(CLI): show the time it takes for `cdk deploy` (including when running `cdk watch`) to finish

[skinny85]

Description

Let's print out the total time it takes for cdk deploy to finish, including when a deployment happens through cdk watch.

This will allows us to brag more easily about how quickly hotswapping works 😃.

Use Case

Showing the speedup hotswap deployments offer.

Proposed Solution

Print out the time it takes for deployment to finish in the CDK CLI.

Other information

Print out the total time

Acknowledge

• I may be able to implement this feature request
• This feature might incur a breaking change

[kaizencc]

I actually feel like this is reinventing the wheel a little bit, specifically for cdk deploy. We can easily call yarn cdk deploy or time cdk deploy to get the same functionality. The only time where we can't do this is for cdk watch, since it's not one-shot.

I thought we might just do this for cdk watch only and add a time stamp wrapper around this:

aws-cdk/packages/aws-cdk/lib/cdk-toolkit.ts

Line 302 in dee732d

await this.invokeDeployFromWatch(options);

Happy to do it for cdk deploy if you feel otherwise but I feel like the use case is only for cdk watch.

[skinny85]

I agree it's not great if we simply write out the total time. So why don't we spice things up a little bit? 😃

What if we divided the different phases of deploy, and printed out the time for each of them? For example, the time to synth the Cloud Assembly immediately jumps out to me as being interesting.

So, the output would be something like:

$ cdk deploy MyExampleStack
Stack MyExampleStack
...

✨  Synthesis time: 3.54s
...

✨  Deployment time: 4.56s
...

✨  Total time: 8.1s
...

Thoughts on this idea?

[misterjoshua]

In this vein: I'd appreciate a performance tracing mode for synthesis because I find it difficult to tell which parts of my cdk app (probably bundling assets, but which?) are slowing my synth down.