A token is an arbitrary bit of text that is used to access resources. Each token has a scope that describes which resources are accessible with it. A token may be revoked at anytime and is valid for a finite duration.
The nature of required and optional auth options will depend on your provider, but generally the Username and IdentityEndpoint fields are always required. Some providers will insist on a Password instead of an APIKey, others will prefer TenantID over TenantName - so it is always worth checking before writing your implementation in Go.
{% highlight go %} import "github.com/rackspace/gophercloud/openstack/identity/v2/tokens"
opts := tokens.AuthOptions{ IdentityEndpoint: "{identityURL}", Username: "{username}", APIKey: "{apiKey}", }
token, err := tokens.Create(client, opts).Extract() {% endhighlight %}
A tenant is a container used to group or isolate API resources. Depending on the provider, a tenant can map to a customer, account, organization, or project.
### List tenants
{% highlight go %} import ( "github.com/rackspace/gophercloud/pagination" "github.com/rackspace/gophercloud/openstack/identity/v2/tenants" )
// We have the option of filtering the tenant list. If we want the full // collection, leave it as an empty struct opts := tenants.ListOpts{Limit: 10}
// Retrieve a pager (i.e. a paginated collection) pager := tenants.List(client, opts)
// Define an anonymous function to be executed on each page's iteration err := pager.EachPage(func(page pagination.Page) (bool, error) { tenantList, err := tenants.ExtractTenants(page)
for _, t := range tenantList { // "t" will be a tenants.Tenant } }) {% endhighlight %}