OpenAI ChatGPT: Chat

const MAX_TOKENS_DEFAULT = 2048;
const MAX_IMAGE_SIZE = 20971520; // ChatGPT の制限。1 ファイルにつき 20 MB まで
const AVAILABLE_IMAGE_TYPES = ['image/jpeg', 'image/png', 'image/gif', 'image/webp'];

function main() {
    ////// == 工程コンフィグ・ワークフローデータの参照 / Config & Data Retrieving ==
    const auth = configs.getObject('conf_Auth');   /// REQUIRED
    const organizationId = configs.get('conf_OrganizationId');
    const model = configs.get('conf_Model');
    const maxTokens = retrieveMaxTokens();
    const reasoningEffort = retrieveSelectItem('conf_ReasoningEffort');
    const verbosity = retrieveSelectItem('conf_Verbosity');
    const temperature = retrieveTemperature();
    const stopSequences = retrieveStopSequences();

    // https://platform.openai.com/docs/guides/safety-best-practices
    // Sending end-user IDs in your requests can be a useful tool to help OpenAI monitor and detect abuse.
    const requestUser = `m${processInstance.getProcessModelInfoId().toString()}`;

    const gptRole = configs.get('conf_GPT_Role');    // NotRequired
    const message1 = configs.get('conf_Message1');    /// REQUIRED
    if (message1 === '') {
        throw new Error('User Message is empty.');
    }
    const imageUrls1 = retrieveImageUrls('conf_Images1');
    const imageDetail1 = retrieveSelectItem('conf_Images1Detail');

    ////// == 演算 / Calculating ==
    const answer1 = createChat(auth, organizationId, model, maxTokens, reasoningEffort, verbosity, temperature, stopSequences, requestUser, gptRole, message1, imageUrls1, imageDetail1);

    ////// == ワークフローデータへの代入 / Data Updating ==
    saveData('conf_Answer1', answer1 ?? '');
}

/**
 * SELECT_ITEM の設定値を取得する
 * 空の場合、undefined を返す
 * @param configName
 * @returns {undefined|String}
 */
const retrieveSelectItem = (configName) => {
    const value = configs.get(configName);
    if (value === '') {
        return undefined;
    }
    return value;
};

/**
 * config から、max_completion_tokens として設定する最大トークン数を読み出す
 * max_tokens は Deprecated
 * 指定なしの場合は 2048 を返す
 * @returns {Number}
 */
const retrieveMaxTokens = () => {
    const maxTokens = configs.get('conf_MaxTokens');
    if (maxTokens === '') {
        return MAX_TOKENS_DEFAULT;
    }
    const regExp = new RegExp(/^[1-9][0-9]*$/);
    if (!regExp.test(maxTokens)) {
        throw new Error('Maximum number of tokens must be a positive integer.');
    }
    return parseInt(maxTokens, 10);
};

/**
 * config から温度を読み出す
 * 指定なしの場合、1 を返す
 * @returns {Number}
 */
const retrieveTemperature = () => {
    const temperature = configs.get('conf_Temperature');
    if (temperature === '') {
        return 1;
    }
    const regExp = /^([0-1](\.\d+)?|2(\.0+)?)$/;
    if (!regExp.test(temperature)) {
        throw new Error('Temperature must be a number from 0 to 2.');
    }
    return parseFloat(temperature);
};

const MAX_STOP_SEQUENCE_NUM = 4;

/**
 * config から停止シーケンスを読み出す
 * @returns {Array<String>}
 */
const retrieveStopSequences = () => {
    const stopSequencesStr = configs.get('conf_StopSequences');
    if (stopSequencesStr === '') {
        return [];
    }
    const stopSequences = stopSequencesStr.split('\n')
        .filter(s => s !== '');
    if (stopSequences.length > MAX_STOP_SEQUENCE_NUM) {
        throw new Error(`Too many stop sequences. The maximum number is ${MAX_STOP_SEQUENCE_NUM}.`);
    }
    return stopSequences;
};

/**
 * config から添付画像を読み出し、image_url パラメータに設定する文字列の配列として返す
 * @param configName
 * @returns {Array<String>} imageUrls
 */
const retrieveImageUrls = (configName) => {
    const imagesDef = configs.getObject(configName);
    if (imagesDef === null) {
        return [];
    }
    const images = engine.findData(imagesDef);
    if (images === null) {
        return [];
    }
    const imageUrls = [];
    images.forEach(image => {
        if (image.getLength() > MAX_IMAGE_SIZE) {
            throw new Error(`Attached image "${image.getName()}" is too large. Each file must be less than ${MAX_IMAGE_SIZE} bytes.`);
        }
        const contentType = image.getContentType();
        if (!AVAILABLE_IMAGE_TYPES.includes(contentType)) {
            throw new Error(`Content-Type of "${image.getName()}" is not supported. Supported types are: ${AVAILABLE_IMAGE_TYPES.join(', ')}.`);
        }
        imageUrls.push(`data:${contentType};base64,${base64.encodeToString(fileRepository.readFile(image))}`);
    });
    return imageUrls;
};

/**
 * チャットの実行
 * @param auth
 * @param organizationId
 * @param model
 * @param maxTokens
 * @param reasoningEffort
 * @param verbosity
 * @param temperature
 * @param stopSequences
 * @param requestUser
 * @param gptRole
 * @param message1
 * @param imageUrls1
 * @param imageDetail1
 * @returns {String} answer1
 */
const createChat = (auth, organizationId, model, maxTokens, reasoningEffort, verbosity, temperature, stopSequences, requestUser, gptRole, message1, imageUrls1, imageDetail1) => {
    //// OpenAI API > Documentation > API REFERENCE > CHAT
    //// https://platform.openai.com/docs/api-reference/chat

    /// prepare json
    const requestJson = {
        safety_identifier: requestUser,
        model,
        n: 1,
        max_completion_tokens: maxTokens,
        reasoning_effort: reasoningEffort,
        verbosity,
        temperature,
        messages: []
    };
    if (gptRole !== '') {
        requestJson.messages.push({
            role: 'system',
            content: gptRole
        });
    }
    if (stopSequences.length > 0) { // モデルによっては、空配列をセットするとエラーになる
        requestJson.stop = stopSequences;
    }
    const message1Content = [];
    message1Content.push({
        type: 'text',
        text: message1
    });
    imageUrls1.forEach(imageUrl => {
        const imageObj = {
            type: 'image_url',
            image_url: {
                url: imageUrl
            }
        };
        imageObj.image_url.detail = imageDetail1;
        message1Content.push(imageObj);
    });
    requestJson.messages.push({
        role: 'user',
        content: message1Content
    });

    let request = httpClient.begin().authSetting(auth)
        .body(JSON.stringify(requestJson), 'application/json');
    if (organizationId !== null && organizationId !== '') {
        request = request.header('OpenAI-Organization', organizationId);
    }
    const response = request.post('https://api.openai.com/v1/chat/completions');

    const responseCode = response.getStatusCode();
    const responseBody = response.getResponseAsString();
    if (responseCode !== 200) {
        engine.log(responseBody);
        throw new Error(`Failed to request. status: ${responseCode}`);
    }
    const {choices, usage} = JSON.parse(responseBody);
    const finishReason = choices[0].finish_reason;
    const answer1 = choices[0].message.content;
    engine.log(`Finish Reason: ${finishReason}`);
    engine.log(`Prompt Tokens: ${usage.prompt_tokens}`);
    engine.log(`Completion Tokens: ${usage.completion_tokens}`);
    engine.log(`Completion Tokens Details: ${JSON.stringify(usage.completion_tokens_details)}`);
    if (answer1 === undefined || answer1 === null || answer1 === '') {
        throw new Error(`No response content generated. Finish Reason: ${finishReason}`);
    }
    return answer1;
};

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