Import this test as "Runscope API Test" to your Runscope account to get a quick start on updating shared environment variables. For more information: https://blog.runscope.com/posts/how-to-use-subtest-steps-to-handle-oauth2-access-tokens-runscope-api

runscope-api-refresh-access-token-template.json

{
  "trigger_url": "https://api.runscope.com/radar/2e9ff15c-ef6d-46b2-9815-65f05812e02e/trigger", 
  "name": "Refresh Access Token Template", 
  "version": "1.0", 
  "exported_at": 1483638296, 
  "steps": [
    {
      "url": "https://yourapihere.com?dummyNewToken=theNewGeneratedToken", 
      "variables": [
        {
          "source": "response_json", 
          "property": "args.dummyNewToken", 
          "name": "newAccessToken"
        }
      ], 
      "step_type": "request", 
      "auth": {}, 
      "note": "Get New Token (sample)", 
      "headers": {}, 
      "assertions": [
        {
          "comparison": "equal_number", 
          "value": 200, 
          "source": "response_status"
        }
      ], 
      "scripts": [], 
      "before_scripts": [], 
      "method": "GET"
    }, 
    {
      "url": "https://api.runscope.com/buckets/{{runscope_bucket}}/environments/{{shared_environment}}", 
      "variables": [
        {
          "source": "response_json", 
          "property": "data", 
          "name": "envSettings"
        }
      ], 
      "step_type": "request", 
      "auth": {}, 
      "fragment": "", 
      "note": "Get Shared Environment Configuration", 
      "headers": {
        "Authorization": "Bearer {{runscope_token}}"
      }, 
      "assertions": [
        {
          "comparison": "equal_number", 
          "value": 200, 
          "source": "response_status"
        }
      ], 
      "scripts": [], 
      "before_scripts": [], 
      "method": "GET"
    }, 
    {
      "body": "", 
      "form": {}, 
      "url": "https://api.runscope.com/buckets/{{runscope_bucket}}/environments/{{shared_environment}}", 
      "variables": [], 
      "step_type": "request", 
      "auth": {}, 
      "fragment": "", 
      "note": "Update Shared Environment Configuration", 
      "headers": {
        "Authorization": "Bearer {{runscope_token}}"
      }, 
      "assertions": [
        {
          "comparison": "equal_number", 
          "value": 200, 
          "source": "response_status"
        }
      ], 
      "scripts": [], 
      "before_scripts": [
        "var envSettings = JSON.parse(variables.get(\"envSettings\"));\nenvSettings.initial_variables.accessToken = variables.get(\"newAccessToken\");\nrequest.body = JSON.stringify(envSettings);"
      ], 
      "method": "PUT"
    }
  ], 
  "description": ""
}