claranet/wallix_bastion_exporter

package httpclient

import (
    "crypto/tls"
    "net/http"
    "net/http/cookiejar"
    "time"
)

// The configuration to build the HTTP client.
type HTTPConfig struct {
    Timeout       int
    Username      string
    Password      string
    Headers       map[string]string
    SkipVerify    bool
    CookieManager bool
}

// An http transport that injects basic auth into each request.
type TransportWithBasicAuth struct {
    http.RoundTripper
    Username string
    Password string
}

// Override the only method that the client actually calls on the transport to
// do the request.
func (t *TransportWithBasicAuth) RoundTrip(req *http.Request) (*http.Response, error) {
    req.SetBasicAuth(t.Username, t.Password)

    return t.RoundTripper.RoundTrip(req)
}

// Build returns a configured http.Client.
func (h *HTTPConfig) Build() (client *http.Client, err error) {
    roundTripper := func() http.RoundTripper {
        transport := http.DefaultTransport.(*http.Transport).Clone()

        transport.TLSClientConfig = &tls.Config{
            InsecureSkipVerify: h.SkipVerify, //nolint:gosec
        }

        return transport
    }()

    if h.Username != "" {
        roundTripper = &TransportWithBasicAuth{
            RoundTripper: roundTripper,
            Username:     h.Username,
            Password:     h.Password,
        }
    }

    if h.Headers == nil {
        h.Headers = map[string]string{}
    }

    roundTripper = &addHeader{
        rt:      roundTripper,
        headers: h.Headers,
    }

    client = &http.Client{
        Timeout:   time.Second * time.Duration(h.Timeout),
        Transport: roundTripper,
    }

    // Handle cookie authentication
    if h.CookieManager {
        cookieJar, err := cookiejar.New(nil)
        if err != nil {
            return nil, err
        }

        client.Jar = cookieJar
    }

    return client, nil
}

// Inject new haders into each request.
type addHeader struct {
    headers map[string]string
    rt      http.RoundTripper
}

// Allows to add header to each request done by this HTTP client.
func (h *addHeader) RoundTrip(req *http.Request) (*http.Response, error) {
    for k, v := range h.headers {
        req.Header.Add(k, v)
    }

    return h.rt.RoundTrip(req)
}