I was just tinkering with Pulumi at the Node REPL and I ran into a couple discouraging issues. Is using the Pulumi JavaScript SDK in an interactive context —i.e., a console/REPL— an unsupported use case, or is it perhaps just not a priority? (Details follow; I wanted to put the TLDR up top 🙂) I’m using Pulumi 0.16.7 on macOS 10.14.2 and NodeJS 11.4.0, with both Pulumi and Node installed via Homebrew. I created a fresh project and stack with

pulumi new aws-javascript

and successfully previewed the changes. My original motivation for this was to experiment with calling the

getAmi

function to view some example result data, as well as its error behavior. My first attempt:

$ node
> const aws = require("@pulumi/aws");
{ Error: Missing required configuration variable 'aws:region'
	please set a value using the command `pulumi config set aws:region <value>`
    at Object.requireWithDefault (/Users/jtilles/Developer/Scratch/pulumi-experiment/node_modules/@pulumi/utilities.ts:45:16)
    at exports.region.utilities.requireWithDefault (/Users/jtilles/Developer/Scratch/pulumi-experiment/node_modules/@pulumi/config/vars.ts:44:78)
    at Config.require (/Users/jtilles/Developer/Scratch/pulumi-experiment/node_modules/@pulumi/pulumi/config.js:141:19) __pulumiRunError: true, key: 'aws:region' }

After some digging into Pulumi’s source code, I eventually figured out that I needed to export

PULUMI_CONFIG='{"aws:config:region":"us-east-1"}'

. I progressed to a new error!

$ PULUMI_CONFIG='{"aws:config:region":"us-east-1"}' node
> const aws = require("@pulumi/aws");
undefined
> aws.getAmi({owners: ["amazon"], filters: [{name: "name", values: ["amzn2-ami-hvm-2.*-x86_64.gp2"]}], mostRecent: true})
Promise {
  <pending>,
  domain:
   Domain {
     domain: null,
     _events:
      [Object: null prototype] {
        removeListener: [Function: updateExceptionCapture],
        newListener: [Function: updateExceptionCapture],
        error: [Function: debugDomainError] },
     _eventsCount: 3,
     _maxListeners: undefined,
     members: [] } }
> (node:15240) UnhandledPromiseRejectionWarning: Error: Pulumi program not connected to the engine -- are you running with the `pulumi` CLI?
    at Object.getMonitor (/Users/jtilles/Developer/Scratch/pulumi-experiment/node_modules/@pulumi/pulumi/runtime/settings.js:87:19)
    at Object.<anonymous> (/Users/jtilles/Developer/Scratch/pulumi-experiment/node_modules/@pulumi/pulumi/runtime/invoke.js:51:40)
    at Generator.next (<anonymous>)
    at fulfilled (/Users/jtilles/Developer/Scratch/pulumi-experiment/node_modules/@pulumi/pulumi/runtime/invoke.js:17:58)
    at process.internalTickCallback (internal/process/next_tick.js:77:7)
(node:15240) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:15240) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Since the second error didn’t look particularly debuggable (from the looks of it, I’m guessing I would need to launch a gRPC server in order to use the SDK from the REPL) I decided it was time to ask for help.