Package list golang-github-go-kit-kit / 8b79fcc
examples/addsvc: README and other documentation Peter Bourgon 4 years ago
4 changed file(s) with 23 addition(s) and 3 deletion(s). Raw diff Collapse all Expand all
0 # addsvc
1
2 addsvc is an example microservice which takes full advantage of most of Go
3 kit's features, including both service- and transport-level middlewares,
4 speaking multiple transports simultaneously, distributed tracing, and rich
5 error definitions. The server binary is available in cmd/addsvc. The client
6 binary is available in cmd/addcli.
7
8 Finally, the addtransport package provides both server and clients for each
9 supported transport. The client structs bake-in certain middlewares, in order to
10 demonstrate the _client library pattern_. But beware: client libraries are
11 generally a bad idea, because they easily lead to the
12 [distributed monolith antipattern](https://www.microservices.com/talks/dont-build-a-distributed-monolith/).
13 If you don't _know_ you need to use one in your organization, it's probably best
14 avoided: prefer moving that logic to consumers, and relying on
15 [contract testing](https://docs.pact.io/best_practices/contract_tests_not_functional_tests.html)
16 to detect incompatibilities.
6767
6868 // NewGRPCClient returns an AddService backed by a gRPC server at the other end
6969 // of the conn. The caller is responsible for constructing the conn, and
70 // eventually closing the underlying transport.
70 // eventually closing the underlying transport. We bake-in certain middlewares,
71 // implementing the client library pattern.
7172 func NewGRPCClient(conn *grpc.ClientConn, tracer stdopentracing.Tracer, logger log.Logger) addservice.Service {
7273 // We construct a single ratelimiter middleware, to limit the total outgoing
7374 // QPS from this client to all methods on the remote instance. We also
5050
5151 // NewHTTPClient returns an AddService backed by an HTTP server living at the
5252 // remote instance. We expect instance to come from a service discovery system,
53 // so likely of the form "host:port".
53 // so likely of the form "host:port". We bake-in certain middlewares,
54 // implementing the client library pattern.
5455 func NewHTTPClient(instance string, tracer stdopentracing.Tracer, logger log.Logger) (addservice.Service, error) {
5556 // Quickly sanitize the instance string.
5657 if !strings.HasPrefix(instance, "http") {
5050
5151 // NewThriftClient returns an AddService backed by a Thrift server described by
5252 // the provided client. The caller is responsible for constructing the client,
53 // and eventually closing the underlying transport.
53 // and eventually closing the underlying transport. We bake-in certain middlewares,
54 // implementing the client library pattern.
5455 func NewThriftClient(client *addthrift.AddServiceClient) addservice.Service {
5556 // We construct a single ratelimiter middleware, to limit the total outgoing
5657 // QPS from this client to all methods on the remote instance. We also