feat: parse discord errors response into readable format

Author: topi314

rest/rest_error.go

@@ -3,7 +3,10 @@ package rest
 import (
 	"errors"
 	"fmt"
+	"maps"
 	"net/http"
+	"slices"
+	"strings"
 
 	"github.com/disgoorg/json/v2"
 )
@@ -55,7 +58,11 @@ func (e *Error) Is(target error) bool {
 // Error returns the error formatted as string
 func (e *Error) Error() string {
 	if e.Code != 0 {
-		return fmt.Sprintf("%d: %s", e.Code, e.Message)
+		msg := fmt.Sprintf("%d: %s", e.Code, e.Message)
+		if e.Code == 50035 {
+			msg += fmt.Sprintf("\n%s", printErrors(e.Errors))
+		}
+		return msg
 	}
 	return fmt.Sprintf("Status: %s, Body: %s", e.Response.Status, string(e.RsBody))
 }
@@ -64,3 +71,37 @@ func (e *Error) Error() string {
 func (e *Error) String() string {
 	return e.Error()
 }
+
+func printErrors(errors json.RawMessage) string {
+	var m map[string]any
+	if err := json.Unmarshal(errors, &m); err != nil {
+		return ""
+	}
+
+	return parseErrors("", m)
+}
+
+func parseErrors(prefix string, err map[string]any) string {
+	if errs, ok := err["_errors"]; ok {
+		var s []string
+		for _, e := range errs.([]any) {
+			m := e.(map[string]any)
+			s = append(s, fmt.Sprintf("%s -> %s: %s", prefix, m["code"], m["message"]))
+		}
+		return strings.Join(s, "\n")
+	}
+
+	var s []string
+	for _, k := range slices.Sorted(maps.Keys(err)) {
+		m := err[k].(map[string]any)
+
+		nextPrefix := prefix
+		if nextPrefix != "" {
+			nextPrefix += " -> "
+		}
+
+		s = append(s, parseErrors(nextPrefix+k, m))
+	}
+
+	return strings.Join(s, "\n")
+}

rest/rest_error_test.go

@@ -0,0 +1,56 @@
+package rest
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/disgoorg/json/v2"
+)
+
+func TestError_Error(t *testing.T) {
+	data := []struct {
+		Name     string
+		TestFile string
+		Expected string
+	}{
+		{
+			Name:     "array error",
+			TestFile: "array_error.json",
+			Expected: "50035: Invalid Form Body\nactivities -> 0 -> platform -> BASE_TYPE_CHOICES: Value must be one of ('desktop', 'android', 'ios').\nactivities -> 0 -> type -> BASE_TYPE_CHOICES: Value must be one of (0, 1, 2, 3, 4, 5).",
+		},
+		{
+			Name:     "object error",
+			TestFile: "object_error.json",
+			Expected: "50035: Invalid Form Body\naccess_token -> BASE_TYPE_REQUIRED: This field is required",
+		},
+		{
+			Name:     "request error",
+			TestFile: "request_error.json",
+			Expected: "50035: Invalid Form Body\n -> APPLICATION_COMMAND_TOO_LARGE: Command exceeds maximum size (8000)",
+		},
+		{
+			Name:     "other error",
+			TestFile: "other_error.json",
+			Expected: "50035: Invalid Form Body\ndata -> components -> BASE_TYPE_MAX_LENGTH: Must be 5 or fewer in length.",
+		},
+	}
+
+	for _, d := range data {
+		t.Run(d.Name, func(t *testing.T) {
+			raw, err := os.ReadFile(filepath.Join("testdata", d.TestFile))
+			if err != nil {
+				t.Fatal(err)
+			}
+			var restErr *Error
+			if err = json.Unmarshal(raw, &restErr); err != nil {
+				t.Fatal(err)
+			}
+
+			actual := restErr.Error()
+			if actual != d.Expected {
+				t.Errorf("got %q, want %q", actual, d.Expected)
+			}
+		})
+	}
+}

rest/testdata/array_error.json

@@ -0,0 +1,26 @@
+{
+  "code": 50035,
+  "message": "Invalid Form Body",
+  "errors": {
+    "activities": {
+      "0": {
+        "platform": {
+          "_errors": [
+            {
+              "code": "BASE_TYPE_CHOICES",
+              "message": "Value must be one of ('desktop', 'android', 'ios')."
+            }
+          ]
+        },
+        "type": {
+          "_errors": [
+            {
+              "code": "BASE_TYPE_CHOICES",
+              "message": "Value must be one of (0, 1, 2, 3, 4, 5)."
+            }
+          ]
+        }
+      }
+    }
+  }
+}

rest/testdata/object_error.json

@@ -0,0 +1,14 @@
+{
+  "code": 50035,
+  "message": "Invalid Form Body",
+  "errors": {
+    "access_token": {
+      "_errors": [
+        {
+          "code": "BASE_TYPE_REQUIRED",
+          "message": "This field is required"
+        }
+      ]
+    }
+  }
+}

rest/testdata/other_error.json

@@ -0,0 +1,16 @@
+{
+  "code": 50035,
+  "message": "Invalid Form Body",
+  "errors": {
+    "data": {
+      "components": {
+        "_errors": [
+          {
+            "code": "BASE_TYPE_MAX_LENGTH",
+            "message": "Must be 5 or fewer in length."
+          }
+        ]
+      }
+    }
+  }
+}

rest/testdata/request_error.json

@@ -0,0 +1,12 @@
+{
+  "code": 50035,
+  "message": "Invalid Form Body",
+  "errors": {
+    "_errors": [
+      {
+        "code": "APPLICATION_COMMAND_TOO_LARGE",
+        "message": "Command exceeds maximum size (8000)"
+      }
+    ]
+  }
+}