Documentation
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Overview ¶
Package roundtrip provides tooling for composing request/response behaviour through messages.
Index ¶
Constants ¶
This section is empty.
Variables ¶
var ErrNoStore = errors.New("result store not found within batch context")
ErrNoStore is an error returned by components attempting to write a message batch to a ResultStore but are unable to locate the store within the batch context.
Functions ¶
func AddResultStore ¶
func AddResultStore(msg types.Message, store ResultStore)
AddResultStore sets a result store within the context of the provided message that allows a roundtrip.Writer or any other component to propagate a resulting message back to the origin.
func SetAsResponse ¶
SetAsResponse takes a mutated message and stores it as a response message, this action fails if the message does not contain a valid ResultStore within its context.
Types ¶
type ResultStore ¶
type ResultStore interface {
// Add a message to the store. The message will be deep copied and have its
// context wiped before storing, and is therefore safe to add even when
// ownership of the message is about to be yielded.
Add(msg types.Message)
// Get the stored slice of messages.
Get() []types.Message
// Clear any currently stored messages.
Clear()
}
ResultStore is a type designed to be propagated along with a message as a way for an output destination to store the final version of the message payload as it saw it.
It is intended that this structure is placed within a message via an attached context, usually under the key 'result_store'.
func NewResultStore ¶
func NewResultStore() ResultStore
NewResultStore returns an implementation of ResultStore.
type ResultStoreKeyType ¶
type ResultStoreKeyType int
ResultStoreKeyType is the recommended type of a context key for adding ResultStores to a message context.
const ResultStoreKey ResultStoreKeyType = iota
ResultStoreKey is the recommended key value for adding ResultStores to a message context.
type Writer ¶
type Writer struct{}
Writer is a writer implementation that adds messages to a ResultStore located in the context of the first message part of each batch. This is essentially a mechanism that returns the result of a pipeline directly back to the origin of the message.
func (Writer) WaitForClose ¶
WaitForClose is a noop.
Source Files