What does DCli do?
DCli has a singular focus:
make it easy to build command line apps using the Dart programming language.
DCli has the following aims:
- make building CLI apps as easy as walking.
- fully utilise the expressiveness of Dart.
- works seamlessly with the core Dart libraries.
- provide a cross platform API for Windows, OSx and Linux.
- create a completely synchronously API (no futures and no async).
- call any CLI app.
- make debugging CLI apps easy.
- generate error messages that make it easy to resolve problems.
- provide quality documentation and examples.
Asking the user to input data into a CLI application should be simple. DCli provide a number of functions to facilitate user input.
- ask
- confirm
- menu
import 'package:dcli/dcli.dart';
void main(){
var username = ask('Username:', validator: Ask.required);
if (confirm('Are you over 18')) {
print(orange('Welcome to the club'));
}
var selected = menu('Select your poision', options: ['beer', 'wine', 'spirits']
defaultOption: 'beer');
print(green('You choice was: $selected'));
}
DCli provide an extensive API designed specifically for building command line apps.
Out of the box dart provides the basic 'print' statement which DCli extends to provide common features.
- print
- printerr - prints to stderr.
- colour coding
- cursor management
- clear screen/clear line
print(orange("I'm an important message"));
printerr(red('Oops, something went wrong here'));
A fundamental task of most CLI applications is the management of files and directories. DCli provides a large set of tools for file management such as:
- find
- which
- copy
- copyTree
- move
- moveTree
- delete
- deleteDir
- touch
- exists
- isWritable/isReadable/isExecutable
- isFile
- isLink
- isDirectory
- lastModified
import 'package:dcli/dcli.dart';
void main() {
if (!exists('/keep')) {
createDir('/keep');
}
var images = find('*.png', root: '/images');
for (var image in images) {
if (image.startsWith('nsfw')) {
copy(image, '/keep');
}
}
}
You are often going to need to read/write and modify text and binary files.
- read
- write
- truncate
- append
- replace
- tail
- cat
You still have full access to the full set of Dart APIs
// write lines to myfile.ini
var settings = 'myfile.ini';
settings.write('[section1]');
settings.append('color=red');
settings.append('color=blue');
// fix the spelling in myfile.ini
replace(settings, 'color', 'colour');
A core feature of DCli is the ability to call other CLI apps and process their output.
- run
- start
- toList
- forEach
- firstLine
- lastLine
- | (pipe)
- stream
Run mysql with all output being displayed to the console.
var user = ask('username');
var password = ask('password', hidden:true);
'mysql -u $user --password=$password customerdb -e "select 1"'.run;
Run a mysql command and store the results in a list (users).
var users = 'mysql customerdb -e "select fname, sname from user"'
.toList(skipLines: 1);
/// now parse each user and print their name
for (var user in users) {
var parts = user.split(',');
print('Firstname: ${parts[0]} Surname: ${parts[1]});
}
/// Run grep and print each line that it finds
'grep error /var/lib/syslog'.forEach((line) => print(line));
DCli makes it easy to explore your environment with direct manipulation of environment variables.
var user = env['USER'];
env['JAVA_HOME'] = '/usr/lib/java';
PATH management tools:
Env().appendToPath('/home/me/bin');
Env().addToPATHIfAbsent('/home/me/bin');
Env().removeFromPATH('/home/me/bin');
And the ability to explore the Dart environment.
/// Get details of the current dart script that is running.
Script.current;
DartSdk().pathToDartExe;
PubCache().pathTo
Last modified 10mo ago