Update README

README.md

@@ -3,3 +3,102 @@
 ![crates.io](https://img.shields.io/crates/v/bashtestmd)
 
 Compiles Markdown files with Bash code blocks into a single Bash script for CI testing purposes.
+
+## Basic Usage
+
+The following command parses all code blocks from the input markdown file and generates a script
+containing all blocks tagged with the specified `TAG_NAME`
+
+```sh
+bashtestmd --input {PATH_TO_INPUT_FILE} --output {OUTPUT_FILE_NAME} --tag {TAG_NAME}`.
+```
+
+For example, `bashtestmd --input README.md --output demo-readme.sh --tag test-ci` will find all code blocks
+of the form and generate a script which runs them sequentially, enforcing that each command exits with status code `0`.
+
+````
+```sh,test-ci
+$ echo "This is a demo"
+```
+````
+
+Note that `bashtestmd` only interprets lines beginning with `$` as commands. This allows output to be included in
+snippets without compromising the generated script.
+
+````
+```sh,test-ci
+$ echo "This is a demo"
+This is a demo
+```
+````
+
+## Supported tags
+
+`bashtestmd` supports the following optional tags on code blocks:
+
+1. `bashtestmd:compare-output`
+1. `bashtestmd:exit-code-ignore`
+1. `bashtestmd:exit-code="{EXPECTED_CODE}"`
+1. `bashtestmd:long-running`
+1. `bashtestmd:wait-until="{TEXT}"`
+
+### Compare Output
+
+The tag `bashtestmd:compare-output` causes the generated script to check that the command output
+matches the output in the markdown file.
+
+For example, this command will fail if the server returns `"goodbye"` in response to a query to `localhost:80/hello`
+instead of the expected `"hello, world"`
+
+````
+```sh,test-ci,bashtestmd:compare-output`
+$ curl localhost:80/hello
+"hello, world"
+```
+````
+
+### Exit Code Ignore
+
+The tag `bashtestmd:exit-code-ignore` causes `bashtestmd` to ignore the exit code of the command rather than enforcing that the code is `0`
+
+### Exit Code
+
+The tag `bashtestmd:exit-code="{CODE}"` causes `bashtestmd` to check that the exit code of the command matches the provided value
+
+````
+```sh,test-ci,bashtestmd:exit-code="1"`
+$ rm this_file_does_not_exist.txt
+rm: this_file_does_not_exist.txt: No such file or directory
+```
+````
+
+### Long Running
+
+The tag `bashtestmd:long-running` causes the command to run in the background and waits 120 seconds for the task to complete.
+It is strongly recommended to combine `long-running` with `wait-until` in order to override this default behavior.
+
+For example, the following commmand compiles to `cargo run &; sleep 120`
+
+````
+```sh,test-ci,bashtestmd:long-running`
+$ cargo run
+```
+````
+
+### Wait Until
+
+The tag `bashtestmd:wait-until={SOME_TEXT}` will cause the script to wait for the process to output the expected text
+before continuing rather than simply sleeping for two minutes. Note that this command **_requires_** the `long-running` tag in order to have an effect.
+
+````
+```sh,test-ci,bashtestmd:long-running,bashtestmd:wait-until="Finished release"`
+$ cargo build --release
+```
+````
+
+## Local Installation
+
+To set up `bashtestmd` for local development
+
+1. `git clone https://github.com/Sovereign-Labs/bashtestmd.git`
+1. `cargo install --path bashtestmd/`