Return error message when query share link info (#698)

* Return rsp content when query share link info

* Add parse error message

---------

Co-authored-by: 杨赫然 <heran.yang@seafile.com>

fileserver/fileop.go

@@ -355,12 +355,13 @@ func checkFileAccess(repoID, token, cookie, filePath, op string) (string, *appEr
 	}
 	status, body, err := utils.HttpCommon("POST", url, header, bytes.NewReader(msg))
 	if err != nil {
+		if status != http.StatusInternalServerError {
+			msg := "No permission to access file\n"
+			return "", &appError{nil, msg, http.StatusForbidden}
+		} else {
 			err := fmt.Errorf("failed to get access token info: %v", err)
 			return "", &appError{err, "", http.StatusInternalServerError}
 		}
-	if status != http.StatusOK {
-		msg := "No permission to access file\n"
-		return "", &appError{nil, msg, http.StatusForbidden}
 	}
 
 	info := new(UserInfo)
@@ -3651,12 +3652,12 @@ func queryShareLinkInfo(token, cookie, opType string) (*ShareLinkInfo, *appError
 	}
 	status, body, err := utils.HttpCommon("GET", url, header, nil)
 	if err != nil {
+		if status != http.StatusInternalServerError {
+			return nil, &appError{nil, string(body), status}
+		} else {
 			err := fmt.Errorf("failed to get share link info: %v", err)
 			return nil, &appError{err, "", http.StatusInternalServerError}
 		}
-	if status != http.StatusOK {
-		msg := "Link token not found"
-		return nil, &appError{nil, msg, http.StatusForbidden}
 	}
 
 	info := new(ShareLinkInfo)

fileserver/utils/http.go

@@ -2,6 +2,7 @@ package utils
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
@@ -25,22 +26,19 @@ func HttpCommon(method, url string, header map[string][]string, reader io.Reader
 	defer cancel()
 	req, err := http.NewRequestWithContext(ctx, method, url, reader)
 	if err != nil {
-		return -1, nil, err
+		return http.StatusInternalServerError, nil, err
 	}
 	req.Header = header
 
 	rsp, err := http.DefaultClient.Do(req)
 	if err != nil {
-		return -1, nil, err
+		return http.StatusInternalServerError, nil, err
 	}
 	defer rsp.Body.Close()
 
-	if rsp.StatusCode == http.StatusNotFound {
-		return rsp.StatusCode, nil, fmt.Errorf("url %s not found", url)
-	}
-
 	if rsp.StatusCode != http.StatusOK {
-		return rsp.StatusCode, nil, fmt.Errorf("bad response %d for %s", rsp.StatusCode, url)
+		errMsg := parseErrorMessage(rsp.Body)
+		return rsp.StatusCode, errMsg, fmt.Errorf("bad response %d for %s", rsp.StatusCode, url)
 	}
 
 	body, err := io.ReadAll(rsp.Body)
@@ -48,5 +46,23 @@ func HttpCommon(method, url string, header map[string][]string, reader io.Reader
 		return rsp.StatusCode, nil, err
 	}
 
-	return rsp.StatusCode, body, nil
+	return http.StatusOK, body, nil
+}
+
+func parseErrorMessage(r io.Reader) []byte {
+	body, err := io.ReadAll(r)
+	if err != nil {
+		return nil
+	}
+	var objs map[string]string
+	err = json.Unmarshal(body, &objs)
+	if err != nil {
+		return body
+	}
+	errMsg, ok := objs["error_msg"]
+	if ok {
+		return []byte(errMsg)
+	}
+
+	return body
 }

server/access-file.c

@@ -1823,11 +1823,22 @@ access_link_cb(evhtp_request_t *req, void *arg)
     token = parts[1];
 
     const char *cookie = evhtp_kv_find (req->headers_in, "Cookie");
-    info = http_tx_manager_query_share_link_info (token, cookie, "file");
+    int status = HTTP_OK;
+    char *err_msg = NULL;
+    info = http_tx_manager_query_share_link_info (token, cookie, "file", &status, &err_msg);
     if (!info) {
-        error_str = "Link token not found\n";
-        error_code = EVHTP_RES_FORBIDDEN;
-        goto out;
+        g_strfreev (parts);
+        if (status != HTTP_OK) {
+            evbuffer_add_printf(req->buffer_out, "%s\n", err_msg);
+            evhtp_send_reply(req, status);
+        } else {
+            error_str = "Internal server error\n";
+            error_code = EVHTP_RES_SERVERR;
+            evbuffer_add_printf(req->buffer_out, "%s\n", error_str);
+            evhtp_send_reply(req, error_code);
+        }
+        g_free (err_msg);
+        return;
     }
 
     repo_id = seafile_share_link_info_get_repo_id (info);

server/http-tx-mgr.c

@@ -567,8 +567,39 @@ out:
     return info;
 }
 
+char *
+parse_error_message (const char *rsp_content, int rsp_size)
+{
+    json_t *object;
+    json_error_t jerror;
+    const char *err_msg = NULL;
+    char *ret = NULL;
+
+    if (!rsp_content) {
+        return NULL;
+    }
+
+    object = json_loadb (rsp_content, rsp_size, 0, &jerror);
+    if (!object) {
+        ret = g_strdup (rsp_content);
+        return ret;
+    }
+
+    err_msg = json_object_get_string_member (object, "error_msg");
+    if (!err_msg) {
+        ret = g_strdup (rsp_content);
+        goto out;
+    }
+    ret = g_strdup (err_msg);
+
+out:
+    json_decref (object);
+
+    return ret;
+}
+
 SeafileShareLinkInfo *
-http_tx_manager_query_share_link_info (const char *token, const char *cookie, const char *type)
+http_tx_manager_query_share_link_info (const char *token, const char *cookie, const char *type, int *status, char **err_msg)
 {
     Connection *conn = NULL;
     char *cookie_header;
@@ -609,7 +640,9 @@ http_tx_manager_query_share_link_info (const char *token, const char *cookie, co
         goto out;
     }
 
+    *status = rsp_status;
     if (rsp_status != HTTP_OK) {
+        *err_msg = parse_error_message (rsp_content, rsp_size);
         goto out;
     }
 

server/http-tx-mgr.h

@@ -50,7 +50,8 @@ char *
 http_tx_manager_get_nickname (const char *modifier);
 
 SeafileShareLinkInfo *
-http_tx_manager_query_share_link_info (const char *token, const char *cookie, const char *type);
+http_tx_manager_query_share_link_info (const char *token, const char *cookie, const char *type,
+                                       int *status, char **err_msg);
 
 int
 http_tx_manager_check_file_access (const char *repo_id, const char *token, const char *cookie,