Instrument LambdaHandler's' convert_event function

[david-perez]

This would have come in handy when debugging #2676.

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• No codegen difference in the AWS SDK
• No codegen difference in the Client Test
• No codegen difference in the Server Test
• No codegen difference in the Server Test Python
• No codegen difference in the Server Test Typescript

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[hlbarber]

On second thought, the URI here could be sensitive. So perhaps we shouldn't log it?

[david-perez]

Let's change it so that the URI is logged only when the feature unredacted-logging is enabled.

[hlbarber]

Let's change it so that the URI is logged only when the feature unredacted-logging is enabled.

An alternative here is that we create a wrapper which is the union of all redactions that can be applied prior to routing. e.g. if operation A had path segment 0 sensitive and operation B had path segment 1 sensitive then prior to routing we redact both 0 and 1.

[david-perez]

That would be tricky to implement correctly; it wouldn't be as simple as maintaining a list of indices on sensitive path segments, since greedy labels can capture a different number of path segments each time.

[hlbarber]

since greedy labels can capture a different number of path segments each time

Isn't the join of two greedy labels the component wise min over the arguments segment_index, end_offset?

Looking over the API, I think this is doable without much hassle.

[david-perez]

Yes that would work. E.g. with the two patterns:

1. /prefix/{greedy1+}/suffix
2. /{greedy2+}/foo-bar-baz

where the greedy1 and greedy2 labels are bound to @sensitive shapes, we get a component wise minimum of:

GreedyLabel {
    segment_index: 0,
    end_of_offset: 7,
}

So upon receiving a request URI like /bound/to/greedy2/foo-bar-baz, we'd only be able to print something like /<redacted+>/<redacted>bar-baz, which is a bit weird.