Expose more useful http error info

Use a custom error type so that the error status and body can be read
from the calling code.

The error gets wrapped so you'll need to use errors.As() to get
the body.

Author: psanford

error.go

@@ -30,7 +30,7 @@ func CreateChartTimeError() error {
 // CreateRemoteError returns an error
 // with a message about a remote api problem.
 func CreateRemoteError(e error) error {
-	return fmt.Errorf("code: %s, detail: %s", remoteErrorCode, e.Error())
+	return fmt.Errorf("code: %s, detail: %w", remoteErrorCode, e)
 }
 
 // CreateRemoteErrorS returns an error

finance.go

@@ -3,6 +3,7 @@ package finance
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	"io/ioutil"
 	"log"
 	"net/http"
@@ -226,7 +227,11 @@ func (s *BackendConfiguration) Do(req *http.Request, v interface{}) error {
 		if LogLevel > 0 {
 			Logger.Printf("API error: %q\n", resBody)
 		}
-		return CreateRemoteErrorS("error response recieved from upstream api")
+		return &RemoteError{
+			Msg:        "error response recieved from upstream api",
+			StatusCode: res.StatusCode,
+			Body:       string(resBody),
+		}
 	}
 
 	if LogLevel > 2 {
@@ -239,3 +244,13 @@ func (s *BackendConfiguration) Do(req *http.Request, v interface{}) error {
 
 	return nil
 }
+
+type RemoteError struct {
+	Msg        string
+	StatusCode int
+	Body       string
+}
+
+func (e *RemoteError) Error() string {
+	return fmt.Sprintf("status: %d, detail: %s", e.StatusCode, e.Msg)
+}