「remember the milk API 用 Java クライアントを作る(1)」ブログ用

AuthUtil.java

package com.zaneli.rtm.model.util;

import java.util.HashMap;
import java.util.Map;

import com.zaneli.rtm.RtmException;

public class AuthUtil {

	private static final String URL = "http://www.rememberthemilk.com/services/auth/";

	public static String createAuthUrl(
			String apikey, String sharedSecret, Perms perms, String frob) throws RtmException {
		Map<String, String> params = new HashMap<String, String>();
		params.put("api_key", apikey);
		params.put("perms", perms.getValue());
		params.put("frob", frob);
		params.put("api_sig", RtmUtil.createApiSig(sharedSecret, params));
		return RtmUtil.createQueryUrl(URL, params);
	}

	public enum Perms {
		READ("read"), READ_WRITE("write"), ALL("delete");
		private final String value;
		private Perms(String value) {
			this.value = value;
		}
		public String getValue() {
			return value;
		}
	}

	private AuthUtil() {};
}

GetFrobResult.java

package com.zaneli.rtm.model;

public class GetFrobResult extends Result {

	public String getFrob() {
		return (String) getRsp().get("frob");
	}
}

GetTokenResult.java

package com.zaneli.rtm.model;

import java.util.Map;

public class GetTokenResult extends Result {

	public String getToken() {
		return (String) getAuth().get("token");
	}

	public String getPerms() {
		return (String) getAuth().get("perms");
	}

	public int getUserId() {
		return ((Integer) getUser().get("id")).intValue();
	}

	public int getUserName() {
		return ((Integer) getUser().get("username")).intValue();
	}

	public int getFullName() {
		return ((Integer) getUser().get("fullname")).intValue();
	}

	@SuppressWarnings("unchecked")
	private Map<String, Object> getAuth() {
		return (Map<String, Object>) getRsp().get("auth");
	}

	@SuppressWarnings("unchecked")
	private Map<String, Object> getUser() {
		return (Map<String, Object>) getAuth().get("user");
	}
}

Result.java

package com.zaneli.rtm.model;

import java.util.Map;

import org.apache.commons.lang3.builder.EqualsBuilder;
import org.apache.commons.lang3.builder.HashCodeBuilder;
import org.apache.commons.lang3.builder.ToStringBuilder;

import com.zaneli.rtm.RtmException;

public abstract class Result {

	private Map<String, Object> rsp;

	public String getStat() {
		return (String) getRsp().get("stat");
	}

	@SuppressWarnings("unchecked")
	public RtmException getErr() {
		return new RtmException((Map<String, Object>) rsp.get("err"));
	}

	public void setRsp(Map<String, Object> rsp) {
		this.rsp = rsp;
	}

	protected Map<String, Object> getRsp() {
		return rsp;
	}

	@Override
	public String toString() {
		return ToStringBuilder.reflectionToString(this);
	}

	@Override
	public boolean equals(Object obj) {
		return EqualsBuilder.reflectionEquals(this, obj);
	}

	@Override
	public int hashCode() {
		return HashCodeBuilder.reflectionHashCode(this);
	}
}

RtmClient.java

package com.zaneli.rtm;

import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import net.arnx.jsonic.JSON;

import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.client.methods.HttpRequestBase;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.protocol.HTTP;

import com.zaneli.rtm.model.GetFrobResult;
import com.zaneli.rtm.model.GetTokenResult;
import com.zaneli.rtm.model.Result;
import com.zaneli.rtm.model.util.RtmUtil;

public class RtmClient {

	private static final String URL = "https://api.rememberthemilk.com/services/rest/";

	private final String apikey;
	private final String sharedSecret;

	public RtmClient(String apikey, String sharedSecret) {
		this.apikey = apikey;
		this.sharedSecret = sharedSecret;
	}

	public GetFrobResult getFrob() throws RtmException, IOException {
		Map<String, String> params = new HashMap<String, String>();
		params.put("method", "rtm.auth.getFrob");
		params.put("api_key", apikey);
		params.put("format", "json");
		params.put("api_sig", RtmUtil.createApiSig(sharedSecret, params));
		
		HttpPost request = new HttpPost(URL);
		request.setEntity(createEntity(params));
		return execute(request, GetFrobResult.class);
	}

	public GetTokenResult getToken(String frob) throws RtmException, IOException {
		Map<String, String> params = new HashMap<String, String>();
		params.put("method", "rtm.auth.getToken");
		params.put("api_key", apikey);
		params.put("frob", frob);
		params.put("format", "json");
		params.put("api_sig", RtmUtil.createApiSig(sharedSecret, params));
		
		HttpPost request = new HttpPost(URL);
		request.setEntity(createEntity(params));
		return execute(request, GetTokenResult.class);
	}

	private <T extends Result> T execute(
			HttpRequestBase request,
			Class<? extends T> resultClass) throws IOException, RtmException {
		HttpClient httpClient = new DefaultHttpClient();
		HttpResponse response = httpClient.execute(request);
		
		InputStream in = null;
		try {
			in = response.getEntity().getContent();
			T result = JSON.decode(in, resultClass);
			String stat = result.getStat();
			if ("ok".equals(stat)) {
				return result;
			} else if ("fail".equals(stat)) {
				throw result.getErr();
			} else {
				throw new IllegalStateException("stat=" + stat);
			}
		} finally {
			if (in != null) in.close();
		}
	}

	private UrlEncodedFormEntity createEntity(Map<String, String> params) throws RtmException {
		List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
		for (Entry<String, String> entry : params.entrySet()) {
			nameValuePairs.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
		}
		try {
			return new UrlEncodedFormEntity(nameValuePairs, HTTP.UTF_8);
		} catch (UnsupportedEncodingException e) {
			throw new RtmException(e);
		}
	}
}

RtmException.java

package com.zaneli.rtm;

import java.util.Map;

@SuppressWarnings("serial")
public class RtmException extends Exception {

	public RtmException(Map<String, Object> errMap) {
		super("code=" + errMap.get("code") + ", msg=" + errMap.get("msg"));
	}

	public RtmException(Throwable cause) {
		super(cause);
	}
}

RtmUtil.java

package com.zaneli.rtm.model.util;

import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Map;
import java.util.Map.Entry;
import java.util.TreeMap;

import com.zaneli.rtm.RtmException;

public class RtmUtil {

	public static String createQueryUrl(String url, Map<String, String> queryParams) {
		StringBuilder sb = new StringBuilder(url);
		sb.append('?');
		for (Entry<String, String> entry : queryParams.entrySet()) {
			sb.append(entry.getKey()).append('=').append(entry.getValue()).append('&');
		}
		return sb.substring(0, sb.length() - 1).toString();
	}

	public static String createApiSig(String sharedSecret, Map<String, String> params) throws RtmException {
		Map<String, String> sortedParams = new TreeMap<String, String>(params);
		StringBuilder sb = new StringBuilder(sharedSecret);
		for (Entry<String, String> entry : sortedParams.entrySet()) {
			sb.append(entry.getKey());
			sb.append(entry.getValue());
		}
		try {
			return digest(sb.toString());
		} catch (NoSuchAlgorithmException e) {
			throw new RtmException(e);
		}
	}

	private static String digest(String value) throws NoSuchAlgorithmException {
		MessageDigest md = MessageDigest.getInstance("MD5");
		md.update(value.getBytes());
		return toHexString(md.digest());
	}

	private static String toHexString(byte[] byteArray) {
		StringBuilder sb = new StringBuilder();
		for (byte b : byteArray) {
			String hexStr = Integer.toHexString(b & 0xff);
			if (hexStr.length() == 1) {
				sb.append("0");
			}
			sb.append(hexStr);
		}
		return sb.toString();
	}

	private RtmUtil() {}
}