Here is solution to upload file in third party system using apex in salesforce.
below is formdata builder apex class which is building required parameters.
// The boundary is alligned so it doesn't produce padding characters when base64 encoded.
private final static string Boundary = '1ff13444ed8140c7a32fc4e6451aa76d';
/**
* Returns the request's content type for multipart/form-data requests.
*/
public static string GetContentType() {
return 'multipart/form-data; charset="UTF-8"; boundary="' + Boundary + '"';
}
/**
* Pad the value with spaces until the base64 encoding is no longer padded.
*/
private static string SafelyPad(string value,string valueCrLf64,string lineBreaks) {
string valueCrLf = '';
blob valueCrLfBlob = null;
while (valueCrLf64.endsWith('=')) {
value += ' ';
valueCrLf = value + lineBreaks;
valueCrLfBlob = blob.valueOf(valueCrLf);
valueCrLf64 = EncodingUtil.base64Encode(valueCrLfBlob);
}
return valueCrLf64;
}
/**
* Write a boundary between parameters to the form's body.
*/
public static string WriteBoundary() {
string value = '--' + Boundary + '\r\n';
blob valueBlob = blob.valueOf(value);
return EncodingUtil.base64Encode(valueBlob);
}
/**
* Write a boundary at the end of the form's body.
*/
public static string WriteBoundary(
EndingType ending) {
string value = '';
if (ending == EndingType.Cr) {
// The file's base64 was padded with a single '=',
// so it was replaced with '\r'. Now we have to
// prepend the boundary with '\n' to complete
// the line break.
value += '\n';
} else if (ending == EndingType.None) {
// The file's base64 was not padded at all,
// so we have to prepend the boundary with
// '\r\n' to create the line break.
value += '\r\n';
}
// Else:
// The file's base64 was padded with a double '=',
// so they were replaced with '\r\n'. We don't have to
// do anything to the boundary because there's a complete
// line break before it.
value += '--' + Boundary + '--';
blob valueBlob = blob.valueOf(value);
return EncodingUtil.base64Encode(valueBlob);
}
/**
* Write a key-value pair to the form's body.
*/
public static string WriteBodyParameter(string key, string value) {
string contentDisposition = 'Content-Disposition: form-data; name="' + key + '"';
string contentDispositionCrLf = contentDisposition + '\r\n\r\n';
blob contentDispositionCrLfBlob = blob.valueOf(contentDispositionCrLf);
string contentDispositionCrLf64 = EncodingUtil.base64Encode(contentDispositionCrLfBlob);
string content = SafelyPad(contentDisposition, contentDispositionCrLf64, '\r\n\r\n');
if(key=='file'){
system.debug(value);
}
string valueCrLf = value + '\r\n';
blob valueCrLfBlob = blob.valueOf(valueCrLf);
if(key=='file'){
system.debug(valueCrLfBlob );
}
string valueCrLf64 = EncodingUtil.base64Encode(valueCrLfBlob);
integer file64Length = valueCrLf64 .length();
String last4Bytes = valueCrLf64 .substring(valueCrLf64 .length()-4,valueCrLf64 .length());
content += SafelyPad(value, valueCrLf64, '\r\n');
return content;
}
/**
* Helper enum indicating how a file's base64 padding was replaced.
*/
public enum EndingType {
Cr,
CrLf,
None
}
public static string writeFileBody(String key ,Blob attachBody,string filename)
{
String header = '--' + boundary + '\r\n' +
+ 'Content-Type: application/octet-stream\r\n'+
+ 'Content-Disposition: form-data; name="'+key+'";filename="' + filename +'"';
String headerEncoded = EncodingUtil.base64Encode(Blob.valueOf(header + '\r\n\r\n'));
while(headerEncoded.endsWith('=')){
header += ' ';
headerEncoded = EncodingUtil.base64Encode(Blob.valueOf(header+'\r\n\r\n'));
}
String footer = '--' + boundary + '--';
String bodyEncoded = EncodingUtil.base64Encode(attachBody);
return headerEncoded+bodyEncoded;
}
/**
*this method will work for only parameters in the form data
*/
public static string append(string key , string value ){
string formParam=FormData.WriteBoundary()+WriteBodyParameter(key, value);
return formParam;
}
/**
*this method will work for file parameters and other params in the form data
*/
public static Blob makeBlobWithFile(String key ,Blob attachBody,string filename,string otherParamsEncoded){
String header = '--' + boundary + '\r\n' +
+ 'Content-Type: application/octet-stream\r\n'+
+ 'Content-Disposition: form-data; name="'+key+'";filename="' + filename +'"';
String headerEncoded = EncodingUtil.base64Encode(Blob.valueOf(header + '\r\n\r\n'));
while(headerEncoded.endsWith('=')){
header += ' ';
headerEncoded = EncodingUtil.base64Encode(Blob.valueOf(header+'\r\n\r\n'));
}
String footer = '--' + boundary + '--';
String bodyEncoded = EncodingUtil.base64Encode(attachBody);
Blob formBlob = null;
String last4Bytes = bodyEncoded .substring(bodyEncoded.length()-4,bodyEncoded.length());
if(last4Bytes.endsWith('==')) {
last4Bytes = last4Bytes.substring(0,2) + '0K';
bodyEncoded = bodyEncoded.substring(0,bodyEncoded.length()-4) + last4Bytes;
String footerEncoded = EncodingUtil.base64Encode(Blob.valueOf(footer));
formBlob = EncodingUtil.base64Decode(otherParamsEncoded+headerEncoded+bodyEncoded+footerEncoded);
} else if(last4Bytes.endsWith('=')) {
last4Bytes = last4Bytes.substring(0,3) + 'N';
bodyEncoded = bodyEncoded.substring(0,bodyEncoded.length()-4) + last4Bytes;
footer = '\n' + footer;
String footerEncoded = EncodingUtil.base64Encode(Blob.valueOf(footer));
formBlob = EncodingUtil.base64Decode(otherParamsEncoded+headerEncoded+bodyEncoded+footerEncoded);
} else {
footer = '\r\n' + footer;
String footerEncoded = EncodingUtil.base64Encode(Blob.valueOf(footer));
formBlob = EncodingUtil.base64Decode(otherParamsEncoded+headerEncoded+bodyEncoded+footerEncoded);
}
return formBlob; // returning the form data as a blob
}
/**
*this method will make the blob of the form data if attachments are not required
*/
public static Blob makeBlob(string ParamsEncoded){
String footer = '--' + boundary + '--';
Blob formBlob = null;
//footer = '\r\n' + footer;
String footerEncoded = EncodingUtil.base64Encode(Blob.valueOf(footer));
formBlob = EncodingUtil.base64Decode(ParamsEncoded+footerEncoded);
return formBlob; // returning the form data as a blob
}
here is file upload apex class method. Where we are sending multiple parameters (metadata of document) and file body.
public void uploadFile(){
string contentType = HttpFormBuilder.GetContentType();
string form64 = '';
//adding documents metadata or properties
form64 += FormData.append('key','Value');
form64 += FormData.append('key','value');
//adding documents body with file parameter
blob formBlob= FormData.makeBlobWithFile('file',attachBody,filename,form64);
string contentLength = string.valueOf(formBlob.size());
HttpRequest httpRequest = new HttpRequest();
httpRequest.setBodyAsBlob(formBlob);
httpRequest.setHeader('Connection', 'keep-alive');
httpRequest.setHeader('Content-Length', contentLength);
httpRequest.setHeader('Content-Type', contentType);
httpRequest.setMethod('POST');
httpRequest.setTimeout(120000);
httpRequest.setHeader('Accept', 'application/json');
httpRequest.setHeader('Authorization',' ');
httpRequest.setEndpoint('END POINT');
Http http = new Http();
HttpResponse res = http.send(httpRequest);
}
Extract From:- muenzpraeger / salesforce-einstein-vision-apex