Using default headers if user has not declared them.

[zastrixarundell]

Based on issue #69 (nice).

Pull request where the user can write headers before the connection. If the user does not write some required headers like Origin it will use the default hard-coded headers, if the user does write them they they are used rather than the hard-coded ones.

This is only implemented for the following headers:

• Upgrade
• Connection
• Sec-WebSocket-Version
• User-Agent
• Origin

Has been tested on an ESP8266. The server for websockets was an Elixir Phoenix one but it doesn't really matter what is the websocket server language.

[gilmaimon]

Hi! Thanks for helping out with this issue. The code looks good, there are few points I'd like you to change:

1. I prefer that every if has a {...} block after it (instead of one-liner ifs)
2. Arguments should be const and passed-by-ref when possible, please fix keywordDoesNotExist according to this rule.
3. Is there really a need for the duplication in usedKeys? Can you modify the code such that keywordDoesNotExist will look in customHeaders to check if the key exists?
4. keywordDoesNotExist is a cool name, but how about shouldAddDefaultHeader?

Thank you again, awesome job!

[zastrixarundell]

Yeah it won't be an issue at all, I'll update it and push it in a min.

[zastrixarundell]

Oh and I'm cool with everything except the 4th one because IMHO that name is counter-intuitive when used with the 3rd (task?):

            if (keywordDoesNotExist(usedKeys, header.first)) {
                usedKeys.push_back(header.first);
            }

VS

            if (shouldAddDefaultHeader(usedKeys, header.first)) {
                usedKeys.push_back(header.first);
            }

I mean you just say if you want to keep it I'll keep it and if not I'll change it, no problem.

[gilmaimon]

Because usedKeys is not actually needed, I imagine the code could look like this:

if (shouldAddDefaultHeader("Origin", customHeaders)) {
    // add default Origin
}

You could give it another fitting name, but the important point is that usedKeys is not needed in my opinion because that info is already in customHeaders.

[zastrixarundell]

Ah I see now what you meant. I'll update the code.

[zastrixarundell]

Not sure whether I have to directly say but: The deed has been done. Tested on 2 different ESP8266's and worked correctly.

[gilmaimon]

Looks good! I assume you tested this and it is working fine. Merged :)

Thank you!