proper way to check for request method in nginx_lua

Question

I am trying to write a REST interface using nginx and lua. What I'd like to know is, what is the best way to check for the request method? If it's a GET, I need to query a db. If it's a POST or DELETE, I need to run another lua script to update the database. So far, this is what my code looks like to test what the request method is: ``` #curl -i -X GET 'http://localhost/widgets/widget?name=testname&loc=20000' -H "Accept:application/json" location /widgets/widget { default_type "text/pain"; #ifisEvil... unless done inside lua content_by_lua ' ngx.say("request is:",ngx.var.request_method) ngx.say("the constant is:",ngx.HTTP_GET) --ngx.say("the type is: ", type(ngx.HTTP_GET) if ngx.var.request_method == ngx.HTTP_GET then local args = ngx.req.get_uri_args() for key, val in pairs(args) do if type(val) == "table" then ngx.say(key, ": ", table.concat(val, ", ")) else ngx.say(key, ": ", val) end end end '; } ``` The output looks like this: ``` mytestdevbox2:/var/www/nsps2# curl -i -X GET 'htt…

Accepted Answer

Lua's method constants, such as `ngx.HTTP_GET`, are according to their documentation, mainly for `ngx.location*` calls.

So there is no "better" way of checking your method in Lua than comparing it with `GET` and the rest of the method strings.

However I would seriously consider using the "evil" `if` to split your requests based on method on nginx level.

This gives you the benefit of allowing you to configure separate logging, error handling etc. per method.

proper way to check for request method in nginx_lua

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