ezhttp: CURL equivalent command helper

net/http/ezhttp/ezhttp.go

@@ -1,10 +1,10 @@
 // This package aims to wrap Go HTTP Client's request-response with sane defaults:
 //
-// - You are forced to consider timeouts by having to specify Context
-// - Instead of not considering non-2xx status codes as a failure, check that by default
-// (unless explicitly asked to)
-// - Sending and receiving JSON requires much less boilerplate, and on receiving JSON you
-// are forced to think whether to "allowUnknownFields"
+//  - You are forced to consider timeouts by having to specify Context
+//  - Instead of not considering non-2xx status codes as a failure, check that by default
+//  (unless explicitly asked to)
+//  - Sending and receiving JSON requires much less boilerplate, and on receiving JSON you
+//  are forced to think whether to "allowUnknownFields"
 package ezhttp
 
 import (
@@ -59,29 +59,46 @@ func (e ResponseStatusError) StatusCode() int {
  return e.statusCode
 }
 
+// returns *ResponseStatusError as error if non-2xx response (unless TolerateNon2xxResponse()).
+// error is not *ResponseStatusError for transport-level errors, content (JSON) marshaling errors etc
 func Get(ctx context.Context, url string, confPieces ...ConfigPiece) (*http.Response, error) {
  return do(ctx, http.MethodGet, url, confPieces...)
 }
 
+// returns *ResponseStatusError as error if non-2xx response (unless TolerateNon2xxResponse()).
+// error is not *ResponseStatusError for transport-level errors, content (JSON) marshaling errors etc
 func Post(ctx context.Context, url string, confPieces ...ConfigPiece) (*http.Response, error) {
  return do(ctx, http.MethodPost, url, confPieces...)
 }
 
+// returns *ResponseStatusError as error if non-2xx response (unless TolerateNon2xxResponse()).
+// error is not *ResponseStatusError for transport-level errors, content (JSON) marshaling errors etc
 func Put(ctx context.Context, url string, confPieces ...ConfigPiece) (*http.Response, error) {
  return do(ctx, http.MethodPut, url, confPieces...)
 }
 
+// returns *ResponseStatusError as error if non-2xx response (unless TolerateNon2xxResponse()).
+// error is not *ResponseStatusError for transport-level errors, content (JSON) marshaling errors etc
 func Head(ctx context.Context, url string, confPieces ...ConfigPiece) (*http.Response, error) {
  return do(ctx, http.MethodHead, url, confPieces...)
 }
 
+// returns *ResponseStatusError as error if non-2xx response (unless TolerateNon2xxResponse()).
+// error is not *ResponseStatusError for transport-level errors, content (JSON) marshaling errors etc
 func Del(ctx context.Context, url string, confPieces ...ConfigPiece) (*http.Response, error) {
  return do(ctx, http.MethodDelete, url, confPieces...)
 }
 
-// returns *ResponseStatusError as error if non-2xx response (unless TolerateNon2xxResponse()).
-// error is not *ResponseStatusError for transport-level errors, content (JSON) marshaling errors etc
 func do(ctx context.Context, method string, url string, confPieces ...ConfigPiece) (*http.Response, error) {
+ conf, err := configure(ctx, method, url, confPieces...)
+ if err != nil {
+ return nil, err
+ }
+
+ return doRequest(conf)
+}
+
+func configure(ctx context.Context, method string, url string, confPieces ...ConfigPiece) (*Config, error) {
  conf := &Config{
  Client: http.DefaultClient,
  }
@@ -129,13 +146,17 @@ func do(ctx context.Context, method string, url string, confPieces ...ConfigPiec
  return nil, conf.Abort
  }
 
- resp, err := conf.Client.Do(req)
+ return conf, nil
+}
+
+func doRequest(conf *Config) (*http.Response, error) {
+ resp, err := conf.Client.Do(conf.Request)
  if err != nil {
  return resp, err // this is a transport-level error
  }
 
  // 304 is an error unless caller is expecting such response by sending caching headers
- if resp.StatusCode == http.StatusNotModified && req.Header.Get("If-None-Match") != "" {
+ if resp.StatusCode == http.StatusNotModified && conf.Request.Header.Get("If-None-Match") != "" {
  return resp, nil
  }
 

net/http/ezhttp/helpers.go

@@ -1,7 +1,9 @@
 package ezhttp
 
 import (
+ "context"
  "crypto/tls"
+ "fmt"
  "net/http"
 )
 
@@ -26,3 +28,22 @@ func ErrorIs(err error, statusCode int) bool {
  return false
  }
 }
+
+// for `method` please use `net/http` "enum" (quotes because it's not declared as such)
+func CURLEquivalent(method string, url string, confPieces ...ConfigPiece) ([]string, error) {
+ conf, err := configure(context.Background(), http.MethodGet, url, confPieces...)
+ if err != nil {
+ return nil, err
+ }
+
+ cmd := []string{"curl", "--request=" + method}
+
+ for key, values := range conf.Request.Header {
+ // FIXME: doesn't take into account multiple values
+ cmd = append(cmd, fmt.Sprintf("--header=%s=%s", key, values[0]))
+ }
+
+ cmd = append(cmd, url)
+
+ return cmd, nil
+}

net/http/ezhttp/helpers_test.go

@@ -0,0 +1,16 @@
+package ezhttp
+
+import (
+ "net/http"
+ "strings"
+ "testing"
+
+ . "github.com/function61/gokit/builtin"
+ "github.com/function61/gokit/testing/assert"
+)
+
+func TestCURLEquivalent(t *testing.T) {
+ curlCmd := Must(CURLEquivalent(http.MethodPost, "https://example.net/hello", Header("x-correlation-id", "123")))
+
+ assert.Equal(t, strings.Join(curlCmd, " "), "curl --request=POST --header=X-Correlation-Id=123 https://example.net/hello")
+}