/*
Package gophercloud provides a multi-vendor interface to OpenStack-compatible
clouds. The library has a three-level hierarchy: providers, services, and
resources.

Provider structs represent the service providers that offer and manage a
collection of services. Examples of providers include: OpenStack, Rackspace,
HP. These are defined like so:

  opts := gophercloud.AuthOptions{
    IdentityEndpoint: "https://my-openstack.com:5000/v2.0",
    Username: "{username}",
    Password: "{password}",
    TenantID: "{tenant_id}",
  }

  provider, err := openstack.AuthenticatedClient(opts)

Service structs are specific to a provider and handle all of the logic and
operations for a particular OpenStack service. Examples of services include:
Compute, Object Storage, Block Storage. In order to define one, you need to
pass in the parent provider, like so:

  opts := gophercloud.EndpointOpts{Region: "RegionOne"}

  client := openstack.NewComputeV2(provider, opts)

Resource structs are the domain models that services make use of in order
to work with and represent the state of API resources:

  server, err := servers.Get(client, "{serverId}").Extract()

Intermediate Result structs are returned for API operations, which allow
generic access to the HTTP headers, response body, and any errors associated
with the network transaction. To turn a result into a usable resource struct,
you must call the Extract method which is chained to the response, or an
Extract function from an applicable extension:

  result := servers.Get(client, "{serverId}")

  // Attempt to extract the disk configuration from the OS-DCF disk config
  // extension:
  config, err := diskconfig.ExtractGet(result)

All requests that enumerate a collection return a Pager struct that is used to
iterate through the results one page at a time. Use the EachPage method on that
Pager to handle each successive Page in a closure, then use the appropriate
extraction method from that request's package to interpret that Page as a slice
of results:

  err := servers.List(client, nil).EachPage(func (page pagination.Page) (bool, error) {
    s, err := servers.ExtractServers(page)
    if err != nil {
      return false, err
    }

    // Handle the []servers.Server slice.

    // Return "false" or an error to prematurely stop fetching new pages.
    return true, nil
  })

This top-level package contains utility functions and data types that are used
throughout the provider and service packages. Of particular note for end users
are the AuthOptions and EndpointOpts structs.
*/
package gophercloud