IonoWeb

This library provides functions to control and monitor iono ethernet via a HTTP-based API.

The library provides the following methods:

begin

IonoWeb.begin(int port)

Start the Web server on the specified port number.

processRequest

IonoWeb.processRequest()

This method must be called periodically (inside the loop() function) in order to serve the incoming HTTP requests.

subscribe

IonoWeb.subscribe(unsigned long stableTime, float minVariation, char *host, int port, char *command, uint8_t mode1, uint8_t mode2, uint8_t mode3, uint8_t mode4)

This method can be used to enable push notifications to monitor iono's state: iono will trigger a HTTP request to a remote host whenever a pin changes state.
After calling this method, every time a pin changes state and it is stable for a time equal to stableTime (in milliseconds), iono will perform a HTTP request to the specified port of the specified host. For inputs read as voltage or current the call will be triggered only if the value changes of more than minVariation.
The parameters mode1...mode4 specify how to read input 1 ... 4: a value of '1' means read as digital (i.e. DI1...DI4), '2' means read as voltage (i.e. AV1...AV4) and '3' means read as current (i.e. AI1...AI4).

The HTTP request will have the following format:

http://<host>:<port><command>?<pin>=<val>

For instance, after calling:

IonoWeb.subscribe(100, 0.1, "192.168.0.200", 8080, "/bar", 1, 1, 2, 3);

if input DI1 goes high and stays high for 100ms, iono will perform a HTTP request equivalent to this:

http://192.168.0.200:8080/bar?DI1=1

if the voltage on AV3 changes of a value greater or equal to 0.1V (e.g. from 5.3V to 5.4V), iono will perform a HTTP request equivalent to this:

http://192.168.0.200:8080/bar?AV3=5.40

## HTTP API The HTTP API provides for the following three actions:

/api/state

Making a HTTP request to this path, like the following:

http://192.168.0.100/api/state

will return a JSON object with the following format:

{
    "DO1": <do1_val>,
    "DO2": <do2_val>,
    "DO3": <do3_val>,
    "DO4": <do4_val>,
    "DO5": <do5_val>,
    "DO6": <do6_val>,
    "I1": {
        "D": <di1_val>,
        "V": <av1_val>,
        "I": <ai1_val>
    },
    "I2": {
        "D": <di2_val>,
        "V": <av2_val>,
        "I": <ai2_val>
    },
    "I3": {
        "D": <di3_val>,
        "V": <av3_val>,
        "I": <ai3_val>
    },
    "I4": {
        "D": <di4_val>,
        "V": <av4_val>,
        "I": <ai4_val>
    },
    "I5": {
        "D": <di5_val>
    },
    "I6": {
        "D": <di6_val>
    }
}

which reports the current value of iono's pins.

/api/set

An HTTP request to this path with a set of pairs <pin_name>=<val> as parameters can be used to control iono's outputs.
Here is a few examples:

http://192.168.0.100/api/set?DO1=1
http://192.168.0.100/api/set?DO1=0&DO4=f
http://192.168.0.100/api/set?DO1=0&DO2=1&DO3=0&DO4=1&DO5=0&DO6=0&AO1=7.3

For digital outputs the allowed values are '0' (low), '1' (high) or 'f' (flip the current state); for analog ones, the allowed values are floating numbers from 0.0 to 10.0.

/api/subscribe

This HTTP request must be used following this format:

http://192.168.0.100/api/subscribe?st=<time>&mv=<var>&host=<host>&port=<port>&cmd=<command>&mode1=<mode1>&mode2=[d|v|i]&mode3=[d|v|i]&mode4=[d|v|i]

The above request corresponds to a call to the following method:

IonoWeb.subscribe(<time>, <var>, <host>, <port>, <command>, <mode1>, <mode2>, <mode3>, <mode4>);

where <mode1>...<mode4> are set to '1', '2' or '3' if the corresponding parameters are respectively set to 'd', 'v' or 'i'

For instance, this request:

http://192.168.1.243/api/subscribe?mv=0.1&st=100&host=192.168.0.200&port=8080&cmd=/bar&mode1=d&mode2=d&mode3=v&mode4=i

corresponds to a call to:

IonoWeb.subscribe(100, 0.1, "192.168.0.200", 8080, "/bar", 1, 1, 2, 3);

The response will contain a JSON object with the current state as in /api/state.

The subscription will timeout after 60 seconds, so it must be renewed periodically.

Examples

The library folder includes some examples that can be opened directly from the Arduino IDE menu File > Examples > IonoWeb.

• API shows how to use the HTTP API;
• SubscribeWeb shows how to use the subscribe methods to monitor inputs;
• WebApp implements a complete Web application to control, monitor and configure iono. See next paragraph for more details.

WebApp

To access the Web interface provided by this sketch, open a browser and go to http://192.168.0.100/

The six switches DO1 ... DO6 control the corresponding iono's relays; the table shows the current state of its inputs and the AO1 field can be used to change the voltage of the analog output.

To access the configuration panel, click on the icon on the top-right corner. Here it will be possible to modify iono's configuration (IP, DNS, Gateway, Subnet, MAC address and password to access the Web interface).

Moreover, this sketch provides for a procedure to reset iono's configuration. To this end, power off iono, short-circuit pins RX and TX and power it back on. Now go to http://192.168.0.100/, set the new configuration and save, wait for the process to complete and remove the short-circuit.