Cesium learning notes (II) uploading data using rest API

Step1. Provide ion information about your data

Use the data files provided on the official website ：Reichstag.zip
To create a new asset, we POST information about our data and what we want to do with it to the /v1/assets endpoint. The POST body looks like this:

const postBody = {
    
    name: 'Reichstag',
    description: 'See [Wikipedia](https://en.wikipedia.org/?curid=217577).',
    type: '3DTILES',
    options: {
    
        sourceType: 'CITYGML',
        clampToTerrain: true,
        baseTerrainId: 1
    }
}

• name Is a non empty string
• description It's a Markdown Compatible string
• type Is one of three types ：3DTILES、IMAGERY、TERRAIN, Now uploading CityGML, It can only be used to generate 3DTILES
• options yes the ion tilling pipeline The option to , And specific to the type of data being uploaded . In this example, specify ：
  • sourceType Indicates that we are uploading CityGML data
  • clampToTerrain tell pipeline, We want it to adjust the height of the buildings in the file so that they are placed on the ground
  • baseTerrainID To specify a terrain asset id As the ground . In the code above ,“1” representative CesiumWorldTerrain. If not defined and clamoToTerrain = true, Then the building will be put into WGS84 Ellipsoid .

To actually create assets , We use the following code to publish the above objects ：

const response = await request({
    
    url: 'https://api.cesium.com/v1/assets',
    method: 'POST',
    headers: {
     Authorization: `Bearer ${
      accessToken}` },
    json: true,
    body: postBody
});

This service returns response It has three properties ：

• response.uploadLocation Provide temporary vouchers and location information , Used to upload source data to ion, The credentials last about 1 Hours .
• response.onComplete It contains the information that we will use to send back to the server after uploading the data .
• response.assetMetadata Include this asset All the information about it, including its id、 state , And the name and description we just released .
  This response as follows ：

{
    
  "assetMetadata": {
    
    "id": 21111,
    "type": "3DTILES",
    "name": "Reichstag",
    "description": "See [Wikipedia](https://en.wikipedia.org/?curid=217577).",
    "attribution": "",
    "bytes": 0,
    "dateAdded": "2019-04-19T00:30:54.111Z",
    "status": "AWAITING_FILES",
    "percentComplete": 0
  },
  "uploadLocation": {
    
    "bucket": "assets.cesium.com",
    "prefix": "sources/21111/",
    "accessKey": "ASIATXRQLSFCKKLAIVXW",
    "secretAccessKey": "Qa6YC2yq78hoCR4KYF4atHEnytfgLJMNV0KPdpw8",
    "sessionToken": "FQoGZXIvYXdzEIr//wEaDIEDvhx6N7x4..."
  },
  "onComplete": {
    
    "method": "POST",
    "url": "https://api.cesium.com/v1/assets/21111/uploadComplete",
    "fields": {
    }
  }
}

Step 2.Upload your data to the provided Amazon S3 bucket

We can use anything with S3 Compatible libraries to perform Uploads , However, we recommend using official services that are widely available in multiple languages AWS Development kit . Everything we need is response.uploadLocation In the object .
Every asset Of S3 API Initialization is the same ：

const AWS = require('aws-sdk');
const uploadLocation = response.uploadLocation;

const s3 = new AWS.S3({
    
    apiVersion: '2006-03-01',
    region: 'us-east-1',
    signatureVersion: 'v4',
    endpoint: uploadLocation.endpoint,
    credentials: new AWS.Credentials(
        uploadLocation.accessKey,
        uploadLocation.secretAccessKey,
        uploadLocation.sessionToken)
});

thus , We can use s3 The instance uploads the required number of files . In this example , Everything is contained in a single zip In file , So we can use a single upload call . If you have multiple files , Just use different “Body” and “Key” Property to perform multiple s3.upload call . Make sure to use Reichstag.zip Position replacement of path_to_file.

const input = 'path_to_file/Reichstag.zip';
const fs = require('fs');
await s3.upload({
    
    Body: fs.createReadStream(input),
    Bucket: uploadLocation.bucket,
    Key: `${
      uploadLocation.prefix}Reichstag.zip`
}).promise();

Step 3: Notify ion that you are finished uploading

After the data is uploaded , We will use response.onComplete The message in the object emits a second POST request . This tells the server that all source data has been uploaded , And you can start tiling The process .

const onComplete = response.onComplete;
await request({
    
    url: onComplete.url,
    method: onComplete.method,
    headers: {
     Authorization: `Bearer ${
      accessToken}` },
    json: true,
    body: onComplete.fields
});

Step 4: Monitor the tiling status

Now? asset Has been tiled into 3D Tiles And there are no steps to do . You can go to Asset Dashboard see tile speed of progress , You can also use REST API To monitor progress , So that you can take some action when you finish .
This can be used GET / v1 / assets / {assetId} Endpoint to achieve , among {assetId} It's the beginning POST In response response.assetMetadata.id.

async function waitUntilReady() {
    
    const assetId = response.assetMetadata.id;

    // Issue a GET request for the metadata
    const assetMetadata = await request({
    
        url: `https://api.cesium.com/v1/assets/${
      assetId}`,
        headers: {
     Authorization: `Bearer ${
      accessToken}` },
        json: true
    });

    const status = assetMetadata.status;
    if (status === 'COMPLETE') {
    
        console.log('Asset tiled successfully');
        console.log(`View in ion: https://cesium.com/ion/assets/${
      assetMetadata.id}`);
    } else if (status === 'DATA_ERROR') {
    
        console.log('ion detected a problem with the uploaded data.');
    } else if (status === 'ERROR') {
    
        console.log('An unknown tiling error occurred, please contact [email protected]');
    } else {
    
        if (status === 'NOT_STARTED') {
    
            console.log('Tiling pipeline initializing.');
        } else {
     // IN_PROGRESS
            console.log(`Asset is ${
      assetMetadata.percentComplete}% complete.`);
        }

        // Not done yet, check again in 10 seconds
        setTimeout(waitUntilReady, 10000);
    }
}

waitUntilReady();