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Doktorn

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Joined: 09/07/2019
Location: Sweden
Posts: 18

Posted: 02:35pm 02 Nov 2025

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Hi

I have a Json$ file with multiple instances of a label ”SEK_per_kWh”.
On another system I can use print Json$(x$,”SEK_per_kWh[6]”) for
instance nbr 6. I have tried with Print Json$(inp%(),”SEK_per_kWh”)
witch correctly give me the first post but Print Json$(inp%(),”SEK_per_kWh[6]”)
gives nothing.

Can’t get it to work in MM RP2040 V6.00.01.RC6.

My question, how can I parse a Json file with multiple instances of
the same label.

/Lasse

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lizby
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Joined: 17/05/2016
Location: United States
Posts: 3455

Posted: 02:43pm 02 Nov 2025

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Post your entire json string.

PicoMite, Armmite F4, SensorKits, MMBasic Hardware, Games, etc. on fruitoftheshed

Doktorn

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Joined: 09/07/2019
Location: Sweden
Posts: 18

Posted: 02:50pm 02 Nov 2025

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Hi

The file is large, 13620 bytes.

It's this times 96

{"SEK_per_kWh":0.27497,"EUR_per_kWh":0.02498,"EXR":11.007546,"time_start":"2025-11-02T00:00:00+01:00","time_end":"2025-11-02T00:15:00+01:00"}

/Lasse

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Pluto
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Joined: 09/06/2017
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Posts: 394

Posted: 03:43pm 02 Nov 2025

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Hi Lasse,
It seems that we are working with very similar topics! You are parsing swedish and myself finnish electricity prices.

Starting from the long Json$ string (stoted in a longsting buffer) I first search for the first "{" and remove everything up to that point. Then search for the keywords in the Json$. Save data in arrays.
Then again remove the "used" part of the Json$ (LONGSTRING TRIM buff%(),1) and the starting over again.

Here is short part of my code:

WEB open TCP CLIENT url$,80
WEB TCP CLIENT REQUEST Query$,buff%(),15000
WEB close TCP CLIENT
print "TCP time:",timer,"ms"
'a%: position of first "{" in buff%().
print "LLEN(buff%() Part 1:";LLEN(buff%())
a%=LinStr(buff%(),"{")-1: if deb then print "a%=";a%

If a% <> -1 Then
'LongString trim buff%(),a% 'tar bort a% tecken fr?n b?rjan av buff%()
if deb then Print "buff%()=",
if deb then LongString print buff%()

for i=1 to 48

a%=LinStr(buff%(),"{")-1 'find position of first {
LongString trim buff%(),a% 'remove all before {

PriceQuart(i)=CINT(val(Json$(buff%(),"hinta"))*1.255*100)/100 'incl 25.5% VAT
ClockQuart$(i)=right$(Json$(buff%(),"aikaleima_suomi"),5)

a%=a%+1
LongString trim buff%(),1 'remove first char left in buff().(should be "{")

next i

For some unknown reason I was not able to get all 96 datapoints reliably received at once; hence i=1 to 48. (And later a similar sequence for i=49 to 96)

Short dictionary:
hinta: price
aikaleima_suomi: timelabel_finland

My code is based on what others have published on thebackshed. You will probably find better explanations by others in this forum.

Lycka till!

Pluto

Doktorn

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Joined: 09/07/2019
Location: Sweden
Posts: 18

Posted: 08:32pm 02 Nov 2025

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lizby

This is the entire json string.

/Lasse

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Doktorn

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Joined: 09/07/2019
Location: Sweden
Posts: 18

Posted: 09:08pm 02 Nov 2025

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Hi Pluto

Thanks for the tip about parsing my Json$ file. I have used a similar technique when I
decoded XML price documents from the entsoe price database a couple of years ago.
I have an application on an ESP32 with Annex RDS that works well where you can use Json$
in the following way pris$(1)=json$(le$,"SEK_per_kWh[1]”),pris$(2)=json$(le$,"SEK_per_kWh[2]”)
etc. What I was looking for was from the manual's description of the JSON$ parser.

From the manual.
JSON$(a%(), “weather[0].description”) What does the number within [0] mean?

/Lasse

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Pluto
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Joined: 09/06/2017
Location: Finland
Posts: 394

Posted: 08:17am 03 Nov 2025

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Quote JSON$(a%(), “weather[0].description”) What does the number within [0] mean?

The data returned as "weather[0].description" is just a text-string explaining the weather, like "overcast clouds", broken clouds", "heavy snow", "rain" etc.

I have never tried e.g. weather[1].description. I assume that you can have several weather conditions at the same location, e.g. "heavy rain", "strong wind".

Pluto

lizby
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Location: United States
Posts: 3455

Posted: 03:34pm 03 Nov 2025

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I no longer have convenient a webmite with which to test, but from past posts, this is what is typically returned from api.openweathermap.org

Quote {"coord":{"lon":-64.7155,"lat":44.0335},"weather":[{"id":802,"main":"Clouds","description":"scattered clouds","icon":"03d"}],"base":"stations","main":{"temp":278.94,"feels_like":269.44,"temp_min":278.71,"temp_max":279.15,"pressure":1008,"humidity":56},"visibility":10000,"wind":{"speed":10.29,"deg":240,"gust":14.92},"clouds":{"all":46},"dt":1612635812,"sys":{"type":1,"id":549,"country":"CA","sunrise":1612611013,"sunset":1612647345},"timezone":-14400,"id":6057856,"name":"Liverpool","cod":200}

There is no weather[1], only a single instance of the weather values (within "[]"). (But the structure is such that there could be multiple instances.)

The problem that I see with the json string given is that there is no "name" for the multiple "value" instances to be referenced by, and I don't know if there is syntax for which that might work with the MMBasic implementation of json. I made a brief attempt with a picomite and a limited json file using ".[i].SEK_per_kWh"), but got "Error : Dimensions".

I did ask ChatGPT-5 to make a bash script to extract the value. I created a file with just the first 15 values:

Quote [{"SEK_per_kWh":0.27497,"EUR_per_kWh":0.02498,"EXR":11.007546,"time_start":"2025-11-02T00:00:00+01:00","time_end":"2025-11-02T00:15:00+01:00"},
{"SEK_per_kWh":0.22081,"EUR_per_kWh":0.02006,"EXR":11.007546,"time_start":"2025-11-02T00:15:00+01:00","time_end":"2025-11-02T00:30:00+01:00"},
{"SEK_per_kWh":0.23897,"EUR_per_kWh":0.02171,"EXR":11.007546,"time_start":"2025-11-02T00:30:00+01:00","time_end":"2025-11-02T00:45:00+01:00"},
{"SEK_per_kWh":0.21388,"EUR_per_kWh":0.01943,"EXR":11.007546,"time_start":"2025-11-02T00:45:00+01:00","time_end":"2025-11-02T01:00:00+01:00"},
{"SEK_per_kWh":0.2797,"EUR_per_kWh":0.02541,"EXR":11.007546,"time_start":"2025-11-02T01:00:00+01:00","time_end":"2025-11-02T01:15:00+01:00"},
{"SEK_per_kWh":0.25538,"EUR_per_kWh":0.0232,"EXR":11.007546,"time_start":"2025-11-02T01:15:00+01:00","time_end":"2025-11-02T01:30:00+01:00"},
{"SEK_per_kWh":0.22048,"EUR_per_kWh":0.02003,"EXR":11.007546,"time_start":"2025-11-02T01:30:00+01:00","time_end":"2025-11-02T01:45:00+01:00"},
{"SEK_per_kWh":0.20441,"EUR_per_kWh":0.01857,"EXR":11.007546,"time_start":"2025-11-02T01:45:00+01:00","time_end":"2025-11-02T02:00:00+01:00"},
{"SEK_per_kWh":0.23237,"EUR_per_kWh":0.02111,"EXR":11.007546,"time_start":"2025-11-02T02:00:00+01:00","time_end":"2025-11-02T02:15:00+01:00"},
{"SEK_per_kWh":0.24151,"EUR_per_kWh":0.02194,"EXR":11.007546,"time_start":"2025-11-02T02:15:00+01:00","time_end":"2025-11-02T02:30:00+01:00"},
{"SEK_per_kWh":0.24954,"EUR_per_kWh":0.02267,"EXR":11.007546,"time_start":"2025-11-02T02:30:00+01:00","time_end":"2025-11-02T02:45:00+01:00"},
{"SEK_per_kWh":0.23391,"EUR_per_kWh":0.02125,"EXR":11.007546,"time_start":"2025-11-02T02:45:00+01:00","time_end":"2025-11-02T03:00:00+01:00"},
{"SEK_per_kWh":0.30931,"EUR_per_kWh":0.0281,"EXR":11.007546,"time_start":"2025-11-02T03:00:00+01:00","time_end":"2025-11-02T03:15:00+01:00"},
{"SEK_per_kWh":0.31052,"EUR_per_kWh":0.02821,"EXR":11.007546,"time_start":"2025-11-02T03:15:00+01:00","time_end":"2025-11-02T03:30:00+01:00"},
{"SEK_per_kWh":0.30854,"EUR_per_kWh":0.02803,"EXR":11.007546,"time_start":"2025-11-02T03:30:00+01:00","time_end":"2025-11-02T03:45:00+01:00
"}]

Here's the Linux command line, and the results (run on a Seagate Dockstar flashed with openWrt):

Quote cat Sw_kwh.json | jq -r '.[] | .SEK_per_kWh'
0.27497
0.22081
0.23897
0.21388
0.2797
0.25538
0.22048
0.20441
0.23237
0.24151
0.24954
0.23391
0.30931
0.31052
0.30854

In that command the "." in ".[]" implies the entire json string.

I don't know if there is magic which would make a MMBasic json query work with this particular json string.

~
Edited 2025-11-04 01:45 by lizby

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matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 10553

Posted: 03:53pm 03 Nov 2025

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The json listed doesn't conform to the norm. There should be an outer name and then you could access as an array

{
"users": [
{ "name": "Alice", "age": 30 },
{ "name": "Bob", "age": 25 }
]
}

users[1].name

Try appending a name at the beginning and a close bracket at the end as in my example and see if the json$ function then works

Pluto
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Joined: 09/06/2017
Location: Finland
Posts: 394

Posted: 05:02pm 03 Nov 2025

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Lasse,
your data seems to have the same structure as my data so it should be possible to extract your data with the same procedure as I have used. link to earlier post

[{"aikaleima_suomi":"2025-11-03T00:00","aikaleima_utc":"2025-11-02T22:00","hinta":1.544},{"aikaleima_suomi":"2025-11-03T00:15","aikaleima_utc":"2025-11-02T22:15","hinta":1.508},{"aikaleima_suomi":"2025-11-03T00:30","aikaleima_utc":"2025-11-02T22:30","hinta":1.468},{"aikaleima_suomi":"2025-11-03T00:45","aikaleima_utc":"2025-11-02T22:45","hinta":1.448},{"aikaleima_suomi":"2025-11-03T01:00","aikaleima_utc":"2025-11-02T23:00","hinta":1.307},{"aikaleima_suomi":"2025-11-03T01:15","aikaleima_utc":"2025-11-02T23:15","hinta":0.749},......]

(Full day 96 points, but I had to make two TCP requests á 48 points).

Pluto

Doktorn

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Joined: 09/07/2019
Location: Sweden
Posts: 18

Posted: 09:28pm 03 Nov 2025

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Thanks everyone for the tips and suggestions.

matherp, your suggestion about adding group name to Json$ files is correct. Works as expected. But for now I will use my current design which consists of an ESP32-S3 with Annex RDS which retrieves and beautifies the Json$ file. The ESP32 then sends the result serially to the pico. It works great.

Here on a Pico with 7" SSD1963 ( the SSD1963 is not supported in Annex )

/Lasse

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