com.afrigis.services.impl.AbstractResponse Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of core Show documentation
Show all versions of core Show documentation
Core Java library to ease use of AfriGIS Services
package com.afrigis.services.impl;
import java.io.ByteArrayOutputStream;
import java.io.InputStream;
import java.nio.charset.Charset;
import org.apache.commons.codec.binary.StringUtils;
import org.apache.commons.io.IOUtils;
import org.apache.http.HttpStatus;
import org.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.afrigis.services.Response;
import com.afrigis.services.exceptions.AfriGISServicesException;
import com.afrigis.services.internal.saas.api2.impl.ParsedErrorData;
import com.google.gson.Gson;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
/**
*
* Abstract implementation for {@link Response}.
*
*
* @author hendrikc
*
*/
public abstract class AbstractResponse implements Response {
private static final int OK_200 = 200;
private static final Charset UTF8 = Charset.forName("UTF-8");
private byte[] rawData;
private int httpStatusCode;
private String errMsg;
private ParsedErrorData error;
private int timesCalled;
@Override
public byte[] getByteArray() {
return rawData != null ? rawData.clone() : null;
}
/**
*
* @return the raw data array direct (NOT a copy)
*/
protected byte[] getByteArrayInternal() {
return rawData;
}
/**
*
* Essentially returns TRUE if we received any suspect http status code.
*
*
* Note that the SaaS server, at time of writing, does not seem to honour
* HTTP status codes for response. For example, it will happily return 200
* while authentication failed. SO just be aware this method might require
* some more intelligence or something.
*
*
* @return true if this is an error response
*/
public boolean isError() {
boolean ret = false;
switch (httpStatusCode) {
case HttpStatus.SC_ACCEPTED:
case HttpStatus.SC_OK:
case HttpStatus.SC_CREATED:
case 0:
ret = false;
break;
default:
ret = true;
break;
}
// Actual HTTP status code is not accurate reflection of response error
// status
return ret | error != null;
}
@Override
public void consume(InputStream fin, int realHttpStatusCode) {
this.httpStatusCode = realHttpStatusCode;
final ByteArrayOutputStream fout = new ByteArrayOutputStream();
try {
IOUtils.copy(fin, fout);
IOUtils.closeQuietly(fout);
final String rawString = fout.toString(UTF8.name());
rawData = fout.toByteArray();
error = checkForErrorCondition(rawString);
log().trace("Received from server:\n" + rawString);
log().trace("Result: {}", realHttpStatusCode);
} catch (Exception e) {
realHttpStatusCode = HttpStatus.SC_INTERNAL_SERVER_ERROR;
errMsg = e.getMessage();
log().error(
"Unexpected exception caught while consuming server response",
e);
}
}
/**
*
* Complets the parsing of the received response.
*
*
* @param input
* the input as received from server.
*/
protected abstract void completeBuild(byte[] input);
@Override
public void completeBuild() {
completeBuild(rawData);
}
/**
*
* Attempts to deserialize the received server response.
*
*
* @param
* a class that implements {@link Response}
* @param input
* a json string received from server side services
* @param type
* the type of the {@link Response} implementation
* @return the deserialized object
*/
public static T build(String input, Class type) {
final ParsedErrorData error = checkForErrorCondition(input);
if (error != null) {
throw new AfriGISServicesException(error);
} else {
final Gson gson = new Gson();
final JsonParser parser = new JsonParser();
try {
final JsonObject jsonObject = (JsonObject) parser.parse(input);
return gson.fromJson(jsonObject, type);
} catch (Exception e) {
LoggerFactory.getLogger(type)
.error("Error encountered in build", e);
return null;
}
}
}
private static ParsedErrorData checkForErrorCondition(String rawString) {
JSONObject parsed = null;
try {
parsed = new JSONObject(rawString);
} catch (Exception e) {
LoggerFactory.getLogger(AbstractResponse.class).warn(
"Failed to parse response as JSON - this is not expected. The received content is\n{}\n",
rawString, e);
}
try {
if (parsed != null) {
int httpStatusCode = 0;
String errMsg = "";
ParsedErrorData error;
if (parsed.has("statusCode") && parsed.getInt("statusCode") != 200) {
httpStatusCode = parsed.getInt("statusCode");
errMsg = parsed.optString("message","No Message Available");
}
if (httpStatusCode != OK_200 && httpStatusCode != 0) {
error = new ParsedErrorData();
error.setMessage(errMsg);
error.setSource(parsed.has("source")
? parsed.getString("source") : "Unknown");
error.setStatusCode(httpStatusCode);
return error;
}
}
} catch (Exception e) {
LoggerFactory.getLogger(AbstractResponse.class).warn(
"Treating the response as JSON failed, assuming there is much wrong",
e);
return new ParsedErrorData();
}
return null;
}
/**
*
* Retrieves error message if available.
*
*
* @return the error message if available, otherwise empty string (
* "")
*/
public String getErrorMessage() {
return errMsg;
}
/**
*
* Extracts the the HTTP status code if possible.
*
*
* @return the HTTP status code if possible, otherwise returns 0 (zero)
*/
public int getHttpStatusCode() {
return this.httpStatusCode;
}
@Override
public ParsedErrorData getError() {
return error;
}
@Override
public void setError(ParsedErrorData receivedErr) {
this.error = receivedErr;
}
@Override
public void setTimesCalled(int timesCalledIn) {
this.timesCalled = timesCalledIn;
}
@Override
public int getTimesCalled() {
return timesCalled;
}
/**
*
* Give you the response as received from the server, unmodified.
*
*
* Note, however, we construct the string using the raw byte array received
* from the server, with UTF-8 encoding. This MIGHT screw up if the server
* is not actually talking UTF-8
*
*
* @return the response received from the server as a string, UTF-8 encoded.
* @see String#String(byte[], Charset)
* @see StringUtils#newStringUtf8(byte[])
*/
@Override
public String toString() {
return StringUtils
.newStringUtf8(rawData != null ? rawData : new byte[0]);
}
/**
*
* @return {@link Logger} instance
*/
protected Logger log() {
return LoggerFactory.getLogger(getClass());
}
}