Use SRTM 1deg data from NASA servers

[GpsPrune.git] / src / tim / prune / function / srtm / SrtmGl1Source.java

diff --git a/src/tim/prune/function/srtm/SrtmGl1Source.java b/src/tim/prune/function/srtm/SrtmGl1Source.java
new file mode 100644 (file)
index 0000000..51e6d77
--- /dev/null
+++ b/src/tim/prune/function/srtm/SrtmGl1Source.java
@@ -0,0 +1,176 @@
+package tim.prune.function.srtm;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.CookieHandler;
+import java.net.CookieManager;
+import java.net.CookiePolicy;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.HttpURLConnection;
+
+import tim.prune.App;
+import tim.prune.GpsPrune;
+import tim.prune.config.Config;
+
+/**
+ * Create an account at: https://urs.earthdata.nasa.gov/users/new
+ * Data policy: https://lpdaac.usgs.gov/data/data-citation-and-policies/
+ *
+ */
+
+public class SrtmGl1Source extends SrtmSource {
+       /** URL prefix for all tiles */
+       private static final String URL_PREFIX = "https://e4ftl01.cr.usgs.gov/MEASURES/SRTMGL1.003/2000.02.11/";
+       /** Auth URL */
+       private static final String AUTH_URL = "urs.earthdata.nasa.gov";
+
+
+       public SrtmGl1Source()
+       {
+               CookieHandler.setDefault(new CookieManager(null, CookiePolicy.ACCEPT_ALL));
+       }
+
+       public String getName()
+       {
+               return "SRTMGL1_v003";
+       }
+
+       protected String getSourceExtension()
+       {
+               return ".SRTMGL1.hgt.zip";
+       }
+
+       private URL buildUrl(SrtmTile inTile)
+               throws SrtmSourceException
+       {
+               try {
+                       return new URL(URL_PREFIX + inTile.getTileName() + getSourceExtension());
+               }
+               catch (MalformedURLException e)
+               {
+                       throw new SrtmSourceException(e.getMessage());
+               }
+       }
+
+       public boolean isReadyToUse()
+       {
+               return getAuth() != null;
+       }
+
+       private String getAuth()
+       {
+               String authString = Config.getConfigString(Config.KEY_EARTHDATA_AUTH);
+               if (authString != null)
+               {
+                       return "Basic " + authString; 
+               }
+               else
+               {
+                       return null;
+               }
+       }
+
+       public boolean downloadTile(SrtmTile inTile)
+               throws SrtmSourceException
+       {
+               return downloadTile(inTile, getAuth());
+       }
+
+       private boolean downloadTile(SrtmTile inTile, String auth)
+               throws SrtmSourceException
+       {
+               URL tileUrl = buildUrl(inTile);
+               File outputFile = getCacheFileName(inTile);
+               System.out.println("Download: Need to download: " + tileUrl);
+               try
+               {
+                       HttpURLConnection conn = (HttpURLConnection) tileUrl.openConnection();
+                       long fileLength = 0L;
+
+                       // Define streams
+                       FileOutputStream outStream = null;
+                       InputStream inStream = null;
+
+                       // Documentation about HTTP interface at:
+                       // https://wiki.earthdata.nasa.gov/display/EL/How+To+Access+Data+With+Java
+                       int redirects = 0;
+
+                       while (redirects < 10) {
+                               redirects++;
+
+                               conn.setRequestProperty("User-Agent", "GpsPrune v" + GpsPrune.VERSION_NUMBER);
+                               conn.setInstanceFollowRedirects(false);
+                               conn.setUseCaches(false);
+                               if (conn.getURL().getHost().equals(AUTH_URL))
+                               {
+                                       conn.setRequestProperty("Authorization", auth);
+                               }
+
+                               int status = conn.getResponseCode();
+                               if (status == 200)
+                               {
+                                       // Found the tile, we're good
+                                       inStream = conn.getInputStream();
+                                       fileLength = conn.getContentLengthLong();
+                                       break;
+                               }
+                               else if (status == 302)
+                               {
+                                       // redirected to SSO server then back to original resource
+                                       String newUrl = conn.getHeaderField("Location");
+                                       conn = (HttpURLConnection) (new URL(newUrl)).openConnection();
+                               }
+                               else if (status == 404)
+                               {
+                                       throw new SrtmSourceException("Tile " + inTile.getTileName() + " not found at " + conn.getURL());
+                               }
+                               else
+                               {
+                                       throw new SrtmSourceException("Invalid response from server: " + status + conn.getResponseMessage());
+                               }
+                       }
+
+                       // _progress.setValue(t * 10 + 1);
+                       outStream = new FileOutputStream(outputFile);
+
+                       // Copy all the bytes to the file
+                       int c;
+                       long written = 0L;
+                       while ((c = inStream.read()) != -1)
+                       {
+                               outStream.write(c);
+                               written++;
+                               // _progress.setValue(t * 10 + 1 + (int) ((10 * written) / fileLength));
+                       }
+                       // Make sure streams are closed
+                       try {inStream.close();} catch (Exception e) {}
+                       try {outStream.close();} catch (Exception e) {}
+                       return true;
+               }
+               catch (IOException e)
+               {
+                       throw new SrtmSourceException("Error while downloading tile " + inTile.getTileName() + ": "+e.getMessage());
+               }
+       }
+
+       public boolean testAuth(String auth)
+               throws SrtmSourceException
+       {
+               // The only thing special about this tile is that it's the smallest tile
+               // It covers small islands in Malaysia
+               SrtmTile testTile = new SrtmTile(7, 117);
+               if (isCached(testTile))
+               {
+                       getCacheFileName(testTile).delete();
+               }
+               return downloadTile(testTile, auth);
+       }
+
+       public int getRowSize(SrtmTile inTile)
+       {
+               return 3601;
+       }
+}