update README.md

README.md

@@ -2,12 +2,70 @@
 
 Simple CLI tool that allows to pretty print all dependencies within conda environment.
 
+## Installation
+
+`conda-leaves` doesn't require any additional libraries to be installed, but it assumes user has `conda` and `cargo` installed and available in system's path.
+
+Installation is as simple as running `cargo install conda-leaves`.
+
+## Commands
+
+### `help`
+
+Prints help information.
+
+```bash
+conda-leaves help
+```
+
+### `leaves`
+
+Prints top level packages in conda environment.
+
+Flags:
+
+- `--no-pip` - Prints packages installed by conda only
+
+Usage:
+
+```bash
+conda-leaves leaves [Flags]
+```
+
+### `package`
+
+Prints tree view for the package.
+
+Options:
+
+- `-n`, `-name` - Name of the package that should be printed.
+
+Usage:
+
+```bash
+conda-leaves package --name <name>
+```
+
+### `export`
+
+Exports leaves to the file.
+
+Options:
+
+- `-f`, `--filename` (default: environment.yml) - Name of the output yml file.
+
+Usage:
+
+```bash
+conda-leaves export [Options]
+```
+
 ## Development
 
-### Running main using test data
+### Running CLI using test data
 
 ```bash
-CONDA_PREFIX="./tests/data" cargo run --release
+CONDA_PREFIX="./tests/data" cargo run --release -- <command>
 ```
 
 ### Running tests

src/main.rs

@@ -29,6 +29,7 @@ enum Opts {
     },
     /// Exports leaves to the file
     Export {
+        /// Name of the output yml file
         #[structopt(
             short = "f",
             long,
@@ -50,7 +51,7 @@ fn main() -> io::Result<()> {
             }
             Err(e) => {
                 eprintln!("{}", e);
-                std::process::exit(1)
+                std::process::exit(404)
             }
         },
         Opts::Leaves { no_pip } => match no_pip {
@@ -61,7 +62,10 @@ fn main() -> io::Result<()> {
                 }
             }
             // FIXME for now we support conda only
-            true => println!("Mixed conda-pip environments are not supported yet."),
+            true => {
+                eprintln!("Mixed conda-pip environments are not supported yet.");
+                std::process::exit(1)
+            }
         },
         Opts::Export { filename } => {
             let leaves = get_leaves();