From 1002f328e2b216cc7e92b75eeaae5d2f89249fe5 Mon Sep 17 00:00:00 2001
From: Niki Roo <niki@nikiroo.be>
Date: Tue, 17 Sep 2019 08:18:34 +0200
Subject: [PATCH] Downloader: new offline mode

---
 changelog.md                         |  4 +++
 src/be/nikiroo/utils/Downloader.java | 38 +++++++++++++++++++++++++---
 2 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/changelog.md b/changelog.md
index e3852269..3fcdb762 100644
--- a/changelog.md
+++ b/changelog.md
@@ -1,5 +1,9 @@
 # nikiroo-utils
 
+## Version WIP
+
+- Downloader: new Offline mode for cache accesses only
+
 ## Version 5.0.0
 
 - new: server: count the bytes we rec/send
diff --git a/src/be/nikiroo/utils/Downloader.java b/src/be/nikiroo/utils/Downloader.java
index 2a462a81..b1ac56c0 100644
--- a/src/be/nikiroo/utils/Downloader.java
+++ b/src/be/nikiroo/utils/Downloader.java
@@ -30,6 +30,7 @@ public class Downloader {
 	private CookieManager cookies;
 	private TraceHandler tracer = new TraceHandler();
 	private Cache cache;
+	private boolean offline;
 
 	/**
 	 * Create a new {@link Downloader}.
@@ -63,6 +64,32 @@ public class Downloader {
 
 		setCache(cache);
 	}
+	
+	/**
+	 * This {@link Downloader} is forbidden to try and connect to the network.
+	 * <p>
+	 * If TRUE, it will only check the cache if any.
+	 * <p>
+	 * Default is FALSE.
+	 * 
+	 * @return TRUE if offline
+	 */
+	public boolean isOffline() {
+		return offline;
+	}
+	
+	/**
+	 * This {@link Downloader} is forbidden to try and connect to the network.
+	 * <p>
+	 * If TRUE, it will only check the cache if any.
+	 * <p>
+	 * Default is FALSE.
+	 * 
+	 * @param offline TRUE for offline, FALSE for online
+	 */
+	public void setOffline(boolean offline) {
+		this.offline = offline;
+	}
 
 	/**
 	 * The traces handler for this {@link Cache}.
@@ -167,7 +194,7 @@ public class Downloader {
 	 * @return the {@link InputStream} of the opened page
 	 * 
 	 * @throws IOException
-	 *             in case of I/O error
+	 *             in case of I/O error (including offline mode + not in cache)
 	 */
 	public InputStream open(URL url, URL currentReferer,
 			Map<String, String> cookiesValues, Map<String, String> postParams,
@@ -199,7 +226,7 @@ public class Downloader {
 	 * @return the {@link InputStream} of the opened page
 	 * 
 	 * @throws IOException
-	 *             in case of I/O error
+	 *             in case of I/O error (including offline mode + not in cache)
 	 */
 	public InputStream open(URL url, URL currentReferer,
 			Map<String, String> cookiesValues, Map<String, String> postParams,
@@ -236,7 +263,7 @@ public class Downloader {
 	 * @return the {@link InputStream} of the opened page
 	 * 
 	 * @throws IOException
-	 *             in case of I/O error
+	 *             in case of I/O error (including offline mode + not in cache)
 	 */
 	public InputStream open(URL url, final URL originalUrl, URL currentReferer,
 			Map<String, String> cookiesValues, Map<String, String> postParams,
@@ -254,6 +281,11 @@ public class Downloader {
 			}
 		}
 
+		if (offline) {
+			tracer.error("Downloader OFFLINE, cannot proceed to URL: " + url);
+			throw new IOException("Downloader is currently OFFLINE, cannot download: " + url);
+		}
+		
 		tracer.trace("Download: " + url);
 
 		URLConnection conn = openConnectionWithCookies(url, currentReferer,
-- 
2.27.0