Adding style guide

STYLE-GUIDE.md

@@ -0,0 +1,161 @@
+# Mattermost Style Guide
+
+1. [GO](#go)
+2. [Javascript](#javascript)
+3. [React/JSX](#jsx)
+
+
+## Go
+
+All go code must follow the golang official [Style Guide](https://golang.org/doc/effective_go.html)
+
+In addition all code must be run though the official go formater tool [gofmt](https://golang.org/cmd/gofmt/)
+
+
+## Javascript
+
+Part of the buld process is running ESLint. ESLint is the final athority on all style issues. PRs will not be accepted unless there are no errors or warnings running ESLint. The ESLint configuration file can be found in: [web/react/.eslintrc](https://github.com/mattermost/platform/blob/master/web/react/.eslintrc.json)
+
+Instructions on how to use ESLint with your favourite editor can be found here: [http://eslint.org/docs/user-guide/integrations](http://eslint.org/docs/user-guide/integrations)
+
+The following is an abriged version of the [Airbnb Javascript Style Guide](https://github.com/airbnb/javascript/blob/master/README.md#airbnb-javascript-style-guide-), with modifications. Anything that is unclear here follow that guide. If there is a conflict, follow what is said below. 
+
+### Whitespace
+
+- Indentaiton is four spaces
+- Use a space before the leading brace
+- Use one space between the comma and the next argument in a bracketed list. No other space.
+- Use whitespace to make code more readable.
+- Do not use more than one newline to separate code blocks. 
+- Do not use a newline as the first line of a function
+
+```javascript
+// Correct
+function myFunction(parm1, parm2) {
+    stuff...;
+  
+    morestuff;
+}
+
+// Incorrect
+function myFunction ( parm1, parm2 ){
+  stuff...;
+    
+    
+  morestuff;
+}
+
+```
+
+### Semicolons
+
+- You must use them always
+
+```javascript
+// Correct
+var x = 1;
+
+// Incorrect
+var x = 1
+```
+
+### Variables
+
+- Declarations must always use var, let or const.
+- Perfer let or const over var.
+
+```javascript
+// Correct
+let x = 4;
+
+// OK
+var x = 4;
+
+// Incorrect
+x = 4;
+```
+
+### Blocks
+
+- Braces must be used on all multi-line blocks.
+- Braces must start on the same line as the statment starting the block.
+- Else and else if must be on the same line as the if block closing brace.
+
+```javascript
+// Correct
+if (somthing) {
+    stuff...;
+} else if (otherthing) {
+    stuff...;
+}
+
+// Incorrect
+if (somthing)
+{
+    stuff...;
+}
+else
+{
+    stuff...;
+}
+
+// Incorrect
+if (somthing) stuff...;
+if (somthing)
+    stuff...;
+
+```
+
+### Strings
+
+- Use template strings instead of concatenation.
+
+```javascript
+// Correct
+function getStr(stuff) {
+    return "This is the ${stuff} string";
+}
+
+// Incorrect
+function wrongGetStr(stuff) {
+    return "This is the " + stuff + " string";
+}
+```
+
+## React/JSX
+
+This is an abriged version of the [Airbnb React/JSX Style Guide](https://github.com/airbnb/javascript/tree/master/react#airbnb-reactjsx-style-guide). Anything that is unclear here follow that guide. If there is a conflict, follow what is said below. 
+
+### General
+
+- Include only one React component per file.
+- Use class \<name\> extends React.Componet over React.createClass unless you need mixins
+- CapitalCamelCase with .jsx extension for component filenames.
+- Filenames should be the component name.
+
+### Alignment
+
+- Follow alignment styles shown below:
+```xml
+// Correct
+<Tag
+    propertyOne="1"
+    propertyTwo="2"
+>
+  <Child />
+</Tag>
+
+// Correct
+<Tag propertyOne="1" />
+```
+
+### Nameing
+
+- Property names use camelCase.
+- React component names use CapitalCamelCase.
+- Do not use an understore for internal methods in a react component. 
+
+```xml
+// Correct
+<ReactComponent propertyOne="value" />
+```