Metadata JSON hits HTTP header-size limit

[adamhooper]

When uploading files with large metadata-json, we can hit a Netty maxHeaderSize limit.

With non-ASCII characters, we can hit 8kb awfully fast: each non-ASCII character is encoded as \uXXXX: 6-12 ASCII characters. Our metadata JSON limit is effectively 1.3kb.

Unfortunately, setting play.server.netty.maxHeaderSize in config did nothing for me in dev mode. I'm perplexed.

But it's ultimately moot: Play 2.6 uses akka-http, which will have its own config option.

[adamhooper]

Quoting http://doc.akka.io/docs/akka-http/10.0.9/scala/http/configuration.html:

    # The limits for the various parts of the HTTP message parser.
    max-uri-length             = 2k
    max-method-length          = 16
    max-response-reason-length = 64
    max-header-name-length     = 64
    max-header-value-length    = 8k
    max-header-count           = 64
    max-chunk-ext-length       = 256
    max-chunk-size             = 1m

Indeed, we uploaded a large docset with no problem. I believe this is solved.

[adamhooper]

(The difference is: we're using Play 2.6 now.)