Contains experimental features for the GCS C++ Client Library.
Classes
AsyncClient
A client for Google Cloud Storage offering asynchronous operations.
AsyncConnection
The *Connection object for AsyncClient.
AsyncReader
A handle for streaming downloads.
AsyncReaderConnection
The *Connection object for AsyncReader.
AsyncRewriter
Perform object rewrites asynchronously.
AsyncRewriterConnection
An interface for asynchronous object rewrite implementations.
AsyncToken
Serialize streams of asynchronous operations.
AsyncWriter
Perform resumable uploads asynchronously.
AsyncWriterConnection
An interface to asynchronously perform resumable uploads.
BucketName
Represent bucket names.
IdempotencyPolicy
Define the interface for the AsyncClient's idempotency policy.
ReadPayload
A partial or full response to an asynchronous download.
ResumePolicy
Controls how the client library resumes uploads and downloads.
WritePayload
An opaque representation of the data for an object payload.
Structs
BufferedUploadHwmOption
Configure the flow control algorithm for buffered uploads.
BufferedUploadLwmOption
Configure the flow control algorithm for buffered uploads.
EnableCrc32cValidationOption
If enabled, the client computes (if necessary) and validates the CRC32C checksum of an object during uploads and downloads.
EnableGrpcMetricsOption
Enable gRPC telemetry for GCS RPCs.
EnableMD5ValidationOption
If enabled, the client computes (if necessary) and validates the MD5 hash of an object during uploads and downloads.
GrpcMetricsPeriodOption
gRPC telemetry export period.
GrpcPluginOption
Configure the GCS+gRPC plugin.
HttpVersionOption
Set the HTTP version used by the client.
IdempotencyPolicyOption
An option (see google::cloud::Options) to set the idempotency policy.
ResumePolicyOption
Configure the resume policy used in a request, client, or connection.
UseCrc32cValueOption
If this option is present, the client does not compute the MD5 hash of an object during uploads or downloads.
UseMD5ValueOption
If this option is present, the client does not compute the MD5 hash of an object during uploads or downloads.
Functions
MakeBucketName(absl::string_view)
Constructs a BucketName from the given full_name.
Returns a non-OK Status if full_name is improperly formed.
| Parameter | |
|---|---|
| Name | Description |
full_name |
|
| Returns | |
|---|---|
| Type | Description |
StatusOr< BucketName > |
|
MakeStrictIdempotencyPolicy()
Creates an idempotency policy where only safe operations are retried.
| Returns | |
|---|---|
| Type | Description |
std::unique_ptr< IdempotencyPolicy > |
|
MakeAlwaysRetryIdempotencyPolicy()
Creates an idempotency policy that retries all operations.
| Returns | |
|---|---|
| Type | Description |
std::unique_ptr< IdempotencyPolicy > |
|
ReadAll(AsyncReader, AsyncToken)
Accumulate all the responses from reader.
| Parameters | |
|---|---|
| Name | Description |
reader |
|
token |
|
| Returns | |
|---|---|
| Type | Description |
future< StatusOr< ReadPayload > > |
|
ReadAll(StatusOr< std::pair< AsyncReader, AsyncToken > >)
Accumulate all the responses in read or return the corresponding error.
| Parameter | |
|---|---|
| Name | Description |
read |
|
| Returns | |
|---|---|
| Type | Description |
future< StatusOr< ReadPayload > > |
|
ReadAll(future< StatusOr< std::pair< AsyncReader, AsyncToken > > >)
Wait until pending_read is satisfied and then accumulate all the responses, or return the corresponding error.
Example
namespace gcs_ex = google::cloud::storage_experimental;
auto coro =
[](gcs_ex::AsyncClient& client, std::string bucket_name,
std::string object_name) -> google::cloud::future<std::uint64_t> {
// For small objects, consider `ReadAll()` which accumulates all the
// contents in memory using background threads.
auto payload = (co_await gcs_ex::ReadAll(client.ReadObject(
gcs_ex::BucketName(std::move(bucket_name)),
std::move(object_name))))
.value();
std::uint64_t count = 0;
for (auto const& buffer : payload.contents()) {
count += std::count(buffer.begin(), buffer.end(), '\n');
}
co_return count;
};
| Parameter | |
|---|---|
| Name | Description |
pending_read |
|
| Returns | |
|---|---|
| Type | Description |
future< StatusOr< ReadPayload > > |
|
LimitedErrorCountResumePolicy(int)
Returns a factory which resumes up to maximum_resumes times.
| Parameter | |
|---|---|
| Name | Description |
maximum_resumes |
|
| Returns | |
|---|---|
| Type | Description |
ResumePolicyFactory |
|
StopOnConsecutiveErrorsResumePolicy()
Returns a factory which resumes as long as the previous attempt connected successfully.
| Returns | |
|---|---|
| Type | Description |
ResumePolicyFactory |
|
DefaultGrpcClient(Options)
Create a google::cloud::storage::Client object configured to use gRPC.
Example
void GrpcReadWrite(std::string const& bucket_name) {
namespace gcs = ::google::cloud::storage;
auto constexpr kText = R"""(Hello World!)""";
auto client = google::cloud::storage_experimental::DefaultGrpcClient();
auto object = client.InsertObject(bucket_name, "lorem.txt", kText);
if (!object) throw std::move(object).status();
auto input = client.ReadObject(bucket_name, "lorem.txt",
gcs::Generation(object->generation()));
std::string const actual(std::istreambuf_iterator<char>{input}, {});
if (input.bad()) throw google::cloud::Status(input.status());
std::cout << "The contents read back are:\n"
<< actual
<< "\nThe received checksums are: " << input.received_hash()
<< "\nThe computed checksums are: " << input.computed_hash()
<< "\nThe original hashes are: crc32c=" << object->crc32c()
<< ",md5=" << object->md5_hash() << "\n";
}
| Parameter | |
|---|---|
| Name | Description |
opts |
the configuration parameters for the Client. |
| Returns | |
|---|---|
| Type | Description |
google::cloud::storage::Client |
|
Type Aliases
ResumePolicyFactory
std::function< std::unique_ptr< ResumePolicy >()>
Creates new instances of a ResumePolicy.