Im working on a small project of retrieving information about books from the Google Books API using Python 3. For this i make a call to the API, read out the variables and store those in a list. For a search like "linkedin" this works perfectly. However when i enter "Google", it reads the second title from the JSON input. How can this happen?
Please find my code below (Google_Results is the class I use to initialize the variables):
import requests
def Book_Search(search_term):
parms = {"q": search_term, "maxResults": 3}
r = requests.get(url="https://www.googleapis.com/books/v1/volumes", params=parms)
print(r.url)
results = r.json()
i = 0
for result in results["items"]:
try:
isbn13 = str(result["volumeInfo"]["industryIdentifiers"][0]["identifier"])
isbn10 = str(result["volumeInfo"]["industryIdentifiers"][1]["identifier"])
title = str(result["volumeInfo"]["title"])
author = str(result["volumeInfo"]["authors"])[2:-2]
publisher = str(result["volumeInfo"]["publisher"])
published_date = str(result["volumeInfo"]["publishedDate"])
description = str(result["volumeInfo"]["description"])
pages = str(result["volumeInfo"]["pageCount"])
genre = str(result["volumeInfo"]["categories"])[2:-2]
language = str(result["volumeInfo"]["language"])
image_link = str(result["volumeInfo"]["imageLinks"]["thumbnail"])
dict = Google_Results(isbn13, isbn10, title, author, publisher, published_date, description, pages, genre,
language, image_link)
gr.append(dict)
print(gr[i].title)
i += 1
except:
pass
return
gr = []
Book_Search("Linkedin")
I am a beginner to Python, so any help would be appreciated!
It does so because there is no publisher entry in volumeInfo of the first entry, thus it raises a KeyError and your except captures it. If you're going to work with fuzzy data you have to account for the fact that it will not always have the expected structure. For simple cases you can rely on dict.get() and its default argument to return a 'valid' default entry if an entry is missing.
Also, there are a few conceptual problems with your function - it relies on a global gr which is bad design, it shadows the built-in dict type and it captures all exceptions guaranteeing that you cannot exit your code even with a SIGINT... I'd suggest you to convert it to something a bit more sane:
def book_search(search_term, max_results=3):
results = [] # a list to store the results
parms = {"q": search_term, "maxResults": max_results}
r = requests.get(url="https://www.googleapis.com/books/v1/volumes", params=parms)
try: # just in case the server doesn't return valid JSON
for result in r.json().get("items", []):
if "volumeInfo" not in result: # invalid entry - missing volumeInfo
continue
result_dict = {} # a dictionary to store our discovered fields
result = result["volumeInfo"] # all the data we're interested is in volumeInfo
isbns = result.get("industryIdentifiers", None) # capture ISBNs
if isinstance(isbns, list) and isbns:
for i, t in enumerate(("isbn10", "isbn13")):
if len(isbns) > i and isinstance(isbns[i], dict):
result_dict[t] = isbns[i].get("identifier", None)
result_dict["title"] = result.get("title", None)
authors = result.get("authors", None) # capture authors
if isinstance(authors, list) and len(authors) > 2: # you're slicing from 2
result_dict["author"] = str(authors[2:-2])
result_dict["publisher"] = result.get("publisher", None)
result_dict["published_date"] = result.get("publishedDate", None)
result_dict["description"] = result.get("description", None)
result_dict["pages"] = result.get("pageCount", None)
genres = result.get("authors", None) # capture genres
if isinstance(genres, list) and len(genres) > 2: # since you're slicing from 2
result_dict["genre"] = str(genres[2:-2])
result_dict["language"] = result.get("language", None)
result_dict["image_link"] = result.get("imageLinks", {}).get("thumbnail", None)
# make sure Google_Results accepts keyword arguments like title, author...
# and make them optional as they might not be in the returned result
gr = Google_Results(**result_dict)
results.append(gr) # add it to the results list
except ValueError:
return None # invalid response returned, you may raise an error instead
return results # return the results
Then you can easily retrieve as much info as possible for a term:
gr = book_search("Google")
And it will be far more tolerant of data omissions, provided that your Google_Results type makes most of the entries optional.
Following #Coldspeed's recommendation it became clear that missing information in the JSON file caused the exception to run. Since I only had a "pass" statement there it skipped the entire result. Therefore I will have to adapt the "Try and Except" statements so errors do get handled properly.
Thanks for the help guys!
Related
I'm fairly new to Python so bear with me please.
I have a function that takes two parameters, an api response and an output object, i need to assign some values from the api response to the output object:
def map_data(output, response):
try:
output['car']['name'] = response['name']
output['car']['color'] = response['color']
output['car']['date'] = response['date']
#other mapping
.
.
.
.
#other mapping
except KeyError as e:
logging.error("Key Missing in api Response: %s", str(e))
pass
return output
Now sometimes, the api response is missing some keys i'm using to generate my output object, so i used the KeyError exception to handle this case.
Now my question is, in a case where the 'color' key is missing from the api response, how can i catch the exception and continue to the line after it output['car']['date'] = response['date'] and the rest of the instructions.
i tried the pass instruction but it didn't have any affect.
Ps: i know i can check the existence of the key using:
if response.get('color') is not None:
output['car']['color'] = response['color']
and then assign the values but seeing that i have about 30 values i need to map, is there any other way i can implement ? Thank you
A few immediate ideas
(FYI - I'm not going to explain everything in detail - you can check out the python docs for more info, examples etc - that will help you learn more, rather than trying to explain everything here)
Google 'python handling dict missing keys' for a million methods/ideas/approaches - it's a common use case!
Convert your response dict to a defaultdict. In that case you can have a default value returned (eg None, '', 'N/A' ...whatever you like) if there is no actual value returned.
In this case you could do away with the try and every line would be executed.
from collections import defaultdict
resp=defaultdict(lambda: 'NA', response)
output['car']['date'] = response['date'] # will have value 'NA' if 'date' isnt in response
Use the in syntax, perhaps in combination with a ternary else
output['car']['color'] = response['color'] if 'color' in response
output['car']['date'] = response['date'] if 'date' in response else 'NA'
Again you can do away with the try block and every line will execute.
Use the dictionary get function, which allows you to specify a default if there is no value for that key:
output['car']['color'] = response.get('car', 'no car specified')
You can create a utility function that gets the value from the response and if the value is not found, it returns an empty string. See example below:
def get_value_from_response_or_null(response, key):
try:
value = response[key]
return value
except KeyError as e:
logging.error("Key Missing in api Response: %s", str(e))
return ""
def map_data(output, response):
output['car']['name'] = get_value_from_response_or_null(response, 'name')
output['car']['color'] = get_value_from_response_or_null(response, 'color')
output['car']['date'] = get_value_from_response_or_null(response, 'date')
# other mapping
# other mapping
return output
I am trying to use two Google API calls to get a restaurant's price_level and phone number.
First, looping through
for restaurant in name:
find_place_url = "https://maps.googleapis.com/maps/api/place/findplacefromtext/json?"
# use separate parameter dictionary b.c. findplace and findplacedetail have diff field.
find_place_param ={}
find_place_param["input"] = restaurant
find_place_param["inputtype"] = "textquery"
find_place_param["key"] = google_key
# get place_id then use it to get phone number
a = requests.get(find_place_url, parameters).json()
this is first findplace api used to grab place_id for given restaurant. It will look like:
{'candidates': [{'place_id': 'ChIJdTDCTdT4cUgRqxush2XhgnQ'}], 'status': 'OK'}
if given restaurant has proper place_id or else it will give:
{'candidates': [], 'status': 'ZERO_RESULTS'}
now this is all of my code: from here I grab place_id however put it in try and except because as stated above status is either zero or ok. But even if I go pass except it will run find_place_detail api call which requires place_id thus it fails. How can I skip last block of code if I do not receive place_id?
price_level2 = []
phone_number = []
for restaurant in name:
find_place_url = "https://maps.googleapis.com/maps/api/place/findplacefromtext/json?"
# use separate parameter dictionary b.c. findplace and findplacedetail have diff field.
find_place_param ={}
find_place_param["input"] = restaurant
find_place_param["inputtype"] = "textquery"
find_place_param["key"] = google_key
# get place_id then use it to get phone number
a = requests.get(find_place_url, parameters).json()
print(a)
# adding it to original parameter. since only this and findplace parameter has to be different.
try:
parameters["place_id"] = a["candidates"][0]["place_id"]
except:
print("Phone number not available")
phone_number.append(None)
# passing in fields of our interest
parameters["fields"] = "name,price_level,formatted_phone_number"
find_place_detail_url ="https://maps.googleapis.com/maps/api/place/details/json?"
b = requests.get(find_place_detail_url, parameters).json()
phone_number.append(b["result"]["formatted_phone_number"])
price_level2.append(b["result"]['price_level'])
You can use an else clause:
try:
parameters["place_id"] = a["candidates"][0]["place_id"]
except KeyError:
print("Phone number not available")
phone_number.append(None)
else:
parameters["fields"] = "name,price_level,formatted_phone_number"
find_place_detail_url ="https://maps.googleapis.com/maps/api/place/details/json?"
b = requests.get(find_place_detail_url, parameters).json()
...
Also, your except clause should be more specific (I guess the case you're trying to catch is a KeyError). For more information on exception handling in Python, see the documentation.
I keep getting the following error when trying to parse some json:
Traceback (most recent call last):
File "/Users/batch/projects/kl-api/api/helpers.py", line 37, in collect_youtube_data
keywords = channel_info_response_data['items'][0]['brandingSettings']['channel']['keywords']
KeyError: 'brandingSettings'
How do I make sure that I check my JSON output for a key before assigning it to a variable? If a key isn’t found, then I just want to assign a default value. Code below:
try:
channel_id = channel_id_response_data['items'][0]['id']
channel_info_url = YOUTUBE_URL + '/channels/?key=' + YOUTUBE_API_KEY + '&id=' + channel_id + '&part=snippet,contentDetails,statistics,brandingSettings'
print('Querying:', channel_info_url)
channel_info_response = requests.get(channel_info_url)
channel_info_response_data = json.loads(channel_info_response.content)
no_of_videos = int(channel_info_response_data['items'][0]['statistics']['videoCount'])
no_of_subscribers = int(channel_info_response_data['items'][0]['statistics']['subscriberCount'])
no_of_views = int(channel_info_response_data['items'][0]['statistics']['viewCount'])
avg_views = round(no_of_views / no_of_videos, 0)
photo = channel_info_response_data['items'][0]['snippet']['thumbnails']['high']['url']
description = channel_info_response_data['items'][0]['snippet']['description']
start_date = channel_info_response_data['items'][0]['snippet']['publishedAt']
title = channel_info_response_data['items'][0]['snippet']['title']
keywords = channel_info_response_data['items'][0]['brandingSettings']['channel']['keywords']
except Exception as e:
raise Exception(e)
You can either wrap all your assignment in something like
try:
keywords = channel_info_response_data['items'][0]['brandingSettings']['channel']['keywords']
except KeyError as ignore:
keywords = "default value"
or, let say, use .has_key(...). IMHO In your case first solution is preferable
suppose you have a dict, you have two options to handle the key-not-exist situation:
1) get the key with default value, like
d = {}
val = d.get('k', 10)
val will be 10 since there is not a key named k
2) try-except
d = {}
try:
val = d['k']
except KeyError:
val = 10
This way is far more flexible since you can do anything in the except block, even ignore the error with a pass statement if you really don't care about it.
How do I make sure that I check my JSON output
At this point your "JSON output" is just a plain native Python dict
for a key before assigning it to a variable? If a key isn’t found, then I just want to assign a default value
Now you know you have a dict, browsing the official documention for dict methods should answer the question:
https://docs.python.org/3/library/stdtypes.html#dict.get
get(key[, default])
Return the value for key if key is in the dictionary, else default. If default is not given, it defaults to None, so that this method never raises a KeyError.
so the general case is:
var = data.get(key, default)
Now if you have deeply nested dicts/lists where any key or index could be missing, catching KeyErrors and IndexErrors can be simpler:
try:
var = data[key1][index1][key2][index2][keyN]
except (KeyError, IndexError):
var = default
As a side note: your code snippet is filled with repeated channel_info_response_data['items'][0]['statistics'] and channel_info_response_data['items'][0]['snippet'] expressions. Using intermediate variables will make your code more readable, easier to maintain, AND a bit faster too:
# always set a timeout if you don't want the program to hang forever
channel_info_response = requests.get(channel_info_url, timeout=30)
# always check the response status - having a response doesn't
# mean you got what you expected. Here we use the `raise_for_status()`
# shortcut which will raise an exception if we have anything else than
# a 200 OK.
channel_info_response.raise_for_status()
# requests knows how to deal with json:
channel_info_response_data = channel_info_response.json()
# we assume that the response MUST have `['items'][0]`,
# and that this item MUST have "statistics" and "snippets"
item = channel_info_response_data['items'][0]
stats = item["statistics"]
snippet = item["snippet"]
no_of_videos = int(stats.get('videoCount', 0))
no_of_subscribers = int(stats.get('subscriberCount', 0))
no_of_views = int(stats.get('viewCount', 0))
avg_views = round(no_of_views / no_of_videos, 0)
try:
photo = snippet['thumbnails']['high']['url']
except KeyError:
photo = None
description = snippet.get('description', "")
start_date = snippet.get('publishedAt', None)
title = snippet.get('title', "")
try:
keywords = item['brandingSettings']['channel']['keywords']
except KeyError
keywords = ""
You may also want to learn about string formatting (contatenating strings is quite error prone and barely readable), and how to pass arguments to requests.get()
I am getting JIRA data using the following python code,
how do I store the response for more than one key (my example shows only one KEY but in general I get lot of data) and print only the values corresponding to total,key, customfield_12830, summary
import requests
import json
import logging
import datetime
import base64
import urllib
serverURL = 'https://jira-stability-tools.company.com/jira'
user = 'username'
password = 'password'
query = 'project = PROJECTNAME AND "Build Info" ~ BUILDNAME AND assignee=ASSIGNEENAME'
jql = '/rest/api/2/search?jql=%s' % urllib.quote(query)
response = requests.get(serverURL + jql,verify=False,auth=(user, password))
print response.json()
response.json() OUTPUT:-
http://pastebin.com/h8R4QMgB
From the the link you pasted to pastebin and from the json that I saw, its a you issues as list containing key, fields(which holds custom fields), self, id, expand.
You can simply iterate through this response and extract values for keys you want. You can go like.
data = response.json()
issues = data.get('issues', list())
x = list()
for issue in issues:
temp = {
'key': issue['key'],
'customfield': issue['fields']['customfield_12830'],
'total': issue['fields']['progress']['total']
}
x.append(temp)
print(x)
x is list of dictionaries containing the data for fields you mentioned. Let me know if I have been unclear somewhere or what I have given is not what you are looking for.
PS: It is always advisable to use dict.get('keyname', None) to get values as you can always put a default value if key is not found. For this solution I didn't do it as I just wanted to provide approach.
Update: In the comments you(OP) mentioned that it gives attributerror.Try this code
data = response.json()
issues = data.get('issues', list())
x = list()
for issue in issues:
temp = dict()
key = issue.get('key', None)
if key:
temp['key'] = key
fields = issue.get('fields', None)
if fields:
customfield = fields.get('customfield_12830', None)
temp['customfield'] = customfield
progress = fields.get('progress', None)
if progress:
total = progress.get('total', None)
temp['total'] = total
x.append(temp)
print(x)
I'm writing a python scraper code for OpenData and I have one question about : how to check if all values aren't filled in site and if it is null change value to null.
My scraper is here.
Currently I'm working on it to optimalize.
My variables now look like:
evcisloval = soup.find_all('td')[3].text.strip()
prinalezival = soup.find_all('td')[5].text.strip()
popisfaplnenia = soup.find_all('td')[7].text.replace('\"', '')
hodnotafaplnenia = soup.find_all('td')[9].text[:-1].replace(",", ".").replace(" ", "")
datumdfa = soup.find_all('td')[11].text
datumzfa = soup.find_all('td')[13].text
formazaplatenia = soup.find_all('td')[15].text
obchmenonazov = soup.find_all('td')[17].text
sidlofirmy = soup.find_all('td')[19].text
pravnaforma = soup.find_all('td')[21].text
sudregistracie = soup.find_all('td')[23].text
ico = soup.find_all('td')[25].text
dic = soup.find_all('td')[27].text
cislouctu = soup.find_all('td')[29].text
And Output :
scraperwiki.sqlite.save(unique_keys=["invoice_id"],
data={ "invoice_id":number,
"invoice_price":hodnotafaplnenia,
"evidence_no":evcisloval,
"paired_with":prinalezival,
"invoice_desc":popisfaplnenia,
"date_received":datumdfa,
"date_payment":datumzfa,
"pay_form":formazaplatenia,
"trade_name":obchmenonazov,
"trade_form":pravnaforma,
"company_location":sidlofirmy,
"court":sudregistracie,
"ico":ico,
"dic":dic,
"accout_no":cislouctu,
"invoice_attachment":urlfa,
"invoice_url":url})
I googled it but without success.
First, write a configuration dict of your variables in the form:
conf = {'evidence_no': (3, str.strip),
'trade_form': (21, None),
...}
i.e. key is the output key, value is a tuple of id from soup.find_all('td') and of an optional function that has to be applied to the result, None otherwise. You don't need those Slavic variable names that may confuse other SO members.
Then iterate over conf and fill the data dict.
Also, run soup.find_all('td') before the loop.
tds = soup.find_all('td')
data = {}
for name, (num, func) in conf.iteritems():
text = tds[num].text
# replace text with None or "NULL" or whatever if needed
...
if func is None:
data[name] = text
else:
data[name] = func(text)
This will remove a lot of duplicated code. Easier to maintain.
Also, I am not sure the strings "NULL" are the best way to write missing data. Doesn't sqlite support Python's real None objects?
Just read your attached link, and it seems what you want is
evcisloval = soup.find_all('td')[3].text.strip() or "NULL"
But be careful. You should only do this with strings. If the part before or is either empty or False or None, or 0, they will all be replaced with "NULL"