my settings: python run_app.py --host=192.168.1.7 -p -t 10 -s 22

The graph is prettier, but now requires the user to also install plotly. (use "sudo pip install plotly" on rasberry pi)

damn_hot_pie_lite

Run the lite version using sudo ./run.sh it has the same settings as above, but does not run the server. The lite version only logs data to the database and generates an index.html page (which can then be loaded by apache, NGINX, or another webserver). I found it was simple just to copy all of the files to the /var/www/html folder. Make run.sh executable with sudo chmod u+x run.sh. You can setup a cron job or bash.rc to run the bash script at startup so you have minimal work to do, just boot and go to localhost!!

Raspberry Pi DHT sensor website app

This app lets you to view your DHT readouts online in a form of interactive plot.

Sample:

(Viewing this plot may require you to push the autoscale button on plot.)

Setup

• Raspberry PI
• DHT11 sensor (DHT22 and DHT2303 are also supported, also see wiring)
• interwebz connection
• Python 2.7
• Flask
• SQLAlchemy
• Adafruit DHT driver
• plotly

Dependencies

For web server and database dependencies requirements run:

sudo pip install -r requirements.txt

You will also need Adafruit Python DHT driver. The driver is accessible here: https://github.com/adafruit/Adafruit_Python_DHT Follow the installation instructions in the link above.

Installation

This projects runs purely as python app. As long as all the requirements are met, you don't have to install anything.

Running the project

If you are not interested in further options just run:

python run_app.py

Website will run defaultly on host 0.0.0.0 and port 8080.

Additional options of running and project files

model.py

This file contains sql model of the database where all sensor data will be saved. Running this script will result in creating file dht_database.db in folder where model.py is.

record_data.py and recording data to database

Contains class responsible for acquiring data input and saving it in database. Can be runned separately as script. If runned, will loop endlessly and save sensor data to database with given interval.

Usage: record_data.py [options]

Options:
  -h, --help  show this help message and exit
  -p          print every record to STDOUT [default: False]
  -t T        time interval in minutes to request readout from sensor
              [default: 15]
  --pin=PIN   data pin connected to sensor [default: 4]
  -s S        number of DHT sensor in use (supported: 11, 22, 2302) [default:
              11]

server.py, template/index.html and the web service

server.py contains flask server with web-service. The web-service hosts restful api.

Method	Endpoint	Usage	Returns
GET	/data/	Get last n sensor data rows. Where n is limit given in script.	List of sensor readouts.
GET	/data/{m}	Get last m sensor data rows. Where m is given parameter. If m>n then service will return n data rows. Where n is limit given in script.	List of sensor readouts.
GET	/last	Get last sensor readout.	Sensor readout.

Sensor readout(JSON):

{"date": "Y-M-D h:m:s.s", "id": id, "temperature": t, "humidity": h}

Example:

{"date": "2015-09-12 11:23:25.126321", "id": 3, "temperature": 20, "humidity": 37}

Request send to / will return index page from template folder.

server.py can be runned separately as a script. If so, it will set up web-service defaultly on host 0.0.0.0 and port 8080.

Usage: server.py [options]

Options:
  -h, --help   show this help message and exit
  --port=PORT  port [default: 8080]
  --host=HOST  host [default: 0.0.0.0]
  -n N         max limit of rows available by /data/ [default: 100]

run_app.py

This script combines run of service.py and record_data.py. The recording class from record_data.py runs as a separate thread.

Usage: you can find options info in server.py and record_data.py or by calling this script with -h options

Options:
  -h, --help   show this help message and exit
  --port=PORT  port [default: 8080]
  --host=HOST  host [default: 0.0.0.0]
  -n N         max limit of rows available by /data/ [default: 100]
  -p           print every record to STDOUT [default: False]
  -t T         time interval in minutes to request readout from sensor
               [default: 15]
  --pin=PIN    data pin connected to sensor [default: 4]
  -s S         number of DHT sensor in use (supported: 11, 22, 2302) [default:
               11]