Kevin Leimkuhler 5d7662fd90 Update web server to use tap APIService (#3208) ... ### Motivation PR #3167 introduced the tap APIService and migrated `linkerd tap` to use it. Subsequent PRs (#3186 and #3187) updated `linkerd top` and `linkerd profile --tap` to use the tap APIService. This PR moves the web's Go server to now also use the tap APIService instead of the public API. It also ensures an error banner is shown to the user when unauthorized taps fail via `linkerd top` command in *Overview* and *Top*, and `linkerd tap` command in *Tap*. ### Details The majority of these changes are focused around piping through the HTTP error that occurs and making sure the error banner generated displays the error message explaining to view the tap RBAC docs. `httpError` is now public (`HTTPError`) and the error message generated is short enough to fit in a control frame (explained [here](https://github.com/linkerd/linkerd2/blob/kleimkuhler%2Fweb-tap-apiserver/web/srv/api_handlers.go#L173-L175)). ### Testing The error we are testing for only occurs when the linkerd-web service account is not authorzied to tap resources. Unforutnately that is not the case on Docker For Mac (assuming that is what you use locally), so you'll need to test on a different cluster. I chose a GKE cluster made through the GKE console--not made through cluster-utils because it adds cluster-admin. Checkout the branch locally and `bin/docker-build` or `ares-build` if you have it setup. It should produce a linkerd with the version `git-04e61786`. I have already pushed the dependent components, so you won't need to `bin/docker-push git-04e61786`. Install linkerd on this GKE cluster and try to run `tap` or `top` commands via the web. You should see the following errors: ### Tap  ### Top  Signed-off-by: Kevin Leimkuhler <kleimkuhler@icloud.com>		2019-08-08 10:18:32 -07:00
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components	Update web server to use tap APIService (#3208)	2019-08-08 10:18:32 -07:00
index.js	Remove unimplemented debug page on dashboard (#2952)	2019-06-17 14:43:09 -05:00