Start using the library
Examples on how to use the library:
- libraries to use
- instantiate a client
- manage your handle
With this example you can start using the pyhandle library in 5 minutes.
Libraries to import
At the beginning of your python code just import
#!/usr/bin/env python
import sys
import b2handle
from pyhandle.clientcredentials import PIDClientCredentials
from pyhandle.handleclient import EUDATHandleClient
from pyhandle.handleexceptions import *
from requests.exceptions import SSLError
Instantiate your client
The first thing you have to do is to instantiate your client.
But before that you have to create a json file with the necessary data to connect to the handle server. The file uses certificates in order to authenticate with the Handle server.
{
"handle_server_url": "https://myserver.com",
"private_key": "privkey.pem",
"certificate_only": "certificate_only.pem",
"prefix": "21.11111",
"handleowner": "301:11239/ADMINUSER",
"HTTPS_verify": "True"
}
Then instantiate your client
print "Creating credentials"
cred = PIDClientCredentials.load_from_JSON('my_credentials.json')
client = PyHandleClient('rest').instantiate_with_credentials(cred)
print('PID prefix ' + cred.get_prefix())
print('Server ' + cred.get_server_URL())
Manage your handle
The Example
The example we are going to follow is to create is as follows
- Create a test handle with the name MYTEST-HANDLE with the URL http://www.example.com/1.
- Read the test handle
- Update the test handle by updating the URL to http://www.example.com/2
- Delete the handle
The data of the test handle
In this section we set the data for the test handle.
TEST_SUFFIX='MYTEST-HANDLE'
VALUE_ORIG='http://www.example.com/1'
VALUE_AFTER='http://www.example.com/2'
handle = cred.get_prefix() + '/' + TEST_SUFFIX
Now that we have the data lets start managing the handle.
Create a test handle
The creation of a handle is the first available action which is supported with register_handle
. Basic interactions
You may either register a new Handle with a unique random name (random UUID) or with a predefine value.
In this example we are creating a handle with the name TEST_SUFFIX='MYTEST-HANDLE'
# Create test
print "Creating handle " + handle
create_result = client.register_handle(handle, VALUE_ORIG)
if create_result == handle:
print "OK: Create handle successful."
else:
print "PROBLEM: Create handle returned unexpected response."
Read test handle
With the get_value_from_handle
you may retrieve a single value from a single Handle. If several entries with this key exist, the methods returns the first one. If the handle does not exist, the method will raise an exception .Basic interactions
In this example we are reading the predefined handle with key=URL.
# Read test
key = 'URL'
read_value = client.get_value_from_handle(handle, key)
if read_value == VALUE_ORIG:
print "OK: Read handle successful."
else:
print "PROBLEM: Read handle returned unexpected response."
Read full Handle record
With the retrieve_handle_record()
you may retrieve a full handle record. If several entries with this key exist, the methods returns the first one. If the handle does not exist, the method will raise an exception .Basic interactions
In this example we are reading the predefined handle with key=URL.
# Read test
read_value = client.retrieve_handle_record(handle)
if read_value != ΝΟΝΕ:
print "OK: Handle exists."
else:
print "PROBLEM: Read handle returned unexpected response."
Modify test handle
The library supports the modification of a value in the handle. Basic interactions
With modify_handle_value()
a user can modify any number of values in a specific Handle record.
In this example we are going to update the URL of the handle record with the value VALUE_AFTER
# Modify test
key = 'URL'
client.modify_handle_value(handle, **{key: VALUE_AFTER} )
get_value_result = client.get_value_from_handle(handle, key)
if get_value_result == VALUE_AFTER:
print "OK: Modify handle successful."
else:
print "CRITICAL: Modify handle value returned unexpected value."
print "Expected : " + VALUE_AFTER
print "Returned : " + get_value_result
Delete test handle
The library supports the Deletion of the handle and its handle record with the delete_function
. Basic interactions
In this example we are going to delete the handle we previously created.
# Delete test
delete_result = client.delete_handle(handle)
print "OK: Delete handle successfully."