Google云计算GAE开发的一个IT技术推荐应用
IT Technology Network是用Google App Engine - Google Code google的云计算服务开发的一个网站。
- IT Technology Network 是一个专注于IT技术的网站，包括软件开发、IT业界、Java、数据库、Unix、Web开发、开源项目、互联网等新闻和博客。
- 目标是提供一个有质量保证、简洁、经常更新的IT技术内容和搜索服务。
- IT Technology Network 其实也就是国内IT技术网站的一个聚合网站，例如，腾讯IT，Linux伊甸园，ChinaUnix，JavaEye博客，Java博客，ITPUB技术门户
这算是Google App Engine的试用应用吧，渐渐地才发现云计算不是一个概念，而中国的云计算可能还落后很多，而这个又像马云说的那样，云计算可能蕴藏颠覆性力量。“我最怕的是老酒装新瓶的东西，你看不清他在玩什么，突然爆发出来最可怕。假如从来没有听说的，这个不可怕。雅虎当年做搜索引擎，然后Google出来了，雅虎很多人认为跟我们也差不多，后来几乎把他们搞死。”
Google App Engine for Java数据备份下载
It is possible to use python tool bulkloader.py to create datastore backup of GAE Java app. You just have to set up remote_api by adding following lines to web.xml: After that you can use bulkloader.py with --dump to download backup and with --restore to upload backup to datastore. You can also use the You can download and upload every entity of a kind in a format suitable for backup and restore, all without writing any additional code or configuration. To download all entities of all kinds, run the folowing command: To start a data download, run If you are using a Google Apps domain name and need appcfg.py to sign in using an account on that domain, you must specify the If the transfer is interrupted, you can resume the transfer from where it left off using the <?xml version="1.0" encoding="utf-8"?>
<web-app>
<!-- Add this to your web.xml to enable remote API on Java. -->
<servlet>
<servlet-name>remoteapi</servlet-name>
<servlet-class>com.google.apphosting.utils.remoteapi.RemoteApiServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>remoteapi</servlet-name>
<url-pattern>/remote_api</url-pattern>
</servlet-mapping>
<security-constraint>
<web-resource-collection>
<web-resource-name>remoteapi</web-resource-name>
<url-pattern>/remote_api</url-pattern>
</web-resource-collection>
<auth-constraint>
<role-name>admin</role-name>
</auth-constraint>
</security-constraint>
</web-app> --kind=... argument to download all entities of a specific kind:
bulkloader.py --dump --app_id=<app-id> --kind=<kind> --url=http://<appname>.appspot.com/remote_api --filename=<data-filename>
bulkloader.py --dump --app_id=<app-id> --url=http://<appname>.appspot.com/remote_api --filename=<data-filename>
Downloading Data from App Engine
appcfg.py download_data with the appropriate arguments:
appcfg.py download_data --config_file=album_loader.py --filename=album_data_archive.csv --kind=Album <app-directory>
--auth_domain=... option, whose value is your domain name.--db_filename=... and --result_db_filename=... arguments. These arguments are the names of the progress file and the results file created by the tool, which are either names you provided with the arguments when you started the transfer, or default names that include a timestamp. This assumes you have sqlite3 installed, and did not disable progress files with --db_filename=skip.