AppSync：使用AWS_IAM身份验证时以$ context获取用户信息 [英] AppSync: Get user information in $context when using AWS_IAM auth
问题描述
在AppSync中，当您使用Cognito用户池作为您的身份验证授权时，您会得到
In AppSync, when you use Cognito User Pools as your auth setting your identity you get
identity:
{ sub: 'bcb5cd53-315a-40df-a41b-1db02a4c1bd9',
issuer: 'https://cognito-idp.us-west-2.amazonaws.com/us-west-2_oicu812',
username: 'skillet',
claims:
{ sub: 'bcb5cd53-315a-40df-a41b-1db02a4c1bd9',
aud: '7re1oap5fhm3ngpje9r81vgpoe',
email_verified: true,
event_id: 'bb65ba5d-4689-11e8-bee7-2d0da8da81ab',
token_use: 'id',
auth_time: 1524441800,
iss: 'https://cognito-idp.us-west-2.amazonaws.com/us-west-2_oicu812',
'cognito:username': 'skillet',
exp: 1524459387,
iat: 1524455787,
email: 'myemail@nope.com' },
sourceIp: [ '11.222.33.200' ],
defaultAuthStrategy: 'ALLOW',
groups: null }
但是，当您使用AWS_IAM auth时，会得到
However when you use AWS_IAM auth you get
identity:
{ accountId: '12121212121', //<--- my amazon account ID
cognitoIdentityPoolId: 'us-west-2:39b1f3e4-330e-40f6-b738-266682302b59',
cognitoIdentityId: 'us-west-2:a458498b-b1ac-46c1-9c5e-bf932bad0d95',
sourceIp: [ '33.222.11.200' ],
username: 'AROAJGBZT5A433EVW6O3Q:CognitoIdentityCredentials',
userArn: 'arn:aws:sts::454227793445:assumed-role/MEMORYCARDS-CognitoAuthorizedRole-dev/CognitoIdentityCredentials',
cognitoIdentityAuthType: 'authenticated',
cognitoIdentityAuthProvider: '"cognito-idp.us-west-2.amazonaws.com/us-west-2_HighBob","cognito-idp.us-west-2.amazonaws.com/us-west-2_HighBob:CognitoSignIn:1a072f08-5c61-4c89-807e-417d22702eb7"' }
文档说，这是预期的， https：// docs .aws.amazon.com / appsync / latest / devguide / resolver-context-reference.htm l 。
但是，如果使用连接到Cognito的 AWS_IAM （必须具有未经身份验证的访问权限），应该如何获取用户的用户名，电子邮件，等等？使用 AWS_IAM 类型Auth时，我需要访问用户的声明。
The Docs says that this is expected, https://docs.aws.amazon.com/appsync/latest/devguide/resolver-context-reference.html .
However, if you use AWS_IAM connected to Cognito (which is required to have unauthenticated access), how are you supposed to get at the User's username, email, sub, etc? I need access to the user's claims when using AWS_IAM type Auth.
推荐答案
这是我的答案。 appSync客户端库中存在一个错误，它将覆盖所有自定义标头。此后已解决。现在，您可以传递自定义标头，这些标头将一直传递到您的解析器，这些传递给我的lambda函数（同样，请注意，我使用的是lambda datasourcres，而不是dynamoDB）。
Here is my answer. There was a bug in the appSync client library that would overwrite all custom headers. That has since been fixed. Now you can pass down custom headers that will make it all the way to you resolvers, which I pass to my lambda functions (again, note I am using lambda datasourcres and not using dynamoDB).
因此，我将登录的JWT附加到客户端，并将服务器端附加到我的lambda函数中，然后对其进行解码。您需要由cognito创建的公钥来验证JWT。 （您不需要秘密密钥。）与每个用户池关联的众所周知的密钥 URL是我第一次启动Lambda时ping的，但就像我的mongoDB连接一样，它在lambda调用之间保持不变（
So I attach my logged in JWT on the client side and, server side in my lambda function, I decode it. You need the public key created by cognito to validate the JWT. (YOU DO NOT NEED A SECRET KEY.) There is a "well known key" url associated with every user pool which I ping the first time my lambda is spun up but, just like my mongoDB connection, it is persisted between lambda calls (at least for a while.)
这里是lambda解析器...
Here is lambda resolver...
const mongoose = require('mongoose');
const jwt = require('jsonwebtoken');
const jwkToPem = require('jwk-to-pem');
const request = require('request-promise-native');
const _ = require('lodash')
//ITEMS THAT SHOULD BE PERSISTED BETWEEN LAMBDA EXECUTIONS
let conn = null; //MONGODB CONNECTION
let pem = null; //PROCESSED JWT PUBLIC KEY FOR OUR COGNITO USER POOL, SAME FOR EVERY USER
exports.graphqlHandler = async (event, lambdaContext) => {
// Make sure to add this so you can re-use `conn` between function calls.
// See https://www.mongodb.com/blog/post/serverless-development-with-nodejs-aws-lambda-mongodb-atlas
lambdaContext.callbackWaitsForEmptyEventLoop = false;
try{
////////////////// AUTHORIZATION/USER INFO /////////////////////////
//ADD USER INFO, IF A LOGGED IN USER WITH VALID JWT MAKES THE REQUEST
var token = _.get(event,'context.request.headers.jwt'); //equivalen to "token = event.context.re; quest.headers.alexauthorization;" but fails gracefully
if(token){
//GET THE ID OF THE PUBLIC KEY (KID) FROM THE TOKEN HEADER
var decodedToken = jwt.decode(token, {complete: true});
// GET THE PUBLIC KEY TO NEEDED TO VERIFY THE SIGNATURE (no private/secret key needed)
if(!pem){
await request({ //blocking, waits for public key if you don't already have it
uri:`https://cognito-idp.${process.env.REGION}.amazonaws.com/${process.env.USER_POOL_ID}/.well-known/jwks.json`,
resolveWithFullResponse: true //Otherwise only the responce body would be returned
})
.then(function ( resp) {
if(resp.statusCode != 200){
throw new Error(resp.statusCode,`Request of JWT key with unexpected statusCode: expecting 200, received ${resp.statusCode}`);
}
let {body} = resp; //GET THE REPSONCE BODY
body = JSON.parse(body); //body is a string, convert it to JSON
// body is an array of more than one JW keys. User the key id in the JWT header to select the correct key object
var keyObject = _.find(body.keys,{"kid":decodedToken.header.kid});
pem = jwkToPem(keyObject);//convert jwk to pem
});
}
//VERIFY THE JWT SIGNATURE. IF THE SIGNATURE IS VALID, THEN ADD THE JWT TO THE IDENTITY OBJECT.
jwt.verify(token, pem, function(error, decoded) {//not async
if(error){
console.error(error);
throw new Error(401,error);
}
event.context.identity.user=decoded;
});
}
return run(event)
} catch (error) {//catch all errors and return them in an orderly manner
console.error(error);
throw new Error(error);
}
};
//async/await keywords used for asynchronous calls to prevent lambda function from returning before mongodb interactions return
async function run(event) {
// `conn` is in the global scope, Lambda may retain it between function calls thanks to `callbackWaitsForEmptyEventLoop`.
if (conn == null) {
//connect asyncoronously to mongodb
conn = await mongoose.createConnection(process.env.MONGO_URL);
//define the mongoose Schema
let mySchema = new mongoose.Schema({
///my mongoose schem
});
mySchema('toJSON', { virtuals: true }); //will include both id and _id
conn.model('mySchema', mySchema );
}
//Get the mongoose Model from the Schema
let mod = conn.model('mySchema');
switch(event.field) {
case "getOne": {
return mod.findById(event.context.arguments.id);
} break;
case "getAll": {
return mod.find()
} break;
default: {
throw new Error ("Lambda handler error: Unknown field, unable to resolve " + event.field);
} break;
}
}
这比我的其他坏答案要好因为您并不总是查询数据库来获取客户端已经拥有的信息。根据我的经验，速度快3倍。
This is WAY better than my other "bad" answer because you are not always querying a DB to get info that you already have on the client side. About 3x faster in my experience.
这篇关于AppSync：使用AWS_IAM身份验证时以$ context获取用户信息的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
