upgrade testing: add README and fix authorization header (#25059)

Add a README describing the setup required for running upgrade testing via
Enos. Also fix the authorization header of our `wget` to use the proper header
for short-lived tokens, and the output path variable of the artifactory step.

Co-authored-by: Juanadelacuesta <8647634+Juanadelacuesta@users.noreply.github.com>

enos/README.md

@@ -0,0 +1,111 @@
+# Upgrade Testing with Enos
+
+We're using [Enos](https://github.com/hashicorp/enos) to perform upgrade
+testing. These tests are run via GitHub Actions from the private `nomad-e2e`
+repository. This document describes how you can run these tests from your local
+development environment if you're a HashiCorp developer.
+
+There are two major components to be aware of:
+* This directory includes the upgrade scenario and the Terraform modules and
+  shell scripts needed to execute that scenario.
+* The scenario uses the same cluster provisioning infrastructure as the E2E
+  tests in the `e2e/` directory in the root of this repo. So to run the upgrade
+  scenario you also have to have all the credentials set up to run the E2E
+  tests. (We may try to fold these together in the future.)
+
+The `terraform/` folder has provisioning code to spin up a Nomad cluster on
+AWS. You'll need both Terraform and AWS credentials to setup AWS instances on
+which e2e tests will run. See the
+[README](https://github.com/hashicorp/nomad/blob/main/e2e/terraform/README.md)
+for details. The number of servers and clients is configurable, as is the
+specific build of Nomad to deploy and the configuration file for each client
+and server.
+
+## Setup
+
+You'll need a recent version of Terraform, the most current version of Enos, as
+well as AWS credentials to create the Nomad cluster and credentials for HCP. The
+Terraform configurations assume that an appropriate instance role has been
+configured elsewhere and that you have the ability to `AssumeRole` into the AWS
+account.
+
+Configure the following environment variables. For HashiCorp Nomad developers,
+this configuration can be found in 1Pass in the Nomad team's vault under
+`nomad-e2e`.
+
+```
+export HCP_CLIENT_ID=
+export HCP_CLIENT_SECRET=
+```
+
+The Vault admin token will expire after 6 hours. If you haven't created one
+already use the separate Terraform configuration found in the
+`$REPO/e2e/terraform/hcp-vault-auth` directory. The following will set the correct
+values for `VAULT_TOKEN`, `VAULT_ADDR`, and `VAULT_NAMESPACE`:
+
+```
+terraform init
+terraform apply --auto-approve
+$(terraform output --raw environment)
+```
+
+Make sure your AWS credentials have been refreshed with the appropriate IAM role:
+
+```
+$ doormat login --force
+$ doormat aws cred-file add-profile --role "$ROLE" --set-default
+```
+
+Next you'll need to obtain an Artifactory token via Doormat.
+
+```
+export ARTIFACTORY_TOKEN=$(doormat artifactory create-token | jq -r .access_token)
+```
+
+Next you'll need to populate the Enos variables file `enos.vars.hcl (unlike
+Terraform, Enos doesn't accept variables on the command line):
+
+```hcl
+artifactory_username = "<your email address>"
+artifactory_token    = "<your ARTIFACTORY_TOKEN from above>"
+product_version      = "1.8.9"                        # starting version
+upgrade_version      = "1.9.4"                        # version to upgrade to
+download_binary_path = "/home/foo/Downloads/nomad"    # directory on your machine to download binaries
+nomad_license        = "<your Nomad Enterprise license, when running Nomad ENT>"
+consul_license       = "<your Consul Enterprise license, currently always required>"
+aws_region           = "us-east-1"
+```
+
+When the variables file is placed in the enos root folder with the name 
+`enos.vars.hcl` it is automatically picked up by enos, if a different variables 
+files will be used, it can be pass using the flag `--var-file`.
+
+## Reviewing Enos
+
+You can quickly validate the Enos scenario configuration without running it:
+
+```
+$ enos scenario validate upgrade --var-file /tmp/enos.vars
+$ echo $?
+0
+```
+
+You can also review what Enos will do by generating an outline you can read in
+your browser:
+
+```
+$ enos scenario outline upgrade --var-file /tmp/enos.vars --format=html > /tmp/outline.html
+$ open /tmp/outline.html
+```
+
+## Running Enos
+
+Run the Enos scenario end-to-end:
+
+```
+$ enos scenario run upgrade --var-file /tmp/enos.vars --timeout 2h
+```
+
+Enos will not clean up after itself automatically if interrupted. If you have to
+interrupt it, you may need to run `enos scenario destroy upgrade --var-file
+/tmp/enos.vars `

enos/enos.vars.example.hcl

@@ -0,0 +1,11 @@
+# Copyright (c) HashiCorp, Inc.
+# SPDX-License-Identifier: BUSL-1.1
+
+artifactory_username = "<your email address>"
+artifactory_token    = "<your ARTIFACTORY_TOKEN from above>"
+product_version      = "1.8.9"                     # starting version
+upgrade_version      = "1.9.4"                     # version to upgrade to
+download_binary_path = "/home/foo/Downloads/nomad" # directory on your machine to download binaries
+nomad_license        = "<your Nomad Enterprise license, currently always required>"
+consul_license       = "<your Consul Enterprise license, currently always required>"
+aws_region           = "us-east-1"

enos/modules/fetch_artifactory/scripts/install.sh

@@ -4,7 +4,7 @@
 
 set -xeuo pipefail
 
-wget --header="X-JFrog-Art-Api:$TOKEN" -O "$LOCAL_ZIP" "$URL"
+wget --header="Authorization: Bearer $TOKEN" -O "$LOCAL_ZIP" "$URL"
 
 if [ $? -eq 0 ]; then
     echo "File downloaded successfully: $LOCAL_ZIP"