在python中解析json字符串列表

Question

Using an incoming string like list:

[{"FECHA":"2019-01-28 13:15:42","SERIAL":2,"LONGITUD":-4.2958984375,"LATITUD":50.4469470596,"ID":1,"VALOR":193,"JOURNEYID":1},
{"FECHA":"2019-01-28 13:15:44","SERIAL":3,"LONGITUD":-4.2958984375,"LATITUD":40.4469470596,"ID":1,"VALOR":34,"JOURNEYID":1},
{"FECHA":"2019-01-28 13:15:46","SERIAL":6,"LONGITUD":-3.2958984375,"LATITUD":50.4469470596,"ID":1,"VALOR":14,"JOURNEYID":1},<..>]

With a lenght N and each element with the following format:

{"FECHA":"2019-01-28 13:15:42","SERIAL":2,"LONGITUD":-4.2958984375,"LATITUD":50.4469470596,"ID":1,"VALOR":193,"JOURNEYID":1}

What I want?

Iterate the list and process each JSON elem individually

first output: {"FECHA":"2019-01-28 13:15:42","SERIAL":2,"LONGITUD":-4.2958984375,"LATITUD":50.4469470596,"ID":1,"VALOR":193,"JOURNEYID":1}

second output: {"FECHA":"2019-01-28 13:15:44","SERIAL":3,"LONGITUD":-4.2958984375,"LATITUD":40.4469470596,"ID":1,"VALOR":34,"JOURNEYID":1}

<...>

How could I split to take each JSON element?

---

What I have tried:

Option 1:

def ParseIncomingDataAzure(message):
    print ("incoming data: {}".format(message))
    x = ast.literal_eval(message)
    for frame in x:
        print("x: {}".format(frame))

Output:

x: {'LATITUD': 50.4469470596, 'FECHA': '2019-01-28 13:15:42', 'JOURNEYID': 1, 'VALOR': 193, 'SERIAL': 2, 'ID': 1, 'LONGITUD': -4.2958984375}
x: {'LATITUD': 40.4469470596, 'FECHA': '2019-01-28 13:15:44', 'JOURNEYID': 1, 'VALOR': 34, 'SERIAL': 3, 'ID': 1, 'LONGITUD': -4.2958984375}
x: {'LATITUD': 50.4469470596, 'FECHA': '2019-01-28 13:15:46', 'JOURNEYID': 1, 'VALOR': 14, 'SERIAL': 6, 'ID': 1, 'LONGITUD': -3.2958984375}

---

Option 2:

def ParseIncomingDataAzure(message):
    messages = message.split(",")
    for frame in messages:
        print("x: {}".format(frame))

Output:

x: [{"FECHA":"2019-01-28 13:15:42"
x: "SERIAL":2
x: "LONGITUD":-4.2958984375
x: "LATITUD":50.4469470596
x: "ID":1
x: "VALOR":193
x: "JOURNEYID":1}
x: {"FECHA":"2019-01-28 13:15:44"
x: "SERIAL":3
x: "LONGITUD":-4.2958984375
x: "LATITUD":40.4469470596
x: "ID":1
x: "VALOR":34
x: "JOURNEYID":1}
x: {"FECHA":"2019-01-28 13:15:46"
x: "SERIAL":6
x: "LONGITUD":-3.2958984375
x: "LATITUD":50.4469470596
x: "ID":1
x: "VALOR":14
x: "JOURNEYID":1}]

---

Option 3:

Simple for to iterate over the list

def ParseIncomingDataAzure(message):
    for frame in message:
         print("x: {}".format(frame))

Output:

x: [
x: {
x: "
x: F
x: E
x: C
x: H
x: A
<....>

---

Possible solution:

def ParseIncomingDataAzure(message):
    print ("incoming data: {}".format(message))
    x = ast.literal_eval(message)
    for frame in x:
        print("x: {}".format(json.dumps(frame)))

Is this the correct way?

Answer 1

Consider using the json package for this:

In [2]: import json                                                                                                                                                                                                                                                                       
In [3]: s = '{"FECHA":"2019-01-28 13:15:42","SERIAL":2,"LONGITUD":-4.2958984375,"LATITUD":50.4469470596,"ID":1,"VALOR":193,"JOURNEYID":1}'                                                                                                                                                
In [4]: json.loads(s)                                                                                                                                                                                                                                                                     
Out[4]: 
{'FECHA': '2019-01-28 13:15:42',
 'SERIAL': 2,
 'LONGITUD': -4.2958984375,
 'LATITUD': 50.4469470596,
 'ID': 1,
 'VALOR': 193,
 'JOURNEYID': 1}

Answer 2

This both functions solved my use case:

def ParseIncomingDataAzure(message):
    print ("incoming data: {}".format(message))
    x = ast.literal_eval(message)
    for frame in x:
        print("x: {}".format(json.dumps(frame)))
        <...>

The inconvenient of the following function is that you will need to know the position where the "," is separating each element of the incoming list, so for real data where the number of fields of the json could be different in each element of the list you can not use:

def ParseIncomingDataAzure(message):
    n = 7
    frames = message.split(",")
    while frames:
        y= ','.join(frames[:n])
        frames = frames[7:]
        print (y)