HTTP Client

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Mortar HTTP Client is no other than *http.Client.

Similar to gRPC Client Mortar makes http.Client very convenient to configure and adds Interceptors capabilities.

// HTTPClientBuilder is a builder interface to build http.Client with interceptors
type HTTPClientBuilder interface {
 AddInterceptors(...HTTPClientInterceptor) HTTPClientBuilder
 WithPreconfiguredClient(*http.Client) HTTPClientBuilder
 Build() *http.Client
}

// NewHTTPClientBuilder REST HTTP builder
//
// Useful when you want to create several *http.Client with different options
type NewHTTPClientBuilder func() HTTPClientBuilder

As you can see above, there is a builder and a function type alias NewHTTPClientBuilder. Using NewHTTPClientBuilder it’s possible to create different instances of http.Client which have a common set of Interceptors, but can be individually configured with additional ones. It’s very similar to what we have with gRPC.

// HTTPClientBuilder creates an injectable http.Client builder that can be predefined with Interceptors
//
// This function returns a closure that will always create a new builder. That way every usage can add different
// interceptors without influencing others
func HTTPClientBuilder(deps httpClientBuilderDeps) clientInt.NewHTTPClientBuilder {
 return func() clientInt.HTTPClientBuilder {
  return client.HTTPClientBuilder().AddInterceptors(deps.Interceptors...)
 }
}

The following code snippet is defined in Mortar. HTTPClientBuilder function is already in use if you register HttpClientFxOptions.

Now you know how it’s defined in Mortar, but how do you use it to create an http.Client ?

Example

For a complete working example look here.

import (
    "github.com/go-masonry/mortar/providers"
    "go.uber.org/fx"
)

func HttpClientFxOptions() fx.Option {
    return fx.Options(
        providers.HTTPClientBuildersFxOption(), // client builders for gRPC and HTTP
    )
}

Inject

import "github.com/go-masonry/mortar/interfaces/http/client"
...
type yourDeps struct {
    fx.In

    HTTPClientBuilder client.NewHTTPClientBuilder
}

Use

At this point it is possible to add additional Interceptors using deps.HTTPClientBuilder()... that will influence only this client instance.

// Create a client instance
var client *http.Client = deps.HTTPClientBuilder().Build()
var httpReq *http.Request = makeHTTPRequest()
 
response, err := w.client.Do(httpReq)

Interceptors