net/http package ~GoConference 2017 Spring~

Transcript

1. net/http package
   GoConference 2017 Spring
   

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2. kaneshin (Shintaro Kaneko)
   - CTO of Eureka, Inc.
   - Twitter: @kaneshin0120
   - Gopher, Vimmer, Photographer, Mathematician
   

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3. 'BDFCPPLΛར༻ͨ͠
   ࿀Ѫɾࠗ׆ϚονϯάαʔϏε
   

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4. Learning golang from code
   

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5. Today's special
   var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
   time.Sleep(time.Hour)
   w.Write([]byte("Hello world!"))
   }
   func main() {
   s := httptest.NewServer(http.HandlerFunc(sleepHandler))
   defer s.Close()
   resp, err := http.Get(s.URL)
   if err != nil {
   return
   }
   defer resp.Body.Close()
   body, err := ioutil.ReadAll(resp.Body)
   

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6. net/http/httptest
   

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7. net/http/httptest
   var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
   time.Sleep(time.Hour)
   w.Write([]byte("Hello world!"))
   }
   func main() {
   s := httptest.NewServer(http.HandlerFunc(sleepHandler))
   defer s.Close()
   resp, err := http.Get(s.URL)
   if err != nil {
   return
   }
   defer resp.Body.Close()
   body, err := ioutil.ReadAll(resp.Body)
   

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8. net/http/httptest
   var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
   time.Sleep(time.Hour)
   w.Write([]byte("Hello world!"))
   }
   func main() {
   s := httptest.NewServer(http.HandlerFunc(sleepHandler))
   defer s.Close()
   resp, err := http.Get(s.URL)
   if err != nil {
   return
   }
   defer resp.Body.Close()
   body, err := ioutil.ReadAll(resp.Body)
   http://blog.kaneshin.co/entry/2016/12/02/200108
   net/http/httptest.Server
   net/http/httptest.ResponseRecorder
   

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9. net/http/httptest
   var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
   time.Sleep(time.Hour)
   w.Write([]byte("Hello world!"))
   }
   func main() {
   s := httptest.NewServer(http.HandlerFunc(sleepHandler))
   defer s.Close()
   resp, err := http.Get(s.URL)
   if err != nil {
   return
   }
   defer resp.Body.Close()
   body, err := ioutil.ReadAll(resp.Body)
   

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10. net/http.ResponseWriter
    

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11. net/http.ResponseWriter
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    

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12. net/http.ResponseWriter
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    

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13. net/http.ResponseWriter
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    type ResponseWriter interface {
    // Changing the header map after a call to WriteHeader (or
    // Write) has no effect unless the modified headers are trailers.
    Header() Header
    Write([]byte) (int, error)
    // If WriteHeader is not called explicitly, the first call to Write
    // will trigger an implicit WriteHeader(http.StatusOK).
    WriteHeader(int)
    }
    

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14. net/http.ResponseWriter
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    type ResponseWriter interface {
    // Changing the header map after a call to WriteHeader (or
    // Write) has no effect unless the modified headers are trailers.
    Header() Header
    Write([]byte) (int, error)
    // If WriteHeader is not called explicitly, the first call to Write
    // will trigger an implicit WriteHeader(http.StatusOK).
    WriteHeader(int)
    }
    

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15. net/http.ResponseWriter
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    type ResponseWriter interface {
    // Changing the header map after a call to WriteHeader (or
    // Write) has no effect unless the modified headers are trailers.
    Header() Header
    Write([]byte) (int, error)
    // If WriteHeader is not called explicitly, the first call to Write
    // will trigger an implicit WriteHeader(http.StatusOK).
    WriteHeader(int)
    }
    

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16. net/http.ResponseWriter
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    type ResponseWriter interface {
    // Changing the header map after a call to WriteHeader (or
    // Write) has no effect unless the modified headers are trailers.
    Header() Header
    Write([]byte) (int, error)
    // If WriteHeader is not called explicitly, the first call to Write
    // will trigger an implicit WriteHeader(http.StatusOK).
    WriteHeader(int)
    }
    var handler = func(w http.ResponseWriter, r *http.Request) {
    }
    

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17. net/http.ResponseWriter
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    type ResponseWriter interface {
    // Changing the header map after a call to WriteHeader (or
    // Write) has no effect unless the modified headers are trailers.
    Header() Header
    Write([]byte) (int, error)
    // If WriteHeader is not called explicitly, the first call to Write
    // will trigger an implicit WriteHeader(http.StatusOK).
    WriteHeader(int)
    }
    var handler = func(w http.ResponseWriter, r *http.Request) {
    w.Write([]byte("Hello world!"))
    }
    

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18. net/http.ResponseWriter
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    type ResponseWriter interface {
    // Changing the header map after a call to WriteHeader (or
    // Write) has no effect unless the modified headers are trailers.
    Header() Header
    Write([]byte) (int, error)
    // If WriteHeader is not called explicitly, the first call to Write
    // will trigger an implicit WriteHeader(http.StatusOK).
    WriteHeader(int)
    }
    var handler = func(w http.ResponseWriter, r *http.Request) {
    w.WriteHeader(http.StatusCreated)
    w.Write([]byte("Hello world!"))
    }
    

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19. net/http.ResponseWriter
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    type ResponseWriter interface {
    // Changing the header map after a call to WriteHeader (or
    // Write) has no effect unless the modified headers are trailers.
    Header() Header
    Write([]byte) (int, error)
    // If WriteHeader is not called explicitly, the first call to Write
    // will trigger an implicit WriteHeader(http.StatusOK).
    WriteHeader(int)
    }
    var handler = func(w http.ResponseWriter, r *http.Request) {
    w.Header("X-Foo", "bar")
    w.WriteHeader(http.StatusCreated)
    w.Write([]byte("Hello world!"))
    }
    

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20. net/http.ResponseWriter
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    type ResponseWriter interface {
    // Changing the header map after a call to WriteHeader (or
    // Write) has no effect unless the modified headers are trailers.
    Header() Header
    Write([]byte) (int, error)
    // If WriteHeader is not called explicitly, the first call to Write
    // will trigger an implicit WriteHeader(http.StatusOK).
    WriteHeader(int)
    }
    var handler = func(w http.ResponseWriter, r *http.Request) {
    w.Header("X-Foo", "bar")
    w.WriteHeader(http.StatusCreated)
    w.Write([]byte("Hello world!"))
    // ❌ w.WriteHeader(http.StatusBadRequest) after a call to Write
    // ❌ w.Header("X-Foo", "qux") after a call to WriteHeader
    }
    

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21. net/http.ResponseWriter
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    

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22. net/http.Client
    

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23. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    

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24. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    

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25. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    /// package http
    

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26. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    /// package http
    func Get(url string) (resp *Response, err error) {
    return DefaultClient.Get(url)
    }
    

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27. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    /// package http
    func Get(url string) (resp *Response, err error) {
    return DefaultClient.Get(url)
    }
    var DefaultClient = &Client{}
    

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28. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    /// package http
    func Get(url string) (resp *Response, err error) {
    return DefaultClient.Get(url)
    }
    var DefaultClient = &Client{}
    type Client struct {
    Transport RoundTripper
    CheckRedirect func(req *Request, via []*Request) error
    Jar CookieJar
    Timeout time.Duration
    }
    

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29. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    var DefaultClient = &Client{}
    type Client struct {
    Transport RoundTripper
    CheckRedirect func(req *Request, via []*Request) error
    Jar CookieJar
    Timeout time.Duration
    }
    

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30. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    // A Client is an HTTP client. Its zero value (DefaultClient) is a
    // usable client that uses DefaultTransport.
    //
    // The Client's Transport typically has internal state (cached TCP
    // connections), so Clients should be reused instead of created as
    // needed. Clients are safe for concurrent use by multiple goroutines.
    // ...
    var DefaultClient = &Client{}
    type Client struct {
    Transport RoundTripper
    CheckRedirect func(req *Request, via []*Request) error
    Jar CookieJar
    Timeout time.Duration
    }
    

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31. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    // A Client is an HTTP client. Its zero value (DefaultClient) is a
    // usable client that uses DefaultTransport.
    //
    // The Client's Transport typically has internal state (cached TCP
    // connections), so Clients should be reused instead of created as
    // needed. Clients are safe for concurrent use by multiple goroutines.
    // ...
    var DefaultClient = &Client{}
    type Client struct {
    Transport RoundTripper
    CheckRedirect func(req *Request, via []*Request) error
    Jar CookieJar
    Timeout time.Duration
    }
    

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32. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    /// package http
    var DefaultTransport RoundTripper = &Transport{
    Proxy: ProxyFromEnvironment,
    DialContext: (&net.Dialer{
    Timeout: 30 * time.Second,
    KeepAlive: 30 * time.Second,
    DualStack: true,
    }).DialContext,
    MaxIdleConns: 100,
    IdleConnTimeout: 90 * time.Second,
    TLSHandshakeTimeout: 10 * time.Second,
    ExpectContinueTimeout: 1 * time.Second,
    }
    

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33. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    // A Client is an HTTP client. Its zero value (DefaultClient) is a
    // usable client that uses DefaultTransport.
    //
    // The Client's Transport typically has internal state (cached TCP
    // connections), so Clients should be reused instead of created as
    // needed. Clients are safe for concurrent use by multiple goroutines.
    // ...
    var DefaultClient = &Client{}
    type Client struct {
    Transport RoundTripper
    CheckRedirect func(req *Request, via []*Request) error
    Jar CookieJar
    Timeout time.Duration
    }
    

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34. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    // A Client is an HTTP client. Its zero value (DefaultClient) is a
    // usable client that uses DefaultTransport.
    //
    // The Client's Transport typically has internal state (cached TCP
    // connections), so Clients should be reused instead of created as
    // needed. Clients are safe for concurrent use by multiple goroutines.
    // ...
    var DefaultClient = &Client{}
    type Client struct {
    Transport RoundTripper
    CheckRedirect func(req *Request, via []*Request) error
    Jar CookieJar
    Timeout time.Duration
    }
    

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35. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    // A Client is an HTTP client. Its zero value (DefaultClient) is a
    // usable client that uses DefaultTransport.
    //
    // The Client's Transport typically has internal state (cached TCP
    // connections), so Clients should be reused instead of created as
    // needed. Clients are safe for concurrent use by multiple goroutines.
    // ...
    var DefaultClient = &Client{}
    type Client struct {
    Transport RoundTripper
    CheckRedirect func(req *Request, via []*Request) error
    Jar CookieJar
    Timeout time.Duration
    }
    

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36. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    // A Client is an HTTP client. Its zero value (DefaultClient) is a
    // usable client that uses DefaultTransport.
    //
    // The Client's Transport typically has internal state (cached TCP
    // connections), so Clients should be reused instead of created as
    // needed. Clients are safe for concurrent use by multiple goroutines.
    // ...
    var DefaultClient = &Client{}
    type Client struct {
    Transport RoundTripper
    CheckRedirect func(req *Request, via []*Request) error
    Jar CookieJar
    // A Timeout of zero means no timeout.
    Timeout time.Duration
    }
    

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37. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    // A Client is an HTTP client. Its zero value (DefaultClient) is a
    // usable client that uses DefaultTransport.
    //
    // The Client's Transport typically has internal state (cached TCP
    // connections), so Clients should be reused instead of created as
    // needed. Clients are safe for concurrent use by multiple goroutines.
    // ...
    var DefaultClient = &Client{}
    type Client struct {
    Transport RoundTripper
    CheckRedirect func(req *Request, via []*Request) error
    Jar CookieJar
    // A Timeout of zero means no timeout.
    Timeout time.Duration
    }
    func init() {
    }
    

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38. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    // A Client is an HTTP client. Its zero value (DefaultClient) is a
    // usable client that uses DefaultTransport.
    //
    // The Client's Transport typically has internal state (cached TCP
    // connections), so Clients should be reused instead of created as
    // needed. Clients are safe for concurrent use by multiple goroutines.
    // ...
    var DefaultClient = &Client{}
    type Client struct {
    Transport RoundTripper
    CheckRedirect func(req *Request, via []*Request) error
    Jar CookieJar
    // A Timeout of zero means no timeout.
    Timeout time.Duration
    }
    func init() {
    http.DefaultClient.Timeout = 30 * time.Second
    }
    

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39. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    // A Client is an HTTP client. Its zero value (DefaultClient) is a
    // usable client that uses DefaultTransport.
    //
    // The Client's Transport typically has internal state (cached TCP
    // connections), so Clients should be reused instead of created as
    // needed. Clients are safe for concurrent use by multiple goroutines.
    // ...
    var DefaultClient = &Client{}
    type Client struct {
    Transport RoundTripper
    CheckRedirect func(req *Request, via []*Request) error
    Jar CookieJar
    // A Timeout of zero means no timeout.
    Timeout time.Duration
    }
    func init() {
    http.DefaultClient.Timeout = 30 * time.Second
    // Modify if needed.
    http.DefaultTransport = &http.Transport{
    // ...
    }
    }
    

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40. net/http.Client
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    

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41. Others
    

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42. net/http.Response.Body.Close()
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    

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43. net/http.Response.Body.Close()
    var sleepHandler = func(w http.ResponseWriter, r *http.Request) {
    time.Sleep(time.Hour)
    w.Write([]byte("Hello world!"))
    }
    func main() {
    s := httptest.NewServer(http.HandlerFunc(sleepHandler))
    defer s.Close()
    resp, err := http.Get(s.URL)
    if err != nil {
    return
    }
    defer resp.Body.Close()
    body, err := ioutil.ReadAll(resp.Body)
    

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44. net/http.Constants
    

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45. Settable net/http.Client
    type FooClient struct {
    HTTPClient *http.Client
    }
    /// OR
    type FooClient struct {
    httpClient *http.Client
    }
    func NewFooClient(httpClient *http.Client) FooClient {
    return FooClient{
    httpClient: httpClient,
    }
    }
    

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46. Summaries
    

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47. Summaries
    • net/http/httptest
    • net/http.ResponseWriter
    • net/http.Client
    • net/http.Response.Body.Close()
    • net/http.Constants
    • Settable net/http.Client
    

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48. Thank you
    $SFEJU/"4"&BSUI0CTFSWBUPSZ/0""/(%$
    

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