Microsoft Teams: Post to Channel

// OAuth2 config sample at [OAuth 2.0 Setting]
// - Authorization Endpoint URL: https://login.microsoftonline.com/organizations/oauth2/v2.0/authorize
// - Token Endpoint URL: https://login.microsoftonline.com/organizations/oauth2/v2.0/token
// - Scope: ChannnelMessage.Send offline_access
// - Consumer Key: (Get by Microsoft Azure Active Directory)
// - Consumer Secret: (Get by Microsoft Azure Active Directory)

const GRAPH_URI = 'https://graph.microsoft.com/v1.0/';

const main = () => {
    //// == 工程コンフィグの参照 / Config Retrieving ==
    const oauth2 = configs.getObject('conf_OAuth2');
    const targetUrl = retrieveTargetUrl();
    const subject = configs.get('conf_Subject');
    const markdownText = configs.get('conf_Markdown') ?? '';
    if (markdownText === '') {
        throw new Error('Post Content is empty.');
    }

    //// == 演算 / Calculating ==
    const {teamId, channelId, messageId} = parseTargetUrl(targetUrl);
    const postUrl = post(oauth2, teamId, channelId, messageId, subject, markdownText);

    //// == ワークフローデータへの代入 / Data Updating ==
    saveData('conf_PostUrl', postUrl);
};

/**
 * config から投稿先 URL を読み出す
 * 空の場合はエラー
 * @returns {String}
 */
const retrieveTargetUrl = () => {
    let targetUrl = configs.get('conf_TargetUrl');
    const def = configs.getObject('conf_TargetUrl');
    if (def !== null) {
        targetUrl = engine.findData(def);
    }
    if (targetUrl === null || targetUrl === '') {
        throw new Error('Target URL is empty.');
    }
    return targetUrl;
};

/**
 * 投稿先の URL をパースし、teamId, channelId, messageId を返す
 * チャンネル URL: https://{domain}/{path}/channel/{channelId}/{channelName}?groupId={teamId}&tenantId={tenantId}
 * チャンネルメッセージ URL: https://{domain}/{path}/message/{channelId}/{messageId}?...&groupId={teamId}&...
 * @param {String} targetUrl
 * @returns {Object} teamId, channelId, messageId
 */
const parseTargetUrl = (targetUrl) => {
    const [pathPart, queryPart] = targetUrl.split('?');
    const pathSegments = pathPart.split('/');
    const queryParams = parseQueryParams(queryPart);

    // メッセージ URL の判定
    const messageIndex = pathSegments.indexOf('message');
    if (messageIndex !== -1 && messageIndex + 2 < pathSegments.length) {
        const channelId = decodeURIComponent(pathSegments[messageIndex + 1]);
        const messageId = decodeURIComponent(pathSegments[messageIndex + 2]);
        const teamId = queryParams.groupId;
        if (teamId === undefined) {
            throw new Error(`groupId not found in target URL: ${targetUrl}`);
        }
        engine.log(`teamId: ${teamId}, channelId: ${channelId}, messageId: ${messageId}`);
        return { teamId, channelId, messageId };
    }

    // チャンネル URL の判定
    const channelIndex = pathSegments.indexOf('channel');
    if (channelIndex === -1 || channelIndex + 1 >= pathSegments.length) {
        throw new Error(`Invalid Target URL: ${targetUrl}`);
    }
    const channelId = decodeURIComponent(pathSegments[channelIndex + 1]);
    const teamId = queryParams.groupId;
    if (teamId === undefined) {
        throw new Error(`groupId not found in target URL: ${targetUrl}`);
    }
    engine.log(`teamId: ${teamId}, channelId: ${channelId}`);
    return { teamId, channelId, messageId: null };
};

/**
 * クエリ文字列をパースしてオブジェクトにする
 * @param {String|undefined} queryPart
 * @returns {Object}
 */
const parseQueryParams = (queryPart) => {
    if (queryPart === undefined) {
        return {};
    }
    const params = {};
    queryPart.split('&').forEach(param => {
        const [key, ...rest] = param.split('=');
        params[key] = rest.join('='); // value に = が含まれる場合を考慮
    });
    return params;
};

/**
 * メッセージを投稿する
 * @param {AuthSettingWrapper} oauth2  OAuth2 設定情報
 * @param {String} teamId
 * @param {String} channelId
 * @param {String|null} messageId
 * @param {Strung} subject
 * @param {String} markdownText
 * @returns {String} 投稿したメッセージの URL
 */
const post = (oauth2, teamId, channelId, messageId, subject, markdownText) => {
    let url;
    if (messageId !== null) { // チャンネルメッセージへの返信
        url = `${GRAPH_URI}teams/${encodeURIComponent(teamId)}/channels/${encodeURIComponent(channelId)}/messages/${encodeURIComponent(messageId)}/replies`;
    } else { // チャンネルへの投稿
        url = `${GRAPH_URI}teams/${encodeURIComponent(teamId)}/channels/${encodeURIComponent(channelId)}/messages`;
    }
    const reqBody = {
        body: {
            contentType: 'html',
            content: markdown.toHtml(markdownText)
        }
    };
    if (subject !== '' && messageId === null) {
        reqBody.subject = subject;
    }
    const response = httpClient.begin()
        .authSetting(oauth2)
        .body(JSON.stringify(reqBody), 'application/json; charset=UTF-8')
        .post(url);
    const status = response.getStatusCode();
    const responseStr = response.getResponseAsString();
    if (status !== 201) {
        engine.log(responseStr);
        throw new Error(`Failed to post message. status: ${status}`);
    }
    return JSON.parse(responseStr).webUrl;
};

/**
 * データ項目への保存
 * @param {String} configName
 * @param {*} data
 */
const saveData = (configName, data) => {
    const def = configs.getObject(configName);
    if (def === null) {
        return;
    }
    engine.setData(def, data);
};