slack-messaging 0.7.4

Support building Slack Block Kit message
Documentation
# Slack Messaging

[![Version](https://img.shields.io/crates/v/slack-messaging)](https://crates.io/crates/slack-messaging)
[![License](https://img.shields.io/crates/l/slack-messaging)](https://github.com/kaicoh/slack-messaging/blob/main/LICENSE)
[![Test](https://img.shields.io/github/actions/workflow/status/kaicoh/slack-messaging/test.yml)](https://github.com/kaicoh/slack-messaging/actions/workflows/test.yml)

This is a library for [Rust](https://www.rust-lang.org/) to support building [Slack Block Kit messages](https://docs.slack.dev/reference/block-kit).
Using this, you can build any messages in type-safe way like following.

```rust
use slack_messaging::{mrkdwn, plain_text, Message};
use slack_messaging::blocks::{elements::Button, Actions, Section};
use std::error::Error;

#[tokio::main]
async fn main() -> Result<(), Box<dyn Error>> {
    let message = Message::builder()
        .block(
            Section::builder()
                .text(mrkdwn!("You have a new request:\n*<fakeLink.toEmployeeProfile.com|Fred Enriquez - New device request>*")?)
                .build()?
        )
        .block(
            Section::builder()
                .field(mrkdwn!("*Type:*\nComputer (laptop)")?)
                .field(mrkdwn!("*When:*\nSubmitted Aug 10")?)
                .build()?
        )
        .block(
            Actions::builder()
                .element(
                    Button::builder()
                        .text(plain_text!("Approve")?)
                        .value("approve")
                        .primary()
                        .build()?
                )
                .element(
                    Button::builder()
                        .text(plain_text!("Deny")?)
                        .value("deny")
                        .danger()
                        .build()?
                )
                .build()?
        )
        .build()?;

    let req = reqwest::Client::new()
        .post("https://hooks.slack.com/services/T00000000/B00000000/XXXXXXXXXXXXXXXXXXXXXXXX")
        .json(&message);

    if let Err(err) = req.send().await {
        eprintln!("{err}");
    }

    Ok(())
}
```

The message payload of the above example is following.

```json
{
    "blocks": [
        {
            "type": "section",
            "text": {
                "type": "mrkdwn",
                "text": "You have a new request:\n*<fakeLink.toEmployeeProfile.com|Fred Enriquez - New device request>*"
            }
        },
        {
            "type": "section",
            "fields": [
                {
                    "type": "mrkdwn",
                    "text": "*Type:*\nComputer (laptop)"
                },
                {
                    "type": "mrkdwn",
                    "text": "*When:*\nSubmitted Aug 10"
                }
            ]
        },
        {
            "type": "actions",
            "elements": [
                {
                    "type": "button",
                    "text": {
                        "type": "plain_text",
                        "text": "Approve"
                    },
                    "value": "approve",
                    "style": "primary"
                },
                {
                    "type": "button",
                    "text": {
                        "type": "plain_text",
                        "text": "Deny"
                    },
                    "value": "deny",
                    "style": "danger"
                }
            ]
        }
    ]
}
```

## License

This software is released under the [MIT License](https://github.com/kaicoh/slack-messaging/blob/main/LICENSE).