在Raspberry Pi Weather Station的JavaScript中读取（从保管箱）.txt文件的问题

Question

How exactly would I go by reading .txt files in JavaScript from a dropbox file? I recently got a weather sensor for my raspberry pi, and I want to save the current weather data every hour to a .txt file in dropbox (code seen below). However, I am a bit stuck on linking the data from a dropbox file to my web page so I can chart graphs of weather patterns.

I have tried using the Dropbox API but to no avail.

Below is my code in Python:

# Weather Station App by Rob

# Will get current temperatures every minute, then will write data to a seperate file, which will then be added to dropbox.

from time import *
from random import randint

def writeTemperature():
    output = open("output.txt", "w")

    # Instead of using a variable, get the temperature from the Raspberry Pi.
    # Fahrenheight or Celcius
    temperature = randint(1, 32)

    listOfTemperatures.append(temperature)

    averageTotal = 0

    for temp in listOfTemperatures:
        averageTotal = averageTotal + temp

    average = averageTotal / len(listOfTemperatures)

    output.write(("Temperature: " + str(temperature)) + '\n')
    output.write("Average: " + str(average)) 
    output.write(listOfTemperatures)

    print "Added!"

    output.close()

listOfTemperatures = []
average = 0    

while True:
    writeTemperature()
    sleep(1)

The function saves the weather data to a file. (Ignore the temperature variable and the sleep function, was just debugging)

The output.txt file will look like:

Temperature: 22
Average: 12

After this, my only trouble is linking it to JavaScript. Just confused on this part. Pointers in the right direction would be well appreciated.

Thank you.

Answer 1

linking the data from a dropbox file to my web page

As far as i know you cannot simply load a local file into your browser javascript. What you can do is setup a simple webserver like pythons SimpleHTTPServer or a simple nodejs server with express.js . Then deliver your html, js and define a route for loading your text file via an ajax for instance.

Express.js example:

var express = require('express')
var app = express()

app.get('/', function (req, res) {
  res.sendFile('index.html')
})

app.use(express.static('public')) // now you can load any file from your public folder (e.g. public/weather_data.txt)

app.listen(3000, function () {
  console.log('Example app listening on port 3000!')
})

In your browsers javascript you can then do (using jquery):

$.ajax({
  url: "./public/weather_data.txt",
  async: false,
  success: function (data){
    // Do whatever you want with the data
    document.getElementById('myElement').innerHTML = data
  }
})

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