github.com/gophercloud/gophercloud (go): 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 cloud providers that offer and manage a collection of services. You will generally want to create one Provider client per OpenStack cloud.  Use your OpenStack credentials to create a Provider client.  The IdentityEndpoint is typically refered to as "auth_url" or "OS_AUTH_URL" in information provided by the cloud operator. Additionally, the cloud may refer to TenantID or TenantName as project_id and project_name. Credentials are specified like so:  You can authenticate with a token by doing:  You may also use the openstack.AuthOptionsFromEnv() helper function. This function reads in standard environment variables frequently found in an OpenStack `openrc` file. Again note that Gophercloud currently uses "tenant" instead of "project".  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:  Resource structs are the domain models that services make use of in order to work with and represent the state of API resources:  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:  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:  If you want to obtain the entire collection of pages without doing any intermediary processing on each page, you can use the AllPages method:  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.  An example retry backoff function, which respects the 429 HTTP response code and a "Retry-After" header:
Keywords: go|openstack|sdk