google app engine devfest 200810 external
DESCRIPTION
TRANSCRIPT
Google App Engine 快速入门
2008 年 10 月 24 日
日程• App Engine 简介• 应用开发详例• APIs 例子• 其他用例和展望
基本概念
创建一个 Web 应用，往往需要自己干很多体力活…
Google 提供的成套解决方案
开箱即用 , 易上手
应用详例
我们要开发 :
• 从 twitter 获取带有某个关键字的所有 “ tweet”, 算出在此话题内发言最多的用户
• 为每个用户生成一个总结页面 , 包括此用户的头像 , 基本资料 , 还有在这个话题下的总结页面 .
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http://tag080808.appspot.com
0. 注册 App Engine
• Google App Engine:http://appengine.google.com
• 如果无法接收短信验证码 :http://appengine.google.com/waitlist/sms_issues
1. app.yaml 配置文件
application: tag080808version: 2runtime: pythonapi_version: 1
handlers:- url: /static static_dir: static
- url: /admin.* script: admin.py login: admin
- url: /.* script: main.py
application: tag080808version: 2runtime: pythonapi_version: 1
handlers:- url: /static static_dir: static
- url: /admin.* script: admin.py login: admin
- url: /.* script: main.py
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from google.appengine.ext import db
class Tweet(db.Model): text = db.StringProperty() id = db.IntegerProperty() from_user = db.StringProperty() created_at = db.DateTimeProperty() iso_language_code = db.StringProperty() profile_image_url = db.LinkProperty()
class User(db.Model): name = db.StringProperty() screen_name = db.StringProperty() followers_count = db.IntegerProperty() count = db.IntegerProperty() id = db.IntegerProperty() description = db.StringProperty() ...
from google.appengine.ext import db
class Tweet(db.Model): text = db.StringProperty() id = db.IntegerProperty() from_user = db.StringProperty() created_at = db.DateTimeProperty() iso_language_code = db.StringProperty() profile_image_url = db.LinkProperty()
class User(db.Model): name = db.StringProperty() screen_name = db.StringProperty() followers_count = db.IntegerProperty() count = db.IntegerProperty() id = db.IntegerProperty() description = db.StringProperty() ...
2. Data Model
3. 后台抓取数据
class FetchHandler(webapp.RequestHandler): def get(self): url =("http://search.twitter.com/search.json?q=%%23080808" "&page=%d" % page) response = urlfetch.fetch(url) if response.status_code == 200: data = simplejson.loads(response.content) results = data["results"] for result in results tweet = datamodel.Tweet( id = result["id"], from_user = result["from_user"], text = result["text"], created_at = parse_time(result["created_at"]) ) tweet.put() ......
class FetchHandler(webapp.RequestHandler): def get(self): url =("http://search.twitter.com/search.json?q=%%23080808" "&page=%d" % page) response = urlfetch.fetch(url) if response.status_code == 200: data = simplejson.loads(response.content) results = data["results"] for result in results tweet = datamodel.Tweet( id = result["id"], from_user = result["from_user"], text = result["text"], created_at = parse_time(result["created_at"]) ) tweet.put() ......
class DefaultPage(webapp.RequestHandler): def get(self): top_users = datamodel.User.gql("ORDER BY count DESC LIMIT 20") template_values = {"top_users": top_users} path = os.path.join(os.path.dirname(__file__),
"templates/default.html") self.response.headers["Content-Type"] = "text/html" self.response.out.write(template.render(path, template_values))
class DefaultPage(webapp.RequestHandler): def get(self): top_users = datamodel.User.gql("ORDER BY count DESC LIMIT 20") template_values = {"top_users": top_users} path = os.path.join(os.path.dirname(__file__),
"templates/default.html") self.response.headers["Content-Type"] = "text/html" self.response.out.write(template.render(path, template_values))
4. 排行榜显示页面
class DefaultPage(webapp.RequestHandler): def get(self): top_users = datamodel.User.gql("ORDER BY count DESC LIMIT 20") template_values = { "top_users": top_users } path = os.path.join(os.path.dirname(__file__), "templates/default.html") self.response.headers["Content-Type"] = "text/html" self.response.out.write(template.render(path, template_values))
class DefaultPage(webapp.RequestHandler): def get(self): top_users = datamodel.User.gql("ORDER BY count DESC LIMIT 20") template_values = { "top_users": top_users } path = os.path.join(os.path.dirname(__file__), "templates/default.html") self.response.headers["Content-Type"] = "text/html" self.response.out.write(template.render(path, template_values))
4. 排行榜显示页面
class DefaultPage(webapp.RequestHandler): def get(self): if memcache.get("top_users") is None: top_users = datamodel.User.gql("ORDER BY count DESC LIMIT 20") memcache.set("top_users", simplejson.dumps(top_users)) else: top_users = memcache.get("top_users") template_values = { "top_users": top_users } path = os.path.join(os.path.dirname(__file__), "templates/default.html") self.response.headers["Content-Type"] = "text/html" self.response.out.write(template.render(path, template_values))
class DefaultPage(webapp.RequestHandler): def get(self): if memcache.get("top_users") is None: top_users = datamodel.User.gql("ORDER BY count DESC LIMIT 20") memcache.set("top_users", simplejson.dumps(top_users)) else: top_users = memcache.get("top_users") template_values = { "top_users": top_users } path = os.path.join(os.path.dirname(__file__), "templates/default.html") self.response.headers["Content-Type"] = "text/html" self.response.out.write(template.render(path, template_values))
4. 排行榜显示页面
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<!DOCTYPE html><html> ... <body> ... {% for user in top_users %} <dl> <dt><a href=“/tweeter/{{ user.user }}”>{{ user.name }}</a></dt> <dd>{{user.count }}</dd> </dl> {% endfor %} ... </body>
<!DOCTYPE html><html> ... <body> ... {% for user in top_users %} <dl> <dt><a href=“/tweeter/{{ user.user }}”>{{ user.name }}</a></dt> <dd>{{user.count }}</dd> </dl> {% endfor %} ... </body>
5. HTML 模板 default.html
6. 开发调试环境
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7. 部署！
appcfg.py update application_folder
http://tag080808.appspot.com
或者使用自己的域名 !
http://me.tag080808.com
8. 监测自己的应用
其它 APIs
Memcache API为常用页面和数据库查询加速
Mail API自动发送邮件
URL Fetch API抓取其他互联网资源
Users API与 Google 账户轻易整合
Images API基本图片处理
zhen-gong-fu.appspot.comcode.google.com/p/zhen-gong-fu
其它应用与展望未来
和 Google Apps 的整合
Map.yuanpei.org
Google App Engine + OpenSocial
TBD: Focus on 是男人系列
http://code.google.com/apis/opensocial/articles/appengine-0.8.html
Google App Engine + OpenSocial
TBD: Focus on 是男人系列
PREVIEW
现状…
• 500 MB 存储空间• 每天 2 GB 流量• 大约可容纳每月 500 万的访问量• 未来可付费升级
未来… • 大文件存取• 大批量数据上传和导出工具• 付费 : 可购买更多配额• 更多语言的支持• 运行状况监控站点
教程、文档、资源、精品文章…http://code.google.com/appengine
作品展示…http://appgallery.appspot.com/
示例代码下载…http://code.google.com/p/google-app-engine-samples/
谢谢 !