资讯专栏INFORMATION COLUMN

开发错误集锦

awesome23 / 3783人阅读

摘要:加了代理,而对这个配置默认执行操作,导致了连接错误。失败的执行时候会报错这是因为通过调用自身的方法,使用根据主键去重复的逻辑覆盖了的逻辑。

emoji

utf8 编码问题 https://laravel-china.org/top...

  function nickname_encode($s){
        $chars = preg_split("//u", $s, null, PREG_SPLIT_NO_EMPTY);
        foreach ($chars as &$c) {
            if (strlen($c) > 3 || $c === "%"){
                $c = urlencode($c);
            }
        }

        return implode($chars);
    }
解码直接用urldecode就行了。
strtotime
var_dump(date("Y-m-d", strtotime("2017-06-31")));
//输出2017-07-01
var_dump(date("Y-m-d", strtotime("-1 month", strtotime("2017-03-31"))));
//输出2017-03-03
var_dump(date("Y-m-d", strtotime("+1 month", strtotime("2017-08-31"))));
//输出2017-10-01
var_dump(date("Y-m-d", strtotime("next month", strtotime("2017-01-31"))));
//输出2017-03-03
var_dump(date("Y-m-d", strtotime("last month", strtotime("2017-03-31"))));
//输出2017-03-03

var_dump(date("Y-m-d", strtotime("last day of -1 month", strtotime("2017-03-31"))));
//输出2017-02-28
var_dump(date("Y-m-d", strtotime("first day of +1 month", strtotime("2017-08-31"))));
////输出2017-09-01
var_dump(date("Y-m-d", strtotime("first day of next month", strtotime("2017-01-31"))));
////输出2017-02-01
var_dump(date("Y-m-d", strtotime("last day of last month", strtotime("2017-03-31"))));
////输出2017-02-28

需要获得多少天之前 $day 

mktime(0, 0, 0, date("m", $startTime), date("d", $startTime) - $day, date("Y", $startTime));

 这个坑在carbon中一样的有. 比如:Carbon::now()->subMonth(1)->startOfMonth() 一样的会出现上面说的问题. 你必须这样写:Carbon::now()->startOfMonth()->subMonth(1)
 Carbon::now()->subMonthNoOverflow(1)->startOfMonth()
https://laravel-china.org/articles/17317

$i = 12;

while($i >= 1) {
    echo date("Y-m", strtotime("-" . $i . " month", strtotime("2018-8"))) . "
";
    $i--;
}

https://laravel-china.org/art...
解决方法

??
运算符可 用于判断$a变量不存在的情况(也可用于数组),而使用三元运算符判断一个未定义的变量,PHP会抛出异常。也正是因为这样,用??判断一个赋值为0的变量的时候结果是不一样的。https://laravel-china.org/articles/17304?#reply64712
$a=0;
$c=1;
$b=$a??$c;
echo "a:".$a.",b:".$b.",c:".$c;
//a:0,b:0,c:1
$a=0;
$c=1;
$b=$a?$a:$c;
echo "a:".$a.",b:".$b.",c:".$c;
//a:0,b:1,c:1
Error while reading line from the server. [tcp://127.0.0.1:6379]

redis 加了代理 Twemproxy,而 predis 对这个配置默认执行 select 操作,导致了连接错误。

大家以后要注意,如果 redis 有代理的话,别忘了把 "database" => 0,这个配置删掉。
https://laravel-china.org/top...

PHP empty 函数判断结果为空
class person
{
    protected $attributes = [];

    public function __construct(array $attributes)
    {
        $this->attributes = $attributes;
    }

    public function __get($name)
    {
        return $this->attributes[$name] ?? null;
    }
}
https://laravel-china.org/articles/12530/the-shock-php-empty-function-is-empty-but-the-actual-value-is-nonempty

https://laravel-china.org/topics/3021/isset-is-not-right-after-upgrading-php7
var_dump(
    $person->firstName,
    empty($person->firstName),
    isset($person->firstName),
    is_null($person->firstName)
);
Laravel Redis 多个进程同时取队列问题

Laravel 使用 Redis 的 list 作为队列的数据结构,并会为每个队列分配一个 ID
Laravel 中入队列方法

 
public function pushRaw($payload, $queue = null, array $options = [])
{
 $this->getConnection()->rpush($this->getQueue($queue), $payload);
  
 return Arr::get(json_decode($payload, true), "id");
}
用的是 Redis 的 rpush 命令。

Laravel 中取队列方法
 
public function pop($queue = null)
{
 $original = $queue ?: $this->default; 
 $queue = $this->getQueue($queue); 
 $this->migrateExpiredJobs($queue.":delayed", $queue); 
 if (! is_null($this->expire)) {
  $this->migrateExpiredJobs($queue.":reserved", $queue);
 } 
 list($job, $reserved) = $this->getConnection()->eval(
  LuaScripts::pop(), 2, $queue, $queue.":reserved", $this->getTime() + $this->expire
 ); 
 if ($reserved) {
  return new RedisJob($this->container, $this, $job, $reserved, $original);
 }
}
这里用的是 lua 脚本取队列,如下:

 
public static function pop()
{
 return <<<"LUA"
local job = redis.call("lpop", KEYS[1])
local reserved = false
if(job ~= false) then
reserved = cjson.decode(job)
reserved["attempts"] = reserved["attempts"] + 1
reserved = cjson.encode(reserved)
redis.call("zadd", KEYS[2], ARGV[1], reserved)
end
return {job, reserved}
LUA;
}

那么结论是:从 Laravel 的处理方式和打印的日志结果看,即使多个进程读取同一个队列,也不会读取到一样的数据。

队列执行失败之后根本不会执行failed方法

执行队列侦听器时加上 --tries参数即可,failed()方法只有在重试指定次数完成后才会调用failed()方法如:
http://blog.zhouchenxi.cn/pos...
php artisan queue:listen --queue=default,listeners --tries=3
顺便提一下:如果指定了队列名称必须在侦听器的参数上加上 --queue参数才行,不然没有指定的队列是不会运行的。
event 指定队列

  public $queue = "listeners";
public function queue($queue, $job, $data)
       {
              if (isset($this->queue, $this->delay)) {
                     return $queue->laterOn($this->queue, $this->delay, $job, $data);
              }

              if (isset($this->queue)) {
                     return $queue->pushOn($this->queue, $job, $data);
              }

              if (isset($this->delay)) {
                     return $queue->later($this->delay, $job, $data);
              }

              return $queue->push($job, $data);
       }
php7不支持 preg_replace e修正符

车轮升级PHP7踩过的一些坑 http://php.swoole.com/wiki/%E...

php5 php7不兼容的地方:https://segmentfault.com/a/11...

$joinStr = preg_replace("/__([A-Z_-]+)__/e",$prex.".strtolower("$1")",$joinStr);
//替换为
preg_replace_callback("/__([A-Z_-]+)__/",function($r) use (&$joinStr){
    $joinStr = $prex.strtolower($r[1]);
},$joinStr);
内存溢出
//https://laravel-china.org/articles/16312/handling-large-amounts-of-data-to-write-files-to-avoid-memory-overflow-and-response-timeout
$beginIndex = 0;
    $pageLimit = 50000;
    $endIndex = $beginIndex + $pageLimit;

    while ($pageData = DB::connection("hub_log")->select("SELECT * FROM `{$tableName}` WHERE id > {$beginIndex} and id <= {$endIndex}")) {

        foreach ($pageData as $row) {
            file_put_contents(storage_path("mcd_rawdata/".$tableName.".txt"), $row->Content . "
", FILE_APPEND);
        }

        $beginIndex += $pageLimit;
        $endIndex += $pageLimit;
    }
    
    $public_path = $time."test.txt";

    DB::table("20171220")->orderBy("id")->chunk(10000,function($data) use ($public_path){
        $arr = "";
        foreach ($data->toArray() as $key => $value) {
            $arr .= $value->Content."
";
        }

        file_put_contents(public_path($public_path),$arr, FILE_APPEND);
        unset($data);unset($arr);
    });
git bash 输入python命令停滞

$ python -i
$ winpty python -3

保留两位小数

round(a,2)
r = lambda f: f - f % 0.01
int(a*100)/100
print("%.2f" %a)

后期绑定

https://www.v2ex.com/t/482659...

def testFun():
    return(lambda x : i*x for i in range(4))
for everyLambda in testFun():
    print(everyLambda(2))
& python test.py
0
2
4
6
def testFun():
    temp = [lambda x : i*x for i in range(4)]
    return temp
for everyLambda in testFun():
    print(everyLambda(2))
& python test.py
6
6
6
6
第一个是括号(), 为生成器, 返回 generator
第二个是中括号[], 为列表生成式, 返回数组 列表表达式是即时计算的, 而生成器是迭代时才会计算
{} + []
({}).valueOf() // []
// 返回来的是个对象,继续调用 toString https://www.v2ex.com/t/480998#reply11
[].toString() // ""

[] + 1// "1"
[] + "a" // "a"
echo 后发送 header

使用 fastcgi_finish_request();( PHP-fpm )可以强制断开客户端连接 session 本质上是 header set-cookie,所以不算输出。这里的输出指的是 response body 的部分
https://www.v2ex.com/t/481127...

isset在php5.6-和php7.0+的一些差异
https://segmentfault.com/a/1190000016097997
class ProductCategory
{
    const TYPES = [
        1 => "type1",
        2 => "type2",  
    ];
    
    public function getType()
    {
        return isset(self::TYPES[$this->type]) ? self:TYPES[$this->type] : "unrecognized_type";
    }
}
//把汉字拆分为数组
function ch2arr($str)
{
    return preg_split("//u", $str, null, PREG_SPLIT_NO_EMPTY);
}
laravel 中使用 导出 excel 时报错

PHPExcel_Calculation_Exception: Q5!A65 → Formula Error: An unexpected error occured in /application/www/web_git-pull/vendor/phpoffice/phpexcel/Classes/PHPExcel/Cell.php:291

原因:

在excel中一个单元格如果是以=开头,则说明这个单元格是根据其他单元格的值算出来的,=后面必须跟着一个合法的表达式,而那个字符串是用户的输入,很明显不应该是一个合法的表达式,所以应该在代码中过滤掉

解决:
$str = " ".$str;//同时解决 如 11111111111 显示成 1.11111E+29
参考
https://github.com/Maatwebsit...
https://stackoverflow.com/que...

gzip UnicodeDecodeError

gzip解码问题

import urllib.request
import gzip

# 注意要先读取内容才可以解压缩
data = urllib.request.urlopen(url).read()
try:
    html =data.decode("utf-8")
except:
    html =gzip.decompress(data).decode("utf-8")
Intervention/Image 图片写入中文
https://laravel-china.org/topics/13642/problems-encountered-in-writing-chinese-with-interventionimage-pictures-and-solutions
function to_unicode($string)
{
    $str = mb_convert_encoding($string, "UCS-2", "UTF-8");
    $arrstr = str_split($str, 2);
    $unistr = "";
    foreach ($arrstr as $n) {
        $dec = hexdec(bin2hex($n));
        $unistr .= "&#" . $dec . ";";
    }
    return $unistr;
}
获取某字段修改前的值
Issue::saving(function(Issue $issue){
    if ($issue->isDirty("title")) {
        $user = Auth::user()->username;
        $oldTitle = $issue->getOriginal("title"); // 原始值
        $newTitle = $issue->title;                // 新值
        ActionLog::log("$user 把标题 $oldTitle 修改为 $newTitle");
    }
});
前一天
https://www.cnblogs.com/lhm166/articles/6066762.html
$mytime=mktime(0, 0, 0, date("m"), date("d")-1, date("Y"));//获取时间戳
$mytime=date("Y-m-d H:i:s", strtotime("-1 day")); //获取格式为2016-12-30 13:26:13
$timetoday = strtotime(date("Y-m-d",time()));
function mdate($time = NULL) {
    $text = "";
    $time = $time === NULL || $time > time() ? time() : intval($time);
    $t = time() - $time; //时间差 (秒)
    $y = date("Y", $time)-date("Y", time());//是否跨年
    switch($t){
     case $t == 0:
       $text = "刚刚";
       break;
     case $t < 60:
      $text = $t . "秒前"; // 一分钟内
      break;
     case $t < 60 * 60:
      $text = floor($t / 60) . "分钟前"; //一小时内
      break;
     case $t < 60 * 60 * 24:
      $text = floor($t / (60 * 60)) . "小时前"; // 一天内
      break;
     case $t < 60 * 60 * 24 * 3:
      $text = floor($time/(60*60*24)) ==1 ?"昨天 " . date("H:i", $time) : "前天 " . date("H:i", $time) ; //昨天和前天
      break;
     case $t < 60 * 60 * 24 * 30:
      $text = date("m月d日 H:i", $time); //一个月内
      break;
     case $t < 60 * 60 * 24 * 365&&$y==0:
      $text = date("m月d日", $time); //一年内
      break;
     default:
      $text = date("Y年m月d日", $time); //一年以前
      break;
    }
        
    return $text;
}function friend_date($time)
{
    if (!$time)
        return false;
    $fdate = "";
    $d = time() - intval($time);
    $ld = $time - mktime(0, 0, 0, 0, 0, date("Y")); //得出年
    $md = $time - mktime(0, 0, 0, date("m"), 0, date("Y")); //得出月
    $byd = $time - mktime(0, 0, 0, date("m"), date("d") - 2, date("Y")); //前天
    $yd = $time - mktime(0, 0, 0, date("m"), date("d") - 1, date("Y")); //昨天
    $dd = $time - mktime(0, 0, 0, date("m"), date("d"), date("Y")); //今天
    $td = $time - mktime(0, 0, 0, date("m"), date("d") + 1, date("Y")); //明天
    $atd = $time - mktime(0, 0, 0, date("m"), date("d") + 2, date("Y")); //后天
    if ($d == 0) {
        $fdate = "刚刚";
    } else {
        switch ($d) {
            case $d < $atd:
                $fdate = date("Y年m月d日", $time);
                break;
            case $d < $td:
                $fdate = "后天" . date("H:i", $time);
                break;
            case $d < 0:
                $fdate = "明天" . date("H:i", $time);
                break;
            case $d < 60:
                $fdate = $d . "秒前";
                break;
            case $d < 3600:
                $fdate = floor($d / 60) . "分钟前";
                break;
            case $d < $dd:
                $fdate = floor($d / 3600) . "小时前";
                break;
            case $d < $yd:
                $fdate = "昨天" . date("H:i", $time);
                break;
            case $d < $byd:
                $fdate = "前天" . date("H:i", $time);
                break;
            case $d < $md:
                $fdate = date("m月d日 H:i", $time);
                break;
            case $d < $ld:
                $fdate = date("m月d日", $time);
                break;
            default:
                $fdate = date("Y年m月d日", $time);
                break;
        }
    }
    return $fdate;
}
phpstorm xdebug

https://www.cnblogs.com/baoch...
https://www.cnblogs.com/niuxi...
https://laravel-china.org/top...
https://laravel-china.org/art...
https://laravel-china.org/art...

如果出现Can"t start listening for connections from "xdebug": Port 9000 is busy
可修改端口号,要修改两个地方
第一个地方是刚才php.ini里面的xdebug.remote_port=9000
第二个地方是phpstorm - setting - Languages&Frameworks - 相应的语言(比如PHP) - debug - 修改里面的Debug port
Python for 循环中的陷阱

https://www.v2ex.com/t/470443...

pyinstaller 打包 exe

pyinstaller -p venv_path (中间一定要有空格) you.py https://www.v2ex.com/t/476247...
http://ju.outofmemory.cn/entr...

php捕获fatal error
function fatal_handler() {
    $errfile = "unknown file";
    $errstr  = "shutdown";
    $errno   = E_CORE_ERROR;
    $errline = 0;
    $error = error_get_last();
    if($error){
      //发送邮件队列也可以http://www.iamtb.cn/2017/11/17/php-catch-fatel-error/
        file_put_contents("./testerror11.txt", json_encode($error));
    }
}
register_shutdown_function("fatal_handler");
try{
    $db=new db();
}catch(Exception $e){
echo $e->error_msg();
}
PHP7开始,含十六进制字符串不再被认为是数字
$str = "0xffff";//https://segmentfault.com/q/1010000004829059
$int = filter_var($str, FILTER_VALIDATE_INT, FILTER_FLAG_ALLOW_HEX);
if (false === $int) {
    throw new Exception("Invalid integer!");
}
var_dump($int); // int(65535)
$t1 = 0x3FFFFFFF & (1 * (0xd5b42e11));
$t2 = 0x3FFFFFFF & (1 * (filter_var("0xd5b42e11", FILTER_VALIDATE_INT, FILTER_FLAG_ALLOW_HEX)));

var_dump($t1,$t2);
php artisan config:cache

cat config/sentry.php
return array(
    "dsn" => env("SENTRY_LARAVEL_DSN"),

    // capture release as git sha
    // "release" => trim(exec("git log --pretty="%h" -n1 HEAD")),

    // Capture bindings on SQL queries
    "breadcrumbs.sql_bindings" => true,

    // Capture default user context
    "user_context" => false,

    //transport function
    "transport"=>function(Raven_Client $raven_Client,&$data){
        $raven_Client->setTransport(null);
          $raven_Client->close_curl_resource();
            Queue::pushOn("sentry",new AppCommandssentry($raven_Client,$data));
        },
);

"transport"=>new appSentryTransport(),
class SentryTransport
{
    public static function __set_state($arr){
        return function($raven_Client,&$data){
            Queue::pushOn("sentry",new AppCommandssentry($raven_Client,$data));
        };
    }
}
curl超时
//重试
$ch = curl_init();
// curl_setopt ($ch, CURLOPT_URL, "produc_redis.php.com");
curl_setopt ($ch, CURLOPT_URL, "11.11.11.1");

https://segmentfault.com/a/1190000011188541
// I changed UA here
curl_setopt ($ch, CURLOPT_USERAGENT, "Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.1) Gecko/20061204 Firefox/2.0.0.1");

curl_setopt ($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt ($ch, CURLOPT_CONNECTTIMEOUT, 2);
curl_setopt ($ch, CURLOPT_AUTOREFERER, true);
curl_setopt ($ch, CURLOPT_SSL_VERIFYPEER, false);
curl_setopt ($ch, CURLOPT_SSL_VERIFYHOST, 2);

$html = curl_exec($ch);

var_dump($html,curl_error($ch));

$num=3;
for($i=1;$i<=$num;$i++){
    if(curl_getinfo($ch,CURLINFO_HTTP_CODE)=="0" && $i<=$num){
      echo "retry $i 次".PHP_EOL;
      if($i==3){
          curl_setopt ($ch, CURLOPT_URL, "220.181.57.217");
      }
      $html = curl_exec($ch);
 }
}

var_dump($html);

var_dump(curl_error($ch));

// var_dump(curl_getinfo($ch));

/**
 * curl请求
 *https://segmentfault.com/a/1190000010197068
 * @param $url
 * @param string $postData
 * @param int $timeout
 * @return array|mixed
 * @throws Exception
 */
protected static function post($url, $postData = "", $timeout = 5)
{
    $ret = array();
    $times = 5;
    do {
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_HEADER, false);
        if ($postData != "") {
            curl_setopt($ch, CURLOPT_POSTFIELDS, $postData);
        }
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, $timeout);
        // 重要, 该处不能丢 curl 执行最大秒数
        curl_setopt($ch, CURLOPT_TIMEOUT, $timeout);
        $output = curl_exec($ch);
        if ($errNo = curl_errno($ch)) {
            error_log("Error [$errNo]: " . curl_error($ch));
        } else {
            $ret = json_decode($output, true);
            // 解析的结果集为空时停止查询
            if (!is_array($ret) && !trim($ret)) {
                throw new Exception(__METHOD__ . ": cURL调用失败, 信息为: " . $output);
            }
            unset($output);
        }
        curl_close($ch);
        if (isset($ret[0]) && $ret[0]) {
            return $ret;
        }
    } while ($times--);
    exit(__METHOD__ . ": cURL请求重试至 {$times} 次后仍无响应, 执行退出");
}
cURL error 28
cURL error 28: See http://curl.haxx.se/libcurl/c/libcurl-errors.html
$client=new GuzzleHttpClient();
try {
    $tmp = $client->get($url,array("timeout"=>3,"connect_timeout"=>3));
    $res = json_decode(strval($tmp->getBody()),1);
} catch (Exception $e) {
    $res = [];
    Log::info("error", ["url" => $url, "msg" => $e->getMessage()]);
}
$client=new GuzzleHttpClient();
        $requests=[
            $client->createRequest("GET",$url,["timeout"=>3,"connect_timeout"=>3]),
            $client->createRequest("GET",$url2,["timeout"=>3,"connect_timeout"=>3]),
            
        ];
$result = Pool::batch($client, $requests, ["pool_size" => 2]);
//$result->getResult($requests[0]) instanceof GuzzleHttpMessageResponse
if ($result[0] instanceof Response && $result[0]->getStatusCode() == 200) {
            $data = json_decode($result[0]->getBody(), true);
  }
格式化
import prettytable as pt
https://www.v2ex.com/t/483984#reply15
## 按行添加数据
tb = pt.PrettyTable()
tb.field_names = ["City name", "Area", "Population", "Annual Rainfall"]
tb.add_row(["Adelaide",1295, 1158259, 600.5])
tb.add_row(["Brisbane",5905, 1857594, 1146.4])
tb.add_row(["Darwin", 112, 120900, 1714.7])
tb.add_row(["Hobart", 1357, 205556,619.5])

print(tb)
 #str.ljust 和 rjust 才是王道,谁用谁知道!

+-----------+------+------------+-----------------+
| City name | Area | Population | Annual Rainfall |
+-----------+------+------------+-----------------+
| Adelaide | 1295 | 1158259 | 600.5 |
| Brisbane | 5905 | 1857594 | 1146.4 |
| Darwin | 112 | 120900 | 1714.7 |
| Hobart | 1357 | 205556 | 619.5 |
+-----------+------+------------+-----------------+
unicode

Unicode 每个字符的详情,可以查官方文档: https://www.unicode.org/charts/
python2 代码:

for i in range(0x005b,0x005f):
print (unichr(i))#print (chr(i))
python3 代码请查看 http://www.chenxm.cc/post/683...
unicode 字符表示方法 u + 16 进制数值,例如 u0001 print("".join(chr(u) for u in range(0, 0x41))) u0040 这里 0040 就是 16 进制的,range 是左闭右开的,所以u0020-u0040 的码点范围是 range(0x00, 0x40+1)
0b 二进制 0o 八进制 0x 16 进制
0b10 // 2
0o10 // 8
0x10 // 16
unicode 字符表示方法 u + 16 进制数值,例如 u0001
print(u"u0061") // ahttps://www.v2ex.com/t/484923...

laravel更新后读取数据失败
https://laravel-china.org/articles/16566/take-a-laravel-mysql-to-verify-the-experience-of-bug#reply62596
//创建数据
$meeting = meeting::create($data);

//查询数据
$meeting = meeting::findOrFail($meeting->id);

//纪录操作日志
Log::insert($meeting);
线上数据库是读写分离的,主库写入,但更新数据后马上查询,从库可能没来得及更新数据
当网络不好时遇到从库更新不及时 findOrFail 就会报 404,导致后面所有操作都失效,自然验证也失效了
解决方法

更新完后,查询指定使用主库
更新后禁止查询,直接使用 create 返回的 model 实例,对于数据库中的有默认值的字段,手动加入到 model 实例中
批量更新
//https://laravel-china.org/topics/6864/how-to-batch-update-accumulate-a-field
https://laravel-china.org/articles/16620/laravel-project-execl-batch-import-database-data-update-data-no-insertion
$arr = [
// user_id => reward
  "1" => 50,
  "2" => 30,
  "3" => 60
];
User::find(array_keys($arr))->each(function ($query) use ($arr) {
  $query->increment("award" , $arr[$query->id]);
});
# 批量更新相同的 award
User::find(array_keys($arr))->each->increment("award", 30);

/**
         * 批量更新表的值,防止阻塞
         * @note 生成的SQL语句如下:
         * update mj_node set sort = case id
         *      when 13 then 1
         *      when 1 then 4
         *      when 7 then 5
         *      when 8 then 6
         *      when 9 then 7
         *      when 10 then 8
         *      when 11 then 9
         *      when 12 then 10
         * end where id in (13,1,7,8,9,10,11,12)
         * @param $conditions_field 条件字段
         * @param $values_field  需要被更新的字段
         * @param $conditions
         * @param $values
         * @return int
         */
        public function batchUpdate($conditions_field, $values_field, $conditions, $values)
        {
                $table = $this->model->getFullTableName();//返回完整表名,自己在项目中定义
                $sql   = "update " . $table . " set ". $values_field ." = case " .$conditions_field;
                foreach ($conditions as $key => $condition) {
                        $sql .= " when " . $condition . " then ?";
                }
                $sql .= " end where id in (" . implode(",", $conditions) . ")";
                return DB::update($sql, $values);//项目中需要引入DB  facade
        }
cat 多换行
https://www.v2ex.com/t/188162
调试shell脚本可以使用 sh -x ****.sh,有详细输出内容
Bash的echo默认在末尾加了换行符"
",所以你cat那个文件多了一个换行符,给echo加上-n参数就能不自动加换行符了。

var= cat tmp.txt;echo $var"abc" 改成如下的形式

var= `cat tmp.txt`;echo $var"abc"或者 #注意不是单引号,是tab键上面1前面的那个符号
var=$(cat tmp.txt);echo $var"abc"
grep and or
https://blog.csdn.net/jackaduma/article/details/6900242
grep -E "Tech|Sales" employee.txt
grep -v "pattern1" filename
$ grep -E "Manager.*Sales|Sales.*Manager" employee.txt  # -E "pattern1.*pattern2"
egrep "php.*artisan.*$1"
egrep "pattern1|pattern2" filename
memcached 默认的过期时间则 不能大于 30 天

https://laravel-china.org/top...

cron 内容最后一行未回车

https://segmentfault.com/a/11... crontab -u www -e

unix:///tmp/supervisor.sock refused connection
[root@localhost supervisor]# supervisorctl -c /etc/supervisord.conf
unix:///tmp/supervisor.sock refused connection
supervisor> exit
 rm -f /tmp/supervisor.sock
[root@localhost supervisor]# ps aux|grep super
root        48  0.0  0.0      0     0 ?        S     2017   2:17 [sync_supers]
root      8246  0.0  0.1 208064 13404 ?        Ss   18:17   0:00 /usr/bin/python /usr/bin/supervisord -c /etc/supervisord.conf
supervisord是服务端,是个deamon,supervisorctl是客户https://www.v2ex.com/t/210122
修改supervisor.conf文件后,要执行supervisorctl reload,重新加载配置文件
vi artisan.conf
[root@localhost supervisor]# supervisorctl status
unix:///tmp/supervisor.sock no such file
[root@localhost supervisor]# ps aux|grep super
root        48  0.0  0.0      0     0 ?        S     2017   2:17 [sync_supers]
root     19472  0.0  0.0 103256   844 pts/5    S+   19:57   0:00 grep super
[root@localhost supervisor]# supervisord -c /etc/supervisord.conf
Error: Invalid user name www in section "program:artisan_queue" (file: "/etc/supervisor/artisan.conf")
For help, use /usr/bin/supervisord -h
[root@localhost supervisor]# vi /etc/supervisor/artisan.conf
[root@localhost supervisor]# supervisord -c /etc/supervisord.conf
[root@localhost supervisor]# supervisorctl status
artisan_queue                    BACKOFF   Exited too quickly (process log may have details)

http://blog.51cto.com/jxlwc/2112062 
https://www.jianshu.com/p/3658c963d28b
Specified key was too long
https://laravel-china.org/articles/17094/larave-admin-installation?#reply64528
默认的数据库字符集,现在utf8mb4包括存储emojis支持。如果你运行MySQL v5.7.7或者更高版本,则不需要做任何事情。
https://laravel-china.org/articles/4195/laravel-54-common-error-specified-key-was-too-long
https://segmentfault.com/a/1190000008416200
把config下的database.php下的mysql设置中,将"strict" => false就行了..
Schema::defaultStringLength(191); 是设置好的默认的字符串长度,也就是说,迁移中的字段没有设置长度的话,varchar 字段会被默认成长度只有 191
use IlluminateSupportFacadesSchema;

public function boot()
{
    Schema::defaultStringLength(191);
}
laravel with 查询中只查询个别字段
select 的时候没有 id 的话就会为 null https://laravel-china.org/articles/17379
public function brand()
 {
        return $this->belongsTo(Brand::class, "brandId")->select("id", "briefCode");
 }
 $result = Brand::with(["brand" =>  function($query){
    $query->select("id", "briefCode");
}])->get();
PHP输出A到Z
for($i="A"; $i<="Z"; $i++)
{
    echo $i . "
"; } for($i=ord("A"); $i<=ord("Z"); $i++) { echo chr($i) . "
"; } for($i = "A"; $i != "BB"; $i++) { echo $i . "
"; } $al = "A"; while($al != "BB") { echo $al++ . "
"; }
env函数的小坑
dump(env("APP_ENV") === null); // true 
因为没有执行 config:cache 命令,而项目上线后为了优化访问速度,生成了缓存文件,导致env取值失败
如果使用了config:cache,env函数只能在config目录下的配置文件的php里使用,不可以在其他地方使用。

一个非常简单的办法就是将
env("APP_ENV")改为config("app.env")
config函数会优先读取 bootstrap/cache/config.php 中缓存的配置,如果没有缓存文件,则会直接读取 config 目录下的所有配置文件
https://www.jianshu.com/p/83f9cd407751
任务调度的列表
//1. 加载Console内核
app()->make(IlluminateContractsConsoleKernel::class);

//2.  获取计划任务列表
$scheduleList = app()->make(IlluminateConsoleSchedulingSchedule::class)->events();
在模型事件中获取某字段修改前的值
Issue::saving(function(Issue $issue){
    if ($issue->isDirty("title")) {
        $user = Auth::user()->username;
        $oldTitle = $issue->getOriginal("title"); // 原始值https://laravel-china.org/wikis/16169
        $newTitle = $issue->title;                // 新值
        ActionLog::log("$user 把标题 $oldTitle 修改为 $newTitle");
    }
});
laravel SerializesModels

因为我们在任务类里引用了 SerializesModels 这个 trait,使得 Eloquent 模型在处理任务时可以被优雅地序列化和反序列化。如果你的队列任务类在构造器中接收了一个 Eloquent 模型,那么只有可识别出该模型的属性会被序列化到队列里。当任务被实际运行时,队列系统便会自动从数据库中重新取回完整的模型。这整个过程对你的应用程序来说是完全透明的,这样可以避免在序列化完整的 Eloquent 模式实例时所带来的一些问题。https://laravel-china.org/top...

composer require失败
cat composer.json
"monolog/monolog": "^2.0@dev",

$ composer require dees040/laravel-api-responses
    1/1:        https://packagist.laravel-china.org/p/provider-latest$0449728151603                       e355a0ee137fb34881e699652e41e3e1de11ba9c4ea7a47a312.json
    Finished: success: 1, skipped: 0, failure: 0, total: 1
Using version dev-master for dees040/laravel-api-responses
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - The requested package monolog/monolog (locked at 1.23.0, required as ^2.0@dev                       ) is satisfiable by monolog/monolog[1.23.0] but these conflict with your requiremen                       ts or minimum-stability.
  Problem 2
    - laravel/framework v5.5.42 requires monolog/monolog ~1.12 -> satisfiable by mo                       nolog/monolog[1.x-dev].
    - laravel/framework v5.5.42 requires monolog/monolog ~1.12 -> satisfiable by mo                       nolog/monolog[1.x-dev].
    - laravel/framework v5.5.42 requires monolog/monolog ~1.12 -> satisfiable by mo                       nolog/monolog[1.x-dev].
    - Can only install one of: monolog/monolog[2.x-dev, 1.x-dev].
    - Installation request for monolog/monolog ^2.0@dev -> satisfiable by monolog/m                       onolog[2.x-dev].
    - Installation request for laravel/framework (locked at v5.5.42, required as 5.                       5.*) -> satisfiable by laravel/framework[v5.5.42].
    
$composer require "monolog/monolog:~1.12"
    1/1:        https://packagist.laravel-china.org/p/provider-latest$d12a81f48a3e1dad512c1d2c375298e3a8ea414dff5000d5f345939429c6b29b.json
    Finished: success: 1, skipped: 0, failure: 0, total: 1
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
    1/1:        https://dl.laravel-china.org/monolog/monolog/c465e1144536862e03f519cb3d65e924062cabfb.zip
    Finished: success: 1, skipped: 0, failure: 0, total: 1
Package operations: 0 installs, 1 update, 0 removals
  - Removing monolog/monolog (1.23.0)
  - Installing monolog/monolog (1.x-dev c465e11):
Cloning c465e11445 from cache
Package phpoffice/phpexcel is abandoned, you should avoid using it. Use phpoffice/phpspreadsheet instead.
Writing lock file
Generating optimized autoload files
> IlluminateFoundationComposerScripts::postAutoloadDump
> @php artisan package:discover
Discovered Package: 96qbhy/hyid
Discovered Package: appstract/laravel-opcache
Discovered Package: appstract/lush-http
Discovered Package: barryvdh/laravel-debugbar
Discovered Package: barryvdh/laravel-dompdf
Discovered Package: barryvdh/laravel-ide-helper
Discovered Package: base62/base62
Discovered Package: cblink/laravel-excel-zip
Discovered Package: cblink/laravel-sso
Discovered Package: chumper/zipper
Discovered Package: encore/laravel-admin
Discovered Package: encore/redis-manager
Discovered Package: fideloper/proxy
Discovered Package: foryoufeng/laravel-generator
Discovered Package: ibrand/laravel-miniprogram-poster
Discovered Package: intervention/image
Discovered Package: itsgoingd/clockwork
Discovered Package: jacobcyl/ali-oss-storage
Discovered Package: jellybool/flysystem-upyun
Discovered Package: jenssegers/agent
Discovered Package: jenssegers/mongodb
Discovered Package: laravel-admin-ext/helpers
Discovered Package: laravel/tinker
Discovered Package: latrell/lock
Discovered Package: lubusin/laravel-decomposer
Discovered Package: maatwebsite/excel
Discovered Package: nesbot/carbon
Discovered Package: overtrue/laravel-query-logger
Discovered Package: overtrue/laravel-socialite
Discovered Package: prettus/l5-repository
Discovered Package: sentry/sentry-laravel
Discovered Package: simplesoftwareio/simple-qrcode
Discovered Package: spatie/laravel-tail
Discovered Package: tymon/jwt-auth
Discovered Package: zgldh/qiniu-laravel-storage
Package manifest generated successfully.

$ composer require dees040/laravel-api-responses
    1/1:        https://packagist.laravel-china.org/p/provider-latest$14d9ca1b35af157c565d6c564cde71c59043d7457135c5a4317471625a1db2e7.json
    Finished: success: 1, skipped: 0, failure: 0, total: 1
Using version dev-master for dees040/laravel-api-responses
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
    1/1:        https://dl.laravel-china.org/dees040/laravel-api-responses/9aec7eb323fc45e17f1dbb9c6e203d240836f91b.zip
    Finished: success: 1, skipped: 0, failure: 0, total: 1
Package operations: 1 install, 0 updates, 0 removals
  - Installing dees040/laravel-api-responses (dev-master 9aec7eb): Cloning 9aec7eb323 from cache
Package phpoffice/phpexcel is abandoned, you should avoid using it. Use phpoffice/phpspreadsheet instead.
Writing lock file
Generating optimized autoload files
> IlluminateFoundationComposerScripts::postAutoloadDump
> @php artisan package:discover

$ composer require phpoffice/phpspreadsheet
    1/2:        https://packagist.laravel-china.org/p/provider-latest$8512051929ea08e8189e440a1f5293135717f61525e93d6f4577794143032dd5.json
    2/2:        https://packagist.laravel-china.org/p/provider-2018-10$4f971ac341cf575b7ed47aa09773abb926ec0c2baad56a0da2c9eed868beb649.json
    Finished: success: 2, skipped: 0, failure: 0, total: 2
Using version dev-master for phpoffice/phpspreadsheet
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - maatwebsite/excel 3.0.9 requires phpoffice/phpspreadsheet ^1.2 -> satisfiable by phpoffice/phpspreadsheet[1.2.0, 1.2.1, 1.3.0, 1.3.1, 1.4.0, 1.4.1, 1.5.0] but these conflict with your requirements or minimum-stability.
    - maatwebsite/excel 3.0.9 requires phpoffice/phpspreadsheet ^1.2 -> satisfiable by phpoffice/phpspreadsheet[1.2.0, 1.2.1, 1.3.0, 1.3.1, 1.4.0, 1.4.1, 1.5.0] but these conflict with your requirements or minimum-stability.
    - maatwebsite/excel 3.0.9 requires phpoffice/phpspreadsheet ^1.2 -> satisfiable by phpoffice/phpspreadsheet[1.2.0, 1.2.1, 1.3.0, 1.3.1, 1.4.0, 1.4.1, 1.5.0] but these conflict with your requirements or minimum-stability.
    - Installation request for maatwebsite/excel (locked at 3.0.9) -> satisfiable by maatwebsite/excel[3.0.9].


Installation failed, reverting ./composer.json to its original content.

suping3@BJ-D-212361A MINGW64 /d/code/blog
$ composer require "phpoffice/phpspreadsheet:^1.2"
    1/3:        https://packagist.laravel-china.org/p/provider-2018-10$edb575ac09ff566f26e69fb52521dbd7b5bd90cb0e97c11c04a834f1ba157b0b.json
    2/3:        https://packagist.laravel-china.org/p/provider-latest$f7aba8aec5290950424531a654a2519842e07f0dcd995755aa8e64e7f622ad17.json
    3/3:        https://packagist.laravel-china.org/p/provider-2018-07$1f1ac5377ce1027162f91a3db54217c36e38f7ae18744629e6e89c5e6d410c78.json
    Finished: success: 3, skipped: 0, failure: 0, total: 3
./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
    1/1:        https://dl.laravel-china.org/phpoffice/phpspreadsheet/2dfd06c59825914a1a325f2a2ed13634b9d8c411.zip
    Finished: success: 1, skipped: 0, failure: 0, total: 1
Fatal error: Class "PHPUnit_Framework_TestCase" not found
https://github.com/dees040/laravel-api-responses/issues/2
vi vendor/dees040/laravel-api-responses/tests/ResponseTest.php

class ResponseTest extends PHPUnitFrameworkTestCase

$ phpunit vendor/dees040/laravel-api-responses/tests/ResponseTest.php
PHPUnit 6.5.3 by Sebastian Bergmann and contributors.

..............                                                    14 / 14 (100%)

Time: 378 ms, Memory: 16.00MB
Laravel 的 collection
$collection = new IlluminateDatabaseEloquentCollection(["item a", "item b", "item c"]);
$collection = $collection->unique();
执行时候会报错

PHP Fatal error:  Call to a member function getKey() on string in /Project/nginx/webbpm-dev.ssl.lol/vendor/laravel/framework/src/Illuminate/Database/Eloquent/Collection.php on line 259

  [SymfonyComponentDebugExceptionFatalErrorException]
  Call to a member function getKey() on string
这是因为 IlluminateDatabaseEloquentCollection 通过调用自身的 getDictionary 方法,使用根据主键去重复的逻辑覆盖了 IlluminateSupportCollection 的逻辑。

以上代码改成https://laravel-china.org/topics/18696

$collection = collect(["item a", "item b", "item c"]);
$collection = $collection->unique();
使用"mews/captcha:~2.0" 验证码图片不显示问题
SymfonyComponentDebugExceptionFatalThrowableError: Call to undefined function InterventionImageGdimagettfbbox() in file /usr/share/nginx/html/LaraBBS/vendor/intervention/image/src/Intervention/Image/Gd/Font.php on line 85

如果已经开启了gd,请参考下 https://laravel-china.org/articles/18815?#reply69185 

FROM php:7.0-fpm
RUN apt-get update && apt-get install -y 
libfreetype6-dev 
libjpeg62-turbo-dev 
libmcrypt-dev 
libpng-dev 
&& docker-php-ext-install -j$(nproc) iconv mcrypt 
&& docker-php-ext-configure gd --with-freetype-dir=/usr/include/ --with-jpeg-dir=/usr/include/ 
&& docker-php-ext-install -j$(nproc) gd
在解析外部变量时的一个问题
//https://segmentfault.com/a/1190000017051950
var_export($_POST); array ( "id" => array ( 0 => "1", 1 => "a", 2 => "2", 3 => "b", ), ) $foo["id"] = 1; $foo["id[]_text"] = 2; var_export($foo); extract($foo); var_export(get_defined_vars());
Laravel with () limit
比如如何取得每篇文章中的前10条评论
下面为错误写法:https://laravel-china.org/articles/19932

essay::with(["comment" => function($query) {
    $query->take(10)
}])
public function products()
{
    return $this->belongsToMany(Hproduct::class,"hproduct_has_type","type_id","product_id");
}

public function topTenproducts()
{
    return $this->products()->with("supplier")->where("is_sale","=",1)->limit(4);
}

public function getProdcutsWithtopTenproducts($col)
{
    $model = $this->whereIn("id",$col)->get();
    $model->each(function ($model) {
        $model->load("topTenproducts");
        });
    return $model->toArray();
}
laravel 5.5 索引长度超过限制
laravel5.4中改变了默认的编码类型(utf8 => utf8mb4), 从而使email字段索引长度超过了的默认限制长度 https://laravel-china.org/articles/18306
InnoDB 引擎中:

uft8 varchar 最大长度 255
utf8mb4 varchar 最大长度 191
设置一下 varchar 的长度不超过 191 即可
 table->string("email")->index(); varchar会使用utf8mb4编码, utf8mb4编码(4bytes)属于utf8编码(3bytes)的扩展类型,
由此可以计算索引长度为255*4+2=1022 >767
$ php artisan migrate
Migration table created successfully.

In Connection.php line 664:

  SQLSTATE[42000]: Syntax error or access violation: 1071 Specified key was t
  oo long; max key length is 1000 bytes (SQL: alter table `users` add unique
  `users_email_unique`(`email`))
golang序列化失败
ret, _ := json.Marshal(result)//https://www.hchstudio.cn/article/2018/2622/
发现是结构体定义有问题,当定义结构体时首字母必须大写才能序列化成功,这个特点在golang里面很是明显,在函数调用时首字母小写的函数在其他文件里面是调不到的。下面给出正确的结构体定义
type ResultCode struct {
    Msg  string `json:"msg"`
    Code int    `json:"code"`
    Data string `json:"data"`
}

文章版权归作者所有,未经允许请勿转载,若此文章存在违规行为,您可以联系管理员删除。

转载请注明本文地址:https://www.ucloud.cn/yun/29305.html

相关文章

  • Java开发常见问题集锦

    摘要:下面是一些常见的理解性问题,每一个问题尽量用图或代码去描述。内容全部来自,包括基本语法数组集合类泛型面向对象垃圾回收异常控制输入输出和内存。不断更新,欢迎大家提出有趣味的问题和意见。 程序员经常可以通过搜索或者记忆来完成代码,但是许多时候并不真正理解为什么那样写。也就是说,有一定经验的程序员不会犯一些低级的语法错误,但是因为不深入理解有可能造成一些高级错误,比如说运行无效率,代码难De...

    MSchumi 评论0 收藏0
  • 后端集锦

    摘要:数据异构的武器何谓数据异构,上周交易部门商品的同事过来做分享,又看到这个词,他的里面是数据库异构。其实我们以前做的事情,也是可以成为数据异构。比如我们将里面的数据持久化到里面去,就是一种数据异构的方式。 如果有人问你数据库的原理,叫他看这篇文章 一提到关系型数据库,我禁不住想:有些东西被忽视了。关系型数据库无处不在,而且种类繁多,从小巧实用的 SQLite 到强大的 Teradata ...

    shusen 评论0 收藏0
  • VueJS 开发常见问题集锦

    摘要:由于公司的前端开始转向,最近开始使用这个框架进行开发,遇到一些问题记录下来,以备后用。查了一下,发现可能是打包或是资源引用问题,目前该问题还未被妥善处理,需要通过一些来解决这个问题。为解决这个问题,中提供了方法对象受现 showImg(https://segmentfault.com/img/bVFgor?w=1280&h=720); 由于公司的前端开始转向 VueJS,最近开始使用这...

    hedge_hog 评论0 收藏0

发表评论

0条评论

awesome23

|高级讲师

TA的文章

阅读更多
最新活动
阅读需要支付1元查看
<