无法将bson类型的字符串转换为日期

Question

我正在尝试执行此mongodb查询：

int get_next_line(int fd, char **line)
{
    char *buff;
    int bwr;
    char *ptr;
    int bol;
    static char *rem;


    bol = 1; 
    buff = (char *)malloc(sizeof(char) * (BUFFER_SIZE + 1));
    if(rem)
    {
        *line = ft_strdup(rem);
        printf("---1ST---%s\n", rem);
        free(rem);
        printf("---2ND---%s\n", rem);
    }
    else
        *line = ft_strdup("");
    while (bol && (bwr = read(fd, buff, BUFFER_SIZE)))
    {
        buff[bwr] = '\0';
        if ((ptr = ft_strchr(buff, '\n')))
        {
            rem = ft_strdup(ptr + 1);
            *ptr = '\0'; 
            bol = 0;
        }
        *line = ft_strjoin(*line ,buff);
    }
        return(0);
}

但是我遇到了这个错误：

db.getCollection('collection').aggregate([
     {$project: {yearMonthDay: { $dateToString: { format: "%Y-%m-%d", date: "$date" } }}}, 

    {$match: { yearMonthDay: { $eq: "2018-03-02" } }}
 ]).count()