Deployment Files

All three SDKs can check a deployment file — the .cosmoner/deployment.yaml you commit to describe how a repository deploys — against the format the platform reads. The check runs locally. It needs no API key and makes no network call, so it works in a test suite, a pre-commit hook or an offline build.

import { readFileSync } from "node:fs";
import { validateDeployment } from "@cosmoner/sdk";

const { valid, issues, template } = validateDeployment(
  readFileSync(".cosmoner/deployment.yaml", "utf8"),
);

for (const issue of issues) {
  console.log(`${issue.severity} ${issue.path}: ${issue.message}`);
}

error services.0.run_command: Static sites cannot define a run_command
warning services.0.prot: Unknown field "prot" — it will be ignored

Pass the file's raw text, not a parsed object. To check a file you generated rather than read from disk, use validateDeploymentDocument (validate_deployment_document in Python, Deployment::validateDocument in PHP), which takes the parsed value instead.

The result

template is worth looking at. It is the settings that will actually arrive, so comparing it with what you wrote catches a field that was silently ignored.

Errors and warnings

An error is something the platform would refuse: malformed YAML, a missing required field, two services with the same name.

A warning is something the platform accepts but you probably did not mean. The main one is an unknown key. The platform drops it rather than rejecting the file, so a file written for a newer field still works on an older deploy. Because of that, an unknown key does not fail the check by default — that would reject a file the platform accepts.

To catch typos anyway, pass strict ({ strict: true } in JavaScript, strict=True in Python, strict: true in PHP). It changes the verdict, not the finding: warnings then make valid false.

The same answer everywhere

The JavaScript, Python and PHP validators and the cosmoner validate command are tested against one shared set of example files, and they report the same issues with the same messages in the same order. Checking a file in CI with the CLI and again in a Python deploy script gives you one answer, not two.

Files are read as YAML 1.2, as the platform reads them: autodeploy: yes is the string "yes", not a boolean.

Constants