docs: add installation

docs/index.md

@@ -36,7 +36,7 @@
 
 关注 HttpRunner 的微信公众号，第一时间获得最新资讯。
 
-![](/docs/assets/qrcode.jpg)
+![](/assets/qrcode.jpg)
 
 [requests]: http://docs.python-requests.org/en/master/
 [pytest]: https://docs.pytest.org/

docs/installation.md

@@ -0,0 +1,64 @@
+
+`HttpRunner` is developed with Python, it supports Python `3.6+` and most operating systems. Combination of Python `3.6/3.7/3.8` and `macOS/Linux/Windows` are tested continuously on [GitHub-Actions][github-actions].
+
+## Installation
+
+`HttpRunner` is available on [`PyPI`][PyPI] and can be installed through `pip`.
+
+```bash
+$ pip install httprunner
+```
+
+If you want to keep up with the latest version, you can install with github repository url.
+
+```bash
+$ pip install git+https://github.com/httprunner/httprunner.git@master
+```
+
+If you have installed `HttpRunner` before and want to upgrade to the latest version, you can use the `-U` option.
+
+```bash
+$ pip install -U httprunner
+$ pip install -U git+https://github.com/httprunner/httprunner.git@master
+```
+
+## Check Installation
+
+When HttpRunner is installed, 4 commands will be added in your system.
+
+- `httprunner`: main command, used for all functions
+- `hrun`: alias for `httprunner run`, used to run YAML/JSON testcases
+- `hmake`: alias for `httprunner make`, used to convert YAML/JSON testcases to pytest files
+- `har2case`: alias for `httprunner har2case`, used to convert HAR to YAML/JSON testcases
+
+To see `HttpRunner` version:
+
+```text
+$ httprunner -V
+3.0.6
+```
+
+To see available options, run:
+
+```text
+$ httprunner -h
+usage: httprunner [-h] [-V] {run,startproject,har2case,make} ...
+
+One-stop solution for HTTP(S) testing.
+
+positional arguments:
+  {run,startproject,har2case,make}
+                        sub-command help
+    run                 Make HttpRunner testcases and run with pytest.
+    startproject        Create a new project with template structure.
+    har2case            Convert HAR(HTTP Archive) to YAML/JSON testcases for
+                        HttpRunner.
+    make                Convert YAML/JSON testcases to pytest cases.
+
+optional arguments:
+  -h, --help            show this help message and exit
+  -V, --version         show version
+```
+
+[PyPI]: https://pypi.python.org/pypi
+[github-actions]: https://github.com/httprunner/httprunner/actions