Python parsing json issue - python

I'm having troubles parsing a complicated json. That is it:
{
"response": {
"players": [
{
"bar": "76561198034360615",
"foo": "49329432943232423"
}
]
}
}
My code:
url = urllib.urlopen("foobar").read()
js = json.load(url)
data = js['response']
print data['players']
The problem is that this would print the dict. What I want is to reach the key's values, like foo and bar. What I tried so far is doing data['players']['foo'] and it gives me an error that list indices should be integers, I tried of course, it didn't work. So my question is how do I reach these values? Thanks in advance.

data['response']['players'] is an array (as defined by the brackets ([, ]), so you need to access items using a specific index (0 in this case):
data['players'][0]['foo']
Or iterate over all players:
for player in data['response']['players']:
print player['foo']

The problem is that players is a list of items ([ ] in json). So you need to select the first and only item in this case using [0].
print data['players'][0]['foo']
But, keep in mind that you may have more than one player, in which case you either need to specify the player, or loop through the players using a for loop
for player in data['players']:
print player['foo']

Related

How to change the value of a JSON list?

I know for fact that this question has been asked before. I looked at the following posts:
Python replace values in unknown structure JSON file
How to find and replace a part of a value in json file
https://pretagteam.com/question/how-to-replace-a-value-in-json-file-using-python
How to find and replace a part of a value in json file (Somehow this is what I am looking for but it does not fit my problem with the links being different and stored all under "latest")
and much more contributions, however I am still stuck.
I have a simple JSON structure like this:
{
"guild1": {
"latest": [
"link1",
"link2"
],
"channel": channel_here
},
"guild2": {
"latest": [
"link"
],
"channel": channel_here
}
}
I found a way to iterate over the entries and print the list in which the condition is found, for example:
# searching for link 1
["link1", "link2", "link3"] # here link 1 for example is found in one of the list entries
["link5"] -> This for example does not match what I am looking for, I can ignore this
If found, I simply want to replace it (just link1) with another before defined value. I tried to iterate over the keys of the found list but was not able to .replace it or something else. The key which matches my search criteria is printed out, but I can't do anything else with it. Is it even possible to change the entry in a list that easy?
Mostly I also got the following error which I also looked up but did not get any did not get any wiser:
TypeError: string indices must be integers
Here is how I search for the list end the "entries":
if defined_link in data[searchloop]['latest']: # data is my JSON file, searchloop the for-loop
for key in data[searchloop]['latest']: # Get all the matching keys
if key == defined_link: # Get the key I am looking for
Maybe someone else can help me here!
This code would change one value in a list (here 'link1') to another:
L = ["link1", "link2", "link3"]
L[L.index('link1')] = 'someOtherValue'
After this you would see that L changed to ["someOtherValue", "link2", "link3"]
You first find at which index is 'link1', let's say you get back 3. So, you know you have to change the value of L[3]. Now it's simple. Do L[3] = 'someOtherValue'.
Iterate over each guild in the json structure.
Iterate over each link in that guild's "latest" list.
If the link matches, assign that list item to something else.
for guild in jsonstructure:
for i in range(len(jsonstructure[guild]['latest'])):
if jsonstructure[guild]['latest'][i] == 'something':
jsonstructure[guild]['latest'][i] = 'new thing'
I think you should try
list.append(i)
It will work I faced same problem
For example:
string = "Hello World!"
list = []
for i in string:
list.append(string[i])
print(list)

Accessing Nested JSON [AWS Metadata] with Python

I'm using Lambda to run through my AWS account, returning a list of all instances. I need to be able to print out all of the 'VolumeId' values, but I can't work out how to access them as they are nested. I am able to print out the first VolumeId for each instance, however, some of the instances have several volumes, and some only have one. I think I know why I get these results, but I can't work out what to do to get all of them back.
Here's a snippet of what the JSON for one instance looks like:
{
'Groups':[],
'Instances':[
{
'AmiLaunchIndex':0,
'ImageId':'ami-0',
'InstanceId':'i-0123',
'InstanceType':'big',
'KeyName':'nonprod',
'LaunchTime':'date',
'Monitoring':{
'State':'disabled'
},
'Placement':{
'AvailabilityZone':'world',
'GroupName':'',
'Tenancy':'default'
},
'PrivateDnsName':'secret',
'PrivateIpAddress':'1.2.3.4',
'ProductCodes':[
],
'PublicDnsName':'',
'State':{
'Code':80,
'Name':'stopped'
},
'StateTransitionReason':'User initiated',
'SubnetId':'subnet-1',
'VpcId':'vpc-1',
'Architecture':'yes',
'BlockDeviceMappings':[
{
'DeviceName':'/sda',
'Ebs':{
'AttachTime':'date',
'DeleteOnTermination':True,
'Status':'attached',
'VolumeId':'vol-1'
}
},
{
'DeviceName':'/sdb',
'Ebs':{
'AttachTime':'date'),
'DeleteOnTermination':False,
'Status':'attached',
'VolumeId':'vol-2'
}
}
],
This is what I'm doing to get the first VolumeId:
ec2client = boto3.client('ec2')
ec2 = ec2client.describe_instances()
for reservation in ec2["Reservations"]:
for instance in reservation["Instances"]:
instanceid = instance["InstanceId"]
volumes = instance["BlockDeviceMappings"][0]["Ebs"]["VolumeId"]
print("The associated volume IDs for this instance are: ",(volumes))
I think the reason that I'm getting just the first ID is because I'm referencing the first element within "BlockDeviceMappings", but I can't work out how to get the other ones. If I try it without specifying the [0], I get the list indices must be integers or slices, not str error. I tried to use a dictionary instead of a list too, but felt like I was barking up the wrong tree with that one. Any suggestions/help would be appreciated!
One possible answer, not particularly pythonic
...
id_list = []
volumes_data = instance["BlockDeviceMappings"]
for element in volumes_data:
id_list.append(element["Ebs"]["VolumeId"])
Or else use json.loads and then iterate though json using .get syntax like the final answer in this

Reference all indexes in list and check for existence of value in python

I'm trying to create if block in my python3 script that checks if a value exists within a list I pull from JSON. The JSON data is below:
[
{
"id": 59616405645,
"name": "Foo"
},
{
"id": 990164054345,
"name": "FindMe"
},
{
"id": 2009167874,
"name": "Bar"
}
]
I'm trying to determine whether or not the value of Bar exists within the list. To do so I'm doing the following which directly references the index:
if "FindMe" in m_orgs[1].values():
print("Yo it's here")
else:
print("Yo it's not here.")
But the JSON data I'm pulling will always have different results and we will never know the index numbers, so direct reference will not work. How do I reference all indexes in a list at once?
You can't reference all indexes at once, but you can loop through them, and stop as soon as you find the first existence. Something like:
found = any("findMe" in item.values() for item in m_orgs)
This line will stop the execution when it finds the first True value. So worst case, it will look through every position and not find anything.
You can use any() like this:
if any(d['name'] == 'Foo' for d in json):
do this
You can first translate the original json data to set of data, and then simply check through set operations,
name_set = {org['name'] for org in m_orgs}
print 'FindMe' in name_set

TypeError : Trouble accessing JSON metadata with Python

So I'm trying to access the following JSON data with python and when i give the statement :
print school['students']
The underlying data gets printed but what I really want to be able to do is print the 'id' value.
{ 'students':[
{
'termone':{
'english':'fifty',
'science':'hundred'
},
'id':'RA1081310005'
}
]
}
So when I do the following I get an error :
print school ['students']['id']
TypeError: list indices must be integers, not str
Can anyone suggest how i can access the ID & where I'm going wrong!
school['students'] is a list. You are trying to access the first element of that list and id key belongs to that element. Instead, try this:
school['students'][0]['id']
Out: 'RA1081310005'
The problem here is that in your list, 'id' is not a part of a dictionary, it is part of a list. To fix this, change your dictionary to the following:
school = {'students':{
'termone': {
"english": "fifty:,
"science": "hundred
},
"id":"RA1081310005"
}
}
Basically, you have a list, and there is no reason to have it, so I removed it.

How do I use a for loop when reading from a dictionary that might contain a list of dicts, but might not?

I apologize in advance that the title is so confusing. It makes a lot more sense in code, so here goes:
I am parsing data from a REST API that returns JSON, and I have a bit of an issue with this particular structure:
{ 'Order' : [
{ 'orderID': '1',
'OrderLines': {
'OrderLine': [
{ 'lineID':'00001', 'quantity':'1', 'cost':'10', 'description':'foo' },
{ 'lineID':'00002', 'quantity':'2', 'cost':'23.42', 'description':'bar' }
]}
}
{ 'orderID': '2',
'OrderLines': {
'OrderLine':
{ 'lineID':'00003', 'quantity':'6', 'cost':'12.99', 'description':'lonely' }
}
}
]}
If you'll notice, the second order only has one OrderLine, so instead of returning a list containing dictionaries, it returns the dictionary. Here is what I am trying to do:
orders_json = json.loads(from_server)
for order in orders_json['Order']:
print 'Order ID: {}'.format(order['orderID'])
for line in order['OrderLines']['OrderLine']:
print '-> Line ID: {}, Quantity: {}'.format(line['lineID'], line['quantity'])
It works just fine for the first order, but the second order throws TypeError: string indices must be integers since line is now a string containing the dictionary, instead of a dictionary from the list. I've been banging my head against this for hours now, and I feel like I am missing something obvious.
Here are some of the things I have tried:
Using len(line) to see if it gave me something unique for the one line orders. It does not. It returns the number of key:value pairs in the dictionary, which in my real program is 10, which an order containing 10 lines would also return.
Using a try/except. Well, that stops the TypeError from halting the whole thing, but I can't figure out how to address the dictionary once I've done that. Line is a string for single line orders instead of a dictionary.
Whoever designed that API did not do a terribly good job. Anyway, you could check whether OrderLine is a list and, if it's not, wrap it in a one-element list before doing any processing:
if not isinstance(order_line, list):
order_line = [order_line]
That would work, my personal preference would be to get the API fixed.
I'd check if the type is correct and then convert it to a list if necessary to have a uniform access:
lines = order['OrderLines']['OrderLine']
lines = [lines] if not isinstance(lines, list) else lines
for line in lines:
...
You can check the type of the object you try to access:
# ...
print 'Order ID: {0}'.format(order['orderID'])
lines = order['OrderLines']['OrderLine']
if isinstance(lines, list):
for line in lines:
print line['lineID']
elif isinstance(lines, dict):
print lines['lineID']
else:
raise ValueError('Illegal JSON object')
Edit: Wrapping the dict in a list as proposed by #NPE is the nicer and smarter solution.

Categories