David Pilato efffb946e2 Fix ec2 discovery when used with IAM profiles.
Here is what is happening without this fix when you try to connect to ec2 APIs:

```
[2016-10-20T12:41:49,925][DEBUG][c.a.a.AWSCredentialsProviderChain] Unable to load credentials from EnvironmentVariableCredentialsProvider: Unable to load AWS credentials from environment variables (AWS_ACCESS_KEY_ID (or AWS_ACCESS_KEY) and AWS_SECRET_KEY (or AWS_SECRET_ACCESS_KEY))
[2016-10-20T12:41:49,926][DEBUG][c.a.a.AWSCredentialsProviderChain] Unable to load credentials from SystemPropertiesCredentialsProvider: Unable to load AWS credentials from Java system properties (aws.accessKeyId and aws.secretKey)
[2016-10-20T12:41:49,926][DEBUG][c.a.a.AWSCredentialsProviderChain] Unable to load credentials from com.amazonaws.auth.profile.ProfileCredentialsProvider@1ad14091: access denied ("java.io.FilePermission" "/home/ubuntu/.aws/credentials" "read")
[2016-10-20T12:41:49,927][DEBUG][c.a.i.EC2MetadataClient  ] Connecting to EC2 instance metadata service at URL: http://169.254.169.254/latest/meta-data/iam/security-credentials/
[2016-10-20T12:41:49,951][DEBUG][c.a.i.EC2MetadataClient  ] Connecting to EC2 instance metadata service at URL: http://169.254.169.254/latest/meta-data/iam/security-credentials/discovery-tests
[2016-10-20T12:41:49,965][DEBUG][c.a.a.AWSCredentialsProviderChain] Unable to load credentials from InstanceProfileCredentialsProvider: Unable to parse Json String.
[2016-10-20T12:41:49,966][INFO ][o.e.d.e.AwsEc2UnicastHostsProvider] [dJfktmE] Exception while retrieving instance list from AWS API: Unable to load AWS credentials from any provider in the chain
[2016-10-20T12:41:49,967][DEBUG][o.e.d.e.AwsEc2UnicastHostsProvider] [dJfktmE] Full exception:
com.amazonaws.AmazonClientException: Unable to load AWS credentials from any provider in the chain
	at com.amazonaws.auth.AWSCredentialsProviderChain.getCredentials(AWSCredentialsProviderChain.java:131) ~[aws-java-sdk-core-1.10.69.jar:?]
	at com.amazonaws.services.ec2.AmazonEC2Client.invoke(AmazonEC2Client.java:11117) ~[aws-java-sdk-ec2-1.10.69.jar:?]
	at com.amazonaws.services.ec2.AmazonEC2Client.describeInstances(AmazonEC2Client.java:5403) ~[aws-java-sdk-ec2-1.10.69.jar:?]
	at org.elasticsearch.discovery.ec2.AwsEc2UnicastHostsProvider.fetchDynamicNodes(AwsEc2UnicastHostsProvider.java:116) [discovery-ec2-5.0.0.jar:5.0.0]
	at org.elasticsearch.discovery.ec2.AwsEc2UnicastHostsProvider$DiscoNodesCache.refresh(AwsEc2UnicastHostsProvider.java:234) [discovery-ec2-5.0.0.jar:5.0.0]
	at org.elasticsearch.discovery.ec2.AwsEc2UnicastHostsProvider$DiscoNodesCache.refresh(AwsEc2UnicastHostsProvider.java:219) [discovery-ec2-5.0.0.jar:5.0.0]
	at org.elasticsearch.common.util.SingleObjectCache.getOrRefresh(SingleObjectCache.java:54) [elasticsearch-5.0.0.jar:5.0.0]
	at org.elasticsearch.discovery.ec2.AwsEc2UnicastHostsProvider.buildDynamicNodes(AwsEc2UnicastHostsProvider.java:102) [discovery-ec2-5.0.0.jar:5.0.0]
	at org.elasticsearch.discovery.zen.ping.unicast.UnicastZenPing.sendPings(UnicastZenPing.java:358) [elasticsearch-5.0.0.jar:5.0.0]
	at org.elasticsearch.discovery.zen.ping.unicast.UnicastZenPing$1.doRun(UnicastZenPing.java:272) [elasticsearch-5.0.0.jar:5.0.0]
	at org.elasticsearch.common.util.concurrent.ThreadContext$ContextPreservingAbstractRunnable.doRun(ThreadContext.java:504) [elasticsearch-5.0.0.jar:5.0.0]
	at org.elasticsearch.common.util.concurrent.AbstractRunnable.run(AbstractRunnable.java:37) [elasticsearch-5.0.0.jar:5.0.0]
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [?:1.8.0_91]
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [?:1.8.0_91]
	at java.lang.Thread.run(Thread.java:745) [?:1.8.0_91]
```

For whatever reason, it can not parse what is coming back from http://169.254.169.254/latest/meta-data/iam/security-credentials/discovery-tests.

But, if you wrap the code within an `AccessController.doPrivileged()` call, then it works perfectly.

Closes #21039.

(cherry picked from commit abfdc70)
2016-10-20 17:19:22 +02:00
..