added the feature to get join group info by invite link

src/api/api.go

@@ -1431,6 +1431,33 @@ func (a *Api) JoinGroupByInviteLink(c *gin.Context) {
 	c.Status(http.StatusNoContent)
 }
 
+// @Summary Get a Signal Group info by invite link.
+// @Tags Groups
+// @Description Get the specified Signal Group info by invite link.
+// @Accept  json
+// @Produce  json
+// @Success 200 {string} OK
+// @Failure 400 {object} Error
+// @Param number path string true "Registered Phone Number"
+// @Query invite_link query string true "Invite Link"
+// @Router /v1/groups/{number}/join_info_by_invite_link [get]
+func (a *Api) GetJoinGroupInfoByInviteLink(c *gin.Context) {
+	number := c.Param("number")
+	if number == "" {
+		c.JSON(400, Error{Msg: "Couldn't process request - number missing"})
+		return
+	}
+
+	inviteLink := c.Query("invite_link")
+	jsonStr, err := a.signalClient.GetJoinGroupInfoByInviteLink(number, inviteLink)
+	if err != nil {
+		c.JSON(400, Error{Msg: err.Error()})
+		return
+	}
+
+	c.String(200, jsonStr)
+}
+
 // @Summary Quit a Signal Group.
 // @Tags Groups
 // @Description Quit the specified Signal Group.

src/client/client.go

@@ -1578,6 +1578,14 @@ func (s *SignalClient) JoinGroupByInviteLink(number string, inviteLink string) e
 	return err
 }
 
+func (s *SignalClient) GetJoinGroupInfoByInviteLink(number string, inviteLink string) (string, error) {
+	if s.signalCliMode == JsonRpc {
+		return "", errors.New("Not implemented")
+	}
+
+	return s.cliClient.Execute(true, []string{"--config", s.signalCliConfig, "--output", "json", "-a", number, "getJoinGroupInfo", "--uri", inviteLink}, "")
+}
+
 func (s *SignalClient) QuitGroup(number string, groupId string) error {
 	var err error
 	if s.signalCliMode == JsonRpc {

src/main.go

@@ -195,6 +195,7 @@ func main() {
 			groups.POST(":number", api.CreateGroup)
 			groups.GET(":number", api.GetGroups)
 			groups.POST(":number/join_by_invite_link", api.JoinGroupByInviteLink)
+			groups.GET(":number/join_info_by_invite_link", api.GetJoinGroupInfoByInviteLink)
 			groups.GET(":number/:groupid", api.GetGroup)
 			groups.DELETE(":number/:groupid", api.DeleteGroup)
 			groups.POST(":number/:groupid/block", api.BlockGroup)