GET /v3/versions mappings field doesn't match docs

[anonymous123-code]

The property mappings should contain a list of objects structured like this:

{
  "gameVersion": "1.12.2",
  "separator": "+build.",
  "build": 1,
  "maven": "org.quiltmc:quilt-mappings:1.12.2+build.1",
  "version": "1.12.2+build.1",
  "hashed": "1.12.2+build.1"
}

But the response looks like this:

{
  //...
  "mappings": [
    "23w12a",
    "1.19.4",
    "1.19.2",
    "1.19.3",
    "1.19.4-rc3",
    "1.19.4-rc2",
    "1.19.4-rc1",
    "1.19.4-pre4",
    "1.19.4-pre3",
    "1.19.4-pre2",
    "1.19.4-pre1",
    "23w07a",
    "23w06a",
    "23w05a",
    "23w04a",
    "23w03a",
    "1.19.3-rc3",
    "1.19.3-rc1",
    "1.19.3-rc2",
    "1.19.3-pre3",
    "1.19.3-pre2",
    "1.19.3-pre1",
    "22w46a",
    "22w45a",
    "22w44a",
    "22w43a",
    "22w42a",
    "1.18.2",
    "1.19.2-rc2",
    "1.19.2-rc1",
    "1.19.1",
    "1.19.1-rc3",
    "1.19.1-rc2",
    "1.19.1-pre6",
    "1.19.1-pre5",
    "1.19.1-pre4",
    "1.19.1-pre3",
    "1.19.1-pre2",
    "1.19.1-rc1",
    "1.19.1-pre1",
    "22w24a",
    "1.19-rc2",
    "1.19",
    "1.19-rc1",
    "1.19-pre5",
    "1.19-pre4",
    "1.19-pre3",
    "1.19-pre2",
    "1.19-pre1",
    "22w19a",
    "22w18a",
    "22w16b",
    "22w17a",
    "22w16a",
    "22w15a",
    "22w14a"
  ]
  //...
}

Based on some skimming this might be a concurrency issue/race condition between populateMappings() and populateQuiltMappings(), both run this.arrays.put("mappings", [...]);.

[Akarys42]

I'm not exactly certain what the issue is. Looking at https://meta.quiltmc.org/v3/versions, everything seems to match?

[anonymous123-code]

Yes, you are right, but the rest of the response matched the docs, so I'm pretty sure I looked up the right route... And I mean if this is a race condition it kinda matches the expected behavior, right?

[Akarys42]

Here is the thing that I don't get, the /v3/version route in prod returns the correct objects, unlike what your issue says

[anonymous123-code]

It is right that current prod is correct, but I'm sure I saw a version of the response broken in the way described above. Given that it worked fine for you it seems likely that some caching was involved. I cant reproduce it anymore now.

However, both populateMappings and populateQuiltMappings in Main are executed asynchronously at

update-quilt-meta/src/main/java/org/quiltmc/Main.java

Lines 89 to 96 in 434e193

	CompletableFuture.allOf(
	this.populateHashedMojmapAndGame(executor),
	this.populateIntermediaryAndGame(executor),
	CompletableFuture.runAsync(this::populateMappings, executor),
	CompletableFuture.runAsync(this::populateQuiltMappings, executor),
	CompletableFuture.runAsync(this::populateInstaller, executor),
	CompletableFuture.runAsync(this.populateLoader(executor), executor)
	).join();

populateMappings reads the qm maven metadata, and generates a JsonArray with the beginning of the version name, which is the mc version, and puts that into this.arrays with the key "mappings"

update-quilt-meta/src/main/java/org/quiltmc/Main.java

Lines 148 to 150 in 434e193

	JsonArray mappings = toJson(this.maven.getMetadata(Constants.GROUP, "quilt-mappings"),
	version -> new JsonPrimitive(stripInfo(version.version)));
	this.arrays.put("mappings", mappings);

populateQuiltMappings builds a list of objects with the properties specified in the spec and puts that into this.arrays with the key "mappings"

update-quilt-meta/src/main/java/org/quiltmc/Main.java

Lines 160 to 190 in 434e193

	JsonArray qm = new JsonArray();
	Map<String, JsonArray> qmVersions = new HashMap<>();
	try {
	for (MavenRepository.ArtifactMetadata.Artifact artifact : this.maven.getMetadata(Constants.GROUP, "quilt-mappings")) {
	JsonObject object = new JsonObject();
	String gameVersion = stripInfo(artifact.version);
	object.addProperty("gameVersion", gameVersion);
	object.addProperty("separator", artifact.version.contains("+build.") ? "+build." : ".");
	object.addProperty("build", Integer.parseInt(artifact.version.substring(artifact.version.lastIndexOf(".") + 1)));
	object.addProperty("maven", artifact.mavenId());
	object.addProperty("version", artifact.version);
	object.addProperty("hashed", gameVersion);
	qm.add(object);
	gameVersions.add(gameVersion);
	qmVersions.computeIfAbsent(gameVersion, v -> new JsonArray()).add(object);
	}
	} catch (IOException e) {
	e.printStackTrace();
	throw new RuntimeException("Failed to get quilt mappings");
	}
	System.out.println("[INFO] Found " + qm.size() + " quilt mappings");
	JsonArray array = new JsonArray();
	gameVersions.forEach(array::add);
	this.arrays.put("mappings", qm);

Then, after both are done, this.arrays.get("mappings") is put into the mappings property of the response.
So, from my understanding, there is a race condition, which either results in the correct format (populateQuiltMappings writes last), or the wrong format (populateMappings writes last)

[Akarys42]

That makes sense, thank you for clarifying

[anonymous123-code]

Im getting the wrong response again

[Akarys42]

Solved by 48d78a4