Bad signature value triggers uncaught exception

[karpet]

If you POST a signature value that is not a valid base64-encoded image string, you must wait for the server to timeout (30s) and this error is thrown:

Serverless: ANY /vr/en (λ: hello)
{ Error: Command failed: convert: improper image header /tmp/signature.png' @ error/png.c/ReadPNGImage/4232. convert: no images defined /tmp/signature.png' @ error/convert.c/ConvertImageCommand/3275.

at ChildProcess.onExit (/Users/karpet/work/ksvotes.org/NVRIS/node_modules/gm/lib/command.js:301:17)
at ChildProcess.emit (events.js:182:13)
at ChildProcess.EventEmitter.emit (domain.js:442:20)
at maybeClose (internal/child_process.js:957:16)
at Process.ChildProcess._handle.onexit (internal/child_process.js:246:5) code: 1, signal: null }

(node:66136) UnhandledPromiseRejectionWarning: Error: Command failed: convert: improper image header /tmp/signature.png' @ error/png.c/ReadPNGImage/4232. convert: no images defined /tmp/signature.png' @ error/convert.c/ConvertImageCommand/3275.

at ChildProcess.onExit (/Users/karpet/work/ksvotes.org/NVRIS/node_modules/gm/lib/command.js:301:17)
at ChildProcess.emit (events.js:182:13)
at ChildProcess.EventEmitter.emit (domain.js:442:20)
at maybeClose (internal/child_process.js:957:16)
at Process.ChildProcess._handle.onexit (internal/child_process.js:246:5)

(node:66136) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 17)
Serverless: Replying timeout after 30000ms

[jakelowen]

I agree. I started to implement this but realized I was violating some DRY.

I have just pushed (and deployed to dev) a refactor which abstracts out the duplicative route processing logic. This means we should be able to implement proper try / catch blocks in helpers/routeLogic.

routeLogic should return an object which will be passed along as JSON as an API response.