Error in accessing file from Knowledge Base while creating plugin

Agree with raghuvarann, please check the security privileges for the users trying to access the file.

Ok, Please share me those details. And in addition I have shared a sample code for an alternative API which I have always used. 

1. Are you trying to access a document from Appian's internal content manager to read/write and manipulate the content/data?
   1. Note: The documents inside Appian will be directly stored into the file system of the application server not in the KDB. Only the reference/analytic data and other metadata will be stored in Appian's content KDB
2. Do you always access a Appian file or do you sometimes access Appian document folders direcly? I mean pass folderId instead of document Id to your smartservice

If you just want read/write a appian document, you can do it through this java api. I have used this api in all the smartservices which involves file manipulation, And it works fine 

Long documentId = 123L; /* Input document ID */
String filePath = cs.getInternalFilename(_cs.getVersion(documentId,ContentConstants.VERSION_CURRENT));  /* you will get something like, C:\appian\_admin\accdocs1\1\10000001.pdf */
File jAppianFile = new File(filePath);

Thanks,

Raghu

I'm attaching the code, this may help you .

package com.xyz.plugin;

import java.io.File;
import java.io.FileOutputStream;
import java.util.Scanner;

import org.apache.commons.io.FilenameUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.log4j.Logger;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.xssf.streaming.SXSSFSheet;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;

import com.appiancorp.suiteapi.common.Name;
import com.appiancorp.suiteapi.content.ContentConstants;
import com.appiancorp.suiteapi.content.ContentService;
import com.appiancorp.suiteapi.knowledge.Document;
import com.appiancorp.suiteapi.knowledge.DocumentDataType;
import com.appiancorp.suiteapi.process.exceptions.SmartServiceException;
import com.appiancorp.suiteapi.process.framework.AppianSmartService;
import com.appiancorp.suiteapi.process.framework.Input;
import com.appiancorp.suiteapi.process.framework.Required;
import com.appiancorp.suiteapi.process.framework.SmartServiceContext;
import com.appiancorp.suiteapi.process.palette.IdentityManagement;
import com.xyz.plugin.model.Type2;

@IdentityManagement
public class xyzDecisionTable extends AppianSmartService {

protected final SmartServiceContext smartServiceCtx;
protected final ContentService cs;
private static final Logger LOG = Logger.getLogger(xyzDecisionTable.class);
private Long sourceDocument;
private Long resultDocument;

public xyzDecisionTable(SmartServiceContext smartServiceCtx, ContentService cs) {

super();
LOG.info("Super call");
this.smartServiceCtx = smartServiceCtx;
this.cs = cs;
}

@Override
public void run() throws SmartServiceException {
// TODO Auto-generated method stub
try {
LOG.info("Pradeep : " + "Run started");
String[] ruleSet = new String[] { "RuleSet", "rules" };
String[] imports = new String[] { "import", "com.appian.test.Type2" };
String[] ruleTable = new String[] { "RuleTableMctRules" };
String[] condition = new String[] { "CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION",
"CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION",
"CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION",
"CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION",
"CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION",
"CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION", "CONDITION",
"CONDITION", "ACTION" };
String[] objectOftype = new String[] { "MctType2:Type2" };
String[] params = new String[] { "recordType==\"$param\"", "arrivalStation==\"$param\"", "time==\"$param\"",
"internationalOrDomesticStatus==\"$param\"", "depatureStation==\"$param\"",
"arrivalCarrier==\"$param\"", "arrivalCodeShareIndicator==\"$param\"",
"arrivalCodeShareOperatingCarrier==\"$param\"", "depatureCarrier==\"$param\"",
"depatureCodeShareIndicator==\"$param\"", "depatureCodeShareOperatingCarrier==\"$param\"",
"arrivalAircraftType==\"$param\"", "arrivalAircraftBody==\"$param\"",
"depatureAircraftType==\"$param\"", "epatureAircraftBody==\"$param\"",
"arrivalTerminal==\"$param\"", "depatureTerminal==\"$param\"", "previousCountry==\"$param\"",
"previousStation==\"$param\"", "nextCountry==\"$param\"", "nextStation==\"$param\"",
"arrivalFlightNumberRangeStart==\"$param\"", "arrivalFlightNumberRangeEnd==\"$param\"",
"depatureFlightNumberRangeStart==\"$param\"", "depatureFlightNumberRangeEnd==\"$param\"",
"previousState==\"$param\"", "nextState==\"$param\"", "previousRegion==\"$param\"",
"nextRegion==\"$param\"", "effectiveFromDate==\"$param\"", "effectiveToDate==\"$param\"",
"carrierSupression==\"$param\"", "supressionIndicator==\"$param\"", "supressionRegion==\"$param\"",
"supressionCountry==\"$param\"", "supressionState==\"$param\"",
"submittingCarrierIdentifier==\"$param\"", "filingDate==\"$param\"", "actionIndicator==\"$param\"",
"spare==\"$param\"", "recordSerialNumber==\"$param\"", "MctType2.setRunTimeValue(\"$param\");" };

Document d = xyzDecisionTable.getDocumentFromAppian(cs, sourceDocument);
String path = xyzDecisionTable.getInternalFilePath(cs, d);
// FileOutputStream fileOut = new FileOutputStream(FILE_NAME);
File file = new File(path);
LOG.info("uploaded file path : " + path);
SXSSFWorkbook workbook = new SXSSFWorkbook(100);
Sheet sh = workbook.createSheet();

Row ruleSetRow = sh.createRow(0);
for (int i = 0; i < ruleSet.length; i++) {
Cell cell = ruleSetRow.createCell(i);
cell.setCellValue(ruleSet[i]);
}
Row importsRow = sh.createRow(1);
for (int i = 0; i < imports.length; i++) {
Cell cell = importsRow.createCell(i);
cell.setCellValue(imports[i]);
}

Row ruleTableRow = sh.createRow(2);
for (int i = 0; i < ruleTable.length; i++) {
Cell cell = ruleTableRow.createCell(i);
cell.setCellValue(ruleTable[i]);
}

Row conditionRow = sh.createRow(3);
for (int i = 0; i < condition.length; i++) {
Cell cell = conditionRow.createCell(i);
cell.setCellValue(condition[i]);
}

Row objectOftypeRow = sh.createRow(4);
for (int i = 0; i < objectOftype.length; i++) {
Cell cell = objectOftypeRow.createCell(i);
cell.setCellValue(objectOftype[i]);
}
sh.addMergedRegion(new CellRangeAddress(4, 4, 0, 40));
Row paramsRow = sh.createRow(5);
for (int i = 0; i < params.length; i++) {
Cell cell = paramsRow.createCell(i);
cell.setCellValue(params[i]);
}

int rowNum = 6;

Scanner sc1 = new Scanner(file);

while (sc1.hasNextLine()) {
String line = sc1.nextLine();
Type2 type2 = new Type2();
type2.setRecordType("" + line.charAt(0));
type2.setArrivalStation(line.substring(1, 4));
type2.setTime(line.substring(4, 8));
type2.setInternationalOrDomesticStatus(line.substring(8, 10));
type2.setDepatureStation(line.substring(10, 13));
type2.setArrivalCarrier(line.substring(13, 15));
type2.setArrivalCodeShareIndicator(line.substring(15, 16));
type2.setArrivalCodeShareOperatingCarrier(line.substring(16, 18));
type2.setDepatureCarrier(line.substring(18, 20));
type2.setDepatureCodeShareIndicator(line.substring(20, 21));
type2.setDepatureCodeShareOperatingCarrier(line.substring(21, 23));
type2.setArrivalAircraftType(line.substring(23, 26));
type2.setArrivalAircraftBody(line.substring(26, 27));
type2.setDepatureAircraftType(line.substring(27, 30));
type2.setDepatureAircraftBody(line.substring(30, 31));
type2.setArrivalTerminal(line.substring(31, 33));
type2.setDepatureTerminal(line.substring(33, 35));
type2.setPreviousCountry(line.substring(35, 37));
type2.setPreviousStation(line.substring(37, 40));
type2.setNextCountry(line.substring(40, 42));
type2.setNextStation(line.substring(42, 45));
type2.setArrivalFlightNumberRangeStart(line.substring(45, 49));
type2.setArrivalFlightNumberRangeEnd(line.substring(49, 53));
type2.setDepatureFlightNumberRangeStart(line.substring(53, 57));
type2.setDepatureFlightNumberRangeEnd(line.substring(57, 61));
type2.setPreviousState(line.substring(61, 63));
type2.setNextState(line.substring(63, 65));
type2.setPreviousRegion(line.substring(65, 68));
type2.setNextRegion(line.substring(68, 71));
type2.setEffectiveFromDate(line.substring(71, 78));
type2.setEffectiveToDate(line.substring(78, 85));
type2.setCarrierSupression(line.substring(85, 86));
type2.setSupressionIndicator(line.substring(86, 87));
type2.setSupressionRegion(line.substring(87, 90));
type2.setSupressionCountry(line.substring(90, 92));
type2.setSupressionState(line.substring(92, 94));
type2.setSubmittingCarrierIdentifier(line.substring(94, 96));
type2.setFilingDate(line.substring(96, 103));
type2.setActionIndicator(line.substring(103, 104));
type2.setSpare(line.substring(104, 194));
type2.setRecordSerialNumber(line.substring(194, 200));
type2.setRunTimeValue("" + rowNum);

Row row = sh.createRow(rowNum++);
row.createCell(0).setCellValue(type2.getRecordType());
row.createCell(1).setCellValue(type2.getArrivalStation());
row.createCell(2).setCellValue(type2.getTime());
row.createCell(3).setCellValue(type2.getInternationalOrDomesticStatus());
row.createCell(4).setCellValue(type2.getDepatureStation());
row.createCell(5).setCellValue(type2.getArrivalCarrier());
row.createCell(6).setCellValue(type2.getArrivalCodeShareIndicator());
row.createCell(7).setCellValue(type2.getArrivalCodeShareOperatingCarrier());
row.createCell(8).setCellValue(type2.getDepatureCarrier());
row.createCell(9).setCellValue(type2.getDepatureCodeShareIndicator());
row.createCell(10).setCellValue(type2.getDepatureCodeShareOperatingCarrier());
row.createCell(11).setCellValue(type2.getArrivalAircraftType());
row.createCell(12).setCellValue(type2.getArrivalAircraftBody());
row.createCell(13).setCellValue(type2.getDepatureAircraftType());
row.createCell(14).setCellValue(type2.getDepatureAircraftBody());
row.createCell(15).setCellValue(type2.getArrivalTerminal());
row.createCell(16).setCellValue(type2.getDepatureTerminal());
row.createCell(17).setCellValue(type2.getPreviousCountry());
row.createCell(18).setCellValue(type2.getPreviousStation());
row.createCell(19).setCellValue(type2.getNextCountry());
row.createCell(20).setCellValue(type2.getNextStation());
row.createCell(21).setCellValue(type2.getArrivalFlightNumberRangeStart());
row.createCell(22).setCellValue(type2.getArrivalFlightNumberRangeEnd());
row.createCell(23).setCellValue(type2.getDepatureFlightNumberRangeStart());
row.createCell(24).setCellValue(type2.getDepatureFlightNumberRangeEnd());
row.createCell(25).setCellValue(type2.getPreviousState());
row.createCell(26).setCellValue(type2.getNextState());
row.createCell(27).setCellValue(type2.getPreviousRegion());
row.createCell(28).setCellValue(type2.getNextRegion());
row.createCell(29).setCellValue(type2.getEffectiveFromDate());
row.createCell(30).setCellValue(type2.getEffectiveToDate());
row.createCell(31).setCellValue(type2.getCarrierSupression());
row.createCell(32).setCellValue(type2.getSupressionIndicator());
row.createCell(33).setCellValue(type2.getSupressionRegion());
row.createCell(34).setCellValue(type2.getSupressionCountry());
row.createCell(35).setCellValue(type2.getSupressionState());
row.createCell(36).setCellValue(type2.getSubmittingCarrierIdentifier());
row.createCell(37).setCellValue(type2.getFilingDate());
row.createCell(38).setCellValue(type2.getActionIndicator());
row.createCell(39).setCellValue(type2.getSpare());
row.createCell(40).setCellValue(type2.getRecordSerialNumber());
row.createCell(41).setCellValue(type2.getRunTimeValue());
type2 = null;
if (rowNum % 100 == 0) {
((SXSSFSheet) sh).flushRows(100);
}
}

sc1.close();

LOG.info("Rules File createed");

// creates a document
// AppianUtils.createDocumentInAppian(cs, path, null, sourceDocument,
// d.getName(), d.getDescription());

String fileName = FilenameUtils.getBaseName(path);
LOG.info("Pradeep " + fileName);
Document newDoc = null;
Long newDocumentId = null;

newDoc = new Document(d.getCurrentContentId(), "rules", "xlsx");

newDoc.setState(ContentConstants.STATE_PUBLISHED);
newDocumentId = cs.create(d, ContentConstants.UNIQUE_NONE);
newDoc.setId(newDocumentId);
LOG.info("Pradeep " + newDocumentId);
String dpath = xyzDecisionTable.getInternalFilePath(cs, newDoc);
LOG.info("Pradeep " + dpath);

File f = new File(dpath);
FileOutputStream out = new FileOutputStream(f);
workbook.write(out);
// fileOut.close();
out.close();
workbook.close();

resultDocument = newDocumentId;

} catch (Exception e) {
LOG.info("Pradeep Error Occured");
LOG.info(e);
}

}

public static Document getDocumentFromAppian(ContentService cs, Long documentId) throws Exception {
Document[] docs = (Document[]) cs.download(documentId, ContentConstants.VERSION_CURRENT,
Boolean.valueOf(false));
if (docs.length > 0) {
LOG.info("Document size in k : " + docs[0].getSizeInKB());
LOG.info("Document : " + docs[0]);
LOG.info("Document Id : " + documentId);

return docs[0];
} else {
return null;
}
}

public static String getInternalFilePath(ContentService cs, Document d) throws Exception {
String path = cs.getInternalFilename(d.getId());

if (StringUtils.isBlank(path)) {
path = d.getInternalFilename();
}

return path;
}

@Input(required = Required.ALWAYS)
@Name("sourceDocument")
@DocumentDataType
public void setSourceDocument(Long val) {
this.sourceDocument = val;
}

@Name("resultDocument")
@DocumentDataType
public Long getResultDocument() {
return resultDocument;
}

}

** UPDATED THE EMBEDDED CODE IN PREVIOUS REPLY **

1. You may not need cs.download() for your requirement, you can directly use cs.getInternalFileName(), refer the updated code in my previous reply.
2. Since you are writing INFO level logs, Check if you have enabled INFO level logs for your class in the Appian's log4j properties. This might be the reason why you dint see any log entries in the application server logs. Either,
   • Temporarily change all logs to ERROR level like LOG.error("TEST LOG"); which we can change to appropriate levels once development and debugging is done --OR--
   • Enable INFO level logs in log4j.properties

Thanks,

Raghu