python-epo-ops-client 0.1.7

Client

The Client contains all the formatting and token handling logic and is what you’ll interact with mostly.

When you issue a request, the response is a requests.Response object. If response.status_code != 200 then a requests.HTTPError exception will be raised — it’s your responsibility to handle those exceptions if you want to. The one case that’s handled by the RegisteredClient is when its access token has expired: in this case, the client will automatically handle the HTTP 400 status and renew the token.

Note that the Client does not attempt to interpret the data supplied by OPS, so it’s your responsibility to parse the XML or JSON payload for your own purpose.

The following custom exceptions are raised for cases when OPS quotas are exceeded, they are all in the epo_ops.exceptions module and are subclasses of requests.HTTPError, and therefore offer the same behaviors:

• AnonymousQuotaPerMinuteExceeded

• AnonymousQuotaPerDayExceeded

• IndividualQuotaPerHourExceeded

• RegisteredQuotaPerWeekExceeded

Again, it’s up to you to parse the response and decide what to do.

Currently the Client knows how to issue request for the following services:

See the OPS guide for more information on how to use each service.

Please submit pull requests for the following services by enhancing the epo_ops.api.Client class:

• Legal service

• Number service

• Images retrieval

• Bulk operations

Middleware

All requests and responses are passed through each middleware object listed in client.middlewares. Requests are processed in the order listed, and responses are processed in the reverse order.

Each middleware should subclass middlewares.Middleware and implement the process_request and process_response methods.

There are two middleware classes out of the box: Throttler and Dogpile. Throttler is in charge of the OPS throttling rules and will delay requests accordingly. Dogpile is an optional cache which will cache all HTTP status 200, 404, 405, and 413 responses.

By default, only the Throttler middleware is enabled, if you want to enable caching:

import epo_ops

middlewares = [
    epo_ops.middlewares.Dogpile(),
    epo_ops.middlewares.Throttler(),
]
registered_client = epo_ops.RegisteredClient(
    key='key',
    secret='secret',
    middlewares=middlewares,
)

Note that caching middleware should be first in most cases.