First basic draft version of a java client library. need feedback

contrib/JLightning/README.md

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+Draft version of the JLightning rpc interface for c-lightning.
+
+Using this client library is is as simple as the following code:
+```
+public static void main(String[] args) {
+	JLightningRpc rpc_interface = new JLightningRpc("/tmp/spark-env/ln1/lightning-rpc");
+	String res = rpc_interface.listInvoices(null);
+	System.out.println(res);
+	res = rpc_interface.listFunds();
+	System.out.println(res);
+}
+```
+
+This client library is provided and maintained by Rene Pickhardt

contrib/JLightning/src/de/renepickhardt/ln/JLightning.java

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+package de.renepickhardt.ln;
+
+/**
+ * JLightning a small test / example class to demonstrate how to use JLightningRpc
+ * 
+ * This file is basically a port of the pylightning python client library
+ * that comes with c-lightning.
+ * 
+ * The Author of this Java Client library is Rene Pickhardt. 
+ * He also holds the copyright of this file. The library is licensed with
+ * a BSD-style license. Have a look at the LICENSE file. 
+ * 
+ * If you like this library consider a donation via bitcoin or the lightning
+ * network at http://ln.rene-pickhardt.de
+ * 
+ * @author Rene Pickhardt
+
+ */
+
+public class JLightning {
+
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+
+		JLightningRpc rpc_interface = new JLightningRpc("/tmp/spark-env/ln1/lightning-rpc");
+		String res = rpc_interface.listInvoices(null);
+		System.out.println(res);
+		res = rpc_interface.listFunds();
+		System.out.println(res);
+		res = rpc_interface.listInvoices(null);
+		System.out.println(res);
+
+	}
+
+
+}

contrib/JLightning/src/de/renepickhardt/ln/JLightningRpc.java

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+package de.renepickhardt.ln;
+/**
+ * JLightningRpc extends the UnixDomainSocketRpc and exposes the specific 
+ * API that is provided by c-lightning. It  is a java client library for the 
+ * c-lightning node. It connects to c-lightning via a Unix Domain Socket over
+ * JsonRPC v2.0 
+ * 
+ * This file is basically a port of the pylightning python client library
+ * that comes with c-lightning.
+ * 
+ * The Author of this Java Client library is Rene Pickhardt. 
+ * He also holds the copyright of this file. The library is licensed with
+ * a BSD-style license. Have a look at the LICENSE file. 
+ * 
+ * If you like this library consider a donation via bitcoin or the lightning
+ * network at http://ln.rene-pickhardt.de
+ * 
+ * @author Rene Pickhardt
+ */
+
+import java.util.HashMap;
+
+
+
+public class JLightningRpc extends UnixDomainSocketRpc {
+
+	public JLightningRpc(String socket_path) {
+		super(socket_path);
+
+	}
+
+	/**
+	 * Delete unpaid invoice {label} with {status}
+	 * @param label of the invoice
+	 * @param status status of the invoice
+	 * @return
+	 */
+	public String delInvoice(String label, Status status) {
+		HashMap<String, String> payload = new HashMap<String,String> ();
+		payload.put("label", label);
+		payload.put("status", status.toString());
+		return this.call("delinvoice", payload);
+	}
+
+	public String getInfo() {
+		return this.call("getinfo", null);
+	}
+
+	/**
+	 * Show route to {id} for {msatoshi}, using {riskfactor} and optional
+     * {cltv} (default 9). If specified search from {fromid} otherwise use
+     * this node as source. Randomize the route with up to {fuzzpercent}
+     * (0.0 -> 100.0, default 5.0) using {seed} as an arbitrary-size string
+     * seed.
+	 * 
+	 * @param peer_id 
+	 * @param msatoshi
+	 * @param riskfactor
+	 * @param cltv
+	 * @param from_id
+	 * @param fuzzpercent
+	 * @param seed
+	 * @return
+	 */
+	public String getRoute(String peer_id, int msatoshi, float riskfactor, int cltv, String from_id, float fuzzpercent, String seed) {
+		HashMap<String, String> payload = new HashMap<String,String> ();
+		payload.put("id", peer_id);
+		payload.put("msatoshi", Integer.toString(msatoshi));
+		payload.put("riskfactor", Float.toString(riskfactor));
+		payload.put("cltv", Integer.toString(cltv));
+		payload.put("fromid", from_id);
+		payload.put("fuzzpercent", Float.toString(fuzzpercent));
+		payload.put("seed", seed);
+		return this.call("getroute", payload);
+	}
+
+	/**
+	 * Create an invoice for {msatoshi} with {label} and {description} with
+	 * optional {expiry} seconds (default 1 hour)
+	 * 
+	 * @param msatoshi
+	 * @param label
+	 * @param description
+	 * @param expiry
+	 * @param fallbacks
+	 * @param preimage
+	 * @return
+	 */
+	public String invoice (int msatoshi,String label, String description, int expiry,String fallbacks, String preimage) {		
+		HashMap<String, String> payload = new HashMap<String,String> ();
+		payload.put("msatoshi", Integer.toString(msatoshi));
+		payload.put("label", label);
+		payload.put("description", description);
+		payload.put("expiry", Integer.toString(expiry));
+		payload.put("fallbacks", fallbacks);
+		payload.put("preimage", preimage);
+		return this.call("invoice", payload);
+	}
+
+	/**
+	 * Show funds available for opening channels and open channels
+	 * @return
+	 */
+	public String listFunds() {
+		return this.call("listfunds", null);
+	}
+
+	/**
+	 * Show all known channels, accept optional {short_channel_id}
+	 */
+	public String listChannels(String short_channel_id) {		
+		HashMap<String, String> payload = new HashMap<String,String> ();
+		payload.put("short_channel_id", short_channel_id);
+		return this.call("listchannels", payload);
+	}	
+
+	/**
+	 * Show invoice {label} (or all, if no {label))
+	 * @param label for a specific invoice to look up
+	 * @return
+	 */
+	public String listInvoices(String label) {
+		HashMap<String, String> payload = new HashMap<String,String> ();
+		payload.put("label", label);
+		return this.call("listinvoices", payload);
+	}	
+
+	public String listNodes(String node_id) {
+		HashMap<String, String> payload = new HashMap<String,String> ();
+		payload.put("id", node_id);
+		return this.call("listnodes", payload);
+	}
+
+	/**
+	 * Wait for the next invoice to be paid, after {lastpay_index}
+     * (if supplied)
+	 * @param last_payindex
+	 * @return
+	 */
+	public String waitAnyInvoice(int last_payindex) {
+		HashMap<String, String> payload = new HashMap<String,String> ();
+		payload.put("last_pay_index", Integer.toString(last_payindex));
+		return this.call("waitanyinvoice", payload);
+	}
+
+
+}

contrib/JLightning/src/de/renepickhardt/ln/Status.java

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+package de.renepickhardt.ln;
+/**
+ * Named enum to encode the Status of invoices and payments
+ * 
+ * This file is basically a port of the pylightning python client library
+ * that comes with c-lightning.
+ * 
+ * The Author of this Java Client library is Rene Pickhardt. 
+ * He also holds the copyright of this file. The library is licensed with
+ * a BSD-style license. Have a look at the LICENSE file. 
+ * 
+ * If you like this library consider a donation via bitcoin or the lightning
+ * network at http://ln.rene-pickhardt.de
+ * 
+ * @author rpickhardt
+ */
+public enum Status {
+	PAID("paid"), UNPAID("unpaid"), EXPIRED("expired");
+
+	private final String statusDescription;
+
+    private Status(String value) {
+        statusDescription = value;
+    }
+
+    public String getStatusDescription() {
+        return statusDescription;
+    }
+}

contrib/JLightning/src/de/renepickhardt/ln/UnixDomainSocketRpc.java

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+package de.renepickhardt.ln;
+/**
+ * UnixDomainSocketRpc the base class to handle communication between
+ * JLightning and the c-lightning node over the UnixDomainSocket 
+ * 
+ * This file is basically a port of the pylightning python client library
+ * that comes with c-lightning.
+ * 
+ * The Author of this Java Client library is Rene Pickhardt. 
+ * He also holds the copyright of this file. The library is licensed with
+ * a BSD-style license. Have a look at the LICENSE file. 
+ * 
+ * If you like this library consider a donation via bitcoin or the lightning
+ * network at http://ln.rene-pickhardt.de
+ * 
+ * @author Rene Pickhardt
+ */
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStream;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Set;
+
+
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.newsclub.net.unix.AFUNIXSocket;
+import org.newsclub.net.unix.AFUNIXSocketAddress;
+
+public class UnixDomainSocketRpc {
+	protected AFUNIXSocket sock;
+	protected InputStream is;
+	protected OutputStream os;
+	protected static int id = 1;
+
+	public UnixDomainSocketRpc(String socket_path) {
+		File socketFile = new File(socket_path);
+		try {
+			this.sock = AFUNIXSocket.newInstance();
+			this.sock.connect(new AFUNIXSocketAddress(socketFile));
+			this.is = sock.getInputStream();
+			this.os = sock.getOutputStream();			
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+	}
+
+	public String call(String method, HashMap<String, String> payload) {
+		// if no payload is given make empty one
+		if(payload == null) {
+			payload = new HashMap<String, String>();
+		}
+
+		//remove null items from payload
+		Set<String> keySet = new HashSet<String>();
+		for (String key: payload.keySet()) {
+			keySet.add(key);
+		}
+		for(String k:keySet) {
+			if(payload.get(k)==null){
+				payload.remove(k);
+			}
+		}
+
+		JSONObject json = new JSONObject();
+
+		try {
+			json.put("method", method);
+			json.put("params", new JSONObject(payload));
+			// FIXME: Use id field to dispatch requests
+			json.put("id", Integer.toString(this.id++));
+		} catch (JSONException e) {
+			// TODO Auto-generated catch block
+			e.printStackTrace();
+		}
+
+		try {
+			this.os.write(json.toString().getBytes("UTF-8"));
+			this.os.flush();
+
+			// FIXME: Using a StringBuilder would be preferable but not so easy
+			String response = "";
+			int buffSize = 1024;
+			byte[] buf = new byte[buffSize];
+
+			while(true) { 
+				int read = this.is.read(buf);
+				response = response + new String(buf, 0, read, "UTF-8");
+				if(read <=0 || response.contains("\n\n" )) {
+					break;
+				}
+			}
+			json = new JSONObject(response);
+			if (json.has("result")) {
+				json = json.getJSONObject("result");
+				return json.toString(2);
+			}
+			else if (json.has("error")) {
+				json = json.getJSONObject("error");
+				return json.toString(2);
+			}
+			else
+				return "Could not Parse Response from Lightning Node: " + response;
+
+		} catch (IOException e) {
+			e.printStackTrace();
+			// FIXME: make json rpc? 
+			return "no Response from lightning node";
+		} catch (JSONException e) {
+			e.printStackTrace();
+			return "Could not parse response from Lightning Node";
+		}
+
+	}
+}