dane-server 0.2.2

Back-end for the Distributed Annotation 'n' Enrichment (DANE) system

DANE-server

DANE-server is the back-end component of DANE and takes care of task routing as well as the (meta)data storage. A task submitted to DANE-server is registered in a database, and then its .run() function is called. Running a task involves assigning it to a worker via a message queue.

A specific task is run by publishing the task to a RabbitMQ Topic Exchange, on this exchange the task is routed based on its Task Key. The task key corresponds to the binding_key of a worker, and each worker with this binding_key listens to a shared queue. Once a worker is available it will take the next task from the queue and process it.

DANE-server depends on the DANE package for the logic of how to iterate over tasks, and how to interpret a task in general.

Installation

DANE-server has been tested with Python 3 and is installable through pip:

pip install dane-server

Besides the python base, the DANE-server also relies on an Elasticsearch server (version 7.9) for storage, and RabbitMQ (tested with version 3.7) for messaging.

After installing all dependencies it is necessary to configure the DANE server, how to do this is described here: https://dane.readthedocs.io/en/latest/intro.html#configuration

The base config for DANE-server consists of the following parameters, which you might want to overwrite:

LOGGING: 
    DIR: "./dane-server-logs/"
    LEVEL: "DEBUG"
DANE_SERVER:
    TEMP_FOLDER: "/home/DANE/DANE-data/TEMP/"
    OUT_FOLDER: "/home/DANE/DANE-data/OUT/"

Usage

NOTE: DANE-server is still in development, as such authorisation (amongst other featueres) has not yet been added. Use at your own peril.

Run the DANE-server server as follows (this starts a Gunicorn HTTP server):

dane-server

If no errors occur then this should start a Flask server (at port 5500) which will handle API requests, and in the background the server will handle interaction with the DB and RabbitMQ.

API

DANE-server can be interacted with via a small API that supports a small number of essential calls:

/DANE/document/

Via POST a new document can be submitted. It expects a JSON object which is a serialised document specification.

/DANE/document/<doc_id>

Get information about an existing document.

/DANE/document/<doc_id>/tasks

Get information about the tasks assigned to this document

/DANE/document/<doc_id>/delete

Deletes the document

/DANE/search/<target_id>/<creator_id>

Return the _id's for all documents that have this target_id and creator_id

/DANE/task/

Via POST a new task can be submitted. It expects a JSON object which is a serialised task specification.

/DANE/task/<task_id>

Get information about this task

/DANE/task/<task_id>/retry

This will cause the DANE-server to retry this task.

/DANE/task/<task_id>/forceretry

This will force the DANE-server to retry this task, even if it completed successfully or is already queued.

/DANE/task/<task_id>/reset

Reset the task state to 201

/DANE/task/inprogress

Returns a list of _id's for in progress tasks, or tasks which have errored.

Examples

Examples of how to work with DANE can be found at: https://dane.readthedocs.io/en/latest/examples.html