November 2021
Beginner to intermediate
239 pages
4h 15m
Chinese
Content preview from Dapr学习手册
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
状态
｜
101
储空间的额外细节。我们希望在你尝试实现你自己的
Dapr
兼容的状态存储时
这些信息能有所帮助。
2.5.1 Redis
Redis
是内存数据结构存储。它提供了一个在性能和可靠性之间有着良好平衡
的集群存储解决方案，而且它很容易配置。这就是为什么
Redis
是
Dapr
的默
认状态存储。
Dapr
使用
hashes
而不是
sets
来保存数据。使用
hashes
的主要原因是要把
数据元素和它相关的
ETag
作为单个单元。在本文编写时，
Redis
还不支持
ETag
，所以
Dapr
使用一个不断递增的版本号作为
ETag
。为了确保数据元素
更新和
ETag
维护作为单一事务处理，
Dapr
使用
Lua
脚本来执行所有的
Set
和
Delete
请求，因为
Redis
在单一事务中执行
Lua
脚本（
https://www.lua.
org
）中的所有命令。例如，以下
Lua
脚本用于更新一个
key
：
local var1 = redis.pcall("HGET", KEYS[1], "version");
if type(var1) == "table" then
redis.call("DEL", KEYS[1]);
end;
if not var1 or type(var1) == "table" or var1 == "" or
var1 == ARGV[1] or ARGV[1] == "0" then
redis.call("HSET", KEYS[1], "data", ARGV[2])
return ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.