Interface ServerContext

OptionalonCanceled

cancelSignal

• get cancelSignal(): AbortSignal

  An AbortSignal. The abort event is invoked when the method got canceled.

  Returns AbortSignal

deadline

• get deadline(): null | Date

  The deadline for the server call. Represents the time by which the server call must be completed. Returns null if no deadline is set.

  Returns null | Date

isCanceled

• get isCanceled(): boolean

  Returns whether this RPC failed before the server could provide its status to the client.

  Returns boolean

  true if the RPC was canceled, otherwise false.

  Remarks

  This may be due to an explicit API rejection from the client or server-side or due to the deadline being exceeded. It does NOT include errors due to a non-OK status return by the server application's request handler, including Status::CANCELED.

requestHeaders

• get requestHeaders(): Vrpc.Metadata

  The header key-value pairs sent from the client.

  Returns Vrpc.Metadata

  Remarks

  Note that keys may appear more than once. It is safe to use this method after headers has been received. Calls always start with the client sending headers so that access to this data is safe as soon as the call has started on the server side.

responseHeaders

• get responseHeaders(): Vrpc.Metadata

  The response headers associated with the server call.

  Returns Vrpc.Metadata

trailingHeaders

• get trailingHeaders(): Vrpc.Metadata

  The trailing headers associated with the server call.

  Returns Vrpc.Metadata

addResponseHeader

• addResponseHeader(key: string, value: string | Buffer<ArrayBufferLike>): void

  Adds a key-value pair to the headers associated with a server response call.

  Parameters

  • key: string

    The key for the header. If it is a binary value, it must end with "-bin". If it is an ASCII value, it must not end with "-bin".

  • value: string | Buffer<ArrayBufferLike>

    The value for the header, which can be a string or a Buffer.

  Returns void

  Remarks

  This method must only be called before sending response headers to the client. Which can happen explicitly, or implicitly when sending a response message or status to the client.

addTrailingHeader

• addTrailingHeader(key: string, value: string | Buffer<ArrayBufferLike>): void

  Adds a key-value pair to the trailing headers associated with a server call.

  Parameters

  • key: string

    The key for the headers.

  • value: string | Buffer<ArrayBufferLike>

    The value for the headers, which can be a string or a Buffer.

  Returns void

  Remarks

  This method must only be called before sending trailing headers to the client. Which happens when the call is finished and a status is sent to the client.

getDeadlineAsMsSinceEpoch

• getDeadlineAsMsSinceEpoch(): null | number

  Gets the deadline for the client call as a number representing ms since the epoch.

  Returns null | number

  The deadline as a Date object, or null if no deadline is set.

tryCancel

• tryCancel(): void

  Cancel the Call from the server.

  Returns void

  Remarks

  This is a best-effort API and depending on when it is called, the RPC may still appear successful to the client. For example, if tryCancel() is called on a separate thread, it might race with the server handler which might return success to the client before tryCancel() was even started by the thread.

  It is the caller's responsibility to prevent such races and ensure that if tryCancel() is called, the service implementation must return Status::CANCELED. The only exception is that if the service implementation is already returning an error status code, it is ok to not return Status::CANCELED even if tryCancel() was called.

  For reasons such as the above, it is generally preferred to explicitly finish an RPC by returning Status::CANCELED rather then using tryCancel.