# Understanding Responses

## Comparison to OpenActive Source Data

The imin responses are compatible with the [OpenActive modelling specification](https://www.openactive.io/modelling-opportunity-data/), and even pass using the [OpenActive validator](https://validator.openactive.io/).

## **Augmented Fields**

The imin search results have additional properties added to them for convenience. For example `imin:fullAddress` reliably contains the full address, regardless of the components present. All the fields in the response can be found documented in the [API Reference](https://docs.imin.co/platform-products/search/imin-events-api/api-reference).

## `imin:totalItems`

`imin:totalItems` appears in all Search API calls across the Events, Facilities and Places APIs. It is the number of items that match the search request across all pages and may be an approximation.

When there is a small number of results (e.g. just one page of results), this number will be precisely accurate and reflect the exact number of items that match the search request.

However, this is not the case when there are a larger number of results. The reason for this is that our Platform will make an approximation in order to improve the performance of the search.

{% hint style="warning" %}
If you are communicating `imin:totalItems` to the end user, please note that it may be an approximation depending on the number of items returned by a search request.
{% endhint %}

## 2-week API Lookahead Window

The API will only return information about events that are due to take place within the next 14 days. This is to ensure that the amount of data returned is manageable (by reducing the `EventSeries` object size) and relevant (our research shows that the bookable window for most leisure operator members is 2 weeks in advance).

## Maximum URL Length

{% hint style="danger" %}
Each API call should be limited to a maximum of 2,048 characters.
{% endhint %}

## `null` Values and Empty Arrays

Across all of our APIs, we will remove any field if:

* The value is `null`; or
* The array is empty.

This is a general principle set out in the OpenActive Specification [here](https://openactive.io/modelling-opportunity-data/#required-and-optional-properties).

## Archiving of `EventSeries` and `FacilityUse`s

We archive `ScheduledSession`s and `Slot`s that are in the past (`startDate` < now). If an `EventSeries`' `ScheduledSession`s are all archived, the `EventSeries` will no longer appear in `By-ID` search routes. This is also the case for a `FacilityUse` when all its `Slot`s are in the past.

{% hint style="warning" %}
`EventSeries`/`FacilityUse By-ID` routes do not persist when all associated `ScheduledSession`s/`Slot`s are in the past.
{% endhint %}

## Parameters and the Number of Items Returned

The more parameters you add, the more specific you are being about what data you want the Platform to provide and so the less items an API call will return.

{% hint style="info" %}

* 0 parameters included in an API call = X thousand item&#x73;**^** returned;
* 2 parameters included in an API call = X hundred item&#x73;**^** returned.
* 6 parameters included in an API call = X hundred item&#x73;**^** returned.

**^ These numbers are for illustrative purposes only.**
{% endhint %}

## Identifying Data Sources

The data our Platform originates from a variety of organisations that publish open data, e.g. [Active Northumberland](#archiving-of-eventseries-and-facilityuses). These organisations, many of which are listed on OpenActive’s [Status Page](https://status.openactive.io/) and [Supplemental Status Page](https://docs.google.com/document/d/e/2PACX-1vShUnBhlPXyPPjSlaaMbVQClp3Pev28CCI5G8lWYwKLFd0-qyqyOLBb9kW_NX96-vH-WI5kfN6jlqiN/pub), can be identified in our API by looking at `"imin:dataSource": "identifier"`, e.g. `activenorthumberland`.

However, `identifier` may not necessarily be simply an organisation's name. This is because, over time, feeds can be deprecated and replaced by a newer versions. As a result of this, we can end up with multiple `identifier`s from the same organisation in our Platform. To distinguish between them, we include the year the new feed is released, e.g. `everyoneactive2020`.