Developer Guide

The developer guide describes how to develop apps with django-esi.

Usage in views

Single token

When views require a token, wrap with the token_required decorator and accept a token arg:

from esi.decorators import token_required

@token_required(scopes="esi-characters.read_medals.v1")
def my_view(request, token):
    # my code

This will prompt the user to either select a token from their current ones, or if none exist create a new one via SSO.

To specify scopes, add either a list of names or a space-delimited string:

@token_required(scopes=['esi-location.read_ship_type.v1', 'esi-location.read_location.v1'])
@token_required(scopes='esi-location.read_ship_type.v1 esi-location.read_location.v1')

New token

To require a new token, such as for logging in, add the new argument:

@token_required(new=True)

Multiple tokens

To request all of a user’s tokens which have the required scopes, wrap instead with the tokens_required decorator and accept a tokens arg:

@tokens_required(scopes='esi-location.read_ship_type.v1')
def my_view(request, tokens):
    # my code

This skips prompting for token selection and instead passes that responsibility to the view. Tokens are provided as a queryset.

Single use token

It is also possible to request a token for single use. Single use tokens do not require a user to be logged in and are only available to the current view.

from esi.decorators import single_use_token

@single_use_token(scopes=['publicData'])
my_view(request, token):
    # my code

Accessing ESI

django-esi provides a convenience wrapper around the bravado SwaggerClient.

New approach for getting a client object

All access to ESI happens through a client object that is automatically generated for you and contains all of ESI’s routes. The new and recommended way of getting that client object is through a single provider instance from the EsiClientProvider class.

The new provider approach has two main advantages: First, creating a new client is slow (e.g. can takes up to 5 seconds). So, for maximum performance you want to avoid creating multiple clients in your app. Using the provider automatically ensures this.

Second, the previous approach of creating multiple clients can cause memory leaks. Especially when used in concurrent environment (e.g. threads or celery tasks), where each worker is creating it’s own client.

Example for creating a provider

The provider needs to be instantiated at “import time”, so it must be defined in the global scope of a module.

from esi.clients import EsiClientProvider

# create your own provider
esi = EsiClientProvider()

def main():
    # do stuff with your provider

If you need to use the provider in several module than a good pattern is to define it in it’s own module, e.g. providers.py, and then import the provider instance into all other modules that need an ESI client.

Using public endpoints

Here is a complete example how to use a public endpoint. Public endpoints can in general be accessed without any authentication.

from esi.clients import EsiClientProvider

# create your own provider
esi = EsiClientProvider()

def main():
    # call the endpoint
    result = esi.client.Status.get_status().results()

    # ... do stuff with the data
    print(result)

Using authenticated endpoints

Non-public endpoints will require authentication. You will therefore need to provide a valid access token with your request.

The following example shows how to retrieve data from a non-public endpoint using an already existing token in your database.

results() vs. result()

django-esi offers two similar methods for requesting the response from an endpoint: results() and result(). Here is a quick overview how they differ:

Topic	results()	result()
Paging	Automatically returns all pages if they are more than one	Only returns the fist page or the requested page (when specified with page parameter)
Headers	Returns the headers for the last retrieved page	Returns the headers for the first / requested page
Backwards compatibility	New feature in 2.0	Works mostly as in 1.6

In general we recommend to use results(), so you don’t have to worry about paging. Nevertheless, result() gives you more direct control of your API request and has it’s uses, e.g when you are only interested in the first page and do not want to wait for all pages to download from the API.

Getting localized responses from ESI

Some ESI endpoints support localization, which means they are able to return the content localized in one of the supported languages.

To retrieve localized content just provide the language code in your request. The following example will retrieve the type info for the Svipul in Korean:

result = (
    esi.client.Universe
    .get_universe_types_type_id(type_id=30004984, language='ko')
    .results()
)

A common use case it to retrieve localizations for all languages for the current request. For this django-esi provides the convenience method results_localized(). It substitutes results() and will return the response in all officially supported languages by default.

result = (
    esi.client.Universe
    .get_universe_types_type_id(type_id=30004984)
    .results_localized()
)

Alternatively you can pass the list of languages (as language code) that you are interested in:

result = (
    esi.client.Universe
    .get_universe_types_type_id(type_id=30004984)
    .results_localized(languages=['ko', 'de'])
)

Specifying resource versions

As explained on the EVE Developers Blog, it’s best practice to call a specific version of the resource and allow the ESI router to map it to the correct route, being legacy, latest or dev.

Client initialization begins with a base swagger spec. By default this is the version defined in settings (ESI_API_VERSION), but can be overridden with an extra argument to the factory:

client = esi_client_factory(version='v4')

Only resources with the specified version number will be available. For instance, if you specify v4 but Universe does not have a v4 version, it will not be available to that specific client. Only legacy, latest and dev are guaranteed to have all resources available.

Individual resources are versioned and can be accessed by passing additional arguments to the factory:

client = esi_client_factory(Universe='v1', Character='v3')

A list of available resources is available on the EVE Swagger Interface browser. If the resource is not available with the specified version, an AttributeError will be raised.

This version of the resource replaces the resource originally initialized. If the requested base version does not have the specified resource, it will be added.

Note that only one old revision of each resource is kept available through the legacy route. Keep an eye on the deployment timeline for resource updates.

User Agent header

CCP asks developers to provide a “good User-Agent header” with all requests to ESI, so that CCP can identify which app the request belongs to and is able to contact the server owner running the app in case of any issues. This requirement is specified in the CCP’s Developer Guidelines and detailed in the ESI guidelines.

Django-esi provides two features for setting the User-Agent header:

Application Info

You configure the User-Agent to represent your application by setting the app_info_text parameter when creating a client with EsiClientProvider or with esi_client_factory.

There is no official format for the User-Agent, but we would suggest including the distribution name (same as e.g. in your setup.py) and current version of your application like so:

"my-app v1.0.0"

Here is a complete example for defining an application string with your app:

from esi.clients import EsiClientProvider

esi = EsiClientProvider(app_info_text="my-app v1.0.0")

Hint

Spaces are used as delimiter in the User Agent, so your application name should not include any.

Note

If you do not define an application string, the application string used will be "django-esi vX.Y.Z".

Contact email

To enable CCP to contact the maintainer of a server that is using ESI it is important to specify a contact email. This can be done through the setting ESI_USER_CONTACT_EMAIL.

Example:

ESI_USER_CONTACT_EMAIL = "admin@example.com"

In case you are not hosting the app yourself, we would recommend including this setting in the installation guide for your app.

Cleaning the database

Two tasks are available:

cleanup_callbackredirect removes all CallbackRedirect models older than a specified age (in seconds). Default is 300.
cleanup_token checks all Token models, and if expired, attempts to refresh. If expired and cannot refresh, or fails to refresh, the model is deleted.

To schedule these automatically with celerybeat, add them to your settings.py CELERYBEAT_SCHEDULE dict like so:

from celery.schedules import crontab

CELERYBEAT_SCHEDULE = {
    ...
    'esi_cleanup_callbackredirect': {
        'task': 'esi.tasks.cleanup_callbackredirect',
        'schedule': crontab(hour='*/4'),
    },
    'esi_cleanup_token': {
        'task': 'esi.tasks.cleanup_token',
        'schedule': crontab(day_of_month='*/1'),
    },
}

Recommended intervals are four hours for callback redirect cleanup and daily for token cleanup (token cleanup can get quite slow with a large database, so adjust as needed). If your app does not require background token validation, it may be advantageous to not schedule the token cleanup task, instead relying on the validation check when using @token_required decorators or adding .require_valid() to the end of a query.

Advanced Features

Using a local spec file

Specifying resource versions introduces one major problem for shared code: not all resources nor all their operations are available on any given version. This can be addressed by shipping a copy of the versioned latest spec with your app. This is the preferred method for deployment.

To build a client using this local spec, pass an additional parameter spec_file which contains the path to your local swagger.json:

from esi.clients import EsiClientProvider

esi = EsiClientProvider(spec_file='/path/to/swagger.json')

For example, a swagger.json in the current file’s directory would look like:

import os
from esi.clients import EsiClientProvider

SWAGGER_SPEC = os.path.join(os.path.dirname(os.path.abspath(__file__)), 'swagger.json')
esi = EsiClientProvider(spec_file=SWAGGER_SPEC)

If a spec_file is specified all other versioning is unavailable: ensure you ship a spec with resource versions your app can handle.

Getting Response Data

Sometimes you may want to also get the internal response object from an ESI response. For example to inspect the response header. For that simply set the request_config.also_return_response to True and then call the endpoint. This works in the same way for both .result() and .results()

from esi.clients import EsiClientProvider
from esi.models import Token

# create your own provider
esi = EsiClientProvider()

def main():
    character_id = 1234
    required_scopes = ['esi-characters.read_notifications.v1']

    # get a token
    token = Token.get_token(character_id, required_scopes)

    # call the endpoint but don't request data.
    operation = esi.client.Character.get_characters_character_id_notifications(
        character_id = character_id,
        token = token.valid_access_token()
    )

    # set to get the response as well
    operation.request_config.also_return_response = True

    # get your data
    notifications, response = operation.results()

    # ... do stuff with the data
    print(response.headers['Expires'])

Accessing alternate data sources

ESI data source can also be specified during client creation:

from esi.clients import EsiClientProvider
from esi.models import Token

# create your own provider
esi = EsiClientProvider(datasource='tranquility')

Currently the only available data source is tranquility, which is also the default The previously available datasource singularity is no longer available.

Exploring ESI Endpoints

The builtin Django shell allows you to explore the EVE ESI endpoints via django-esi, making it an easy way to find what methods are available for consumption.

Prerequisites

Prior to using the Django shell to explore django-esi, you must first install and configure django-esi in the Django project.

Getting Started

Open up a command line and navigate to the Django folder containing manage.py.

$ python manage.py shell
>>> from esi.clients import esi_client_factory
>>> c = esi_client_factory()
>>> print(dir( c ))

The above commands in the Django shell should show something like this:

['Alliance',
'Assets',
'Bookmarks',
...
'Wallet',
'Wars']

Further Uses

Once it’s working, you can explore further endpoints just by adding to the c variable.

>>> print(dir(c.Universe))
'get_universe_ancestries',
'get_universe_asteroid_belts_asteroid_belt_id',
...
'post_universe_ids',
'post_universe_names']