安装
yarn add koa-passport passport-local
yarn add koa-passport passport-local先看下passport.js登录策略，判断用户和密码
const passport = require('koa-passport')
const LocalStrategy = require('passport-local').Strategy
const User = require('../../dbs/models/users')

passport.use(new LocalStrategy((username, password, done) => {
User.findOne({username}, (err, user) => {

if (err) return done(err)

if (!user) return done(null, false, {message: '用户不存在'})

if (user.password !== password) return done(null, false, {message: '密码错误'})

return done(null, user)
})
}))

passport.serializeUser((user, done) => {
done(null, user)
})

passport.deserializeUser((user, done) => {
done(null, user)
})

module.exports = passport


const passport = require('koa-passport')
const LocalStrategy = require('passport-local').Strategy
const User = require('../../dbs/models/users')

passport.use(new LocalStrategy((username, password, done) => {
User.findOne({username}, (err, user) => {

if (err) return done(err)

if (!user) return done(null, false, {message: '用户不存在'})

if (user.password !== password) return done(null, false, {message: '密码错误'})

return done(null, user)
})
}))

passport.serializeUser((user, done) => {
done(null, user)
})

passport.deserializeUser((user, done) => {
done(null, user)
})

module.exports = passport

在入口中挂载passport
app.use(passport.initialize())
app.use(passport.session())

app.use(passport.initialize())
app.use(passport.session())
这时候passport策略配置完成登录接口实现
router.post('/signin', async ctx => {
return Passport.authenticate('local', (err, user, info, status) => {

if (err) {

ctx.body = {

code:-1,

msg:err

}

}else {

if (user) {

ctx.body = {

code:0,

msg:'登录成功',

user

}

return ctx.login(user)

} else {

ctx.body = {

code:1,

msg:info

}

}

}
})(ctx)
})


router.post('/signin', async ctx => {
return Passport.authenticate('local', (err, user, info, status) => {

if (err) {

ctx.body = {

code:-1,

msg:err

}

}else {

if (user) {

ctx.body = {

code:0,

msg:'登录成功',

user

}

return ctx.login(user)

} else {

ctx.body = {

code:1,

msg:info

}

}

}
})(ctx)
})

用户是否登录
router.get('/getUser', async ctx => {
if (ctx.isAuthenticated()){

const {username, email} = ctx.session.passport.user

ctx.body = {

username,

email

}
} else {

ctx.body = {

username: '',

email: ''

}
}
})


router.get('/getUser', async ctx => {
if (ctx.isAuthenticated()){

const {username, email} = ctx.session.passport.user

ctx.body = {

username,

email

}
} else {

ctx.body = {

username: '',

email: ''

}
}
})

用户退出
router.get('/exit', async ctx => {
await ctx.logout()
if (!ctx.isAuthenticated()) {

ctx.body = {

code:0

}
} else {

ctx.body = {

code:-1

}
}
})


router.get('/exit', async ctx => {
await ctx.logout()
if (!ctx.isAuthenticated()) {

ctx.body = {

code:0

}
} else {

ctx.body = {

code:-1

}
}
})

分析分析分析通过passport.serializeUser函数定义序列化操作，调用ctx.login()会触发序列化操作通过passport.deserializeUser函数定义反序列化操作，在session中如果存在passport:{user:'Susan'}会触发反序列化操作通过passport.use(new LocalStrategy('local', ...)) 注册策略，调用passport.authenticate('local',...)调用策略app.use(passport.initialize()) 会在ctx挂载以下方法
ctx.state.user 认证用户
ctx.login(user) 登录用户
ctx.logout() 用户退出登录
ctx.isAuthenticated() 判断是否认证