/nomad-openapi

OpenAPI specification and related artifacts for HashiCorp Nomad

Primary LanguagePythonMozilla Public License 2.0MPL-2.0

HashiCorp Nomad logo

Overview

This repository contains the HashiCorp Nomad OpenAPI specification and related artifacts.

The OpenAPI specification defines a machine-readable schema for describing HTTP APIs. From an OpenAPI specification, clients and servers for your project can be generated in a number of programming languages.

Quick start

The latest version of the OpenAPI specification for the Version 1 Nomad HTTP API can be found in this repository at v1/openapi.yaml. This file is itself a generated file and should not be edited directly. You can use this file to generate a client for the Nomad HTTP API in the language of your choice.

Using the Go Client

To use the Go client add a reference to it in your go.mod with go get.

$ go get github.com/hashicorp/nomad-openapi

You can use it from your client applications like this.

package main

import (
	"fmt"
	"os"

	v1 "github.com/hashicorp/nomad-openapi/v1"
)

func main() {
	client, err := v1.NewClient()
	if err != nil {
		fmt.Println(err.Error())
	}

	jobName := "example"
	opts := v1.DefaultQueryOpts()

	job, meta, err := client.Jobs().GetJob(opts.Ctx(), jobName)
	if err != nil {
		os.Exit(1)
	}

	fmt.Println(*job.ID)
	fmt.Printf("%v", &meta)
}

Environmental Configuration

This client supports the following Nomad environment variables.

  • NOMAD_ADDR - Required to overide the default of http://127.0.0.1:4646.
  • NOMAD_TOKEN - Required with ACLs enabled. Can be overidden with QueryOpts or WriteOpts.
  • NOMAD_CACERT - Required with TLS enabled.
  • NOMAD_CLIENT_CERT - Required with TLS enabled.
  • NOMAD_CLIENT_KEY - Required with TLS enabled.
  • NOMAD_REGION - Required if you are calling a server in a region other than global as the NOMAD_CACERT SAN will follow the convention of server.<region>.nomad.

Code generation

The OpenAPI ecosystem has a number of existing code generators to choose from. This repository uses the OpenAPI Generator project to generate a test client in Golang that is then used to validate the generated specification.

To generate a ruby client using the OpenAPI Generator, you can use the following docker command from the root of this repository.

$ mkdir -p /tmp/nomad-openapi && docker run \
	--rm \
	-v "$PWD:/local" \
	-v "/tmp/nomad-openapi:/output" \
	openapitools/openapi-generator-cli:v5.2.0 generate -i /local/v1/openapi.yaml -g ruby -o /output/

Generating a client in a different language should be as straightforward as changing the -g argument in the command above to your language of choice. Check the OpenAPI Generators page for a full list of supported languages.

If you want to generate a client in a language not yet included in the clients directory and submit it for inclusion in this repo, review the Makefile at the root of this repository. Also review the config.yaml file in each client folder. You will need to create a similar file that is specific to your language. Reference the OpenAPI Generator documentation for more information on language specific configuration options.

This repository is currently experimental, and, as such, there is no guarantee of support at this time.

Community Guidelines

The HashiCorp community is a mixture of professionals, volunteers, students, and employees who collaborate to make HashiCorp tools better. Community members play a variety of roles, including mentor, teacher, or connector. If you would like to contribute to HashiCorp products, review our community guidelines which can be found online here.

Issues and Questions

If you have any issues or questions using this package, please raise a Github issue in this repository. Issues raised in the main Nomad repository will be redirected here.

Motivation

The OpenAPI specification is ideal if you are working in a greenfield scenario, and can write your specification first. This spec first approach is highly recommended and widely supported by many of the tool vendors and experts in the OpenAPI space.

However, this approach leaves brownfield projects with an existing API that either predates the OpenAPI specification, or for whatever reason was built with a code first approach, to their own devices in terms of generating a specification from existing code. The code found in the generator directory is one such device. It is highly, experimental, and subject to change.

Contributing

The /v1/openapi.yaml specification file is a generated file that should not be edited manually.

This video contains an overview of how to contribute endpoint configurations. The slide deck for this video can be found here.

The README file in the generator directory contains a detailed technical overview of the generator package as well as instructions on how to contribute to that package.

Client and API packages are not officially supported packages

The clients and v1 packages found in this repository are not officially supported packages.

Checklist for Updating For New Versions of Nomad

Updating to a new version of Nomad involves updating the spec generation code, and then running make to both create an updated v1/openapi.yml spec and generating the update clients.

  • Determine what changes will need to be made.
    • Find the go.mod file at the top of this repo to find the version of Nomad this repo is currently pinned to.
    • Go to your local checkout of Nomad OSS and find the differences in the api package between the version you intend to release and the version pinned in this repo. For example, to find the differences changes made between 1.3.5 and the 1.4.0-beta.1, run git diff v1.3.5..v1.4.0-beta.1 ./api.
  • In this repo, create a new branch update-nomad-vX.Y.Z
  • Update go.mod to the released version of Nomad.
  • Run go mod tidy.
  • Make a commit for updating the version of Nomad: git commit -am "update Nomad to vX.Y.Z"
  • Find the generator/*.go files that correspond to each API endpoint change you found above. For example, if the git diff found changes to api/acl.go you'll need to edit generator/acl.go.
  • Make the appropriate changes.
    • If you are adding new fields, edit the endpoints in place.
    • If you are adding new endpoints, start by copying this snippet: ./snippets/generator-endpoint.txt. Write the new endpoint by hand in the generator snippet. Refer to the slideshow above.
  • Make a commit with the spec generator update: git commit -am "update spec generator"
  • Run make v1 to update all the clients with that spec. Note: You will need Docker installed and running to update the clients.
  • Make a commit with all the client updates: git commit -am "update all clients"
  • Open a PR in this repo, targeting the main branch.