providers/lib/client/user_agent.go

// Copyright (c) Facebook, Inc. and its affiliates.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package client

import (
	"fmt"
	"net/http"
)

// WithUserAgent wrapps the given client in a way that it always makes requests with User Agent header
func WithUserAgent(c Client, userAgent string) Client {
	return &userAgentClient{c, userAgent}
}

type userAgentClient struct {
	Client
	userAgent string
}

// Get is a part of the Client interface
func (c *userAgentClient) Get(url string) (*http.Response, error) {
	req, err := http.NewRequest("GET", url, nil)
	if err != nil {
		return nil, fmt.Errorf("cannot create http get request: %v", err)
	}

	// Do will set the user agent header
	return c.Do(req)
}

// Do is a part of the Client interface
func (c *userAgentClient) Do(req *http.Request) (*http.Response, error) {
	req.Header.Set("User-Agent", c.userAgent)
	return c.Client.Do(req)
}