D-Net

package eu.dnetlib.data.collector.plugins.doiresolver;

import eu.dnetlib.data.collector.plugins.HttpConnector;

import eu.dnetlib.data.collector.plugins.utils.JsonUtils;

import eu.dnetlib.data.collector.rmi.CollectorServiceException;

import org.apache.commons.io.IOUtils;

import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;

import org.springframework.beans.factory.annotation.Autowired;

import java.io.IOException;

import java.io.InputStream;

import java.util.regex.Pattern;

public class CrossrefResolver implements DOIResolver{

    private static final Log log = LogFactory.getLog(CrossrefResolver.class);

    private String baseURL = "https://api.crossref.org/works/";

    public static Pattern CROSSREF_DOI_REGEXP  = Pattern.compile("^10\\.\\d{4,9}/[-._;()/:A-Z0-9]+$", Pattern.CASE_INSENSITIVE);

    @Autowired

    private HttpConnector httpConnector;

    @Override

    public String resolve(String doi) {

        if(isValid(doi)) {

            try {

                InputStream is = httpConnector.getInputSourceAsStream(getBaseURL() + doi);

                return asXml(IOUtils.toString(is));

            } catch (IOException | CollectorServiceException e) {

                log.error("Cannot resolve doi " + doi + " Exception: " + e);

                return null;

            }

        }

        else {

            log.debug("Input does not look like a valid DOI " + doi);

            return null;

        }

    }

    protected boolean isValid(String doi){

        return CROSSREF_DOI_REGEXP.matcher(doi).matches();

    }

    protected String asXml(final String record){

       return new JsonUtils().convertToXML(record);

    }

    public String getBaseURL() {

        return baseURL;

    }

    public void setBaseURL(final String baseURL) {

        this.baseURL = baseURL;

    }

    public HttpConnector getHttpConnector() {

        return httpConnector;

    }

    public void setHttpConnector(HttpConnector httpConnector) {

        this.httpConnector = httpConnector;

    }

}