index.ts

import * as aws from "@pulumi/aws";
import { all } from "@pulumi/pulumi";

async function main(): Promise<any> {
    const ami = await aws.getAmi({
        nameRegex: "ubuntu/images/hvm-ssd/ubuntu-bionic-18.04-amd64-server-*",
        mostRecent: true,
        owners: ["099720109477"],
    });

    const vpc = await aws.ec2.getVpc({
        default: true,
    });
    const subnetIds = await aws.ec2.getSubnetIds({
        vpcId: vpc.id,
    });

    const serverSecurityGroup = new aws.ec2.SecurityGroup(`repro-security-group`, {
        description: "ASG Repro SG",
        ingress: [sgRule("Ingress")],
        egress: [sgRule("Egress")],
    });

    const launchConfiguration = new aws.ec2.LaunchConfiguration(`repro-launch-config`, {
        associatePublicIpAddress: false,
        instanceType: aws.ec2.T2InstanceMicro,
        imageId: ami.id,
        securityGroups: [serverSecurityGroup.id],
    });

    // These are throwaway values but demonstrate the problem OK
    const tagSet = all([ami.id, serverSecurityGroup.id])
        .apply(([amiId, secGroupId]) => [
            {
                key: "AMI",
                value: amiId,
                propagateAtLaunch: true,
            },
            {
                key: "SecGroup",
                value: secGroupId,
                propagateAtLaunch: false,
            },
        ]);

    new aws.autoscaling.Group(`repro-autoscaling-group`, {
        desiredCapacity: 0,
        minSize: 0,
        maxSize: 1,

        launchConfiguration: launchConfiguration.id,
        vpcZoneIdentifiers: subnetIds.ids,

        tags: tagSet,
    });
}

function sgRule(name: string): any {
    return {
        description: `All ${name} Traffic`,
        fromPort: 0,
        toPort: 0,
        protocol: "-1",
        cidrBlocks: ["0.0.0.0/0"],
    };
}

const _ = main();

output.shell

❯ pulumi version
v0.14.3

❯ pulumi preview
Previewing update of stack 'pulumi-asg-repro-2-dev'
Previewing changes:

     Type                            Name                                       Plan          Info
 +   pulumi:pulumi:Stack             pulumi-asg-repro-2-pulumi-asg-repro-2-dev  create        1 error
 +   ├─ aws:ec2:SecurityGroup        repro-security-group                       create
 +   ├─ aws:ec2:LaunchConfiguration  repro-launch-config                        create
 *   └─ global                       global                                     no change     3 errors

Diagnostics:
  pulumi:pulumi:Stack: pulumi-asg-repro-2-pulumi-asg-repro-2-dev
    error: One or more resource validation errors occurred; refusing to proceed

  global: global
    error: aws:autoscaling/group:Group resource 'repro-autoscaling-group' has a problem: "tag.0.key": required field is not set

    error: aws:autoscaling/group:Group resource 'repro-autoscaling-group' has a problem: "tag.0.value": required field is not set

    error: aws:autoscaling/group:Group resource 'repro-autoscaling-group' has a problem: "tag.0.propagate_at_launch": required field is not set

error: an error occurred while advancing the preview

package.json

{
	"name": "pulumi-asg-repro-2",
	"main": "bin/index.js",
	"typings": "bin/index.d.ts",
	"scripts": {
		"build": "tsc"
	},
	"devDependencies": {
		"typescript": "^2.7.2",
		"@types/node": "latest"
	},
	"dependencies": {
		"@pulumi/pulumi": "latest",
		"@pulumi/aws": "^0.14.6-dev-1533615635-g36bed34"
	}
}