landru29 / metrics_i2c

Push Data to OVH metrics timeseries (via I2C)

Prerequisite

• Have a WEMOS D1 Mini
• Have a sane installation of Arduino IDE
• Have WEMOS toolkit installed (https://github.com/esp8266/Arduino)

Hardware

• Wemos D1 Mini
• Other arduino (for master)

Arduino

• Create a file config.h based on config.h.sample
• Compile program

config.h

The file shold contain the following definition:

#define TOKEN "put the 'write' token in graphana topic in the manager"

#define OPENTSDB_HOST "the host of your metrics plateform (ie 'opentsdb.gra1.metrics.ovh.net')"

#define WARP10_HOST "the host of your metrics plateform (ie 'warp10.gra1.metrics.ovh.net')"

#define FINGERPRINT "XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX XX"

The token is the write token you created in the OVH manager (Cloud > metrics): https://www.ovh.com/manager/cloud/#/

Fingerprint

in http.cpp, you must check to have the correct fingerprint:

echo | openssl s_client -showcerts -servername opentsdb.gra1.metrics.ovh.net -connect opentsdb.gra1.metrics.ovh.net:443 2>/dev/null | openssl x509 -noout -fingerprint -sha1 -inform pem | sed -e "s/.*=//g" | sed -e "s/\:/ /g"

VSCode

Install Arduino extension

Create file .vscode/c_cpp_properties.json

{
    "configurations": [
        {
            "name": "Linux",
            "includePath": [
                "${env:HOME}/Arduino/hardware/esp8266com/esp8266/variants/d1_mini",
                "${env:HOME}/Arduino/hardware/esp8266com/esp8266/**",
                "${env:HOME}/.arduino15/packages/esp8266/hardware/esp8266/2.5.2/libraries/**",
                "${env:HOME}/Arduino/libraries/**",
            ],
            "forcedInclude": [],
            "intelliSenseMode": "gcc-x64",
            "compilerPath": "/usr/bin/gcc",
            "cStandard": "c11",
            "cppStandard": "c++17"
        }
    ],
    "version": 4
}

Create file .vscode/arduino.json

{
    "board": "esp8266com:esp8266:d1_mini",
    "configuration": "xtal=80,vt=flash,exception=legacy,ssl=all,eesz=4M2M,ip=lm2f,dbg=Disabled,lvl=None____,wipe=none,baud=921600",
    "sketch": "four_a_pain_metrics.ino",
    "port": "/dev/ttyUSB0"
}

Slave

Wemos will be the slave. Compile the program and load it in the Wemos. Connect I2C to Master:

• Clock: D1
• Data: D2

Master

Include communication.h in your code. In your setup, just put:

Wire.begin()

Then you can use the class MetricsClient

Do not forget to connect I2C to the slave:

• Clock: A5
• Data: A4