# README

StreamingFast CLI Library

Quick and opinionated library aiming to create CLI application rapidly. The library contains CLI primitives (around Cobra/Viper) as well as low-level primitives to ease the creation of developer scripts.

Note This library is experimental and the API could change without notice.

Example

The folder ./example contains example usage of the library. You can run them easily them, open a terminal and navigate in the example folder, then go run ...

Flat - go run ./flat
Nested - go run ./nested

Public Helpers

Method	Description
`cli.NoError(err, "file not found %q", fileName)`	Exit the process with exit code 1 and prints `fmt.Printf("file not found %q: %w\n", fileName, err)` if `err != nil`
`cli.Ensure(x == 0, "x point should be 0, got %d", x)`	Exit the process with exit code 1 and prints `fmt.Printf("x point should be 0, got %d\n", x)` if condition received is `false`
`cli.Quit("current date %d is too far away", time.Now())`	Exit the process with exit code 1 and prints `fmt.Printf("x point should be 0, got %d\n", x)`
`cli.FileExists("./some/file.png")`	Returns `true` if the file received in argument exists, `false` otherwise
`cli.CopyFile("current date %d is too far away", time.Now())`	Exit the process with exit code 1 and prints `fmt.Printf("x point should be 0, got %d\n", x)`
-	-

Sample Boilerplate (copy/paste ready)

package main

import (
	"fmt"
	"os"

	. "github.com/streamingfast/cli"
	"github.com/streamingfast/logging"
	"github.com/spf13/cobra"
	"go.uber.org/zap"
)

var zlog = zap.NewNop()
var tracer = logging.ApplicationLogger("nested", "github.com/acme/nested", &zlog)

func main() {
	Run("runner", "Some random command runner with 2 sub-commands",
		Command(generateE,
			"generate",
			"Quick command summary, without a description",
		),
		Command(compareE,
			"compare <input_file>",
			"Quick command summary, with a description, the actual usage above is descriptive, you must handle the arguments manually",
			Description(`
				Description of the command, automatically de-indented by using first line identation,
				use 'go run ./example/nested compare --help' to see it in action!
			`),
			ExamplePrefixed("runner", `
				compare relative_file.json
				compare /absolute/file.json
			`),
		),
	)
}

func generateE(cmd *cobra.Command, args []string) error {
	_, err := os.Getwd()
	NoError(err, "unable to get working directory")

	fmt.Println("Generating something")
	return nil
}

func compareE(cmd *cobra.Command, args []string) error {
	shouldContinue, wasAnswered := AskConfirmation(`Do you want to continue?`)
	if wasAnswered && shouldContinue {

	} else {
		fmt.Println("Not showing diff between files, run the following command to see it manually:")
	}

	return nil
}

Contributing

Issues and PR in this repo related strictly to the cli library.

Report any protocol-specific issues in their respective repositories

Please first refer to the general StreamingFast contribution guide, if you wish to contribute to this codebase.

This codebase uses unit tests extensively, please write and run tests.