Making a request to a RESTful API using python
PythonElasticsearchRestPython Problem Overview
I have a RESTful API that I have exposed using an implementation of Elasticsearch on an EC2 instance to index a corpus of content. I can query the search by running the following from my terminal (MacOSX):
curl -XGET 'http://ES_search_demo.com/document/record/_search?pretty=true' -d '{
"query": {
"bool": {
"must": [
{
"text": {
"record.document": "SOME_JOURNAL"
}
},
{
"text": {
"record.articleTitle": "farmers"
}
}
],
"must_not": [],
"should": []
}
},
"from": 0,
"size": 50,
"sort": [],
"facets": {}
}'
How do I turn above into a API request using python/requests
or python/urllib2
(not sure which one to go for - have been using urllib2, but hear that requests is better...)? Do I pass as a header or otherwise?
Python Solutions
Solution 1 - Python
Using requests:
import requests
url = 'http://ES_search_demo.com/document/record/_search?pretty=true'
data = '''{
"query": {
"bool": {
"must": [
{
"text": {
"record.document": "SOME_JOURNAL"
}
},
{
"text": {
"record.articleTitle": "farmers"
}
}
],
"must_not": [],
"should": []
}
},
"from": 0,
"size": 50,
"sort": [],
"facets": {}
}'''
response = requests.post(url, data=data)
Depending on what kind of response your API returns, you will then probably want to look at response.text
or response.json()
(or possibly inspect response.status_code
first). See the quickstart docs here, especially this section.
Solution 2 - Python
Using requests and json makes it simple.
- Call the API
- Assuming the API returns a JSON, parse the JSON object into a
Python dict using
json.loads
function - Loop through the dict to extract information.
Requests module provides you useful function to loop for success and failure.
if(Response.ok)
: will help help you determine if your API call is successful (Response code - 200)
Response.raise_for_status()
will help you fetch the http code that is returned from the API.
Below is a sample code for making such API calls. Also can be found in [github] 3. The code assumes that the API makes use of digest authentication. You can either skip this or use other appropriate authentication modules to authenticate the client invoking the API.
#Python 2.7.6
#RestfulClient.py
import requests
from requests.auth import HTTPDigestAuth
import json
# Replace with the correct URL
url = "http://api_url"
# It is a good practice not to hardcode the credentials. So ask the user to enter credentials at runtime
myResponse = requests.get(url,auth=HTTPDigestAuth(raw_input("username: "), raw_input("Password: ")), verify=True)
#print (myResponse.status_code)
# For successful API call, response code will be 200 (OK)
if(myResponse.ok):
# Loading the response data into a dict variable
# json.loads takes in only binary or string variables so using content to fetch binary content
# Loads (Load String) takes a Json file and converts into python data structure (dict or list, depending on JSON)
jData = json.loads(myResponse.content)
print("The response contains {0} properties".format(len(jData)))
print("\n")
for key in jData:
print key + " : " + jData[key]
else:
# If response code is not ok (200), print the resulting http error code with description
myResponse.raise_for_status()
Solution 3 - Python
So you want to pass data in body of a GET request, better would be to do it in POST call. You can achieve this by using both Requests.
Raw Request
GET http://ES_search_demo.com/document/record/_search?pretty=true HTTP/1.1
Host: ES_search_demo.com
Content-Length: 183
User-Agent: python-requests/2.9.0
Connection: keep-alive
Accept: */*
Accept-Encoding: gzip, deflate
{
"query": {
"bool": {
"must": [
{
"text": {
"record.document": "SOME_JOURNAL"
}
},
{
"text": {
"record.articleTitle": "farmers"
}
}
],
"must_not": [],
"should": []
}
},
"from": 0,
"size": 50,
"sort": [],
"facets": {}
}
Sample call with Requests
import requests
def consumeGETRequestSync():
data = '{
"query": {
"bool": {
"must": [
{
"text": {
"record.document": "SOME_JOURNAL"
}
},
{
"text": {
"record.articleTitle": "farmers"
}
}
],
"must_not": [],
"should": []
}
},
"from": 0,
"size": 50,
"sort": [],
"facets": {}
}'
url = 'http://ES_search_demo.com/document/record/_search?pretty=true'
headers = {"Accept": "application/json"}
# call get service with headers and params
response = requests.get(url,data = data)
print "code:"+ str(response.status_code)
print "******************"
print "headers:"+ str(response.headers)
print "******************"
print "content:"+ str(response.text)
consumeGETRequestSync()
Solution 4 - Python
Below is the program to execute the rest api in python-
import requests
url = 'https://url'
data = '{ "platform": { "login": { "userName": "name", "password": "pwd" } } }'
response = requests.post(url, data=data,headers={"Content-Type": "application/json"})
print(response)
sid=response.json()['platform']['login']['sessionId'] //to extract the detail from response
print(response.text)
print(sid)