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docs snapshot for crossplane version `master`

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@ -12,50 +12,9 @@ concepts work together to allow for powerful separation of concern between
different personas in an organization, meaning that each member of a team
interacts with Crossplane at an appropriate level of abstraction.
![Crossplane Concepts]
The diagram above illustrates a common workflow using most of Crossplane's
functionality.
An infrastructure operator...
1. Installs Crossplane and one or more [providers] (in this case
[provider-azure]) as [packages]. This enables provisioning of external
infrastructure from the Kubernetes cluster.
2. Defines a new `CompositeMySQLInstance` composite resource and a corresponding
`MySQLInstance` resource claim by authoring a `CompositeResourceDefinition`.
3. Creates a `Composition` that instructs Crossplane how to render one or more
managed resources installed by providers in response to the creation of the
composite resource. In this case the `Composition` specifies that Azure
`MySQLServer` and `MySQLFirewallRule` [managed resources] should be created
to satisfy a `CompositeMySQLInstance`.
An application developer...
1. Creates an [OAM] `Component` for their service that specifies that they wish
to be run as an OAM `ContainerizedWorkload`.
2. Creates an OAM `Component` for their MySQL database that can be satisfied by
the `MySQLInstance` resource claim.
An application operator...
1. Creates an OAM `ApplicationConfiguration`, which is comprised of the two
`Component` types that were defined by the application developer, and a
`ManualScalerTrait` trait to modify the replicas in the
`ContainerizedWorkload`. In response, Crossplane translates the OAM types
into Kubernetes-native types, in this case a `Deployment` and `Service` for
the `ContainerizedWorkload` component, and a `MySQLServer` and
`MySQLFirewallRule` for the `MySQLInstance` component.
2. Crossplane provisions the external infrastructure and makes the connection
information available to the application, allowing it to connect to and
consume the MySQL database on Azure.
The concepts used in this workflow are explained in greater detail below and in
their individual documentation.
## Packages
Packages allow Crossplane to be extended to include new functionality. This
[Packages] allow Crossplane to be extended to include new functionality. This
typically looks like bundling a set of Kubernetes [CRDs] and [controllers] that
represent and manage external infrastructure (i.e. a provider), then installing
them into a cluster where Crossplane is running. Crossplane handles making sure
@ -90,12 +49,7 @@ learn more about all of these concepts in the [composition documentation].
<!-- Named Links -->
[Crossplane Concepts]: crossplane-concepts.png
[providers]: #providers
[provider-azure]: https://github.com/crossplane/provider-azure
[packages]: #packages
[managed resources]: #managed-resources
[OAM]: #oam
[Packages]: packages.md
[CRDs]: https://kubernetes.io/docs/concepts/extend-kubernetes/api-extension/custom-resources/
[controllers]: https://kubernetes.io/docs/concepts/extend-kubernetes/api-extension/custom-resources/#custom-controllers
[providers documentation]: providers.md