Help with json conversion

I have to admit, up front, I'm a complete Python novice, almost no experience, old-school programmer. Maybe someone can push this old man in the right direction.

I have a script, as follows:

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import requests
import datetime
import json
url = 'http://10.0.1.96/index.php/pages/main/gaugeValues/2162'
indigo.server.log("Test Script Executed")
reply = requests.get(url, timeout=1.0)
indigo.server.log(reply.content)

result = json.loads(reply.text)
for item in result[0]:
   indigo.server.log(item)

Output to the log is:
Script Test Script Executed
Script [{"chanId":"","maxWatt":10161.8,"currWatt":1690,"minWatt":24,"unit":"W","netWatts":0,"tmpWatt":0}]
Script netWatts
Script chanId
Script currWatt
Script tmpWatt
Script maxWatt
Script unit
Script minWatt

What I want is the value of the item, not the item description, i.e. What is the value following "currWatt"? Probably real easy but I don't know how to do it.

Thank you.

"for item in someDict" returns the keys of the dict, not the values. Try:

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import requests
import datetime
import json
url = 'http://10.0.1.96/index.php/pages/main/gaugeValues/2162'
indigo.server.log("Test Script Executed")
reply = requests.get(url, timeout=1.0)
indigo.server.log(reply.content)

result = json.loads(reply.text)
for key, value in result[0].iteritems():
   indigo.server.log("{} -> {}".format(key, value))


or

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result = json.loads(reply.text)
for key in result[0]:
   indigo.server.log("{} -> {}".format(key, result[0][key]))


Thank you so much!

First option didn't display values but the second option works perfectly.

This code works and display, in the log, the key and the value:

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result = json.loads(reply.text)
for key in result[0]:
   indigo.server.log("{} -> {}".format(key, result[0][key]))

How do I assign a value of a specific key to an Indigo variable?

As I said in my post, a complete novice, long-time programmer, no python experience (or any other modern language) so these variable constructs completely overwhelm me. However, given an example, I can make things work.

And THANK YOU, in advance.

Here's the indigo method you need to call. First argument is the name or (preferred) the ID of the Indigo variable. Second argument is the value to set it to, which is pulled from the result dict.

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        indigo.variable.updateValue("currWatt", result[0]["currWatt"])


There's some really good on-line Python classes out there. Less than 10 hours will get you a good start.

[jay (support)]

Can you post the actual JSON returned by the requests.get() call? I suspect that's going to shed some light on the confusion...

Can you post the actual JSON returned by the requests.get() call? I suspect that's going to shed some light on the confusion...

It was buried in the original post:

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 [{"chanId":"","maxWatt":10161.8,"currWatt":1690,"minWatt":24,"unit":"W","netWatts":0,"tmpWatt":0}]


Hi lvrouter,

well, this may be a bit off, but have you seen DaveL's GhostXML Plugin?
It does JSON very well.
Cheers
Wilhelm

When I do this:

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indigo.variable.updateValue("PowerString", reply.text)


It correctly sets the variable to the text returned by the server query (the json string)
Which is;

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[{"chanId":"","maxWatt":10222.3,"currWatt":2756,"minWatt":24,"unit":"W","netWatts":0,"tmpWatt":0}]


When I do this:

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indigo.variable.updateValue("PowerString", result[0]["currWatt"])


I get this error message:

Script Error embedded script: Python argument types in VariableCmds.updateValue(VariableCmds, str, int) did not match C++ signature:
updateValue(_VariableCmds {lvalue}, boost::python::api::object elem, CCString value)
Script Error Exception Traceback (most recent call shown last):

embedded script, line 17, at top level
ArgumentError: Python argument types in VariableCmds.updateValue(VariableCmds, str, int)did not match C++ signature:
updateValue(_VariableCmds {lvalue}, boost::python::api::object elem, CCString value)

Changing the reference to the Python Variable Id as follows:

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indigo.variable.updateValue(indigo.variables[424021792], result[0]['currWatt'])


Generates the exact same error message.

I have used GhostXML on older versions and when I set this up it doesn't return any values or error. It shows as "updated'. No error, just no values and I can't setup a virtual device as a result.

Well, I made progress. Variable type mismatch, this works:

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indigo.variable.updateValue("PowerString", str(result[0]["currWatt"]))


My bad, I always forget that Indigo variables have to be strings. But then, I don't use them much.

[jay (support)]

It was buried in the original post:

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 [{"chanId":"","maxWatt":10161.8,"currWatt":1690,"minWatt":24,"unit":"W","netWatts":0,"tmpWatt":0}]


Oh, right, I should have seen that.

Note - you really should use variable IDs (or instances) rather than names in all method calls that take an Indigo object (variable, device, etc) since names can change but IDs can't. So:

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indigo.variable.updateValue(424021792, str(result[0]['currWatt']))

is the recommended approach.

I think a brief explanation of the JSON is appropriate. Here it is formatted so it's a little more readable:

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[
  {
    "chanId": "",
    "currWatt": 1690,
    "maxWatt": 10161.8,
    "minWatt": 24,
    "netWatts": 0,
    "tmpWatt": 0,
    "unit": "W"
  }
]


The brackets ([]) are an indication of a list. In this case, there is only one element, which is a dictionary. The dictionary is bounded by braces ({}). Each entry in the dictionary has a key (i.e. "currWatt") followed by a colon followed by the value (i.e. 1690).

So, you can say the "currWatt" value of the first dictionary in the list. Once you convert the JSON into native Python objects:

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import json
result = json.loads(reply.text)
# result is a list
# In your example, it has only 1 object, which is a dictionary
first_dict = result[0]
# first_dict has 7 entries, one being "currWatt"
curr_watt_value = first_dict["currWatt"]
# curr_watt_value is a number - you can tell by looking at the JSON where the value 1690 isn't enclosed in quotes,
# or in Python, use the type() function
print(type(curr_watt_value))