chore: Fix error response with no body (#365)

Unauthenticated client handles error response without body

internal/login/client.go

@@ -0,0 +1,69 @@
+package login
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+
+	"github.com/launchdarkly/ldcli/internal/errors"
+)
+
+type UnauthenticatedClient interface {
+	MakeRequest(
+		method string,
+		path string,
+		data []byte,
+	) ([]byte, error)
+}
+
+type Client struct {
+	cliVersion string
+}
+
+func NewClient(cliVersion string) Client {
+	return Client{
+		cliVersion: cliVersion,
+	}
+}
+
+func (c Client) MakeRequest(
+	method string,
+	path string,
+	data []byte,
+) ([]byte, error) {
+	client := http.Client{}
+	req, _ := http.NewRequest(method, path, bytes.NewReader(data))
+	req.Header.Add("Content-Type", "application/json")
+	req.Header.Set("User-Agent", fmt.Sprintf("launchdarkly-cli/v%s", c.cliVersion))
+	res, err := client.Do(req)
+	if err != nil {
+		return nil, err
+	}
+
+	body, err := io.ReadAll(res.Body)
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+
+	if res.StatusCode < http.StatusBadRequest {
+		return body, nil
+	}
+
+	if len(body) > 0 {
+		return body, errors.NewError(string(body))
+	}
+
+	switch res.StatusCode {
+	case http.StatusMethodNotAllowed:
+		resp, _ := json.Marshal(map[string]string{
+			"code":    "method_not_allowed",
+			"message": "method not allowed",
+		})
+		return body, errors.NewError(string(resp))
+	default:
+		return body, errors.NewError(fmt.Sprintf("could not complete the request: %d", res.StatusCode))
+	}
+}

internal/login/client_test.go

@@ -0,0 +1,57 @@
+package login_test
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/launchdarkly/ldcli/internal/login"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestMakeRequest(t *testing.T) {
+	t.Run("with a successful response", func(t *testing.T) {
+		server := makeServer(t, http.StatusOK, `{"message": "success"}`)
+		defer server.Close()
+		c := login.NewClient("test-version")
+
+		response, err := c.MakeRequest("POST", server.URL, []byte(`{}`))
+
+		require.NoError(t, err)
+		assert.JSONEq(t, `{"message": "success"}`, string(response))
+	})
+
+	t.Run("with an error with a response body", func(t *testing.T) {
+		server := makeServer(t, http.StatusBadRequest, `{"message": "an error"}`)
+		defer server.Close()
+		c := login.NewClient("test-version")
+
+		_, err := c.MakeRequest("POST", server.URL, []byte(`{}`))
+
+		assert.EqualError(t, err, `{"message": "an error"}`)
+	})
+
+	t.Run("with a method not allowed status code and no body", func(t *testing.T) {
+		server := makeServer(t, http.StatusMethodNotAllowed, "")
+		defer server.Close()
+		c := login.NewClient("test-version")
+		expectedResponse := `{
+			"code": "method_not_allowed",
+			"message": "method not allowed"
+		}`
+
+		_, err := c.MakeRequest("POST", server.URL, []byte(`{}`))
+
+		assert.JSONEq(t, expectedResponse, err.Error())
+	})
+}
+
+func makeServer(t *testing.T, statusResponse int, responseBody string) *httptest.Server {
+	return httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		assert.Equal(t, "application/json", r.Header.Get("Content-Type"))
+		assert.Equal(t, "launchdarkly-cli/vtest-version", r.Header.Get("User-Agent"))
+		w.WriteHeader(statusResponse)
+		_, _ = w.Write([]byte(responseBody))
+	}))
+}

internal/login/login.go

@@ -1,11 +1,8 @@
 package login
 
 import (
-	"bytes"
 	"encoding/json"
 	"fmt"
-	"io"
-	"net/http"
 	"os"
 	"time"
 
@@ -29,53 +26,6 @@ type DeviceAuthorizationToken struct {
 	AccessToken string `json:"accessToken"`
 }
 
-type UnauthenticatedClient interface {
-	MakeRequest(
-		method string,
-		path string,
-		data []byte,
-	) ([]byte, error)
-}
-
-type Client struct {
-	cliVersion string
-}
-
-func NewClient(cliVersion string) Client {
-	return Client{
-		cliVersion: cliVersion,
-	}
-}
-
-func (c Client) MakeRequest(
-	method string,
-	path string,
-	data []byte,
-) ([]byte, error) {
-	client := http.Client{}
-
-	req, _ := http.NewRequest(method, path, bytes.NewReader(data))
-	req.Header.Add("Content-type", "application/json")
-	req.Header.Set("User-Agent", fmt.Sprintf("launchdarkly-cli/v%s", c.cliVersion))
-
-	res, err := client.Do(req)
-	if err != nil {
-		return nil, err
-	}
-
-	body, err := io.ReadAll(res.Body)
-	if err != nil {
-		return nil, err
-	}
-	defer res.Body.Close()
-
-	if res.StatusCode >= 400 {
-		return body, errors.NewError(string(body))
-	}
-
-	return body, nil
-}
-
 // FetchDeviceAuthorization makes a request to create a device authorization that will later be
 // used to set a local access token if the user grants access.
 func FetchDeviceAuthorization(

internal/resources/client.go

@@ -29,7 +29,7 @@ func (c ResourcesClient) MakeRequest(accessToken, method, path, contentType stri
 
 	req, _ := http.NewRequest(method, path, bytes.NewReader(data))
 	req.Header.Add("Authorization", accessToken)
-	req.Header.Add("Content-type", contentType)
+	req.Header.Add("Content-Type", contentType)
 	req.Header.Set("User-Agent", fmt.Sprintf("launchdarkly-cli/v%s", c.cliVersion))
 	if isBeta {
 		req.Header.Set("LD-API-Version", "beta")