private String extractTextFromImage(File tempFile) throws TesseractException {

  ITesseract tesseract = new Tesseract();
  tesseract.setDatapath("/usr/share/tessdata/"); //directory to trained models
  tesseract.setLanguage("eng+por"); // choose your language/trained model

  return tesseract.doOCR(tempFile); //call tesseract function doOCR() //passing the file to be processed with OCR technique

}

ARG IMAGE=store/intersystems/iris-community:2020.1.0.204.0
ARG IMAGE=intersystemsdc/iris-community:2020.1.0.209.0-zpm
ARG IMAGE=intersystemsdc/iris-community:2020.2.0.204.0-zpm
ARG IMAGE=intersystemsdc/irishealth-community:2020.3.0.200.0-zpm
ARG IMAGE=intersystemsdc/iris-community:2020.3.0.200.0-zpm
ARG IMAGE=intersystemsdc/iris-community:2020.3.0.221.0-zpm
ARG IMAGE=intersystemsdc/iris-community:2020.4.0.521.0-zpm
FROM $IMAGE

USER root   

WORKDIR /opt/irisapp
RUN chown ${ISC_PACKAGE_MGRUSER}:${ISC_PACKAGE_IRISGROUP} /opt/irisapp
USER ${ISC_PACKAGE_MGRUSER}

COPY  Installer.cls .
COPY  src src

COPY iris.script /tmp/iris.script

RUN iris start IRIS \
    && iris session IRIS < /tmp/iris.script \
    && iris stop IRIS quietly

USER root   

# Install Java 8 using apt-get from ubuntu repository
RUN apt-get update && \
    apt-get install -y openjdk-8-jdk && \
    apt-get install -y ant && \
    apt-get clean && \
    rm -rf /var/lib/apt/lists/* && \
    rm -rf /var/cache/oracle-jdk8-installer;

# Fix certificate issues, found as of 
# https://bugs.launchpad.net/ubuntu/+source/ca-certificates-java/+bug/983302
RUN apt-get install -y ca-certificates-java && \
    apt-get clean && \
    update-ca-certificates -f && \
    rm -rf /var/lib/apt/lists/* && \
    rm -rf /var/cache/oracle-jdk8-installer;

# Setup JAVA_HOME, to enable apps to know where the Java was installed
ENV JAVA_HOME /usr/lib/jvm/java-8-openjdk-amd64/
RUN export JAVA_HOME
ENV JRE_HOME /usr/lib/jvm/java-8-openjdk-amd64/
RUN export JRE_HOME

# Setup classpath, to enable apps to know where java classes and java jar libraries was installed
ENV classpath .:/usr/irissys/dev/java/lib/JDK18/*:/opt/irisapp/*:/usr/irissys/dev/java/lib/gson/*
:/usr/irissys/dev/java/lib/jackson/*:/jgw/*
RUN export classpath
ENV CLASSPATH .:/usr/irissys/dev/java/lib/JDK18/*:/opt/irisapp/*:/usr/irissys/dev/java/lib/gson/*
:/usr/irissys/dev/java/lib/jackson/*:/jgw/*
RUN export CLASSPATH

USER root

ARG APP_HOME=/tmp/app

COPY src $APP_HOME/src

# Tess4J and another java libraries used, are into jgw folder and jgw folder is in the classpath
COPY jgw /jgw

# Copy our Java OCR program, packaged into a jar, to the jgw
COPY target/ocr-pex-1.0.0.jar /jgw/ocr-pex-1.0.0.jar  

COPY jgw/* /usr/irissys/dev/java/lib/JDK18/

# Install tesseract using ubuntu apt-get
RUN apt-get update && apt-get install tesseract-ocr -y

USER root

# Copy trained models eng and por to the models folder
COPY tessdata /usr/share/tessdata

# Install and config default OS locale - it is required to tesseract works fine
RUN apt-get update && apt-get install -y locales && rm -rf /var/lib/apt/lists/* \
 && locale-gen "en_US.UTF-8"
ENV LANG=en_US.UTF-8 \
    LANGUAGE=en_US:en \
    LC_ALL=en_US.UTF-8

Class dc.ocr.OcrProduction Extends Ens.Production
{

XData ProductionDefinition
{

<Production Name="dc.ocr.OcrProduction" LogGeneralTraceEvents="false">
  <Description></Description>
  <ActorPoolSize>2</ActorPoolSize>
  <Item Name="OcrService" Category="" ClassName="dc.ocr.OcrService" PoolSize="1" Enabled="true" 
Foreground="false" Comment="" LogTraceEvents="false" Schedule="">
  </Item>

  <Item Name="JavaGateway" Category="" ClassName="EnsLib.JavaGateway.Service" PoolSize="1" 
Enabled="true" Foreground="false" Comment="" LogTraceEvents="false" Schedule="">
    <Setting Target="Host" Name="ClassPath">.:/usr/irissys/dev/java/lib/JDK18/*:/opt/irisapp/*
:/usr/irissys/dev/java/lib/gson/*
:/usr/irissys/dev/java/lib/jackson/*:/jgw/ocr-pex-1.0.0.jar
</Setting>
    <Setting Target="Host" Name="JavaHome">/usr/lib/jvm/java-8-openjdk-amd64/</Setting>
  </Item>

</Production>

}

Class dc.ocr.OcrService 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)

        // Connect a Gateway instance to server JavaGate on the host machine
        set GW = ##class(%Net.Remote.Gateway).%New()
        set st = GW.%Connect("127.0.0.1", "55555", "IRISAPP",,)
        //instantiate java ocr class
        set proxyOcr = ##class(%Net.Remote.Object).%New(GW,"community.intersystems.pex.ocr.OcrOperation")
        //call ocr method to get text from image
        set pResponse = proxyOcr.doOcr(file.Filename)
        //returns to the service
        Set pOutput = pResponse
        Set tSC=$$$OK

    //returns error message to the user
    } catch e {
        Set tSC=e.AsStatus()
        Set pOutput = tSC
    }

    Quit tSC
}

}