Slick (by slack-php)

A slick, single-file, dependency-free PHP micro-framework for building simple Slack apps.

For something more robust, you should use our fully-featured Slack PHP Framework.

If you are new to Slack app development, you will want to learn about it on Slack's website.

Installation

Requirements

Requires PHP 7.3+ with JSON support.

Via Composer

We recommend using Composer to install Slick, so that autoloading and keeping it up-to-date are easy.

composer require slack-php/slick

Manual

However, since Slick has no dependencies, you can directly download and require Slick.php or copy & paste the code directly into your project.

(If you do end up doing this, let me know, because I will have no other way to track that it's happening.)

Basic Usage

This small app responds to the /cool slash command by posting a message back to the conversation where the slack command was used.

Assumptions:

You have required the Composer autoloader to autoload Slick, OR you have required Slick.php directly.

You have SLACK_SIGNING_KEY set in your environment such that it is present in $_SERVER.

<?php

SlackPhp\Slick::app()
    ->route('command', '/cool', function (array $payload) {
        return "Thanks for running the `{$payload['command']}` command. You are cool! :thumbsup:";
    })
    ->run();

Want to run this example in your workspace? Check out the Example App using Docker.

Breaking It Down

Let's add some comments to that last example, so you know what is going on.

<?php

// Create the Slick app object.
SlackPhp\Slick::app()
    // Add a routable listener to the app to handle logic for a specific interaction.
    ->route(
        // The payload type (e.g., command, block_actions, view_submission, shortcut, and others).
        'command',
        // The payload ID. It's different based on the type. For commands, it is the command name.
        '/cool',
        // The listener that handles the specific interaction's logic.
        function (array $payload) {
            // Any app logic can be done here, including calling Slack's APIs.
            // Whatever you do, it should take less than 3 seconds, so you can "ack" before Slack's timeout.
        
            // Whatever is returned will be included as part of the "ack" (response) body. You can return a string, an
            // associative array, or JSON-serializable object. You should make sure that anything you include in the ack
            // is supported by the type of interaction you are responding to. Many interactions don't require an ack
            // body, so you can also return null, and empty string, or just omit a return statement, entirely.
            return "Thanks for running the `{$payload['command']}` command. You are cool! :thumbsup:";
        }
    )
    // Add as many routes as you need to handle all your interactions.
    ->route(...)
    ->route(...)
    ->route(...)
    // Runs the Slack app. This includes the following steps:
    // 1. Reads data from the current request (e.g., via $_SERVER and php://input).
    // 2. Validates the request from Slack, including verifying the request signature from the header.
    // 3. Parses the request body into an array of Slack payload data.
    // 4. Determines the payload type and ID.
    // 5. Executes one of the registered listeners based on the payload type and ID.
    // 6. Acks (responds) back to Slack.
    ->run();

Customization

There isn't much to customize, but you can control the behavior of your Slick Slack app when:

The incoming request doesn't match one of your routes (on404()).
An error occurs while processing the incoming request (orErr()).

<?php

SlackPhp\Slick::app()
    ->route(...)
    ->route(...)
    ->route(...)
    ->on404(function (array $payload) {
        // Do something custom. This is essentially used as a catch-all listener.
        // If you don't use on404(), then your app throws an error.
    })
    ->onErr(function (Throwable $err) {
        // Do something custom.
        // If you don't use onErr(), then your app calls `error_log()` and acks with a 500-level response.
    })
    ->run();

Helper Functions

If you want to do your own request handling, Slick provides some static helper methods that you can use independent from the routing features.

Slick::validateSignature(string $key, string $signature, int $time, string $body): void – Validates a Slack request signature using their v0 algorithm.
Slick::parseRequestBody(string $body): array – Parses a request body into an associative array of Slack payload data. Works for any payload type. Must provide the raw request body as a string (e.g., from php://input).
Slick::getPayloadType(array $payload): string – Determines the payload type from an array of payload data.
Slick::getPayloadId(array $payload): string – Determines the payloads routable ID from an array of payload data, based on its type.
Slack::ack(string $ack): void – Echos an "ack" response with suitable headers and status code.

slack-php/slack-php-slick