SEPA-python3

Client-side libraries for the SEPA platform (Python3)

Installation and usage

Go to the folder named dist, uncompress the archive using tar, then type the usual:

python setup.py build

and

python setup.py install

(this one as root).

To use the classes you have to import them in this way:

from sepy.<the class you want to import> import *

For example, if you want to import the ConfigurationObject (used to handle JSAP and YSAP files) you have to write:

from sepy.ConfigurationObject import *

This library consists of 5 classes that can be used for different purposes:

Configurationbject: An handler class for YSAP and JSAP files
SEPAClient: A low-level class used to develop a client for SEPA
ConnectionHandler: A class for connection handling
BasicHandler: A simple example of an Handler class
Exceptions: Used to handle exceptions

Let's talk about some classes deeply:

SEPAClient

These APIs allows to develop a client for the SEPA platform using a simple interface. First of all the class SEPAClient must be initialized. Then the standard methods to interact with the broker are available.

Initialization parameters:

File : A string indicating the name with relative/full path of the YSAP or JSAP file used for configuration
logLevel : A number indicating the desired log level. Default = 40 The parameters are optional. They activate query, update, subscribe, unsubscribe methods.

Example with the mqtt.yaml file

sc = SEPAClient("mqtt.yaml") # A JSAP or YSAP file

Query and Update

These two methods (query and update) return a boolean indicating the request's success and a JSON with the results of the requests.

Query and Update parameters:

queryName/updateName : A string indicating the friendly name for the query in JSAP or YSAP file; the complete query/update string will be obtained by the parser
forcedBindings : A dictionary for in-request name replacements; by default it is empty
secure : A boolean specifying whether security mechanisms should be used or not; by default it is set as unsecure

Refering to the previous example:

queryName = "MQTT_TOPICS"
simple_query = sc.query(queryName, {})
updateName = "MQTT_MESSAGE"
forcedBindings = {"topic":"top2", "broker":"brok2", "value":"val2"}
simple_update = sc.update(updateName, forcedBindings)

Subscribe and Unsubscribe

The subscribe primitive requires a SPARQL query, an alias for the subscription, an handler class (containing the handle method) and the boolean referred to security. The unsubscribe primitive only needs to know the ID of the subscription.

YSAPObject and JSAPObject

This package supports both Semantic Application Profiles encoded with YAML or JSON. Simply create an instance of the desired class and exploits the methods to get a query/update with the provided forced bindings.

Something else?

Yes, (almost) all the code is documented through pydoc, so if you want, you can get the full documentation of attributes and methods. For example from prompt write:

python -m pydoc sepy.YSAPObject

Foreseen changes

Update tests
Correct subscribe problems
Correct secure requests
Modify YSAPObject and JSAPObject classes in order to automatically add prefixes to queries/updates
Add possibility to install the library using pip

Stay Tuned!

leobel96/SEPA-python3