Modifying HTTP Call for Scheduler to Upload Dashboard Images

Question

I have created the HTTP method using this post. But I'm unsure of how to test it out. Say if I run this in the Developer Console for testing how Can I link it to taking the image out of the Salesforce Dashboard and uploading it into the Document Folder so that the Image can be send upload else where?

I already have the URL to those Dashboard images that I want to upload

How do I link this to getting a image from Salesforce Dashboard and uploading it into the Document Folder?

---

Codes

public class testFBInt {

public void exInt() {

  HttpRequest req = new HttpRequest();
    req.setEndpoint('https://test.salesforce.com/services/oauth2/token');
    req.setMethod('POST');
    req.setBody(buildHttpQuery(new Map<String, String> {
        'grant_type' => 'password',
        'username' => 'username',
        'password' => 'password',
        'client_id' => 'Consumer_id',
        'client_secret' => 'Consumer_key'
         }));

 }

  static String buildHttpQuery(Map<String, String> queryParams) {
    if (queryParams.isEmpty()) {
        return '';
    }

    String[] params = new String[] {};
    for (String k : queryParams.keySet()) {
        String v = EncodingUtil.urlEncode(queryParams.get(k), 'UTF-8');

        params.add(String.format('{0}={1}', new String[] { k, v }));
    }

    return String.join(params, '&');
 }

}

Answer 1

Based on your statement

I already have the URL to those Dashboard images that I want to upload

From here, there are 3 task you talked about. All these can be done in a scheduler job.

One: Fetching the image body as base64data.

Get the access token first. Reference: Alan's answer here

Lets say your URL is in variable - dashboardImageURL.

String base64Data;
httprequest req = new httprequest();
req.setEndpoint(dashboardImageURL);
req.setmethod('GET');
req.setHeader('Authorization', 'OAuth ' + access_token);
http http = new http();
httpresponse res = http.send(req);
Blob image = res.getBodyAsBlob();
base64Data =  EncodingUtil.base64Encode(image);

Two: Saving the image as Document in current org.

Document docatt = new Document();
docatt.Name = 'Chart 1.jpg';
docatt.Body = EncodingUtil.base64Decode(base64Data);
docatt.FOLDERID = '00l6F231005tqGi'; //Your folder id
docatt.IsPublic = true;

insert docatt;

You can have a scheduler job to run at any specific time with these 2 snippets to save the image from the URL.

Three: Sending the image to Facebook.

For this you will need to make another callout to facebook with the image body set in the httprequest body. This is not a part of the question, so I am just over-lining it. You can write it in a separate scheduler if you want to send it at a different time or in the same scheduler job.