I am trying to create API for my Flask project. I have data stored in mongoDB and for building API I am using flask_restful. The problem is that in JSON are added escaped quotes and I cannot figure why and I rather have my JSON without them.
This is how my get function looks like:
from flask_restful import Resource
import json
from bson import json_util
class Harvests(Resource):
def get(self):
json_docs = []
for doc in db.collection.find():
json_doc = json.dumps(doc, default=json_util.default)
json_docs.append(json_doc)
return json_docs
In app.py it is just like that
api = Api(app)
api.add_resource(Harvests, '/api/harvests')
And I get JSON with escaped quotes (in browser or with curl)
[
"{\"_id\": {\"$oid\": \"5c05429cc4247917d66163a7\"},...
]
If I try this outside Flask (print JSON from mongo) and it works just fine. I tried use .replace(), but I think is not most elegant solution, but it did not work anyway. Any idea how I should get rid off these backslashes?
What you see is absolutely what you should expect to see according to your code, so I think there is a misunderstanding at some point. Let me explain what you are doing.
You convert each doc (a data structure) into a jsonified version (a string) of this data. Then you gather these strings in a list. Later you see this list, and of course you see a list of strings. Each of these strings contains a jsonified version of a data structure (a dictionary with opening braces, keys and values inside, and each key is a string itself with quotes, so these quotes are escaped within the jsonified string).
I recommend to collect your documents into a list and then convert that list to json instead:
def get(self):
docs = []
for doc in db.collection.find():
docs.append(doc)
return json.dumps(docs, default=json_util.default)
This way you get one json string representing the list of docs.
Maybe your framework is already applying a jsonifying automatically, in this case just don't do this step yourself:
return docs
Just use this instead.
Related
I'm using an API that is giving me and output formatted as
['{"quote":{"symbol":"AAPL"', '"companyName":"Apple Inc."', '"primaryExchange":"Nasdaq Global Select"', '"sector":"Technology"', '"calculationPrice":"close"', '"open":367.88', '"openTime":1593696600532', '"close":364.11', '"closeTime":1593720000277', '"high":370.47', '"low":363.64', '"latestPrice":364.11'}]
...(it keeps going like this with many more categories.)
I am attempting to pull out only the latest price. What would be the best way to do that?
This is what I have but I get a bunch of errors.
string = (data.decode("utf-8"))
data_v = string.split(',')
for word in data_v[latestPrice]:
if word == ["latestPrice"]:
print(word)
print(data_v)
Judging by the output this is JSON. To parse this easily use the JSON module (see https://docs.python.org/3/library/json.html ).
If I'm correct you got this output from Yahoo Finance, if this indeed the case don't fetch and parse it manually but use the yfinance module (see https://pypi.org/project/yfinance/ )
You will have to use JSON module to parse this JSON string. You can convert it into dictionary then. I have indented the JSON code for ease of understanding. You can use the following approach,
import json
text_to_parse = """
{"quote":
{
"symbol":"AAPL",
"companyName":"Apple Inc.",
"primaryExchange":"Nasdaq Global Select",
"sector":"Technology",
"calculationPrice":"close",
"open":367.88,
"openTime":1593696600532,
"close":364.11,
"closeTime":1593720000277,
"high":370.47,
"low":363.64,
"latestPrice":364.11
}
}
"""
parsed_dict = json.loads(text_to_parse)
print(parsed_dict["quote"]["latestPrice"])
When the program is run, it outputs 364.11
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
I see Flask provides a few parsed fields in Request, however the url is after removing escapes. Any way to access the url prior to un-escaping done by Flask?
For example when a rest client makes request for "http://www.example.com/my_url%20is%20here?arg1=2&?arg2=3", Flask provides me with the request.base_url of "http://www.example.com/my_url is here" where %20 is replaced with spaces. I can quote this myself to get the original URL as someone responded, but preferably I would like to access the original URL as it was sent by the client rather than deriving it.
The fields are not URLs, or even URIs, they are IRIs. Use iri_to_uri:
from werkzeug.urls import iri_to_uri
iri_to_uri(request.url)
From werkzeug/wrappers.py:
"""
...
Note that the string returned might contain unicode characters as the
representation is an IRI not an URI. If you need an ASCII only
representation you can use the :func:`~werkzeug.urls.iri_to_uri`
function:
>>> from werkzeug.urls import iri_to_uri
>>> iri_to_uri(get_current_url(env))
'http://localhost/script/?param=foo'
...
"""
One of the nice things about flask and werkzeug is that you can always follow things through in the source code.
You mean %XX escapes?
from urllib.parse import quote
quote(url)
I have a flask view which returns some JSON formatted data:
def myview():
entities = get_my_entities()
return jsonify({'entities': entities})
entities if a list of dictionaries; in each dictionary there is a value like http://example.com/get/<user_id>/12345678 where <user_id> is a placeholder where the user should insert an indentifier that that have been given (and which should not appear in the JSON result).
The problem is, the <user_id> gets escaped and appears as %3Cuser_id%3E. Is there a way to stop the characters getting escaped?
Thanks to Martijn. I'm using url_for to build the URLs, and its doing the escaping.
How do I pass a python list of JSON blobs to a django template so i can parse it from JSON into a javascript object?
With jquery I have tried the likes of $.parseJSON('{{list_of_JSON_blobs|escapejs}}') in the template, but the "string representation" of a python list is causing syntax errors.
Doing json.dumps(list_of_JSON_blobs) doesn't work either as it stringfys the already serialised JSON blobs.
Currently I am doing dumps( [loads(blob) for blob in list_of_JSON_blobs]) but this is obviously not the optimal method!
worked it out:
use join, and encapsulate the resulting string in paren
'[' + ','.join(list_of_JSON_blobs) + ']'