小编Dan*_*Dan的帖子

我正在自学C.我的目标是创建一个C函数,它只是遍历一个查询字符串并在&符号和等号上分开.我对Valgrind的这个错误感到困惑.

==5411== Invalid free() / delete / delete[] / realloc()
==5411==    at 0x402AC38: free (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==5411==    by 0x804857C: main (leak.c:28)
==5411==  Address 0x420a02a is 2 bytes inside a block of size 8 free'd
==5411==    at 0x402AC38: free (in /usr/lib/valgrind/vgpreload_memcheck-x86-linux.so)
==5411==    by 0x804857C: main (leak.c:28)
==5411== 
==5411== 
==5411== HEAP SUMMARY:
==5411==     in use at exit: 0 bytes in 0 blocks
==5411==   total heap usage: 1 allocs, 2 frees, 8 bytes allocated
==5411== 
==5411== All heap blocks were freed -- no …

我从17.10升级到ubuntu 18.04.无法完全安装redis-server软件包.我看了/ var/log/syslog,它说

==> /var/log/syslog <==
Jun  3 13:04:10 qaz-mko systemd[1]: redis-server.service: Can't open PID file /var/run/redis/redis-server.pid (yet?) after start: No such file or directory
Jun  3 13:05:01 qaz-mko CRON[3429]: (root) CMD (command -v debian-sa1 > /dev/null && debian-sa1 1 1)
Jun  3 13:05:40 qaz-mko systemd[1]: redis-server.service: Start operation timed out. Terminating.
Jun  3 13:05:40 qaz-mko systemd[1]: redis-server.service: Failed with result 'timeout'.
Jun  3 13:05:40 qaz-mko systemd[1]: Failed to start Advanced key-value store.
Jun  3 13:05:40 qaz-mko systemd[1]: redis-server.service: Service …

我正在使用此函数解压缩正文或HTTP响应（如果使用gzip对其进行了压缩，压缩或放气）。

def uncompress_body(self, compression_type, body):
    if compression_type == 'gzip' or compression_type == 'compress':
        return zlib.decompress(body)
    elif compression_type == 'deflate':
        compressor = zlib.compressobj(9, zlib.DEFLATED, -zlib.MAX_WBITS)
        compressed = compressor.compress(body)
        compressed += compressor.flush()
        return base64.b64encode(compressed)

    return body

但是python抛出此错误消息。

TypeError: a bytes-like object is required, not '_io.BytesIO'

在这条线上：

return zlib.decompress(body)

本质上，我如何从“ _io.BytesIO”转换为类似字节的对象？

谢谢

我如何在 postgresql 函数中实现按列和排序方向的动态排序。

这是我到目前为止所拥有的：

CREATE OR REPLACE FUNCTION get_urls_by_crawl_id(
    p_account_id character varying(64),
    p_crawl_id character varying(64),
    p_sort_column character varying(30),
    p_sort_direction character varying(30),
    p_page integer,
    p_total integer
)
RETURNS TABLE(id character varying(64), source_url text, http_status_code integer, ref_cnt integer) AS $BODY$
BEGIN
    RETURN QUERY SELECT u.id, u.source_url, u.http_status_code, u.ref_cnt FROM url AS u 
    JOIN crawl AS c ON(u.crawl_id = c.id) 
    JOIN site AS s ON(c.site_id = s.id)
    JOIN person AS p ON(s.person_id = p.id)
    WHERE p.account_id = p_account_id AND u.crawl_id = p_crawl_id AND …

是否可以获取使用 aiohttp 发出的每个请求的响应时间和响应大小？

文档似乎在任何地方都没有这些属性。

谢谢

到目前为止我有这样的事情：

page_nr = request.query.page_nr
how_many = request.query.how_many
sort_direction = request.query.sort_direction
sort_column = request.query.sort_column

error_urls = Url.select().where((Url.crawl == crawl_id)) \
            .order_by(Url.total_time.desc()) \
            .paginate(int(page_nr), int(how_many)) \
            .dicts()

如您所见，我没有使用 sort_direction 和 sort_column。我尝试了下面的查询，但没有成功。

error_urls = Url.select().where((Url.crawl == crawl_id) & (Url.utype == 'internal')) \
            .order_by(SQL(sort_column).sort_direction()) \
            .paginate(int(page_nr), int(how_many)) \
            .dicts()

(500, 'Internal Server Error', AttributeError("'SQL' object has no attribute 'sort_direction'",), 'Traceback (most recent call last):\n  File "/usr/local/lib/python3.5/dist-packages/bottle.py", line 862, in _handle\n    return route.call(**args)\n  File "/usr/local/lib/python3.5/dist-packages/bottle.py", line 1732, in wrapper\n    rv = callback(*a, **ka)\n  File "index.py", …

什么是 Powershell cmd: findstr 的“上下文行控制”设置，或者什么是替代 Powershell cmd，它可以让我在某些输出中找到一个字符串，还可以方便地打印周围的行？

在 GNU/Linux 上，我会这样做： grep -A 5 -B 5 somestring file.txt

下面的命令搜索字符串“four”，但要求 grep 在找到的行上方显示 1 行，在找到的包含字符串的行下方显示 2 行。

$ grep -A 2 -B 1 four tmp.text
three
four
five
six
$ cat tmp.text
one
two
three
four
five
six
seven

谢谢

这是我的 SourceRepository 类，它不会覆盖自动生成的通用 findAll() ，它返回 Iterable

package com.infostream.repositories;

import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.repository.PagingAndSortingRepository;

import com.infostream.models.Source;

public interface SourceRepositoryImpl extends PagingAndSortingRepository<Source, Long>{

    Page<Source> findAll(Pageable pageRequest);

}

这是我的服务类别：

package com.infostream.services;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageImpl;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Component;

import com.infostream.models.Source;
import com.infostream.repositories.SourceRepositoryImpl;

@Component
public class SourcesService {
    @Autowired
    private SourceRepositoryImpl sourceRepository;

    public PageImpl<Source> getPaginatedSources(Pageable pageRequest) {
        Page<Source> searchResultPage = sourceRepository.findAll(pageRequest);
        return new PageImpl<Source>(searchResultPage.getContent(), pageRequest, searchResultPage.getTotalElements()); 
    }

    public Iterable<Source> getAllSources() {
        return sourceRepository.findAll();
    }
}

这是我作为 Java 应用程序运行的主类。

package com.infostream.services; …