WiFi for everything #3 - HTTP Server

Time did not stop. I keep going with the development of my ESP8266 WiFi module's C library. I have now a very well working own HTTP server layer with lots of capabilities. Let's check out my test application.

The PIC32MX250F128B 32-bit microcontroller is hosting a simple webpage, which can be accessed using a regular internet browser. So there is no need for specific app. Before reaching the content above the user have to enter a username and password pair. This HTTP Basic Authentication was implemented most recently.

Table cells on the page are representing relays connected to the microcontroller, which can be turned on and off by clicking on them. This function is performed "under the hood" using an AJAX request. The response is an XML resource including the actual state of the relays (color codes :D ).

The main feature of my HTTP server implementation is the support of dynamic resources. By this test application the index.html resource is static, because it's content is constant. The XML state resource is dynamic and has parts where text strings will be inserted. These strings are generated at runtime. The mechanism is similar to the Microchip's HTTP2 server solution, but in my realization the resources are handled by the library standalone.

The way I put HTTP resources (files) to the project is using my dotNet app called "HttpContent2WifiServer".

It creates .h header file, which is included to the project. This header contains the file as char array and a structure with important parameters (name, size, number of chunks, properties, positions of the dynamic strings, names of the functions printing dyn. strings, etc.).

Header file below was created from the file states.xml. "~{...}" marks are containing the references to the print functions (Http_Print_xxxxx). These tags are eliminated from the generated array, but their positions are stored (function parameters also).

Header file of a static resource looks a way more simple:

Using my dotNet app makes the development more comfortable and faster.

"TCP Socket Connected" indicator for sockets 0-4

In the next article we will see my first really useful application of this Internet of Things stuff... :)