vendor/github.com/prometheus/common/config/http_config.go - cloudstack-kubernetes-provider - Git at Google

 // Copyright 2016 The Prometheus Authors
 // 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 config

 import (
 	"crypto/tls"
 	"crypto/x509"
 	"fmt"
 	"io/ioutil"
 	"net/http"
 	"net/url"
 	"strings"
 	"time"

 	"github.com/mwitkow/go-conntrack"
 	"gopkg.in/yaml.v2"
 )

 // BasicAuth contains basic HTTP authentication credentials.
 type BasicAuth struct {
 	Username     string `yaml:"username"`
 	Password     Secret `yaml:"password,omitempty"`
 	PasswordFile string `yaml:"password_file,omitempty"`
 }

 // URL is a custom URL type that allows validation at configuration load time.
 type URL struct {
 	*url.URL
 }

 // UnmarshalYAML implements the yaml.Unmarshaler interface for URLs.
 func (u *URL) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	var s string
 	if err := unmarshal(&s); err != nil {
 		return err
 	}

 	urlp, err := url.Parse(s)
 	if err != nil {
 		return err
 	}
 	u.URL = urlp
 	return nil
 }

 // MarshalYAML implements the yaml.Marshaler interface for URLs.
 func (u URL) MarshalYAML() (interface{}, error) {
 	if u.URL != nil {
 		return u.String(), nil
 	}
 	return nil, nil
 }

 // HTTPClientConfig configures an HTTP client.
 type HTTPClientConfig struct {
 	// The HTTP basic authentication credentials for the targets.
 	BasicAuth *BasicAuth `yaml:"basic_auth,omitempty"`
 	// The bearer token for the targets.
 	BearerToken Secret `yaml:"bearer_token,omitempty"`
 	// The bearer token file for the targets.
 	BearerTokenFile string `yaml:"bearer_token_file,omitempty"`
 	// HTTP proxy server to use to connect to the targets.
 	ProxyURL URL `yaml:"proxy_url,omitempty"`
 	// TLSConfig to use to connect to the targets.
 	TLSConfig TLSConfig `yaml:"tls_config,omitempty"`
 }

 // Validate validates the HTTPClientConfig to check only one of BearerToken,
 // BasicAuth and BearerTokenFile is configured.
 func (c *HTTPClientConfig) Validate() error {
 	if len(c.BearerToken) > 0 && len(c.BearerTokenFile) > 0 {
 		return fmt.Errorf("at most one of bearer_token & bearer_token_file must be configured")
 	}
 	if c.BasicAuth != nil && (len(c.BearerToken) > 0 || len(c.BearerTokenFile) > 0) {
 		return fmt.Errorf("at most one of basic_auth, bearer_token & bearer_token_file must be configured")
 	}
 	if c.BasicAuth != nil && (string(c.BasicAuth.Password) != "" && c.BasicAuth.PasswordFile != "") {
 		return fmt.Errorf("at most one of basic_auth password & password_file must be configured")
 	}
 	return nil
 }

 // UnmarshalYAML implements the yaml.Unmarshaler interface
 func (c *HTTPClientConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	type plain HTTPClientConfig
 	if err := unmarshal((*plain)(c)); err != nil {
 		return err
 	}
 	return c.Validate()
 }

 // UnmarshalYAML implements the yaml.Unmarshaler interface.
 func (a *BasicAuth) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	type plain BasicAuth
 	return unmarshal((*plain)(a))
 }

 // NewClient returns a http.Client using the specified http.RoundTripper.
 func newClient(rt http.RoundTripper) *http.Client {
 	return &http.Client{Transport: rt}
 }

 // NewClientFromConfig returns a new HTTP client configured for the
 // given config.HTTPClientConfig. The name is used as go-conntrack metric label.
 func NewClientFromConfig(cfg HTTPClientConfig, name string) (*http.Client, error) {
 	rt, err := NewRoundTripperFromConfig(cfg, name)
 	if err != nil {
 		return nil, err
 	}
 	return newClient(rt), nil
 }

 // NewRoundTripperFromConfig returns a new HTTP RoundTripper configured for the
 // given config.HTTPClientConfig. The name is used as go-conntrack metric label.
 func NewRoundTripperFromConfig(cfg HTTPClientConfig, name string) (http.RoundTripper, error) {
 	tlsConfig, err := NewTLSConfig(&cfg.TLSConfig)
 	if err != nil {
 		return nil, err
 	}
 	// The only timeout we care about is the configured scrape timeout.
 	// It is applied on request. So we leave out any timings here.
 	var rt http.RoundTripper = &http.Transport{
 		Proxy:               http.ProxyURL(cfg.ProxyURL.URL),
 		MaxIdleConns:        20000,
 		MaxIdleConnsPerHost: 1000, // see https://github.com/golang/go/issues/13801
 		DisableKeepAlives:   false,
 		TLSClientConfig:     tlsConfig,
 		DisableCompression:  true,
 		// 5 minutes is typically above the maximum sane scrape interval. So we can
 		// use keepalive for all configurations.
 		IdleConnTimeout: 5 * time.Minute,
 		DialContext: conntrack.NewDialContextFunc(
 			conntrack.DialWithTracing(),
 			conntrack.DialWithName(name),
 		),
 	}

 	// If a bearer token is provided, create a round tripper that will set the
 	// Authorization header correctly on each request.
 	if len(cfg.BearerToken) > 0 {
 		rt = NewBearerAuthRoundTripper(cfg.BearerToken, rt)
 	} else if len(cfg.BearerTokenFile) > 0 {
 		rt = NewBearerAuthFileRoundTripper(cfg.BearerTokenFile, rt)
 	}

 	if cfg.BasicAuth != nil {
 		rt = NewBasicAuthRoundTripper(cfg.BasicAuth.Username, cfg.BasicAuth.Password, cfg.BasicAuth.PasswordFile, rt)
 	}

 	// Return a new configured RoundTripper.
 	return rt, nil
 }

 type bearerAuthRoundTripper struct {
 	bearerToken Secret
 	rt          http.RoundTripper
 }

 // NewBearerAuthRoundTripper adds the provided bearer token to a request unless the authorization
 // header has already been set.
 func NewBearerAuthRoundTripper(token Secret, rt http.RoundTripper) http.RoundTripper {
 	return &bearerAuthRoundTripper{token, rt}
 }

 func (rt *bearerAuthRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 	if len(req.Header.Get("Authorization")) == 0 {
 		req = cloneRequest(req)
 		req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", string(rt.bearerToken)))
 	}
 	return rt.rt.RoundTrip(req)
 }

 type bearerAuthFileRoundTripper struct {
 	bearerFile string
 	rt         http.RoundTripper
 }

 // NewBearerAuthFileRoundTripper adds the bearer token read from the provided file to a request unless
 // the authorization header has already been set. This file is read for every request.
 func NewBearerAuthFileRoundTripper(bearerFile string, rt http.RoundTripper) http.RoundTripper {
 	return &bearerAuthFileRoundTripper{bearerFile, rt}
 }

 func (rt *bearerAuthFileRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 	if len(req.Header.Get("Authorization")) == 0 {
 		b, err := ioutil.ReadFile(rt.bearerFile)
 		if err != nil {
 			return nil, fmt.Errorf("unable to read bearer token file %s: %s", rt.bearerFile, err)
 		}
 		bearerToken := strings.TrimSpace(string(b))

 		req = cloneRequest(req)
 		req.Header.Set("Authorization", "Bearer "+bearerToken)
 	}

 	return rt.rt.RoundTrip(req)
 }

 type basicAuthRoundTripper struct {
 	username     string
 	password     Secret
 	passwordFile string
 	rt           http.RoundTripper
 }

 // NewBasicAuthRoundTripper will apply a BASIC auth authorization header to a request unless it has
 // already been set.
 func NewBasicAuthRoundTripper(username string, password Secret, passwordFile string, rt http.RoundTripper) http.RoundTripper {
 	return &basicAuthRoundTripper{username, password, passwordFile, rt}
 }

 func (rt *basicAuthRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
 	if len(req.Header.Get("Authorization")) != 0 {
 		return rt.rt.RoundTrip(req)
 	}
 	req = cloneRequest(req)
 	if rt.passwordFile != "" {
 		bs, err := ioutil.ReadFile(rt.passwordFile)
 		if err != nil {
 			return nil, fmt.Errorf("unable to read basic auth password file %s: %s", rt.passwordFile, err)
 		}
 		req.SetBasicAuth(rt.username, strings.TrimSpace(string(bs)))
 	} else {
 		req.SetBasicAuth(rt.username, strings.TrimSpace(string(rt.password)))
 	}
 	return rt.rt.RoundTrip(req)
 }

 // cloneRequest returns a clone of the provided *http.Request.
 // The clone is a shallow copy of the struct and its Header map.
 func cloneRequest(r *http.Request) *http.Request {
 	// Shallow copy of the struct.
 	r2 := new(http.Request)
 	*r2 = *r
 	// Deep copy of the Header.
 	r2.Header = make(http.Header)
 	for k, s := range r.Header {
 		r2.Header[k] = s
 	}
 	return r2
 }

 // NewTLSConfig creates a new tls.Config from the given TLSConfig.
 func NewTLSConfig(cfg *TLSConfig) (*tls.Config, error) {
 	tlsConfig := &tls.Config{InsecureSkipVerify: cfg.InsecureSkipVerify}

 	// If a CA cert is provided then let's read it in so we can validate the
 	// scrape target's certificate properly.
 	if len(cfg.CAFile) > 0 {
 		caCertPool := x509.NewCertPool()
 		// Load CA cert.
 		caCert, err := ioutil.ReadFile(cfg.CAFile)
 		if err != nil {
 			return nil, fmt.Errorf("unable to use specified CA cert %s: %s", cfg.CAFile, err)
 		}
 		caCertPool.AppendCertsFromPEM(caCert)
 		tlsConfig.RootCAs = caCertPool
 	}

 	if len(cfg.ServerName) > 0 {
 		tlsConfig.ServerName = cfg.ServerName
 	}
 	// If a client cert & key is provided then configure TLS config accordingly.
 	if len(cfg.CertFile) > 0 && len(cfg.KeyFile) == 0 {
 		return nil, fmt.Errorf("client cert file %q specified without client key file", cfg.CertFile)
 	} else if len(cfg.KeyFile) > 0 && len(cfg.CertFile) == 0 {
 		return nil, fmt.Errorf("client key file %q specified without client cert file", cfg.KeyFile)
 	} else if len(cfg.CertFile) > 0 && len(cfg.KeyFile) > 0 {
 		cert, err := tls.LoadX509KeyPair(cfg.CertFile, cfg.KeyFile)
 		if err != nil {
 			return nil, fmt.Errorf("unable to use specified client cert (%s) & key (%s): %s", cfg.CertFile, cfg.KeyFile, err)
 		}
 		tlsConfig.Certificates = []tls.Certificate{cert}
 	}
 	tlsConfig.BuildNameToCertificate()

 	return tlsConfig, nil
 }

 // TLSConfig configures the options for TLS connections.
 type TLSConfig struct {
 	// The CA cert to use for the targets.
 	CAFile string `yaml:"ca_file,omitempty"`
 	// The client cert file for the targets.
 	CertFile string `yaml:"cert_file,omitempty"`
 	// The client key file for the targets.
 	KeyFile string `yaml:"key_file,omitempty"`
 	// Used to verify the hostname for the targets.
 	ServerName string `yaml:"server_name,omitempty"`
 	// Disable target certificate validation.
 	InsecureSkipVerify bool `yaml:"insecure_skip_verify"`
 }

 // UnmarshalYAML implements the yaml.Unmarshaler interface.
 func (c *TLSConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
 	type plain TLSConfig
 	return unmarshal((*plain)(c))
 }

 func (c HTTPClientConfig) String() string {
 	b, err := yaml.Marshal(c)
 	if err != nil {
 		return fmt.Sprintf("<error creating http client config string: %s>", err)
 	}
 	return string(b)
 }
	// Copyright 2016 The Prometheus Authors
	// 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 config

	import (
	"crypto/tls"
	"crypto/x509"
	"fmt"
	"io/ioutil"
	"net/http"
	"net/url"
	"strings"
	"time"

	"github.com/mwitkow/go-conntrack"
	"gopkg.in/yaml.v2"
	)

	// BasicAuth contains basic HTTP authentication credentials.
	type BasicAuth struct {
	Username string `yaml:"username"`
	Password Secret `yaml:"password,omitempty"`
	PasswordFile string `yaml:"password_file,omitempty"`
	}

	// URL is a custom URL type that allows validation at configuration load time.
	type URL struct {
	*url.URL
	}

	// UnmarshalYAML implements the yaml.Unmarshaler interface for URLs.
	func (u *URL) UnmarshalYAML(unmarshal func(interface{}) error) error {
	var s string
	if err := unmarshal(&s); err != nil {
	return err
	}

	urlp, err := url.Parse(s)
	if err != nil {
	return err
	}
	u.URL = urlp
	return nil
	}

	// MarshalYAML implements the yaml.Marshaler interface for URLs.
	func (u URL) MarshalYAML() (interface{}, error) {
	if u.URL != nil {
	return u.String(), nil
	}
	return nil, nil
	}

	// HTTPClientConfig configures an HTTP client.
	type HTTPClientConfig struct {
	// The HTTP basic authentication credentials for the targets.
	BasicAuth *BasicAuth `yaml:"basic_auth,omitempty"`
	// The bearer token for the targets.
	BearerToken Secret `yaml:"bearer_token,omitempty"`
	// The bearer token file for the targets.
	BearerTokenFile string `yaml:"bearer_token_file,omitempty"`
	// HTTP proxy server to use to connect to the targets.
	ProxyURL URL `yaml:"proxy_url,omitempty"`
	// TLSConfig to use to connect to the targets.
	TLSConfig TLSConfig `yaml:"tls_config,omitempty"`
	}

	// Validate validates the HTTPClientConfig to check only one of BearerToken,
	// BasicAuth and BearerTokenFile is configured.
	func (c *HTTPClientConfig) Validate() error {
	if len(c.BearerToken) > 0 && len(c.BearerTokenFile) > 0 {
	return fmt.Errorf("at most one of bearer_token & bearer_token_file must be configured")
	}
	if c.BasicAuth != nil && (len(c.BearerToken) > 0 \|\| len(c.BearerTokenFile) > 0) {
	return fmt.Errorf("at most one of basic_auth, bearer_token & bearer_token_file must be configured")
	}
	if c.BasicAuth != nil && (string(c.BasicAuth.Password) != "" && c.BasicAuth.PasswordFile != "") {
	return fmt.Errorf("at most one of basic_auth password & password_file must be configured")
	}
	return nil
	}

	// UnmarshalYAML implements the yaml.Unmarshaler interface
	func (c *HTTPClientConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
	type plain HTTPClientConfig
	if err := unmarshal((*plain)(c)); err != nil {
	return err
	}
	return c.Validate()
	}

	// UnmarshalYAML implements the yaml.Unmarshaler interface.
	func (a *BasicAuth) UnmarshalYAML(unmarshal func(interface{}) error) error {
	type plain BasicAuth
	return unmarshal((*plain)(a))
	}

	// NewClient returns a http.Client using the specified http.RoundTripper.
	func newClient(rt http.RoundTripper) *http.Client {
	return &http.Client{Transport: rt}
	}

	// NewClientFromConfig returns a new HTTP client configured for the
	// given config.HTTPClientConfig. The name is used as go-conntrack metric label.
	func NewClientFromConfig(cfg HTTPClientConfig, name string) (*http.Client, error) {
	rt, err := NewRoundTripperFromConfig(cfg, name)
	if err != nil {
	return nil, err
	}
	return newClient(rt), nil
	}

	// NewRoundTripperFromConfig returns a new HTTP RoundTripper configured for the
	// given config.HTTPClientConfig. The name is used as go-conntrack metric label.
	func NewRoundTripperFromConfig(cfg HTTPClientConfig, name string) (http.RoundTripper, error) {
	tlsConfig, err := NewTLSConfig(&cfg.TLSConfig)
	if err != nil {
	return nil, err
	}
	// The only timeout we care about is the configured scrape timeout.
	// It is applied on request. So we leave out any timings here.
	var rt http.RoundTripper = &http.Transport{
	Proxy: http.ProxyURL(cfg.ProxyURL.URL),
	MaxIdleConns: 20000,
	MaxIdleConnsPerHost: 1000, // see https://github.com/golang/go/issues/13801
	DisableKeepAlives: false,
	TLSClientConfig: tlsConfig,
	DisableCompression: true,
	// 5 minutes is typically above the maximum sane scrape interval. So we can
	// use keepalive for all configurations.
	IdleConnTimeout: 5 * time.Minute,
	DialContext: conntrack.NewDialContextFunc(
	conntrack.DialWithTracing(),
	conntrack.DialWithName(name),
	),
	}

	// If a bearer token is provided, create a round tripper that will set the
	// Authorization header correctly on each request.
	if len(cfg.BearerToken) > 0 {
	rt = NewBearerAuthRoundTripper(cfg.BearerToken, rt)
	} else if len(cfg.BearerTokenFile) > 0 {
	rt = NewBearerAuthFileRoundTripper(cfg.BearerTokenFile, rt)
	}

	if cfg.BasicAuth != nil {
	rt = NewBasicAuthRoundTripper(cfg.BasicAuth.Username, cfg.BasicAuth.Password, cfg.BasicAuth.PasswordFile, rt)
	}

	// Return a new configured RoundTripper.
	return rt, nil
	}

	type bearerAuthRoundTripper struct {
	bearerToken Secret
	rt http.RoundTripper
	}

	// NewBearerAuthRoundTripper adds the provided bearer token to a request unless the authorization
	// header has already been set.
	func NewBearerAuthRoundTripper(token Secret, rt http.RoundTripper) http.RoundTripper {
	return &bearerAuthRoundTripper{token, rt}
	}

	func (rt bearerAuthRoundTripper) RoundTrip(req http.Request) (*http.Response, error) {
	if len(req.Header.Get("Authorization")) == 0 {
	req = cloneRequest(req)
	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", string(rt.bearerToken)))
	}
	return rt.rt.RoundTrip(req)
	}

	type bearerAuthFileRoundTripper struct {
	bearerFile string
	rt http.RoundTripper
	}

	// NewBearerAuthFileRoundTripper adds the bearer token read from the provided file to a request unless
	// the authorization header has already been set. This file is read for every request.
	func NewBearerAuthFileRoundTripper(bearerFile string, rt http.RoundTripper) http.RoundTripper {
	return &bearerAuthFileRoundTripper{bearerFile, rt}
	}

	func (rt bearerAuthFileRoundTripper) RoundTrip(req http.Request) (*http.Response, error) {
	if len(req.Header.Get("Authorization")) == 0 {
	b, err := ioutil.ReadFile(rt.bearerFile)
	if err != nil {
	return nil, fmt.Errorf("unable to read bearer token file %s: %s", rt.bearerFile, err)
	}
	bearerToken := strings.TrimSpace(string(b))

	req = cloneRequest(req)
	req.Header.Set("Authorization", "Bearer "+bearerToken)
	}

	return rt.rt.RoundTrip(req)
	}

	type basicAuthRoundTripper struct {
	username string
	password Secret
	passwordFile string
	rt http.RoundTripper
	}

	// NewBasicAuthRoundTripper will apply a BASIC auth authorization header to a request unless it has
	// already been set.
	func NewBasicAuthRoundTripper(username string, password Secret, passwordFile string, rt http.RoundTripper) http.RoundTripper {
	return &basicAuthRoundTripper{username, password, passwordFile, rt}
	}

	func (rt basicAuthRoundTripper) RoundTrip(req http.Request) (*http.Response, error) {
	if len(req.Header.Get("Authorization")) != 0 {
	return rt.rt.RoundTrip(req)
	}
	req = cloneRequest(req)
	if rt.passwordFile != "" {
	bs, err := ioutil.ReadFile(rt.passwordFile)
	if err != nil {
	return nil, fmt.Errorf("unable to read basic auth password file %s: %s", rt.passwordFile, err)
	}
	req.SetBasicAuth(rt.username, strings.TrimSpace(string(bs)))
	} else {
	req.SetBasicAuth(rt.username, strings.TrimSpace(string(rt.password)))
	}
	return rt.rt.RoundTrip(req)
	}

	// cloneRequest returns a clone of the provided *http.Request.
	// The clone is a shallow copy of the struct and its Header map.
	func cloneRequest(r http.Request) http.Request {
	// Shallow copy of the struct.
	r2 := new(http.Request)
	r2 = r
	// Deep copy of the Header.
	r2.Header = make(http.Header)
	for k, s := range r.Header {
	r2.Header[k] = s
	}
	return r2
	}

	// NewTLSConfig creates a new tls.Config from the given TLSConfig.
	func NewTLSConfig(cfg TLSConfig) (tls.Config, error) {
	tlsConfig := &tls.Config{InsecureSkipVerify: cfg.InsecureSkipVerify}

	// If a CA cert is provided then let's read it in so we can validate the
	// scrape target's certificate properly.
	if len(cfg.CAFile) > 0 {
	caCertPool := x509.NewCertPool()
	// Load CA cert.
	caCert, err := ioutil.ReadFile(cfg.CAFile)
	if err != nil {
	return nil, fmt.Errorf("unable to use specified CA cert %s: %s", cfg.CAFile, err)
	}
	caCertPool.AppendCertsFromPEM(caCert)
	tlsConfig.RootCAs = caCertPool
	}

	if len(cfg.ServerName) > 0 {
	tlsConfig.ServerName = cfg.ServerName
	}
	// If a client cert & key is provided then configure TLS config accordingly.
	if len(cfg.CertFile) > 0 && len(cfg.KeyFile) == 0 {
	return nil, fmt.Errorf("client cert file %q specified without client key file", cfg.CertFile)
	} else if len(cfg.KeyFile) > 0 && len(cfg.CertFile) == 0 {
	return nil, fmt.Errorf("client key file %q specified without client cert file", cfg.KeyFile)
	} else if len(cfg.CertFile) > 0 && len(cfg.KeyFile) > 0 {
	cert, err := tls.LoadX509KeyPair(cfg.CertFile, cfg.KeyFile)
	if err != nil {
	return nil, fmt.Errorf("unable to use specified client cert (%s) & key (%s): %s", cfg.CertFile, cfg.KeyFile, err)
	}
	tlsConfig.Certificates = []tls.Certificate{cert}
	}
	tlsConfig.BuildNameToCertificate()

	return tlsConfig, nil
	}

	// TLSConfig configures the options for TLS connections.
	type TLSConfig struct {
	// The CA cert to use for the targets.
	CAFile string `yaml:"ca_file,omitempty"`
	// The client cert file for the targets.
	CertFile string `yaml:"cert_file,omitempty"`
	// The client key file for the targets.
	KeyFile string `yaml:"key_file,omitempty"`
	// Used to verify the hostname for the targets.
	ServerName string `yaml:"server_name,omitempty"`
	// Disable target certificate validation.
	InsecureSkipVerify bool `yaml:"insecure_skip_verify"`
	}

	// UnmarshalYAML implements the yaml.Unmarshaler interface.
	func (c *TLSConfig) UnmarshalYAML(unmarshal func(interface{}) error) error {
	type plain TLSConfig
	return unmarshal((*plain)(c))
	}

	func (c HTTPClientConfig) String() string {
	b, err := yaml.Marshal(c)
	if err != nil {
	return fmt.Sprintf("<error creating http client config string: %s>", err)
	}
	return string(b)
	}