{{define "exchanges subscription" -}}
{{template "header" .}}
# Exchange Subscriptions

Exchange Subscriptions are streams of data delivered via websocket.

GoCryptoTrader engine will subscribe automatically to configured channels.
A subset of exchanges currently support user configured channels, with the remaining using hardcoded defaults.
See configuration Features.Subscriptions for whether an exchange is configurable.

## Templating

Exchange Contributors should implement `GetSubscriptionTemplate` to return a text/template Template.

Exchanges are free to implement template caching, a map or a mono-template, inline or file templates.

The template is provided with a single context structure:
```go
  S              *subscription.Subscription
  AssetPairs     map[asset.Item]currency.Pairs
  AssetSeparator string
  PairSeparator  string
```

Subscriptions may fan out many channels for assets and pairs, to support exchanges which require individual subscriptions.  
To allow the template to communicate how to handle its output it should use the provided separators:
- AssetSeparator should be added at the end of each section related to assets
- PairSeparator should be added at the end of each pair

We use separators like this because it allows mono-templates to decide at runtime whether to fan out.

See exchanges/subscription/testdata/subscriptions.tmpl for an example mono-template showcasing various features

Templates do not need to worry about joining around separators; Trailing separators will be stripped automatically.

{{template "contributions"}}
{{template "donations" .}}
{{end}}