chore: describe latest federation versions

latest_plugin_versions.json

@@ -0,0 +1,9 @@
+{
+  "supergraph": {
+    "repository": "https://github.com/apollographql/federation-rs",
+    "versions": {
+      "latest-0": "v0.37.1",
+      "latest-2": "v2.1.2"
+    }
+  }
+}

tests/installers.rs

@@ -51,3 +51,103 @@ fn get_binstall_scripts_root() -> Utf8PathBuf {
         .join("binstall")
         .join("scripts")
 }
+
+// this test ensures that `./latest_plugin_versions.json` exists and contains valid
+// binary versions that can be downloaded from
+#[test]
+fn latest_plugins_are_valid_versions() {
+    use reqwest::{blocking::Client, Url};
+    use semver::Version;
+    use serde_json::Value;
+    // first, parse ./latest_plugin_versions.json to JSON
+    let latest_json: Value = serde_json::from_str(include_str!("../latest_plugin_versions.json")).expect("could not read latest_plugin_versions.json from the root of the repo, which is needed to supply latest versions to `rover supergraph compsoe`.");
+    let supergraph = latest_json["supergraph"]
+        .as_object()
+        .expect("JSON malformed: top-level `supergraphs` should be an object");
+    // then validate the fields we expect (and are also expected by https://rover.apollo.dev)
+    let versions = supergraph
+        .get("versions")
+        .expect("JSON malformed: `supergraph.versions` did not exist");
+
+    let latest_federation_one = versions
+        .get("latest-0")
+        .expect("JSON malformed: `supergraph.versions.latest-0` did not exist")
+        .as_str()
+        .expect("JSON malformed: `supergraph.versions.latest-0` was not a string");
+
+    assert!(latest_federation_one.starts_with("v"));
+    Version::parse(&latest_federation_one.to_string()[1..])
+        .expect("JSON malformed: `supergraph.versions.latest-0` was not valid semver");
+
+    let latest_federation_two = versions
+        .get("latest-2")
+        .expect("JSON malformed: `supergraph.versions.latest-2` did not exist")
+        .as_str()
+        .expect("JSON malformed: `supergraph.versions.latest-2` was not a string");
+
+    assert!(latest_federation_two.starts_with("v"));
+    Version::parse(&latest_federation_two.to_string()[1..])
+        .expect("JSON malformed: `supergraph.versions.latest-2 was not valid semver");
+
+    let repository = Url::parse(
+        &supergraph
+            .get("repository")
+            .expect("JSON malformed: `supergraph.resitory` does not exist")
+            .as_str()
+            .expect("JSON malformed: `supergraph.repository` is not a string"),
+    )
+    .expect("JSON malformed: `supergraph.repository` is not a valid URL");
+
+    // after validating the fields, make sure we can download the binaries from GitHub
+    let release_url = format!("{}/releases/download/", &repository);
+    let arch = match (std::env::consts::OS, std::env::consts::ARCH) {
+        ("linux", "aarch64" | "arm") => "aarch64-unknown-linux-gnu",
+        ("linux", _) => "x86_64-unknown-linux-gnu",
+        ("macos", _) => "x86_64-apple-darwin",
+        ("windows", _) => "x86_64-pc-windows-msvc",
+        _ => panic!("not linux, macos, or windows OS for this test runner"),
+    };
+    let latest_federation_one = format!(
+        "{url}supergraph@{version}/supergraph-{version}-{arch}.tar.gz",
+        url = &release_url,
+        version = &latest_federation_one
+    );
+    let latest_federation_two = format!(
+        "{url}supergraph@{version}/supergraph-{version}-{arch}.tar.gz",
+        url = &release_url,
+        version = &latest_federation_two
+    );
+    let client = Client::new();
+    client
+        .get(&latest_federation_one)
+        .send()
+        .unwrap_or_else(|e| {
+            panic!(
+                "could not send HEAD request to {}: {}",
+                &latest_federation_one, e
+            )
+        })
+        .error_for_status()
+        .unwrap_or_else(|e| {
+            panic!(
+                "HEAD request to {} failed with a status code: {}",
+                &latest_federation_one, e
+            )
+        });
+    client
+        .get(&latest_federation_two)
+        .send()
+        .unwrap_or_else(|e| {
+            panic!(
+                "could not send HEAD request to {}: {}",
+                &latest_federation_one, e
+            )
+        })
+        .error_for_status()
+        .unwrap_or_else(|e| {
+            panic!(
+                "HEAD request to {} failed with a status code: {}",
+                &latest_federation_one, e
+            )
+        });
+}