knative.dev/pkg@v0.0.0-20260602142205-ac97e43f6622/codegen/cmd/injection-gen/generators/client/client.go (about)

     1  /*
     2  Copyright 2019 The Knative Authors
     3  
     4  Licensed under the Apache License, Version 2.0 (the "License");
     5  you may not use this file except in compliance with the License.
     6  You may obtain a copy of the License at
     7  
     8      http://www.apache.org/licenses/LICENSE-2.0
     9  
    10  Unless required by applicable law or agreed to in writing, software
    11  distributed under the License is distributed on an "AS IS" BASIS,
    12  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  See the License for the specific language governing permissions and
    14  limitations under the License.
    15  */
    16  
    17  package client
    18  
    19  import (
    20  	"io"
    21  	"path/filepath"
    22  
    23  	"k8s.io/gengo/v2/generator"
    24  	"k8s.io/gengo/v2/namer"
    25  	"k8s.io/gengo/v2/types"
    26  	"k8s.io/klog/v2"
    27  	"knative.dev/pkg/codegen/cmd/injection-gen/args"
    28  )
    29  
    30  // New creates a new clientGenerator with the given args
    31  func New(args *args.Args) *clientGenerator {
    32  	return &clientGenerator{
    33  		GoGenerator: generator.GoGenerator{
    34  			OutputFilename: "client.go",
    35  		},
    36  		outputPackage:    filepath.Join(args.OutputPackagePath, "client"),
    37  		imports:          generator.NewImportTracker(),
    38  		clientSetPackage: args.VersionedClientSetPackage,
    39  	}
    40  }
    41  
    42  // clientGenerator produces a file of listers for a given GroupVersion and
    43  // type.
    44  type clientGenerator struct {
    45  	generator.GoGenerator
    46  
    47  	outputPackage    string
    48  	imports          namer.ImportTracker
    49  	clientSetPackage string
    50  	filtered         bool
    51  }
    52  
    53  func (g *clientGenerator) OutputPackagePath() string {
    54  	return g.outputPackage
    55  }
    56  
    57  var _ generator.Generator = (*clientGenerator)(nil)
    58  
    59  func (g *clientGenerator) Filter(c *generator.Context, t *types.Type) bool {
    60  	// We generate a single client, so return true once.
    61  	if !g.filtered {
    62  		g.filtered = true
    63  		return true
    64  	}
    65  	return false
    66  }
    67  
    68  func (g *clientGenerator) Namers(c *generator.Context) namer.NameSystems {
    69  	return namer.NameSystems{
    70  		"raw": namer.NewRawNamer(g.outputPackage, g.imports),
    71  	}
    72  }
    73  
    74  func (g *clientGenerator) Imports(c *generator.Context) (imports []string) {
    75  	imports = append(imports, g.imports.ImportLines()...)
    76  	return
    77  }
    78  
    79  func (g *clientGenerator) GenerateType(c *generator.Context, t *types.Type, w io.Writer) error {
    80  	sw := generator.NewSnippetWriter(w, c, "{{", "}}")
    81  
    82  	klog.V(5).Info("processing type ", t)
    83  
    84  	m := map[string]interface{}{
    85  		"clientSetNewForConfigOrDie": c.Universe.Function(types.Name{Package: g.clientSetPackage, Name: "NewForConfigOrDie"}),
    86  		"clientSetInterface":         c.Universe.Type(types.Name{Package: g.clientSetPackage, Name: "Interface"}),
    87  		"injectionRegisterClient":    c.Universe.Function(types.Name{Package: "knative.dev/pkg/injection", Name: "Default.RegisterClient"}),
    88  		"injectionRegisterClientFetcher": c.Universe.Function(types.Name{
    89  			Package: "knative.dev/pkg/injection",
    90  			Name:    "Default.RegisterClientFetcher",
    91  		}),
    92  		"restConfig": c.Universe.Type(types.Name{Package: "k8s.io/client-go/rest", Name: "Config"}),
    93  		"loggingFromContext": c.Universe.Function(types.Name{
    94  			Package: "knative.dev/pkg/logging",
    95  			Name:    "FromContext",
    96  		}),
    97  		"contextContext": c.Universe.Type(types.Name{
    98  			Package: "context",
    99  			Name:    "Context",
   100  		}),
   101  	}
   102  
   103  	sw.Do(injectionClient, m)
   104  
   105  	return sw.Error()
   106  }
   107  
   108  var injectionClient = `
   109  func init() {
   110  	{{.injectionRegisterClient|raw}}(withClientFromConfig)
   111  	{{.injectionRegisterClientFetcher|raw}}(func(ctx context.Context) interface{} {
   112  		return Get(ctx)
   113  	})
   114  }
   115  
   116  // Key is used as the key for associating information with a context.Context.
   117  type Key struct{}
   118  
   119  func withClientFromConfig(ctx {{.contextContext|raw}}, cfg *{{.restConfig|raw}}) context.Context {
   120  	return context.WithValue(ctx, Key{}, {{.clientSetNewForConfigOrDie|raw}}(cfg))
   121  }
   122  
   123  // Get extracts the {{.clientSetInterface|raw}} client from the context.
   124  func Get(ctx {{.contextContext|raw}}) {{.clientSetInterface|raw}} {
   125  	untyped := ctx.Value(Key{})
   126  	if untyped == nil {
   127  		if injection.GetConfig(ctx) == nil {
   128  		    {{.loggingFromContext|raw}}(ctx).Panic(
   129  		    	    "Unable to fetch {{.clientSetInterface}} from context. This context is not the application context (which is typically given to constructors via sharedmain).")
   130  		} else {
   131  		    {{.loggingFromContext|raw}}(ctx).Panic(
   132  		    	    "Unable to fetch {{.clientSetInterface}} from context.")
   133  		}
   134  	}
   135  	return untyped.({{.clientSetInterface|raw}})
   136  }
   137  `