The productions are components developed with InterSystems IRIS Interoperability module to promote integrations between systems, data sources/targets, web services, API, message channels, etc. Productions are composed by:
1) Business services to get/ingest/get data events or requests;
2) Business operations to send or persist data to repositories, systems, API, web services, etc; and
3) BPL - BPEL flows to orchestrate, mediate, compose and route data from business services to business operations.
In this article I will show you how to create a custom business service to get a file from a multipart HTTP request and enable it into a production using class comments, see:
Class dc.upload.UploadService Extends Ens.BusinessService
{ // extends Ens.BusinessService to create a custom Business service using Object Script
// This class receive a file from a multipart http request and save to the folder configured
// into folder parameter
//Choose an adapter to get data from a source of data
//HTTP.InboundAdapter allows you get data from an http request
Parameter ADAPTER = "EnsLib.HTTP.InboundAdapter";
//custom parameter to allows production user set destination folder to multipart file uploaded
Property Folder As %String(MAXLEN = 100);
//when you set parameter Folder to SETTINGS parameter, the production IRIS interface create a field
//to the user fills
//so the user will inform host path for the uploaded file
Parameter SETTINGS = "Folder,Basic";
//This method is mandatory to have a business service. It receives the multipart file into pInput
//and returns a result to the caller using pOutput
Method OnProcessInput(pInput As %GlobalBinaryStream, pOutput As %RegisteredObject) As %Status
{
//try to do the actions
try {
Set reader = ##class(%Net.MIMEReader).%New() //creates a MIMEReader to extract files from
//multipart requests
Do reader.OpenStream(pInput) //reader open the file
Set tSC = reader.ReadMIMEMessage(.message) //the reader put the file uploaded into a MIME Message
//Get Header obtains headers from the request and the multipart file, like content-type
//or content disposition
//the content disposition have 3 headers:
// Content-Disposition: form-data; name="file"; filename="filename.ext"
//This split content-disposition header into 3 parts
Set filenameHeader = $PIECE(message.GetHeader("CONTENT-DISPOSITION", .header),";",3)
//get filename header value
Set filename = $EXTRACT(filenameHeader, 12, $LENGTH(filenameHeader)-1)
//Headers are not more needed. It clean the header to remains only the file content to be saved
Do message.ClearHeaders()
//create a file object to save the multipart file
Set file=##class(%Stream.FileBinary).%New()
//points the file to folder informed into folder parameter, plus upload filename from header
Set file.Filename=..Folder_filename
//save body message (the file content) to file object
Do file.CopyFromAndSave(message.Body)
//return a sucess message to the user/caller
Set pOutput = "File "_filename_" uploaded with success to: "_..Folder_filename
Set tSC=$$$OK
//returns error message to the user
} catch e {
Set tSC=e.AsStatus()
Set pOutput = tSC
}
Quit tSC
}
}
I created an application into the Open Exchange to show you this business class. To test this code, use it. Follow the steps:
1) Go to: https://openexchange.intersystems.com/package/upload-adapter
2) Into your terminal/cmd execute: git clone https://github.com/yurimarx/upload-adapter.git
3) Into your terminal/cmd execute: docker-compose build and after execute docker-compose up -d
4) Open the production
5) Set the host destination folder to the uploaded files and start the production. See:
6) Now Open Postman or create a multipart request into a form pointing to localhost:9980/ using POST with a form-data file attribute. See sample:
7) Check the upload into your IRIS docker instance.
Now, with this business service, you have alternatives to send a file to your docker instance using postman or a html form and compose this feature with BPL and business operations. Fantastic!
PS: a loved ObjectScript MIMEReader and MIME* classes.