Automatically post markdown to Slack

asblockkitbuilderurl.py

#!/usr/bin/env python3
import sys
import argparse
import json
from urllib.parse import quote


def main(argv=None):
    if argv is None:
        argv = sys.argv
    parser = argparse.ArgumentParser(description="Encode Slack block kit payloads as block kit builder URLs")
    parser.add_argument('blockkitpayloadfile', type=argparse.FileType('r'), help="file containing Block Kit Payloads. use '-' to read from stdin")
    args = parser.parse_args(argv[1:])
    blockkitpayloads = json.load(args.blockkitpayloadfile)
    for blockkitpayload in blockkitpayloads:
        blockkitpayload_txt = json.dumps(blockkitpayload)
        url = "https://app.slack.com/block-kit-builder/T02V1D15D#" + quote(blockkitpayload_txt)
        print(url)

if __name__ == '__main__':
    sys.exit(main())

asblockkitpayload.py

#!/usr/bin/env python3
import sys
import argparse
import json


def split_along_newline_by_size(file, max_length=3000):
    """Split because block kit section text fields have a max length of 3000

    https://api.slack.com/reference/block-kit/blocks#section_fields

    """
    lines = list()
    lines_len = 0
    for line in file:
        if len(line) + lines_len > max_length:
            if lines:
                yield ''.join(lines)
                lines = list()
                lines_len = 0
            else:
                raise ValueError("line exceeds max length(%d): %s" % (max_length, line))
        lines.append(line)
        lines_len += len(line)
    if lines:
        yield ''.join(lines)


def main(argv=None):
    if argv is None:
        argv = sys.argv
    parser = argparse.ArgumentParser(description="Splits mrkdwn by maxsize and encode as block kit payloads")
    parser.add_argument('mrkdwnfile', type=argparse.FileType('r'), help="file containing mrkdwn formatting text. Use '-' to read from stdin")
    parser.add_argument('-i', '--indent', type=int, default=4, help="how many spaces to indent(default: 4)")
    parser.add_argument('-m', '--maxsize', type=int, default=3000, help="maxsize of block kit payload text(default: 3000)")
    args = parser.parse_args(argv[1:])

    block_kit_payloads = list()
    for text in split_along_newline_by_size(args.mrkdwnfile, max_length=args.maxsize):

        block_kit_payload = {
            'blocks': [
                {
                    "type": "section",
                    "text": {
                        "type": "mrkdwn",
                        "text": text,
                    },
                },
            ],
        }
        block_kit_payloads.append(block_kit_payload)

    print(json.dumps(block_kit_payloads, indent=args.indent))


if __name__ == '__main__':
    sys.exit(main())

formatmarkdownforslack.sh

#!/bin/bash
MARKDOWNFILE="$1"

wget https://raw.githubusercontent.com/tubaman/pandoc-md-to-slack/tubaman/slack.lua
pandoc -t slack.lua -f markdown -i "$MARKDOWNFILE" | ./asblockkitpayload - | ./asblockkitbuilderurl  - | xargs open