Contribute document

CONTRIBUTING.md

@@ -4,26 +4,86 @@ Vald is an open source project.
 
 We appreciate your help!
 
-## Before filing an issue
+## Table of Contents
 
-If you are unsure whether you have found a bug, please consider asking in the [Vald Slack](https://join.slack.com/t/vald-community/shared_invite/zt-db2ky9o4-R_9p2sVp8xRwztVa8gfnPA) first. If the behavior you are seeing is confirmed as a bug or issue, it can easily be re-raised in the issue tracker.
+- [Contributing Issue](#Contributing-Issue)
+  - [Bug Report](#Bug-Report)
+  - [Proposal](#Proposal)
+  - [Feature Request](#Feature-Request)
+  - [Security Issue Report](#Security-Issue-Report)
+- [Contributing Source Code](#Contributing-Source-Code)
+  - [Before contributing source code](#Before-contributing-source-code)
+  - [How to contributing source code](#How-to-contributing-source-code)
+  - [Branch naming convention](#Branch-naming-convention)
 
-## Filing issues
+## Contributing Issue
 
-Sensitive security-related issues should be reported to the security channel in the [Vald Slack](https://join.slack.com/t/vald-community/shared_invite/zt-db2ky9o4-R_9p2sVp8xRwztVa8gfnPA) .
+We use [Github Issues](https://github.com/vdaas/vald/issues) to track issues within this repository.
+If you can determine the problem you are facing is a bug or issue, you can easily submit in the issues.
 
-Otherwise, when filing an issue, make sure to answer these five questions:
+If you are unsure whether you have found a bug or security-related issues, please consider asking in the [Vald Slack](https://join.slack.com/t/vald-community/shared_invite/zt-db2ky9o4-R_9p2sVp8xRwztVa8gfnPA) first. 
+If the behavior you are seeing is confirmed as a bug or issue, it can easily be re-raised in the issue tracker.
+
+### Bug Report
+
+A bug is a demonstrable problem which produce incorrect result or to behave in unintended ways.<br>
+
+Bug reports are helpful for developers who maintain the Vald project.<br>
+A good bug report should not leave others needing to ask you for more information constantly.<br>
+Please try to write as detail as possible in your bug report.
+
+When filing an issue, make sure to answer these five questions:
 
 1. What version of Vald are you using (vald docker image version)?
 2. What operating system and processor architecture are you using?
 3. What did you do?
 4. What did you expect to see?
 5. What did you see instead?
 
-Note:
-When you'd like to contribute with the new feature of some large update influencing the current Vald, we recommend getting the agreement through the authors' design review of your ISSUE.
 
-## Before contributing code
+Please submit the bug report [here](https://github.com/vdaas/vald/issues/new?assignees=&labels=type%2Fbug%2C+priority%2Fmedium%2C+team%2Fcore&template=bug_report.md&title=)
+
+### Proposal
+
+The Vald is being developed based on the design-driven process.<br>
+The significant change to the library or the architecture should be discussed first.
+
+We may ask for the detailed documentation before your proposal is accepted.<br>
+Your proposal will be reviewed, discussed and decide whether it is accepted or declined.
+
+
+Please submit the proposal [here](https://github.com/vdaas/vald/issues/new?assignees=&labels=type%2Ffeature%2C+priority%2Flow%2C+team%2Fcore&template=feature_request.md&title=)
+
+### Feature Request
+
+Feature request is welcome.
+
+Before opening an issue, please make sure your idea fits the project.<br>
+You can request the feature and convince the project maintainers to accept your feature request.
+
+Please provide the problem and solution associated with the feature request as detail as possible.
+
+
+NOTE: If you'd like to contribute the new feature which may affect the current Vald architecture or design, you should discuss with Vald team first.
+
+Please submit the feature request [here](https://github.com/vdaas/vald/issues/new?assignees=&labels=type%2Ffeature%2C+priority%2Flow%2C+team%2Fcore&template=feature_request.md&title=)
+
+### Security Issue Report
+
+The Vald team and community take serious concern about security issues.
+
+Sensitive security-related issues should be reported to the security channel in the [Vald Slack](https://join.slack.com/t/vald-community/shared_invite/zt-db2ky9o4-R_9p2sVp8xRwztVa8gfnPA).
+
+We appreciate your efforts to disclose your findings.<br>
+If the security issue is caused by a third-party module, we will contact the module owner and ask for the fix.
+
+We will consider to use another third-party module if the vulnerable module is not actively maintained anymore.
+
+Please submit the security issue report [here](https://github.com/vdaas/vald/issues/new?assignees=&labels=type%2Fsecurity%2C+priority%2Fmedium%2C+team%2Fcore%2C+team%2Fsre&template=security_issue_report.md&title=)
+
+## Contributing Source Code
+
+### Before contributing source code
 
 Follow these steps to make a contribution to any of our open source repositories:
 
@@ -34,7 +94,7 @@ Follow these steps to make a contribution to any of our open source repositories
         git config --global user.email "[email protected]"
 
 
-## Contributing code
+### How to contributing source code
 
 1. Fork the repository ( https://github.com/vdaas/vald/fork )
 2. Create your feature branch (git checkout -b [`[type]/[area]/[description]`](#Branch-naming-convention))
@@ -44,7 +104,7 @@ Follow these steps to make a contribution to any of our open source repositories
 6. Create new Pull Request
 
 
-We favor pull requests with very small, single commits with a single purpose.
+Each pull request and commit should be small enough to contain only one purpose. 
 
 Your pull request is much more likely to be accepted if:
 
@@ -55,7 +115,7 @@ Your pull request is much more likely to be accepted if:
 * Your pull request is small and focused with a clear message that conveys the intent of your change
 
 
-## Branch naming convention
+### Branch naming convention
 
 Name your branches with prefixes: `[type]/[area]/[description]`