Mock sample for your project: Zalando Shop API

A product library is a representation of all the items that can be
displayed, put in a shopping cart and sold to a customer. Items may be
either producs or discounts.
A product is a synthetic construct, wrapping one or more variants (which is
the actual item being sold) Variants expresses different variations of
properties such as for example price, size or color. A discount will reduce
the total amount charged in a shopping cart. It can be used per item line,
or on the whole cart. It may reduce the affected amount by a percentage, or
by a fixed amount.
Together, the above types of entities makes up a complete library. The
library can be fetched as a whole through the library endpoint, where each
consecutive change applied to the library is available. Once the full
library is retrieved, only later events needs to be fetched to keep the
client up to date with the server
All path patterns "/organizations/{organizationUuid}/" can be replaced
with "/organizations/self/" for convenience as all endpoints are for
authorized users.

The Account API gives sellers the ability to configure their eBay seller accounts, including the seller's policies (the Fulfillment Policy, Payment Policy, and Return Policy), opt in and out of eBay seller programs, configure sales tax tables, and get account information. For details on the availability of the methods in this API, see Account API requirements and restrictions.

dropX.io API provides programmatic access to the e-commerce intelligence data.

Service for providing information to sellers about their listings being non-compliant, or at risk for becoming non-compliant, against eBay listing policies.

Documentation of the Billbee REST API to connect a Billbee account to external aplications.
Endpoint
The Billbee API endpoint base url is https://app.billbee.io/api/v1
Activation
You have to enable the API in the settings of your Billbee account. In addition you need a Billbee API Key identifying the application you develop. To get an API key, send a mail to [email protected] and send us a short note about what you are building.
Authorization & security
Because you can access private data with the Billbee API, every request has to be sent over https and must
Contain a valid API Key identifying the application/developer. It has to be sent as the HTTP header X-Billbee-Api-Key
Contain a valid user login with billbee username and api password in form of a basic auth HTTP header
Throttling
Each endpoint has a throttle of max 2 requests per second per combination of API Key and Billbee user.
When you exceed these 2 calls, the API will return a HTTP 429 status code

API2Cart

The Analytics API retrieves call-limit data and the quotas that are set for the RESTful APIs and their associated resources. Responses from calls made to getRateLimits and getUerRateLimits include a list of the applicable resources and the "call limit", or quota, that is set for each resource. In addition to quota information, the response also includes the number of remaining calls available before the limit is reached, the time remaining before the quota resets, and the length of the "time window" to which the quota applies. The getRateLimits and getUserRateLimits methods retrieve call-limit information for either an application or user, respectively, and each method must be called with an appropriate OAuth token. That is, getRateLimites requires an access token generated with a client credentials grant and getUserRateLimites requires requires an access token generated with an authorization code grant. For more information, see OAuth tokens. Users can analyze the response data to see whether or not a limit might be reached, and from that determine if any action needs to be taken (such as programmatically throttling their request rate). For more on call limits, see Compatible Application Check.

This API is used to retrieve seller payouts and monetary transaction details related to those payouts.

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