google::cloud::GenericPollingPolicy< Retry, Backoff > Class Template Reference

Construct a polling policy from existing Retry and Backoff policies. More...

#include <google/cloud/polling_policy.h>

Public Member Functions
	GenericPollingPolicy (Retry retry_policy, Backoff backoff_policy)
std::unique_ptr< PollingPolicy >	clone () const override
	Return a copy of the current policy. More...
bool	OnFailure (Status const &status) override
	A callback to indicate that a polling attempt failed. More...
std::chrono::milliseconds	WaitPeriod () override
	How long should the polling loop wait before trying again. More...

Detailed Description

template<typename Retry, typename Backoff>
class google::cloud::GenericPollingPolicy< Retry, Backoff >

Construct a polling policy from existing Retry and Backoff policies.

A polling policy can be built by composing a retry and backoff policy. For example, to create a polling policy that "retries N times, waiting a fixed period between retries" you could compose the "try N times" retry policy with the "wait a fixed period between retries" backoff policy.

This class makes it easier to create such composed polling policies.

Template Parameters

Retry	the retry policy used to limit the number of errors or the total duration of the polling loop.
Backoff	the backoff policy used to control how often the library polls.

Constructor & Destructor Documentation

GenericPollingPolicy()

template<typename Retry , typename Backoff >

google::cloud::GenericPollingPolicy< Retry, Backoff >::GenericPollingPolicy ( Retry  retry_policy, Backoff  backoff_policy  )

inline

Member Function Documentation

clone()

template<typename Retry , typename Backoff >

std::unique_ptr< PollingPolicy > google::cloud::GenericPollingPolicy< Retry, Backoff >::clone ( ) const

inlineoverridevirtual

Return a copy of the current policy.

This function is called at the beginning of the polling loop. Policies that are based on relative time should restart their timers when this function is called.

Implements google::cloud::PollingPolicy.

OnFailure()

template<typename Retry , typename Backoff >

bool google::cloud::GenericPollingPolicy< Retry, Backoff >::OnFailure ( Status const &  status )

inlineoverridevirtual

A callback to indicate that a polling attempt failed.

This is called when a polling request fails. Note that this callback is not invoked when the polling request succeeds with "operation not done".

Returns

true if the failure should be treated as transient and the polling loop should continue.

Implements google::cloud::PollingPolicy.

WaitPeriod()

template<typename Retry , typename Backoff >

std::chrono::milliseconds google::cloud::GenericPollingPolicy< Retry, Backoff >::WaitPeriod ( )

inlineoverridevirtual

How long should the polling loop wait before trying again.

Implements google::cloud::PollingPolicy.