Creating a nested JSON request with Python - python

A user needs to pass a json object as a part of the request. It would look something like this:
{"token" :"ayaljltja",
"addresses": [
{'name':'Home','address':'20 Main Street',
'city':'new-york'},
{'name':'work', 'address':'x Street', 'city':'ohio'}
]}
I have two problems right now. First, I can't figure out how to test this code by recreating the nested POST. I can successfully POST a dict but posting the list of addresses within the JSON object is messing me up.
Simply using cURL, how might I do this? How might I do it with urrlib2?
My second issue is then deserializing the JSON POST object on the server side. I guess I just need to see a successful POST to determine the input (and then deserialize it with the json module).
Any tips?

First make sure your JSON is valid. Paste it into the JSONLint web page.
Currently your JSON has two issues:
there is no comma between "token" :"ayaljltja" and "addresses": [...]
a single quote is not a valid way of delimiting a JSON string, replace them all with double quotes.

With command line curl, save your JSON to a file, say data.json. Then try: curl -X POST -d #data.json http://your.service.url
It's also possible to enter the JSON directly to the -d parameter but (as it sounds like you know already) you have to get your quoting and escaping exactly correct.

Related

Python Dictionary JSON Key, Val Extraction

I'm having a hard time understanding what is going on with this walmart API and I can't seem to iterate through key, values like I wish. I get different errors depending on the way I attack the problem.
import requests
import json
import urllib
response=requests.get("https://grocery.walmart.com/v0.1/api/stores/4104/departments/1256653758154/aisles/1256653758260/products?count=60&start=0")
info = json.loads(response.text)
print(info)
I'm not sure if I'm playing with a dictionary or a JSON object.
I'm thrown off because the API itself has no quotes over key/val.
When I do a json.loads it comes in but only comes in with single quotes.
I've tried going at it with for-loops but can only traverse the top layer and nothing else. My overall goal is to retrieve the info from the API link, turn it into JSON and be able to grab which ever key/val I need from it.
I'm not sure if I'm playing with a dictionary or a JSON object.
Python has no concept of a "JSON Object". It's a dictionary.
I'm thrown off because the API itself has no quotes over key/val.
Yes it does
{"aisleName":"Organic Dairy, Eggs & Meat","productCount":17,"products":[{"data":
When I do a json.loads it comes in but only comes in with single quotes
Because it's a Python dictionary, and the repr() of dict uses single quotes.
Try print(info['aisleName']) for example

Sending json data through curl/urllib2 to Pyramid application does not give a proper request.POST

I'm currently testing out creating a RESTful json API, and in the process I've been testing out posting data via curl primarily to see if I can login through a request. I can't figure out what to do even if I hack it to work, but that's a separate question.
I'm sending the following POST request to my app:
curl -X POST http://localhost:6543/users/signin -d '{"username":"a#a.com","password":"password"}'
And when I see what data is in my request, the output is extremely strange:
ipdb> self.request.POST
MultiDict([('{"username":"a#a.com","password":"password"}', '******')])
ipdb> self.request.POST.keys()
['{"username":"a#a.com","password":"password"}']
ipdb> self.request.POST.values()
[u'']
So, it comes out to be a MultiDict with my json object as a string key, and a blank string as its value?! That doesn't seem right.
Removing the single quotes in my json declaration gives the following:
ipdb> self.request.POST
MultiDict([('username:a#a.com', u'')])
Does anyone have any idea why my data may not be being posted correctly?
Update:
To be clear, the header I'm using is in fact application/x-www-form-urlencoded.
ipdb> self.request.headers['CONTENT-TYPE']
'application/x-www-form-urlencoded'
What I DID find is that for some reason using the requests library works when I do the following:
In [49]: s.post('http://localhost:6543/users/signin', data=[('username', 'a#a.com'), ('password', 'password')], headers={'content-type': 'application/x-www-form-urlencoded'})
Out[49]: <Response [200]>
The fact that it doesn't work with curl as expected is still troubling though.
I'm not sure which content type you are attempting to upload - application/json or application/x-www-form-urlencoded. request.POST only works with the latter option, and request.json_body is used to parse data from a json request body.
To be clear, application/x-www-form-urlencoded is the format used when your web browser submits a form. It's a key/value format looking like a=b&c=d&e=f. From there you can expect request.POST to contain a dictionary with the keys a, c, and e.

Push a raw value to Firebase via REST API

I am trying to use the requests library in Python to push data (a raw value) to a firebase location.
Say, I have urladd (the url of the location with authentication token). At the location, I want to push a string, say International. Based on the answer here, I tried
data = {'.value': 'International'}
p = requests.post(urladd, data = sjson.dumps(data))
I get <Response [400]>. p.text gives me:
u'{\n "error" : "Invalid data; couldn\'t parse JSON object, array, or value. Perhaps you\'re using invalid characters in your key names."\n}\n'
It appears that they key .value is invalid. But that is what the answer linked above suggests. Any idea why this may not be working, or how I can do this through Python? There are no problems with connection or authentication because the following works. However, that pushes an object instead of a raw value.
data = {'name': 'International'}
p = requests.post(urladd, data = sjson.dumps(data))
Thanks for your help.
The answer you've linked is a special case for when you want to assign a priority to a value. In general, '.value' is an invalid name and will throw an error.
If you want to write just "International", you should write the stringified-JSON version of that data. I don't have a python example in front of me, but the curl command would be:
curl -X POST -d "\"International\"" https://...
Andrew's answer above works. In case someone else wants to know how to do this using the requests library in Python, I thought this would be helpful.
import simplejson as sjson
data = sjson.dumps("International")
p = requests.post(urladd, data = data)
For some reason I had thought that the data had to be in a dictionary format before it is converted to stringified JSON version. That is not the case, and a simple string can be used as an input to sjson.dumps().

extract json data from post body request with python

Is there a way to easily extract the json data portion in the body of a POST request?
For example, if someone posts to www.example.com/post with the body of the form with json data, my GAE server will receive the request by calling:
jsonstr = self.request.body
However, when I look at the jsonstr, I get something like :
str: \r\n----------------------------8cf1c255b3bd7f2\r\nContent-Disposition: form-data;
name="Actigraphy"\r\n Content-Type: application/octet-
stream\r\n\r\n{"Data":"AfgCIwHGAkAB4wFYAZkBKgHwAebQBaAD.....
I just want to be able to call a function to extract the json part of the body which starts at the {"Data":...... section.
Is there an easy function I can call to do this?
there is a misunderstanding, the string you show us is not json data, it looks like a POST body. You have to parse the body with something like cgi.parse_multipart.
Then you could parse json like answered by aschmid00. But instead of the body, you parse only the data.
Here you can find a working code that shows how to use cgi.FieldStorage for parsing the POST body.
This Question is also answered here..
It depends on how it was encoded on the browser side before submitting, but normally you would get the POST data like this:
jsonstr = self.request.POST["Data"]
If that's not working you might want to give us some info on how "Data" was encoded into the POST data on the client side.
you can try:
import json
values = 'random stuff .... \r\n {"data":{"values":[1,2,3]}} more rnandom things'
json_value = json.loads(values[values.index('{'):values.rindex('}') + 1])
print json_value['data'] # {u'values': [1, 2, 3]}
print json_value['data']['values'] # [1, 2, 3]
but this is dangerous and takes a fair amount of assumptions, Im not sure which framework you are using, bottle, flask, theres many, please use the appropriate call to POST
to retrieve the values, based on the framework, if indeed you are using one.
I think you mean to do this self.request.get("Data") If you are using the GAE by itself.
https://developers.google.com/appengine/docs/python/tools/webapp/requestclass#Request_get
https://developers.google.com/appengine/docs/python/tools/webapp/requestclass#Request_get_all

Python grabbing JSON from POST method

I have an Android appthat originally posted some strings in json format to a python cgi script, which all worked fine. The problem is when the json object contains lists, then python (Using simplejson) when it gets them is still treating them as a big string
Here is a text dump of the json once it reaches python before I parse it:
{"Prob1":"[1, 2, 3]","Name":"aaa","action":1,"Prob2":"[20, 20, 20]","Tasks":"[1 task, 2 task, 3 task]","Description":""}
if we look at the "Tasks" key, the list after is clearly a single string with the elements all treated as one string (i.e. no quotes around each element). it's the same for prob1 and prob2. action, Name etc are all fine. I'm not sure if this is what python is expecting but I'm guessing not?
Just in case the android data was to blame i added quotes around each element of the arraylist like this:
Tasks.add('"'+row.get(1).toString()+'"'); instead of Tasks.add(row.get(1).toString());
On the webserver it's now received as
{"Prob1":"[1, 2, 3]","Name":"aaa","action":1,"Prob2":"[20, 20, 20]","Tasks":"[\"1 task\", \"2 task\", \"3 task\"]","Description":""}
but i still get the same problem; when i iterate through "Tasks" in a loop it's looping through each individual character as if the whole thing were a string :/
Since I don't know what the json structure should look like before it gets to Python I'm wondering whether it's a probem with the Android sending the data or my python interpreting it.. though from the looks of that script I've been guessing it's been the sending.
In the Android App I'm sending one big JSONObject containing "Tasks" and the associated arraylist as one of the key value pairs... is this correct? or should JSONArray be involved anywhere?
Thanks for any help everyone, I'm new to the whole JSON thing as well as to Android/Java (And only really a novice at Python too..). I can post additional code if anyone needs it, I just didn't want to lengthen the post too much
EDIT:
when I add
json_data=json_data.replace(r'"[','[')
json_data=json_data.replace(r']"',']')
json_data=json_data.replace(r'\"','"')
to the python it WORKS!!!! but that strikes me as a bit nasty and just papering over a crack..
Tasks is just a big string. To be a valid list, it would have to be ["1 task", "2 task", "3 task"]
Same goes for Prob1 and Prob2. To be a valid list, the brackets should not be enclosed in quotes.

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