rek
An easy HTTP client for Go inspired by Requests, plus all the Go-specific goodies you'd hope for in a client. Here's an example:
// GET request
res, _ := rek.Get("https://httpbin.org/get")
fmt.Println(res.StatusCode())
body, _ := rek.BodyAsString(res.Body())
fmt.Println(body)
// POST request
type Comment struct {
Username string `json:"username"`
Body string `json:"body"`
}
res, _ := rek.Post("https://httpbin.org/post",
rek.Json(Comment{Username: "genesiskel", Body: "This movie sucked. Two thumbs down."}),
rek.Headers(map[string]string{"My-Custom-Header": "foo,bar,baz"}),
rek.BasicAuth("user", "pass"),
rek.Timeout(5 * time.Second),
)
fmt.Println(res.StatusCode())
body, _ := rek.BodyAsString(res.Body())
fmt.Println(body)
Responses
The Response
struct has the following methods:
Method | Description | Return type |
---|---|---|
StatusCode() |
HTTP status code, e.g. 200, 400 | int |
Body() |
The HTTP response body as a reader | io.ReadCloser |
Headers() |
The response headers | map[string]string |
Encoding() |
The content encoding of the response body, e.g. gzip |
[]string |
ContentType() |
The value of the Content-Type header |
string |
Raw() |
The unmodified *http.Response |
*http.Response |
Cookies() |
The cookies attached to the response | []*http.Cookie |
ContentLength() |
The length of the response | int64 |
Status() |
The status of the response, e.g. 200 OK |
string |
HTTP response body
Keep in mind that the HTTP response body can only be read once. This is one area in which rek does not directly correspond to the Requests API. And so this, for example, won't work the way you might want:
res, _ := rek.Get("https://httpbin.org/get")
bs1, _ := ioutil.ReadAll(res.Body()) // Non-empty byte slice
bs2, _ := ioutil.ReadAll(res.Body()) // Empty byte slice
If you'd like to use the response body more than once, store it in a variable rather than re-accessing the body.
Helper methods
There are two simple helper methods for working with the response body:
Function | Return types |
---|---|
BodyAsString(io.ReadCloser) |
(string, error) |
BodyAsBytes(io.ReadCloser) |
([]byte, error) |
Bear in mind the caveat mentioned above, that the request body can only be read once, still holds. Here are some examples:
res, _ := rek.Get("https://httpbin.org/get")
s1, _ := rek.BodyAsString(res.Body()) // body is read here
s2, _ := rek.BodyAsString(res.Body()) // s2 is an empty string
Non-standard methods
rek natively supports the methods GET
, POST
, PUT
, DELETE
, PATCH
, and HEAD
. If you'd like to use a method that's not directly supported, you can use the Do
function:
res, err := rek.Do("SOMEOTHERMETHOD", rek.Timeout(10 * time.Second))
Options
Headers
headers := map[string]string{
"My-Custom-Header": "foo,bar,baz",
}
res, err := rek.Post("https://httpbin.org/post", rek.Headers(headers))
JSON
Pass in any struct:
type Comment struct {
ID int64 `json:"id"`
Body string `json:"body"`
Timestamp time.Time `json:"timestamp"`
}
comment := Comment{ID:47, Body:"Cool movie!", Timestamp: time.Now()}
res, err := rek.Post("https://httpbin.org/post", rek.Json(comment))
Request headers are automatically updated to include
Content-Type
asapplication/json;charset=utf-8
.
Request timeout
res, err := rek.Get("https://httpbin.org/get", rek.Timeout(5 * time.Second))
Form data
form := map[string]string{
"foo": "bar",
"baq": "baz",
}
res, err := rek.Put("https://httpbin.org/put", rek.FormData(form))
Request headers are automatically updated to include
Content-Type
asapplication/x-www-form-urlencoded
.
File upload
fieldName := "file"
filepath := "docs/README.md"
params := nil
res, err := rek.Post("https:/httpbin.org/post", rek.File(fieldName, filepath, params))
Request headers are automatically updated to include
Content-Type
asmultipart/form-data; boundary=...
.
Basic auth
username, password := "user", "pass"
res, _ := rek.Get(fmt.Sprintf("https://httpbin.org/basic-auth/%s/%s", username, password),
rek.BasicAuth(username, password))
fmt.Println(res.StatusCode()) // 200
res, _ := rek.Get(fmt.Sprintf("https://httpbin.org/basic-auth/%s/other", username, password),
rek.BasicAuth(username, password))
fmt.Println(res.StatusCode()) // 401
Data
Takes any input and serializes it to a []byte
:
data := map[string]interface{
"age": 38,
"name": "Luc",
}
res, err := rek.Post("https://httpbin.org/post", rek.Data(data))
Request headers are automatically updated to include
Content-Type
asapplication/octet-stream
.
User agent
res, err := rek.Post("https://httpbin.org/post", rek.UserAgent("ThisGuy"))
Bearer (useful for JSON Web Tokens)
token := "... token ..."
res, err := rek.Post("https://httpbin.org/post", rek.Bearer(token))
Request modifier
Supply a function that modifies the *http.Request
(after all other supplied options have been applied to the request):
modifier := func(r *http.Request) {
// Do whatever you want with the request
}
res, err := rek.Get("https://httpbin.org/get", rek.RequestModifier(modifier))
Accept
Apply an Accept
header to the request:
res, err := rek.Get("https://httpbin.org/get", rek.Accept("application/tar+gzip"))
API key
Add an API key to the request as an Authorization
header (where the value is Basic ${KEY}
):
res, err := rek.Get("https://some-secure-api.io", rek.ApiKey("a1b2c3..."))
Context
Supply a Context
to the request:
ctx, cancel := context.WithCancel(context.Background())
res, err := rek.Get("https://long-winded-api.io", rek.Context(ctx))
// Ugh, I don't want this request to happen anymore
cancel()
OAuth2
You can add an OAuth2 configuration and token to your request:
conf := &oauth2.Config{
ClientID: "YOUR_CLIENT_ID",
ClientSecret: "YOUR_CLIENT_SECRET",
Scopes: []string{"SCOPE1", "SCOPE2"},
Endpoint: oauth2.Endpoint{
AuthURL: "https://provider.com/o/oauth2/auth",
TokenURL: "https://provider.com/o/oauth2/token",
},
}
tok, err := conf.Exchange(ctx, code)
// handle error
res, err := rek.Get("https://oauth2-protected-site.com", rek.OAuth2(conf, tok))
Custom client
You can pass in your own *http.Client
as the basis for the request:
client := &http.Client{
// Custom attributes
}
res, err := rek.Get("https://httpbin.org/get", rek.Client(client))
Validation
It's important to bear in mind that rek provides no validation for the options that you provide on a specific request and doesn't provide any constraints on which options can be used with which request method. Some options may not make sense for some methods, e.g. request JSON on a HEAD
request, but I leave it up to the end user to supply their own constraints. One exception is that the request body can only be set once. If you attempt to set it more than once you'll get a ErrRequestBodySetMultipleTimes
error. This, for example, will throw that error:
comment := Comment{Body: "This movie sucked"}
_, err := rek.Post("https://httpbin.org/post",
rek.Json(comment),
rek.FormData(map[string]string{"foo": "bar"}))
fmt.Println(errors.Is(err, rek.ErrRequestBodySetMultipleTimes)) // true