diff options
Diffstat (limited to 'vendor/github.com/grpc-ecosystem/go-grpc-middleware/tags/context.go')
-rw-r--r-- | vendor/github.com/grpc-ecosystem/go-grpc-middleware/tags/context.go | 78 |
1 files changed, 78 insertions, 0 deletions
diff --git a/vendor/github.com/grpc-ecosystem/go-grpc-middleware/tags/context.go b/vendor/github.com/grpc-ecosystem/go-grpc-middleware/tags/context.go new file mode 100644 index 00000000..583025ce --- /dev/null +++ b/vendor/github.com/grpc-ecosystem/go-grpc-middleware/tags/context.go @@ -0,0 +1,78 @@ +package grpc_ctxtags + +import ( + "context" +) + +type ctxMarker struct{} + +var ( + // ctxMarkerKey is the Context value marker used by *all* logging middleware. + // The logging middleware object must interf + ctxMarkerKey = &ctxMarker{} + // NoopTags is a trivial, minimum overhead implementation of Tags for which all operations are no-ops. + NoopTags = &noopTags{} +) + +// Tags is the interface used for storing request tags between Context calls. +// The default implementation is *not* thread safe, and should be handled only in the context of the request. +type Tags interface { + // Set sets the given key in the metadata tags. + Set(key string, value interface{}) Tags + // Has checks if the given key exists. + Has(key string) bool + // Values returns a map of key to values. + // Do not modify the underlying map, please use Set instead. + Values() map[string]interface{} +} + +type mapTags struct { + values map[string]interface{} +} + +func (t *mapTags) Set(key string, value interface{}) Tags { + t.values[key] = value + return t +} + +func (t *mapTags) Has(key string) bool { + _, ok := t.values[key] + return ok +} + +func (t *mapTags) Values() map[string]interface{} { + return t.values +} + +type noopTags struct{} + +func (t *noopTags) Set(key string, value interface{}) Tags { + return t +} + +func (t *noopTags) Has(key string) bool { + return false +} + +func (t *noopTags) Values() map[string]interface{} { + return nil +} + +// Extracts returns a pre-existing Tags object in the Context. +// If the context wasn't set in a tag interceptor, a no-op Tag storage is returned that will *not* be propagated in context. +func Extract(ctx context.Context) Tags { + t, ok := ctx.Value(ctxMarkerKey).(Tags) + if !ok { + return NoopTags + } + + return t +} + +func setInContext(ctx context.Context, tags Tags) context.Context { + return context.WithValue(ctx, ctxMarkerKey, tags) +} + +func newTags() Tags { + return &mapTags{values: make(map[string]interface{})} +} |