com.wso2.code.quality.matrices.RestApiCaller.java Source code

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Here is the source code for com.wso2.code.quality.matrices.RestApiCaller.java

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/*
 * Copyright (c) 2017, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
 *
 * WSO2 Inc. licenses this file to you under the Apache License,
 * Version 2.0 (the "License"); you may not use this file except
 * in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package com.wso2.code.quality.matrices;

import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.log4j.Logger;
import org.json.JSONArray;
import org.json.JSONObject;
import org.json.JSONTokener;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

/**
 * This class is used to call the REST API of both WSO2 PMT and github.com
 */

public class RestApiCaller {

    private static Logger logger = Logger.getLogger(RestApiCaller.class);

    /**
     * calling the relevant API and saving the output to a file
     *
     * @param URL                 url of the REST API to be called
     * @param accessToken         either the WSO2 PMT access accessToken or giihub.com access accessToken
     * @param requireCommitHeader should be true for accessing the github commit search API and false otherwise
     * @param requireReviewHeader should be true for accessing the github review API or false otherwise
     */

    public Object callApi(String URL, String accessToken, boolean requireCommitHeader, boolean requireReviewHeader)
            throws CodeQualityMatricesException {

        BufferedReader bufferedReader = null;
        CloseableHttpClient httpclient = null;
        CloseableHttpResponse httpResponse = null;
        Object returnedObject = null;

        try {
            httpclient = HttpClients.createDefault();
            HttpGet httpGet = new HttpGet(URL);

            if (accessToken != null) {

                httpGet.addHeader("Authorization", "Bearer " + accessToken); // passing the accessToken for the API call
            }

            //as the accept header is needed for the review API since it is still in preview mode   
            if (requireReviewHeader) {
                httpGet.addHeader("Accept", "application/vnd.github.black-cat-preview+json");
            }

            //as the accept header is needed for accessing commit search API which is still in preview mode
            if (requireCommitHeader) {
                httpGet.addHeader("Accept", "application/vnd.github.cloak-preview");
            }

            httpResponse = httpclient.execute(httpGet);
            int responseCode = httpResponse.getStatusLine().getStatusCode(); // to get the response code

            switch (responseCode) {
            case 200:
                //success
                bufferedReader = new BufferedReader(
                        new InputStreamReader(httpResponse.getEntity().getContent(), "UTF-8"));
                StringBuilder stringBuilder = new StringBuilder();
                String line;
                while ((line = bufferedReader.readLine()) != null) {
                    stringBuilder.append(line);
                }

                // creating a JSON object from the response
                String JSONText = stringBuilder.toString();
                Object json = new JSONTokener(JSONText).nextValue(); // gives an object http://stackoverflow.com/questions/14685777/how-to-check-if-response-from-server-is-jsonaobject-or-jsonarray

                if (json instanceof JSONObject) {
                    JSONObject jsonObject = (JSONObject) json;
                    returnedObject = jsonObject;
                } else if (json instanceof JSONArray) {
                    JSONArray jsonArray = (JSONArray) json;
                    returnedObject = jsonArray;
                }
                logger.info("JSON response is passed after calling the given REST API");
                break;
            case 401:
                // to handle Response code 401: Unauthorized
                throw new CodeQualityMatricesException("Response code 401 : Git hub access token is invalid");
            case 403:
                // to handle invalid credentials
                throw new CodeQualityMatricesException(
                        "Response Code:403 Invalid Credentials, insert a correct token for PMT");
            case 404:
                // to handle invalid patch
                throw new CodeQualityMatricesException("Response Code 404: Patch not found, enter a valid patch");
            default:
                returnedObject = null;
            }

        } catch (ClientProtocolException e) {
            throw new CodeQualityMatricesException("ClientProtocolException when calling the REST API", e);

        } catch (IOException e) {
            throw new CodeQualityMatricesException("IOException occurred when calling the REST API", e);
        } finally {
            if (bufferedReader != null) {
                try {
                    bufferedReader.close();
                } catch (IOException e) {
                    throw new CodeQualityMatricesException("IOException occurred when closing the BufferedReader",
                            e);
                }
            }
            if (httpResponse != null) {
                try {
                    httpResponse.close();
                } catch (IOException e) {
                    throw new CodeQualityMatricesException("IOException occurred when closing the HttpResponse", e);
                }
            }
            if (httpclient != null) {
                try {
                    httpclient.close();
                } catch (IOException e) {
                    throw new CodeQualityMatricesException("IOException occurred when closing the HttpClient", e);
                }
            }
        }
        return returnedObject;
    }
}