feat(config): add --init flag for creating the default config

README.md

@@ -107,6 +107,7 @@ git-cliff [FLAGS] [OPTIONS] [RANGE]
 
 ```
 -v, --verbose       Increases the logging verbosity
+-i, --init          Creates the default configuration file
 -l, --latest        Processes the commits starting from the latest tag
 -u, --unreleased    Processes the commits that do not belong to a tag
 -h, --help          Prints help information
@@ -134,7 +135,14 @@ git-cliff [FLAGS] [OPTIONS] [RANGE]
 
 ### Examples
 
-To simply create a changelog at your projects git root directory with a [configuration file](#configuration-file) (e.g. `cliff.toml`) present:
+The default [configuration file](#configuration-file) (`cliff.toml`) can be generated using the `--init` flag:
+
+```sh
+# create cliff.toml
+git cliff --init
+```
+
+Then simply create a changelog at your projects git root directory:
 
 ```sh
 # same as running `git-cliff --config cliff.toml --repository .`

git-cliff/src/args.rs

@@ -54,6 +54,9 @@ pub struct Opt {
 		allow_hyphen_values = true
 	)]
 	pub body:       Option<String>,
+	/// Creates the default configuration file
+	#[structopt(short, long)]
+	pub init:       bool,
 	/// Processes the commits starting from the latest tag.
 	#[structopt(short, long)]
 	pub latest:     bool,

git-cliff/src/lib.rs

@@ -17,6 +17,7 @@ use git_cliff_core::error::{
 };
 use git_cliff_core::release::Release;
 use git_cliff_core::repo::Repository;
+use git_cliff_core::DEFAULT_CONFIG;
 use std::env;
 use std::fs::{
 	self,
@@ -26,6 +27,13 @@ use std::io;
 
 /// Runs `git-cliff`.
 pub fn run(mut args: Opt) -> Result<()> {
+	// Create the configuration file if init flag is given.
+	if args.init {
+		info!("Saving the configuration file to {:?}", DEFAULT_CONFIG);
+		fs::write(DEFAULT_CONFIG, EmbeddedConfig::get_config()?)?;
+		return Ok(());
+	}
+
 	// Set the working directory.
 	if let Some(workdir) = args.workdir {
 		args.config = workdir.join(args.config);