k6 environmental variables results in GO error "invalid character" - k6

Question

k6 docs make using environmental variables very simple and I tried following their instructions, but I get a GO error when I try to run it:
ERRO[0000] GoError: parse https://${__ENV.TARGET_ENV}-api.mycompany.com/v1/managers/259999/properties": invalid character "{" in host name".
I don't see an extra bracket anywhere. This script was working fine when I had the url as https://green-api.mycompany.com/v1/managers/259999/properties. Am I possibly missing an import or dependency somewhere? All I am trying to do is get it working to where when i type k6 run --env TARGET_ENV=green propertiesScript.js, it executes against http://green-api.mycompany.com/v1/managers/259999/properties. Here is the file:
import { check } from "k6";
export let options = {
thresholds: {
http_req_duration: ["p(90)<300"], // 95% of requests should be below 200ms
Errors: ["count<100"],
},
};
export default function () {
var url =
"https://${__ENV.TARGET_ENV}-api.mycompany.com/v1/managers/259999/properties";
const params = {
headers: {
"X-App-Token": "<our app token>",
"X-Auth-Token":
"<our auth token>",
accept: "application/json",
},
};
let res = http.get(url, params);
console.log(res.body);
console.log(JSON.stringify(res.headers));
check(res, {
"status is 200": (r) => r.status === 200,
});
}
I also tried adding scenarios and adjusting the body of my file. These are the scenarios:
thresholds: {
http_req_duration: ["p(90)<300"], // 95% of requests should be below 200ms
Errors: ["count<100"],
},
scenarios: {
pod_green: {
tags: { my_custom_tag: "green" },
env: { MYVAR: "green" },
executor: "shared-iterations",
},
pod_red: {
tags: { my_custom_tag: "red" },
env: { MYVAR: "red" },
executor: "shared-iterations",
},
staging: {
tags: { my_custom_tag: "staging" },
env: { MYVAR: "staging" },
executor: "shared-iterations",
},
},
};
Then I edited my export default function and I was able to get that script to run, but it runs against every single environment.

Answer 1

You need to use backticks when you set the url variable for string interpolation to work in template literals. See the documentation.
So in your case you should have:
var url =
`https://${__ENV.TARGET_ENV}-api.mycompany.com/v1/managers/259999/properties`;