Parse prometheus metrics from crdb admin server (#8379)

- Adds a wrapper around the cockroach admin server to query from many
backends
- Parses the output from the admin server (and the underlying CRDB HTTP
server)
- Adds integration tests that validate the data is flowing correctly
- Adds proptests to validate the parsing works

Author: smklein

Cargo.lock

@@ -24,6 +24,7 @@ members = [
     "cockroach-admin",
     "cockroach-admin/api",
     "cockroach-admin/types",
+    "cockroach-metrics",
     "common",
     "dev-tools/cert-dev",
     "dev-tools/clickana",
@@ -175,6 +176,7 @@ default-members = [
     "cockroach-admin",
     "cockroach-admin/api",
     "cockroach-admin/types",
+    "cockroach-metrics",
     "common",
     "dev-tools/cert-dev",
     "dev-tools/clickana",
@@ -549,6 +551,7 @@ num = { version = "0.4.3", default-features = false, features = [ "libm" ] }
 omicron-clickhouse-admin = { path = "clickhouse-admin" }
 omicron-certificates = { path = "certificates" }
 omicron-cockroach-admin = { path = "cockroach-admin" }
+omicron-cockroach-metrics = { path = "cockroach-metrics" }
 omicron-common = { path = "common" }
 omicron-dev-lib = { path = "dev-tools/omicron-dev-lib" }
 omicron-gateway = { path = "gateway" }

Cargo.toml

@@ -0,0 +1,24 @@
+[package]
+name = "omicron-cockroach-metrics"
+version = "0.1.0"
+edition = "2021"
+license = "MPL-2.0"
+
+[dependencies]
+anyhow.workspace = true
+chrono.workspace = true
+cockroach-admin-client.workspace = true
+futures.workspace = true
+serde_json.workspace = true
+slog.workspace = true
+serde.workspace = true
+strum.workspace = true
+tokio.workspace = true
+
+omicron-workspace-hack.workspace = true
+
+[dev-dependencies]
+proptest.workspace = true
+
+[lints]
+workspace = true