nodemcu_http_server : Minimalistic HTTP server for NodeMCU

Features

Serving static files from NodeMCU file system
Support for gzipped static files
Basic templates support (variable expansion)
Common layout
Redirects
Custom error pages

Basic usage example

dofile("server.lua")

print("Setting up WIFI...")
wifi.setmode(wifi.STATION)
wifi.sta.config("MY_SSID","MY_PASS")
wifi.sta.connect()

-- Start HTTP server on port 80
server(80, function(method, path, params, client_ip)
  if path == "/" then
    local html = interpolate_string("<h1>Your ip is ${ip}</h1>", {ip = client_ip})
    return 200, html, "text/html"
  end
  return 404
end)

tmr.alarm(1, 1000, tmr.ALARM_AUTO, function() 
  if wifi.sta.getip() == nil then 
    print("Waiting for IP ...") 
  else 
    print("IP is " .. wifi.sta.getip())
    tmr.stop(1)
  end
end)

HTTP requests are handled by user-provided function that receives the following arguments:

method - HTTP request verb (i.e. GET)
path - request path (i.e. /abc )
params - table containing parameters from request string (parsing of post request parameters is not yet supported)
client_ip - client IP address

Handler function returns the following values:

HTTP result code (i.e. 200)
Response body OR redirect URL for 3xx codes (not needed for error responses)
Content type (optional, defaults to "text/html")

Serving static files

If "/static/" prefix is detected in request path, serving static file is attempted. Slashes in request path are converted to underscores to get appropriate file name. E.g. for request path "/static/foo/bar.css" file "_static_foo_bar.css" will be served.

Static files may be gzipped to reduce used filesystem space. For a static file gzipped version is searched for first, i.e. for request path "/static/foo/bar.css" the server will first look for "_static_foo_bar.css.gz" and only then for "_static_foo_bar.css".

Server tries to guess content types for the most common file extensions used; see function guess_content_type() for details.

Layout and basic templating

If a file named "layout.html" is found, then it is used as a layout for all HTML responses returned by user callback function. Layout is only applied to responses with code 200 and content type "text/html".

Layout should contain "${content}" string which is replaced by actual response.

User callback function may use interpolate_string(string, table) and interpolate_file(filename, table) helper functions for variable expansion. The string or file contents (depending on the function used) is searched for strings like "${table_key}" which are replaced by respective values from the table.

Redirects

If the callback function returns a 3xx status code then the content returned is treated as redirect url (and returned in Location header)

Custom error pages

For custom error pages create respective html files - e.g. 404.html for 404 status code. If such a file exists - it will be served instead of standard error page. Layout (layout.html) is NOT applied to error pages.

borischernov / nodemcu_http_server