Return 413 HTTP status for S3 uploads if max upload limit is reached

See merge request gitlab-org/gitlab-workhorse!655

[ci skip]

Add metric image upload route for acceleration

See merge request gitlab-org/gitlab-workhorse!653

Add spec

Enable Secret Detection in CI NO CHANGELOG

See merge request gitlab-org/gitlab-workhorse!654

Add success-client-cache status for image scaler

See merge request gitlab-org/gitlab-workhorse!656

Since we weren't counting cached responses as successes, in Prometheus there were showing up as `unknown`, which contributes to the overall error budget.

We need to follow up with a runbook change that also counts cached responses as successes.

When an upload (e.g. a CI artifact) reaches the maximum file size limit,
uploads via S3 would return a 500 error to the user. This made it
difficult to understand why the upload failed.

This was happening because the `hardLimitReader` was aborting the
transfer with `ErrEntityTooLarge`, but this error was wrapped in layers
of AWS errors. Since none of these AWS errors were understood by the
file handler, a 500 error was returned.

To fix this, AWS has a way to retrieve the original error. We now
recursively go down the error stack to find the root cause.

Note that there is an open issue in the AWS SDK to make this easier with
Golang (https://github.com/aws/aws-sdk-go/issues/2820).

to help detect accidental exposure of secrets such
as API tokens and cryptographic keys in commits.

[ci skip]

Implement conditional GETs for image resizer

See merge request gitlab-org/gitlab-workhorse!647

We now set a `Last-Modified` header based on either local
file timestamps or the respective header returned from an
object storage provider.

Use detected file format for image scaler

See merge request gitlab-org/gitlab-workhorse!651

Make decisions based on what Go's `image.DecodeConfig`
tells us the image format actually is
instead of using the data sent from Rails app.

Rework image scaler tests

See merge request gitlab-org/gitlab-workhorse!650

We all test this in the module now

jaeger: limit operation cardinality by using route regex

See merge request gitlab-org/gitlab-workhorse!648

Update release steps - NO CHANGELOG

See merge request gitlab-org/gitlab-workhorse!645

Now mentions that the gitlab repo also needs to be updated
for the version to be deployed to .com.

Document  workhorse mission and how to add new features - NO CHANGELOG

See merge request gitlab-org/gitlab-workhorse!637

Our markdown processor do not allow embedding videos.

Update raven-go and gocertifi packages

See merge request gitlab-org/gitlab-workhorse!644

Adjust image scaler latency buckets

See merge request gitlab-org/gitlab-workhorse!643

These looked misaligned. According to production logs, we currently serve 99% of all those requests in less than 200ms.

The updated gocertifi package has a properly-recognized LICENSE file for
the license_finder gem.

raven-go has minor changes:
https://github.com/getsentry/raven-go/compare/v0.1.0..v0.2.0

[ci skip]

Remove unnecessary config struct pointers NO CHANGELOG

See merge request gitlab-org/gitlab-workhorse!642

Add a metric that tracks max image scaler processes

See merge request gitlab-org/gitlab-workhorse!640

Exclude dot-files from being linted

See merge request gitlab-org/gitlab-workhorse!641

This was matching `.go` files in my local `.git` folder.

Let's just exclude all hidden files.

This will allow us to compute a saturation metric to see
how close we are to exhausting this `actual / max`.

Refs https://gitlab.com/gitlab-com/runbooks/-/issues/52

Add a total-requests metric for the image scaler

See merge request gitlab-org/gitlab-workhorse!638