Slack OAuth

Available scopes

Resource	Operation	Scope
Messaging	Send message	chat:write, users:read
Messaging	Read messages	channels:history, groups:history
Users	Get user info / list users	users:read
Channels	List channels	channels:read
Channels	Join channel	channels:join
Files	Upload file	files:write
Files	Read files	files:read
Reactions	Add/read reactions	reactions:write, reactions:read

Example — post a message

class Workflow {
  async start(data, headers, api) {
    // data IS the order object for orders/* webhook topics
    const { token } = await api.getOAuthToken('my-slack');

    await fetch('https://slack.com/api/chat.postMessage', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'Authorization': `Bearer ${token}`,
      },
      body: JSON.stringify({
        channel: '#orders',
        blocks: [
          {
            type: 'section',
            text: {
              type: 'mrkdwn',
              text: `*New order* #${data.order_number} — ${data.total_price} ${data.currency}`,
            },
          },
        ],
      }),
    });
  }
}

Example — upload a file

const formData = new FormData();
formData.append('channels', '#reports');
formData.append('content', csvString);
formData.append('filename', 'report.csv');

const { token } = await api.getOAuthToken('my-slack');
await fetch('https://slack.com/api/files.upload', {
  method: 'POST',
  headers: { Authorization: `Bearer ${token}` },
  body: formData
});