The selected agency must have permissions to access API Gateway, Image Moderation, and OBS resources. For details on how to create an agency, see Creating an Agency.

const https = require('https');
const fs = require('fs');
const ObsClient = require('esdk-obs-nodejs');    //References an OBS SDK.
let PAYLOAD = {};
let CONTEXT = null;
const PATH = '/tmp/image.png'
exports.handler = function (event, context, callback) {
    CONTEXT = context;
    
    //Cross-origin verification
    if (event.httpMethod === "OPTIONS") {
        console.log('OPTIONS request, pass.');
        const result = {
            body: '',
            headers: {
                "Content-Type":"application/json",
                "Access-Control-Allow-Origin": "*",
                "Access-Control-Allow-Headers": "Content-Type,Accept",
                "Access-Control-Allow-Methods": "GET,POST,PUT,DELETE"
            },
            statusCode: 200,
            isBase64Encoded: false
        };
        callback(null, result);
        return;
    }
    
    new Promise(function(resolve, reject) {
        var token = context.getToken();
        const options = {
            hostname: 'moderation.cn-north-1.myhuaweicloud.com',
            port: 443,
            path: '/v1.0/moderation/image',
            method: 'POST',
            headers: {
                'Content-Type': 'application/json;charset=utf8',
                'X-Auth-Token': token
            }
        };
        PAYLOAD = constructPayload(event);
        console.log("Sending request to AIS...")
        const req = https.request(options, (res) => {
            var status = res.statusCode
            console.log("status:",  status)
            res.on('data', (d) => {
                resolve(d.toString());
            });
        });

        req.on('error', (e) => {
            console.error(e);
        });
        req.write(JSON.stringify(PAYLOAD));
        req.end();
    }).then(function(value) {
        // check image and save if porn
        const resultObj = JSON.parse(value);
        const bucket = context.getUserData('BUCKET');

        const apigBody = {
          result: resultObj.result.detail.porn,
          suggestion: resultObj.result.suggestion,
          eiInfo: resultObj.result,
        };
        saveImage(PAYLOAD.image, resultObj.suggestion || '', bucket).then((err) => {
            // return apig result
            const result = {
                body: JSON.stringify(apigBody),
                headers: {
                    "Content-Type":"application/json",
                    "Access-Control-Allow-Origin": "*",
                    "Access-Control-Allow-Headers": "Content-Type,Accept",
                    "Access-Control-Allow-Methods": "GET,POST,PUT,DELETE"
                },
                statusCode: 200,
                isBase64Encoded: false
            };
            callback(null, result);
        });
    });	
}
function constructPayload(event) {
    if (event.httpMethod != "POST") {
        return {
            "image": "",
            "url": "https://bjbucket.obs.myhuaweicloud.com/70923411.jpg",//Example URL. Replace it with the actual URL.
            "categories": [
                "porn"
            ],
            "threshold" : ""
        }
    }
    const bodyStr = new Buffer(event.body, 'base64').toString('ascii');
    const body = JSON.parse(bodyStr);
    if (body.url != null && body.url.trim() != "") {
        return {
            "image": "",
            "url": body.url,
            "categories": [
                "porn"
            ],
            "threshold" : ""
        }
    } else {
        return {
            "image": body.image,
            "url": "",
            "categories": [
                "porn"
            ],
            "threshold" : ""
        };
    }
}

function saveImage(image, imageInfo, bucket) {
    return new Promise((resolve, reject) => {
        if (/*imageInfo !== 'pass'*/false) {
            console.log('>>>>>>>not pass, start save image');
            writeImage(image).then((err) => {
                if (!err) {
                    uploadImage(PATH, bucket).then((err) => {
                        resolve(err);
                    });
                } else {
                    resolve(err)
                }
            });
        } else {
            resolve(null);
        }
    });
}


function writeImage(image) {
    return new Promise((resolve, reject) => {
        const imageBuffer = new Buffer(image, 'base64');
        fs.writeFile(PATH, imageBuffer, function(err) {
            console.log('>>>>>>>>>>write file:', err);
            resolve(err);
        }); 
    });
}

function uploadImage(path, bucket) {
    return new Promise((resolve, reject) => {
        // upload path to bucket;
        const client = buildOBSClient(CONTEXT);
        client.putObject({
            Bucket: bucket,
            Key: `image-${(new Date()).valueOf()}.png`,
            SourceFile: path
        }, (err, result) => {
            if (err) {
                console.error('Upload Error-->' + err);
            } else {
                console.log('Upload Status-->' + result.CommonMsg.Status + '. uploading file OK!');
            }
            resolve(err);
        });
    });
}

function buildOBSClient(context) {
    // Obtains a temporary AK and SK to access OBS. An agency is required to access IAM.
    const my_access_key = context.getAccessKey();
    const my_secret_access_key = context.getSecretKey();
    console.log('begin create obs client!');
    return new ObsClient({
        access_key_id: my_access_key,
        secret_access_key: my_secret_access_key,
        server: 'obs.cn-north-1.myhuaweicloud.com'//Example. Replace it with the actual value.
    });
}