add provider implementations of tencentcloud

[likexian]

Hello,

This PR provides a new provider implementations of TencentCloud in the go-discover/provider sub packages.

About TencentCloud

Tencent Cloud is a secure, reliable and high-performance cloud compute service provided by Tencent. It is the 2st largest Cloud Provider in China.

[likexian]

go test -v ./provider/tencentcloud/
=== RUN   TestAddrs
2019/09/02 19:57:59 [DEBUG] discover-tencentcloud: Using region=ap-guangzhou, tag_key=consul, tag_value=test
2019/09/02 19:57:59 [DEBUG] discover-tencentcloud: Static credentials provided
2019/09/02 19:57:59 [DEBUG] discover-tencentcloud: region is ap-guangzhou
2019/09/02 19:57:59 [DEBUG] discover-tencentcloud: address type is private_v4
2019/09/02 19:57:59 [DEBUG] discover-tencentcloud: Filter instances with consul=test
2019/09/02 19:58:00 [DEBUG] discover-tencentcloud: Found 2 instances
2019/09/02 19:58:00 [DEBUG] discover-tencentcloud: Instance ins-kj81nmyo has private_v4 172.16.0.26
2019/09/02 19:58:00 [DEBUG] discover-tencentcloud: Instance ins-qgatl4is has private_v4 172.16.0.76
2019/09/02 19:58:00 [DEBUG] discover-tencentcloud: Found address: [172.16.0.26 172.16.0.76]
--- PASS: TestAddrs (0.41s)
PASS
ok      github.com/hashicorp/go-discover/provider/tencentcloud  0.423s

[hanshasselberg]

Thank you @likexian for your work! We will have a look soon!

[likexian]

Hello,
Would someone please take a review of this PR?

[alvin-huang]

I hooked this up to our CI with credentials for Tencentcloud and it passed the provider tests. @hashicorp/consul-core can someone have a look through the Go code?

[banks]

Hi @likexian!

Thanks for your patience while we worked out the testing and account gymnastics needed here for on-going support.

This looks great, I've just commented on a couple of super minor things that it would be good to clean up before we merge. Mostly removing an unnecessary dep since all of HashiCorps products end up importing everything here transitively.

Hopefully the small changes requested should take no more than a few minutes and then we can get this merged!

[likexian]

Hello @banks
Thank you for your help, I have resolved the issue about dependency.

The testing after changed passed, please have a review.

=== RUN   TestAddrs
2019/11/19 10:36:48 [DEBUG] discover-tencentcloud: Using region=ap-guangzhou, tag_key=consul, tag_value=test
2019/11/19 10:36:48 [DEBUG] discover-tencentcloud: Static credentials provided
2019/11/19 10:36:48 [DEBUG] discover-tencentcloud: region is ap-guangzhou
2019/11/19 10:36:48 [DEBUG] discover-tencentcloud: address type is private_v4
2019/11/19 10:36:48 [DEBUG] discover-tencentcloud: Filter instances with consul=test
2019/11/19 10:36:49 [DEBUG] discover-tencentcloud: Found 2 instances
2019/11/19 10:36:49 [DEBUG] discover-tencentcloud: Instance ins-i7ugrga0 has private_v4 172.16.0.144
2019/11/19 10:36:49 [DEBUG] discover-tencentcloud: Instance ins-ju9pzua2 has private_v4 172.16.0.90
2019/11/19 10:36:49 [DEBUG] discover-tencentcloud: Found address: [172.16.0.144 172.16.0.90]
--- PASS: TestAddrs (0.88s)
PASS
ok      github.com/hashicorp/go-discover/provider/tencentcloud  0.939s

[banks]

Thanks @likexian, this looks great!