+[lints]
+workspace = true
+
+[dependencies]
+cockroach-admin-types.workspace = true
+dropshot.workspace = true
+omicron-common.workspace = true
+omicron-uuid-kinds.workspace = true
+omicron-workspace-hack.workspace = true
+schemars.workspace = true
+serde.workspace = true

cockroach-admin/api/src/lib.rs

@@ -0,0 +1,76 @@
+// 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/.
+
+use cockroach_admin_types::{NodeDecommission, NodeStatus};
+use dropshot::{HttpError, HttpResponseOk, RequestContext, TypedBody};
+use omicron_uuid_kinds::OmicronZoneUuid;
+use schemars::JsonSchema;
+use serde::{Deserialize, Serialize};
+
+#[dropshot::api_description {
+    module = "cockroach_admin_api_mod",
+}]
+pub trait CockroachAdminApi {
+    type Context;
+
+    /// Get the status of all nodes in the CRDB cluster.
+    #[endpoint {
+        method = GET,
+        path = "/node/status",
+    }]
+    async fn node_status(
+        rqctx: RequestContext<Self::Context>,
+    ) -> Result<HttpResponseOk<ClusterNodeStatus>, HttpError>;
+
+    /// Get the CockroachDB node ID of the local cockroach instance.
+    #[endpoint {
+        method = GET,
+        path = "/node/id",
+    }]
+    async fn local_node_id(
+        rqctx: RequestContext<Self::Context>,
+    ) -> Result<HttpResponseOk<LocalNodeId>, HttpError>;
+
+    /// Decommission a node from the CRDB cluster.
+    #[endpoint {
+        method = POST,
+        path = "/node/decommission",
+    }]
+    async fn node_decommission(
+        rqctx: RequestContext<Self::Context>,
+        body: TypedBody<NodeId>,
+    ) -> Result<HttpResponseOk<NodeDecommission>, HttpError>;
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Deserialize, Serialize, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub struct ClusterNodeStatus {
+    pub all_nodes: Vec<NodeStatus>,
+}
+
+/// CockroachDB Node ID
+#[derive(Debug, Clone, PartialEq, Eq, Deserialize, Serialize, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub struct LocalNodeId {
+    /// The ID of this Omicron zone.
+    ///
+    /// This is included to ensure correctness even if a socket address on a
+    /// sled is reused for a different zone; if our caller is trying to
+    /// determine the node ID for a particular Omicron CockroachDB zone, they'll
+    /// contact us by socket address. We include our zone ID in the response for
+    /// their confirmation that we are the zone they intended to contact.
+    pub zone_id: OmicronZoneUuid,
+    // CockroachDB node IDs are integers, in practice, but our use of them is as
+    // input and output to the `cockroach` CLI. We use a string which is a bit
+    // more natural (no need to parse CLI output or stringify an ID to send it
+    // as input) and leaves open the door for the format to change in the
+    // future.
+    pub node_id: String,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Deserialize, Serialize, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub struct NodeId {
+    pub node_id: String,
+}

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

@@ -19,9 +19,6 @@ 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
@@ -57,8 +54,6 @@ 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,