github.com/florinpeter/operator-sdk@v0.8.2/pkg/restmapper/dynamicrestmapper.go (about)

     1  // Copyright 2019 The Operator-SDK Authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package restmapper
    16  
    17  import (
    18  	"k8s.io/apimachinery/pkg/api/meta"
    19  	"k8s.io/apimachinery/pkg/runtime/schema"
    20  	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
    21  	"k8s.io/client-go/discovery"
    22  	"k8s.io/client-go/rest"
    23  	"k8s.io/client-go/restmapper"
    24  )
    25  
    26  type DynamicRESTMapper struct {
    27  	client   discovery.DiscoveryInterface
    28  	delegate meta.RESTMapper
    29  }
    30  
    31  // NewDynamicRESTMapper returns a RESTMapper that dynamically discovers resource
    32  // types at runtime. This is in contrast to controller-manager's default RESTMapper, which
    33  // only checks resource types at startup, and so can't handle the case of first creating a
    34  // CRD and then creating an instance of that CRD.
    35  func NewDynamicRESTMapper(cfg *rest.Config) (meta.RESTMapper, error) {
    36  	client, err := discovery.NewDiscoveryClientForConfig(cfg)
    37  	if err != nil {
    38  		return nil, err
    39  	}
    40  
    41  	drm := &DynamicRESTMapper{client: client}
    42  	if err := drm.reload(); err != nil {
    43  		return nil, err
    44  	}
    45  	return drm, nil
    46  }
    47  
    48  func (drm *DynamicRESTMapper) reload() error {
    49  	gr, err := restmapper.GetAPIGroupResources(drm.client)
    50  	if err != nil {
    51  		return err
    52  	}
    53  	drm.delegate = restmapper.NewDiscoveryRESTMapper(gr)
    54  	return nil
    55  }
    56  
    57  // reloadOnError checks if an error indicates that the delegated RESTMapper needs to be
    58  // reloaded, and if so, reloads it and returns true.
    59  func (drm *DynamicRESTMapper) reloadOnError(err error) bool {
    60  	if _, matches := err.(*meta.NoKindMatchError); !matches {
    61  		return false
    62  	}
    63  	err = drm.reload()
    64  	if err != nil {
    65  		utilruntime.HandleError(err)
    66  	}
    67  	return err == nil
    68  }
    69  
    70  func (drm *DynamicRESTMapper) KindFor(resource schema.GroupVersionResource) (schema.GroupVersionKind, error) {
    71  	gvk, err := drm.delegate.KindFor(resource)
    72  	if drm.reloadOnError(err) {
    73  		gvk, err = drm.delegate.KindFor(resource)
    74  	}
    75  	return gvk, err
    76  }
    77  
    78  func (drm *DynamicRESTMapper) KindsFor(resource schema.GroupVersionResource) ([]schema.GroupVersionKind, error) {
    79  	gvks, err := drm.delegate.KindsFor(resource)
    80  	if drm.reloadOnError(err) {
    81  		gvks, err = drm.delegate.KindsFor(resource)
    82  	}
    83  	return gvks, err
    84  }
    85  
    86  func (drm *DynamicRESTMapper) ResourceFor(input schema.GroupVersionResource) (schema.GroupVersionResource, error) {
    87  	gvr, err := drm.delegate.ResourceFor(input)
    88  	if drm.reloadOnError(err) {
    89  		gvr, err = drm.delegate.ResourceFor(input)
    90  	}
    91  	return gvr, err
    92  }
    93  
    94  func (drm *DynamicRESTMapper) ResourcesFor(input schema.GroupVersionResource) ([]schema.GroupVersionResource, error) {
    95  	gvrs, err := drm.delegate.ResourcesFor(input)
    96  	if drm.reloadOnError(err) {
    97  		gvrs, err = drm.delegate.ResourcesFor(input)
    98  	}
    99  	return gvrs, err
   100  }
   101  
   102  func (drm *DynamicRESTMapper) RESTMapping(gk schema.GroupKind, versions ...string) (*meta.RESTMapping, error) {
   103  	m, err := drm.delegate.RESTMapping(gk, versions...)
   104  	if drm.reloadOnError(err) {
   105  		m, err = drm.delegate.RESTMapping(gk, versions...)
   106  	}
   107  	return m, err
   108  }
   109  
   110  func (drm *DynamicRESTMapper) RESTMappings(gk schema.GroupKind, versions ...string) ([]*meta.RESTMapping, error) {
   111  	ms, err := drm.delegate.RESTMappings(gk, versions...)
   112  	if drm.reloadOnError(err) {
   113  		ms, err = drm.delegate.RESTMappings(gk, versions...)
   114  	}
   115  	return ms, err
   116  }
   117  
   118  func (drm *DynamicRESTMapper) ResourceSingularizer(resource string) (singular string, err error) {
   119  	s, err := drm.delegate.ResourceSingularizer(resource)
   120  	if drm.reloadOnError(err) {
   121  		s, err = drm.delegate.ResourceSingularizer(resource)
   122  	}
   123  	return s, err
   124  }