diff options
Diffstat (limited to 'vendor/github.com/opentracing/opentracing-go/propagation.go')
| -rw-r--r-- | vendor/github.com/opentracing/opentracing-go/propagation.go | 176 |
1 files changed, 0 insertions, 176 deletions
diff --git a/vendor/github.com/opentracing/opentracing-go/propagation.go b/vendor/github.com/opentracing/opentracing-go/propagation.go deleted file mode 100644 index b0c275eb0..000000000 --- a/vendor/github.com/opentracing/opentracing-go/propagation.go +++ /dev/null @@ -1,176 +0,0 @@ -package opentracing - -import ( - "errors" - "net/http" -) - -/////////////////////////////////////////////////////////////////////////////// -// CORE PROPAGATION INTERFACES: -/////////////////////////////////////////////////////////////////////////////// - -var ( - // ErrUnsupportedFormat occurs when the `format` passed to Tracer.Inject() or - // Tracer.Extract() is not recognized by the Tracer implementation. - ErrUnsupportedFormat = errors.New("opentracing: Unknown or unsupported Inject/Extract format") - - // ErrSpanContextNotFound occurs when the `carrier` passed to - // Tracer.Extract() is valid and uncorrupted but has insufficient - // information to extract a SpanContext. - ErrSpanContextNotFound = errors.New("opentracing: SpanContext not found in Extract carrier") - - // ErrInvalidSpanContext errors occur when Tracer.Inject() is asked to - // operate on a SpanContext which it is not prepared to handle (for - // example, since it was created by a different tracer implementation). - ErrInvalidSpanContext = errors.New("opentracing: SpanContext type incompatible with tracer") - - // ErrInvalidCarrier errors occur when Tracer.Inject() or Tracer.Extract() - // implementations expect a different type of `carrier` than they are - // given. - ErrInvalidCarrier = errors.New("opentracing: Invalid Inject/Extract carrier") - - // ErrSpanContextCorrupted occurs when the `carrier` passed to - // Tracer.Extract() is of the expected type but is corrupted. - ErrSpanContextCorrupted = errors.New("opentracing: SpanContext data corrupted in Extract carrier") -) - -/////////////////////////////////////////////////////////////////////////////// -// BUILTIN PROPAGATION FORMATS: -/////////////////////////////////////////////////////////////////////////////// - -// BuiltinFormat is used to demarcate the values within package `opentracing` -// that are intended for use with the Tracer.Inject() and Tracer.Extract() -// methods. -type BuiltinFormat byte - -const ( - // Binary represents SpanContexts as opaque binary data. - // - // For Tracer.Inject(): the carrier must be an `io.Writer`. - // - // For Tracer.Extract(): the carrier must be an `io.Reader`. - Binary BuiltinFormat = iota - - // TextMap represents SpanContexts as key:value string pairs. - // - // Unlike HTTPHeaders, the TextMap format does not restrict the key or - // value character sets in any way. - // - // For Tracer.Inject(): the carrier must be a `TextMapWriter`. - // - // For Tracer.Extract(): the carrier must be a `TextMapReader`. - TextMap - - // HTTPHeaders represents SpanContexts as HTTP header string pairs. - // - // Unlike TextMap, the HTTPHeaders format requires that the keys and values - // be valid as HTTP headers as-is (i.e., character casing may be unstable - // and special characters are disallowed in keys, values should be - // URL-escaped, etc). - // - // For Tracer.Inject(): the carrier must be a `TextMapWriter`. - // - // For Tracer.Extract(): the carrier must be a `TextMapReader`. - // - // See HTTPHeadersCarrier for an implementation of both TextMapWriter - // and TextMapReader that defers to an http.Header instance for storage. - // For example, Inject(): - // - // carrier := opentracing.HTTPHeadersCarrier(httpReq.Header) - // err := span.Tracer().Inject( - // span.Context(), opentracing.HTTPHeaders, carrier) - // - // Or Extract(): - // - // carrier := opentracing.HTTPHeadersCarrier(httpReq.Header) - // clientContext, err := tracer.Extract( - // opentracing.HTTPHeaders, carrier) - // - HTTPHeaders -) - -// TextMapWriter is the Inject() carrier for the TextMap builtin format. With -// it, the caller can encode a SpanContext for propagation as entries in a map -// of unicode strings. -type TextMapWriter interface { - // Set a key:value pair to the carrier. Multiple calls to Set() for the - // same key leads to undefined behavior. - // - // NOTE: The backing store for the TextMapWriter may contain data unrelated - // to SpanContext. As such, Inject() and Extract() implementations that - // call the TextMapWriter and TextMapReader interfaces must agree on a - // prefix or other convention to distinguish their own key:value pairs. - Set(key, val string) -} - -// TextMapReader is the Extract() carrier for the TextMap builtin format. With it, -// the caller can decode a propagated SpanContext as entries in a map of -// unicode strings. -type TextMapReader interface { - // ForeachKey returns TextMap contents via repeated calls to the `handler` - // function. If any call to `handler` returns a non-nil error, ForeachKey - // terminates and returns that error. - // - // NOTE: The backing store for the TextMapReader may contain data unrelated - // to SpanContext. As such, Inject() and Extract() implementations that - // call the TextMapWriter and TextMapReader interfaces must agree on a - // prefix or other convention to distinguish their own key:value pairs. - // - // The "foreach" callback pattern reduces unnecessary copying in some cases - // and also allows implementations to hold locks while the map is read. - ForeachKey(handler func(key, val string) error) error -} - -// TextMapCarrier allows the use of regular map[string]string -// as both TextMapWriter and TextMapReader. -type TextMapCarrier map[string]string - -// ForeachKey conforms to the TextMapReader interface. -func (c TextMapCarrier) ForeachKey(handler func(key, val string) error) error { - for k, v := range c { - if err := handler(k, v); err != nil { - return err - } - } - return nil -} - -// Set implements Set() of opentracing.TextMapWriter -func (c TextMapCarrier) Set(key, val string) { - c[key] = val -} - -// HTTPHeadersCarrier satisfies both TextMapWriter and TextMapReader. -// -// Example usage for server side: -// -// carrier := opentracing.HTTPHeadersCarrier(httpReq.Header) -// clientContext, err := tracer.Extract(opentracing.HTTPHeaders, carrier) -// -// Example usage for client side: -// -// carrier := opentracing.HTTPHeadersCarrier(httpReq.Header) -// err := tracer.Inject( -// span.Context(), -// opentracing.HTTPHeaders, -// carrier) -// -type HTTPHeadersCarrier http.Header - -// Set conforms to the TextMapWriter interface. -func (c HTTPHeadersCarrier) Set(key, val string) { - h := http.Header(c) - h.Set(key, val) -} - -// ForeachKey conforms to the TextMapReader interface. -func (c HTTPHeadersCarrier) ForeachKey(handler func(key, val string) error) error { - for k, vals := range c { - for _, v := range vals { - if err := handler(k, v); err != nil { - return err - } - } - } - return nil -} |