Thrift is a cross-language framework for cross-service communication. Developers write a language-independent definition of a service’s API (the “IDL”) and Thrift’s code generator makes server and client libraries for that API.


To add a Thrift client to your application, ensure that your service has’s Thrift build step integrated in its root

from baseplate.frameworks.thrift.command import ThriftBuildPyCommand



      "build_py": ThriftBuildPyCommand,

Then add the downstream service’s IDL to your application directory:

$ cp ~/src/other/other/other.thrift myservice/ will automatically run the Thrift compiler on this when building your application and put the output into a Python package within your application like yourservice.other_thrift. Import the client class and add it to your context object:

from .other_thrift import OtherService


def make_wsgi_app(app_config):

         "foo": ThriftClient(OtherService.Client),

then configure it in your application’s configuration file:



# required: the host:port to find the service at
foo.endpoint = localhost:9999

# optional: the size of the connection pool (default 10)
foo.size = 10

# optional: how long a connection can be alive before we
# recycle it (default 1 minute)
foo.max_age = 1 minute

# optional: how long before we time out when connecting
# or doing an RPC (default 1 second)
foo.timeout = 1 second

# optional: how many times we'll retry connecting (default 3)
foo.max_retries = 3


and finally use the attached client in request:

def my_method(request):


class baseplate.clients.thrift.ThriftClient(client_cls, **kwargs)[source]

Configure a Thrift client.

This is meant to be used with baseplate.Baseplate.configure_context().

See baseplate.lib.thrift_pool.thrift_pool_from_config() for available configuration settings.


client_cls (Any) – The class object of a Thrift-generated client class, e.g. YourService.Client.

class baseplate.clients.thrift.ThriftContextFactory(pool, client_cls)[source]

Thrift client pool context factory.

This factory will attach a proxy object with the same interface as your thrift client to an attribute on the RequestContext. When a thrift method is called on this proxy object, it will check out a connection from the connection pool and execute the RPC, automatically recording diagnostic information.

  • pool (ThriftConnectionPool) – The connection pool.

  • client_cls (Any) – The class object of a Thrift-generated client class, e.g. YourService.Client.

The proxy object has a retrying method which takes the same parameters as and acts as a context manager. The context manager returns another proxy object where Thrift service method calls will be automatically retried with the specified retry policy when transient errors occur:

with context.my_service.retrying(attempts=3) as svc:

Runtime Metrics

In addition to request-level metrics reported through spans, this wrapper reports connection pool statistics periodically via the Prometheus Exporter system. All metrics are tagged with client, the name given to configure_context() when registering this context factory.

The following metrics are reported:


The size limit for the connection pool.


How many connections have been established and are currently checked out and being used.

Changed in version 2.0: Runtime metrics were changed to use tags.