我在jekyll帖子上有以下标题,其中有一位作者"usman"生成了这篇文章.我希望有类似"作者:usman,someone_else"之类的东西,所以同事也可以为这篇文章做出贡献.这可能吗？我该如何设置它.
---
layout: post
title: The pitfalls of building services using Google App Engine -- Part I
date: 2013-02-24 08:18:17
author: usman
categories:
- System Admin
tags:
- GAE
---
我看了一下我正在使用的主题的帖子模板,它有以下几行:
{% assign author = site.authors[page.author] %}
这显然只会支持一位作者,有没有办法让这两位作者都能获得？即page.author [0]例如？
1)是否存在使用异步I/O而不是线程池的aws sdk的实现？我正在开发一个高度可扩展的Web服务,并且分析显示CPU正在浪费大量循环来管理来自amazon的网络I/O.
2)当前客户端使用Apache Http Client,如果我找不到异步实现,我将分叉我自己的版本来实现它.我在考虑使用Jetty Http Client.混合Jetty和Apache库是不好的形式？还有更好的选择吗？
有没有其他人遇到这个例外？我们昨晚在负载测试中看到了它.主机名是正确的,通常正常.它昨晚刚开始抛出这个例外.无论是amanzon的随机DNS失败,还是Aws SDK for Java在加载时都会出现意外情况.
> Caused by: java.net.UnknownHostException: sdb.amazonaws.com
at java.net.Inet6AddressImpl.lookupAllHostAddr(Native Method)
at java.net.InetAddress$1.lookupAllHostAddr(InetAddress.java:867)
at java.net.InetAddress.getAddressFromNameService(InetAddress.java:1246)
at java.net.InetAddress.getAllByName0(InetAddress.java:1197)
at java.net.InetAddress.getAllByName(InetAddress.java:1128)
at java.net.InetAddress.getAllByName(InetAddress.java:1064)
at org.apache.http.impl.conn.DefaultClientConnectionOperator.resolveHostname(DefaultClientConnectionOperator.java:242)
at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:130)
at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:149)
at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:121)
at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:561)
at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:415)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:820)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:754)
at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:732)
at com.amazonaws.http.AmazonHttpClient.executeHelper(AmazonHttpClient.java:266)
服务器如何实际识别请求客户端地址(IP)并发送响应？是否有可能在GAE中获取请求客户端的IP地址？
我正在运行maven 3上的构建并尝试下载相同jar的许多不同版本,我甚至没有将jar指定为依赖项.知道为什么这样做吗？
Downloading: http://download.java.net/maven/2/org/codehaus/jackson/jackson-core-asl/maven-metadata.xml
Downloading: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/maven-metadata.xml
Downloading: http://repo1.maven.org/maven2/org/codehaus/jackson/jackson-core-asl/maven-metadata.xml
Downloaded: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/maven-metadata.xml (3 KB at 10.8 KB/sec)
Downloaded: http://repo1.maven.org/maven2/org/codehaus/jackson/jackson-core-asl/maven-metadata.xml (2 KB at 1.8 KB/sec)
Downloading: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.0/jackson-core-asl-1.4.0.pom
Downloaded: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.0/jackson-core-asl-1.4.0.pom (1016 B at 5.0 KB/sec)
Downloading: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.1/jackson-core-asl-1.4.1.pom
Downloaded: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.1/jackson-core-asl-1.4.1.pom (1016 B at 5.4 KB/sec)
Downloading: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.2/jackson-core-asl-1.4.2.pom
Downloaded: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.2/jackson-core-asl-1.4.2.pom (1016 B at 5.4 KB/sec)
Downloading: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.3/jackson-core-asl-1.4.3.pom
Downloaded: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.3/jackson-core-asl-1.4.3.pom (1016 B at 5.5 KB/sec)
Downloading: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.4/jackson-core-asl-1.4.4.pom
Downloaded: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.4/jackson-core-asl-1.4.4.pom (1016 B at 5.0 KB/sec)
Downloading: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.5/jackson-core-asl-1.4.5.pom
Downloaded: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.4.5/jackson-core-asl-1.4.5.pom (1016 B at 5.4 KB/sec)
Downloading: http://CorporateRepo/org/codehaus/jackson/jackson-core-asl/1.5.0-SNAPSHOT/maven-metadata.xml
Downloading: http://download.java.net/maven/2/org/codehaus/jackson/jackson-core-asl/1.5.0-SNAPSHOT/maven-metadata.xml …我在服务器端广泛使用了Jackson从POJO转换为JSON,并且想知道是否有类似的Objective C/iPhone SDK库,反之亦然.Objective C确实提供了反射,因此应该可以制作类似Jackson的东西.
是否可以附加到Amazon DynamoDB表中多值属性中的值列表？我无法使用put请求弄明白.如果可能的话,我想避免读取,更新,写入逻辑.
A^2+B^2+C^2+D^2 = N给定一个整数N,打印出ABCD解决方程的整数值的所有可能组合.
我猜我们可以比蛮力更好.
我经常使用var options = options || {}默认为空对象的方式.它通常用于初始化选项对象,以防它未在函数调用的参数中传递.
事情是我在几个地方(博客文章,源代码)阅读,options || (options = {})更好地表达了开发人员的意图.有人可以详细说明吗？我没有看到两者之间的功能差异,所以我必须在这里找到一些东西.
---编辑
我在几个地方看过Backbone.js源代码,比如https://github.com/documentcloud/backbone/blob/0.9.2/backbone.js#L273
我想我也是在jQuery的源代码中也看到过它.并且在多个Js写作风格指南中蓬勃发展.
---编辑2代码示例:
var func = function(param, options) {
// How I do it
var options = options || {};
// How I should do it in the "same" way
options = options || {};
// The "other" way
options || (options = {});
}