plane black box: one runner boots the real binary against every linked door's case files

crates/busbar-plane-a2a/build.rs

@@ -54,6 +54,15 @@ fn main() -> Result<(), Box<dyn Error>> {
             .join("tests/root/mod.rs")
             .display()
     );
+    // THE BLACK-BOX CASES' ADDRESS (the same `links` row): the root's black-box runner boots the
+    // real binary against every case file here, reading it as `DEP_BUSBAR_DOOR_CELLS_<CRATE>_BLACKBOX`.
+    println!(
+        "cargo::metadata=blackbox={}",
+        PathBuf::from(std::env::var("CARGO_MANIFEST_DIR")?)
+            .join("tests/blackbox")
+            .display()
+    );
+    println!("cargo:rerun-if-changed=tests/blackbox");
     let out_dir = PathBuf::from(std::env::var("OUT_DIR")?);
     let descriptor_path = out_dir.join("a2a-descriptor.bin");
     let mut config = prost_build::Config::new();

crates/busbar-plane-a2a/tests/blackbox/binary-answers-version.json

@@ -0,0 +1,10 @@
+{
+  "schema": "blackbox/1",
+  "case": "the binary carrying this door answers --version",
+  "_comment": "The seed case that proves the root resolves this crate's black-box directory; the plane's served cases are written beside it.",
+  "oracle": "cli|--version",
+  "requires": {"sections": ["agents"]},
+  "steps": [
+    {"validate": {"args": ["--version"], "exit": 0, "stdout_contains": ["busbar "]}}
+  ]
+}

crates/busbar-plane-a2a/tests/blackbox/law7-configured-agent-plane-is-mounted.json

@@ -0,0 +1,66 @@
+{
+  "schema": "blackbox/1",
+  "requires": {
+    "sections": [
+      "agents"
+    ],
+    "features": [
+      "auth-admin-tokens"
+    ]
+  },
+  "credentials": {
+    "signing_key": true
+  },
+  "vars": {
+    "MOCK_KEY": "x",
+    "BUSBAR_ADMIN_TOKEN": "{admin_token}"
+  },
+  "case": "law7: an agents section mounts the agent plane",
+  "_comment": "Law 7's control: the same binary with the `agents:` section serves the agent admin paths, lists the section as an overlay section, and answers its door as a plane door (RFC 6750) to an unauthenticated caller.",
+  "files": {
+    "config.yaml": "listen: \"127.0.0.1:{data_port}\"\nadmin_listen: \"127.0.0.1:{admin_port}\"\nadvanced:\n  allow_destinations: [\"127.0.0.1\"]\nstore: {module: memory}\npublic_url: \"http://127.0.0.1:{data_port}\"\nidentity-providers:\n  admin-tokens:\n    module: admin-tokens\n    token: { env: BUSBAR_ADMIN_TOKEN }\nauth:\n  chain: [keys]\n  signing_key: { file: \"{signing_key_file}\" }\n  admin_auth: [admin-tokens]\nproviders:\n  mock:\n    api_key: { env: MOCK_KEY }\nmodels:\n  test-model:\n    provider: mock\nagents:\n  a1: { url: \"https://a.example/card\", pin: { mechanism: unpinned } }\n",
+    "providers.yaml": "mock:\n  protocol: anthropic\n  base_url: \"http://127.0.0.1:9\"\n  api_key_env: MOCK_KEY\n"
+  },
+  "steps": [
+    {
+      "boot": {
+        "listening": [
+          "data",
+          "admin"
+        ],
+        "within_secs": 120
+      }
+    },
+    {
+      "call": {
+        "port": "admin",
+        "method": "GET",
+        "path": "/api/v1/admin/agents",
+        "bearer": "{admin_token}",
+        "status": 200
+      }
+    },
+    {
+      "call": {
+        "port": "admin",
+        "method": "DELETE",
+        "path": "/api/v1/admin/overlay/limits",
+        "bearer": "{admin_token}",
+        "body_contains": [
+          "`agents`"
+        ]
+      }
+    },
+    {
+      "call": {
+        "port": "data",
+        "method": "POST",
+        "path": "/a2a",
+        "status": 401,
+        "body_contains": [
+          "error_description"
+        ]
+      }
+    }
+  ]
+}

crates/busbar-plane-a2a/tests/blackbox/law7-unconfigured-agent-plane-is-unmounted.json

@@ -0,0 +1,120 @@
+{
+  "schema": "blackbox/1",
+  "requires": {
+    "sections": [
+      "agents"
+    ],
+    "features": [
+      "auth-admin-tokens"
+    ]
+  },
+  "credentials": {
+    "signing_key": true
+  },
+  "vars": {
+    "MOCK_KEY": "x",
+    "BUSBAR_ADMIN_TOKEN": "{admin_token}"
+  },
+  "case": "law7: a 1.5.5 config leaves the agent plane unmounted",
+  "_comment": "Law 7 (core loads a plugin iff its configuration section is present): with no `agents:` section, every agent admin path answers as an unmounted path does, the overlay list names no agent section, and the agent door falls to the catch-all rather than answering as a plane door.",
+  "files": {
+    "config.yaml": "listen: \"127.0.0.1:{data_port}\"\nadmin_listen: \"127.0.0.1:{admin_port}\"\nadvanced:\n  allow_destinations: [\"127.0.0.1\"]\nstore: {module: memory}\npublic_url: \"http://127.0.0.1:{data_port}\"\nidentity-providers:\n  admin-tokens:\n    module: admin-tokens\n    token: { env: BUSBAR_ADMIN_TOKEN }\nauth:\n  chain: [keys]\n  signing_key: { file: \"{signing_key_file}\" }\n  admin_auth: [admin-tokens]\nproviders:\n  mock:\n    api_key: { env: MOCK_KEY }\nmodels:\n  test-model:\n    provider: mock\n",
+    "providers.yaml": "mock:\n  protocol: anthropic\n  base_url: \"http://127.0.0.1:9\"\n  api_key_env: MOCK_KEY\n"
+  },
+  "steps": [
+    {
+      "boot": {
+        "listening": [
+          "data",
+          "admin"
+        ],
+        "within_secs": 120
+      }
+    },
+    {
+      "call": {
+        "port": "admin",
+        "method": "GET",
+        "path": "/api/v1/admin/no-such-path",
+        "bearer": "{admin_token}",
+        "status": 404
+      }
+    },
+    {
+      "call": {
+        "port": "admin",
+        "method": "GET",
+        "path": "/api/v1/admin/agents",
+        "bearer": "{admin_token}",
+        "status": 404
+      }
+    },
+    {
+      "call": {
+        "port": "admin",
+        "method": "GET",
+        "path": "/api/v1/admin/agents/x",
+        "bearer": "{admin_token}",
+        "status": 404
+      }
+    },
+    {
+      "call": {
+        "port": "admin",
+        "method": "PATCH",
+        "path": "/api/v1/admin/agents/x/settings",
+        "bearer": "{admin_token}",
+        "status": 404
+      }
+    },
+    {
+      "call": {
+        "port": "admin",
+        "method": "POST",
+        "path": "/api/v1/admin/agents/x/connect",
+        "bearer": "{admin_token}",
+        "status": 404
+      }
+    },
+    {
+      "call": {
+        "port": "admin",
+        "method": "POST",
+        "path": "/api/v1/admin/agents/x/approve",
+        "bearer": "{admin_token}",
+        "status": 404
+      }
+    },
+    {
+      "call": {
+        "port": "admin",
+        "method": "DELETE",
+        "path": "/api/v1/admin/overlay/limits",
+        "bearer": "{admin_token}",
+        "status": 400,
+        "body_lacks": [
+          "`agents`"
+        ]
+      }
+    },
+    {
+      "call": {
+        "port": "admin",
+        "method": "DELETE",
+        "path": "/api/v1/admin/overlay/agents",
+        "bearer": "{admin_token}",
+        "status": 400
+      }
+    },
+    {
+      "call": {
+        "port": "data",
+        "method": "POST",
+        "path": "/a2a",
+        "body_lacks": [
+          "error_description"
+        ]
+      }
+    }
+  ]
+}

crates/busbar/build.rs

@@ -136,6 +136,12 @@ fn main() {
     for cfg in linked_axis_cfgs(&manifest, &enabled).1 {
         println!("cargo::rustc-check-cfg=cfg({cfg})");
     }
+    // `BUSBAR_LINKED_AXES`: the same set as data, space-separated, so a black-box case's `requires`
+    // reads it at run time rather than a test spelling a `cfg` per axis.
+    println!(
+        "cargo:rustc-env=BUSBAR_LINKED_AXES={}",
+        linked_axis_cfgs(&manifest, &enabled).0.join(" ")
+    );
     for cfg in linked_axis_cfgs(&manifest, &enabled).0 {
         println!("cargo::rustc-cfg={cfg}");
     }
@@ -419,13 +425,25 @@ fn door_cells_source(manifest: &str, enabled: &dyn Fn(&str) -> bool) -> (String,
     let mut cells: Vec<String> = Vec::new();
     let mut missing: Vec<String> = Vec::new();
     let mut files: Vec<String> = Vec::new();
+    let mut blackbox: Vec<String> = Vec::new();
     for (feature, krate) in metadata_map(manifest, "package.metadata.busbar.linked") {
         let is_door = axes
             .iter()
             .any(|(f, a)| *f == feature && a.split_whitespace().any(|x| x == PLANE_DOOR_AXIS));
         if !(enabled(&feature) && is_door) {
             continue;
         }
+        // THE BLACK-BOX CASES the crate states beside its cells (`blackbox=<dir>`, the same
+        // `links` name): read for every door, cells or none, so the runner sees each.
+        let box_var = format!(
+            "DEP_{}_BLACKBOX",
+            door_cells_links(&krate).to_uppercase().replace('-', "_")
+        );
+        println!("cargo:rerun-if-env-changed={box_var}");
+        if let Ok(dir) = env::var(&box_var) {
+            println!("cargo:rerun-if-changed={dir}");
+            blackbox.push(format!("    ({krate:?}, {dir:?}),\n"));
+        }
         let var = format!(
             "DEP_{}_CELLS",
             door_cells_links(&krate).to_uppercase().replace('-', "_")
@@ -472,8 +490,13 @@ fn door_cells_source(manifest: &str, enabled: &dyn Fn(&str) -> bool) -> (String,
          /// Every door plane's root cells: the path the ledger cites them by (the crate's census\n\
          /// mount, `crates/<crate>/tests/root/mod.rs`) and the file its crate states.\n\
          #[allow(dead_code)]\n\
-         static DOOR_CELLS_FILES: &[(&str, &str)] = &[\n{}];\n",
-        files.concat()
+         static DOOR_CELLS_FILES: &[(&str, &str)] = &[\n{}];\n\
+         /// Every door plane's black-box case directory (`blackbox=<dir>` under its `links` name):\n\
+         /// its crate and the directory its crate states.\n\
+         #[allow(dead_code)]\n\
+         static DOOR_BLACKBOX: &[(&str, &str)] = &[\n{}];\n",
+        files.concat(),
+        blackbox.concat()
     );
     (out, files)
 }