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"Invalid JSON String" in the Google Visualization API Example

I roughly follow this example . But there must be something stupid ...

Server side Django view code:

data_table = gviz_api.DataTable(description)
data_table.LoadData(data)
json = data_table.ToJSon()
return json

These are the values ​​of the variables copied from the pydev debugger: (Im uses strings for each type of description field for testing purposes only)

Description:

[("sensor","string", "Sensor name"), 
 ("timestamp","string", "Time"),
 ("value","string", "Sensor value")]

Data:

[['testsensor', '2011-05-09 16:06:43.936000', '22.0'],
['testsensor', '2011-05-09 16:56:23.367000', '23.0']]

json (generated google api):

{cols:[{id:'sensor',label:'Sensor name',type:'string'},{id:'timestamp',label:'Time',type:'string'},{id:'value',label:'Sensor value',type:'string'}],rows:[{c:[{v:'testsensor'},{v:'2011-05-09 16:06:43.936000'},{v:'22.0'}]},{c:[{v:'testsensor'},{v:'2011-05-09 16:56:23.367000'},{v:'23.0'}]}]}

Client side javascript code that receives json:

var json_table = new google.visualization.Table(document.getElementById('dataview'));
var json_data = new google.visualization.DataTable(data, 0.6);
json_table.draw(json_data, {showRowNumber: true});

This causes the following error when building the DataTable (second line):

Uncaught Error: Invalid JSON string: {cols:[{id:'sensor',label:'Sensor name',type:'string'},{id:'timestamp',label:'Time',type:'string'},{id:'value',label:'Sensor value',type:'string'}],rows:[{c:[{v:'testsensor'},{v:'2011-05-09 16:06:43.936000'},{v:'22.0'}]},{c:[{v:'testsensor'},{v:'2011-05-09 16:56:23.367000'},{v:'23.0'}]}]}
in default,table.I.js:152

I realized that the whole hint was that the format of the scheme corresponded to the data format, but it seems to be so. It should be something simple.

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4 answers

, , , eval'ing JSON, ?

var json_table = new google.visualization.Table(document.getElementById('dataview'));
var evalledData = eval("("+data+")");
var json_data = new google.visualization.DataTable(evalledData, 0.6);
json_table.draw(json_data, {showRowNumber: true});

, , , ; , .

, , simplejson, json- python , gviz?

+3

, 'unsafe-eval' script Content-Security-Policy.

, Google Google:

<meta
  http-equiv="Content-Security-Policy"
  content="
    default-src 'self';
    script-src 'self' 'unsafe-inline' 'unsafe-eval' maps.googleapis.com www.google.com www.google-analytics.com;
    img-src 'self' csi.gstatic.com www.google-analytics.com maps.gstatic.com maps.googleapis.com;
    style-src 'self' 'unsafe-inline' www.google.com fonts.googleapis.com ajax.googleapis.com;
    font-src 'self' fonts.gstatic.com;
  "
/>
+3

JSON , , JSON RFC 4627:

An object is an unordered collection of zero or more name / value pairs, where name is a string [...] A string begins and ends with quotation marks.

So, JSON should be formatted as follows:

{
    "cols": [
        {
            "id": "sensor",
            "label": "Sensor name",
            "type": "string" 
        },
        {
            "id": "timestamp",
            "label": "Time",
            "type": "string" 
        },
        {
            "id": "value",
            "label": "Sensor value",
            "type": "string" 
        } 
    ],
    "rows": [
        {
            "c": [
                {
                    "v": "testsensor" 
                },
                {
                    "v": "2011-05-09 16: 06: 43.936000" 
                },
                {
                    "v": "22.0" 
                } 
            ] 
        },
        {
            "c": [
                {
                    "v": "testsensor" 
                },
                {
                    "v": "2011-05-09 16: 56: 23.367000" 
                },
                {
                    "v": "23.0" 
                } 
            ] 
        } 
    ]
}
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I had the same problem even if I deprived the option of an empty dictionary (as a result, the error "Invalid JSON string: {}" ...). It turns out the problem is with the script -src CSP described here: https://github.com/keen/keen-js/issues/394

The "solution" is to add unsafe-eval to the CSP.

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