separating repository access from processing

Author: retog

src/main/java/com/factsmission/psps/Repository.java

@@ -0,0 +1,148 @@
+/*
+ * The MIT License
+ *
+ * Copyright 2019 FactsMission AG.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package com.factsmission.psps;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.Reader;
+import java.net.HttpURLConnection;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.Base64;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+import org.json.simple.JSONArray;
+import org.json.simple.JSONObject;
+import org.json.simple.parser.JSONParser;
+import org.json.simple.parser.ParseException;
+
+/**
+ *
+ * @author me
+ */
+public class Repository {
+
+    private final String token;
+    private final String repository;
+    private String branch;
+    private final URL apiBaseURI;
+    private String latestCommitURL;
+    private Map<String, URL> path2Stuff;
+
+    Repository(String repository, String token) {
+        this.repository = repository;
+        this.token = token;
+        String apiBaseURIString = "https://api.github.com/repos/" + repository + "/";
+        try {
+            this.apiBaseURI = new URL(apiBaseURIString);
+        } catch (MalformedURLException ex) {
+            throw new RuntimeException(ex);
+        }
+    }
+    
+    InputStream getAuthenticatedStream(URL url) throws IOException {
+        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
+        String authStringEnoded = Base64.getEncoder().encodeToString((token + ":").getBytes("utf-8"));
+        connection.addRequestProperty("Authorization", "Basic " + authStringEnoded);
+        return connection.getInputStream();
+    }
+    
+    
+    private Object getParsedJson(URL stuffURL) throws IOException {
+        try {
+            InputStream stuffJsonStream = getAuthenticatedStream(stuffURL);
+            Reader stuffJsonReader = new InputStreamReader(stuffJsonStream, "utf-8");
+            JSONParser jsonParser = new JSONParser();
+            Object obj = jsonParser.parse(stuffJsonReader);
+            return obj;
+        } catch (ParseException ex) {
+            throw new RuntimeException(ex);
+        }
+    }
+
+    JSONObject getJsonObject(URL stuffURL) throws IOException {
+        return (JSONObject) getParsedJson(stuffURL);
+    }
+
+    JSONArray getJsonArray(URL stuffURL) throws IOException {
+        return (JSONArray) getParsedJson(stuffURL);
+    }
+
+    void useBranch(String branch) throws IOException {
+        this.branch = branch;
+        try {
+            URL masterURI = new URL(apiBaseURI, "branches/"+branch);
+            JSONObject master = getJsonObject(masterURI);
+            JSONObject commitA = (JSONObject) master.get("commit");
+            latestCommitURL = (String) commitA.get("html_url");
+            JSONObject commitB = (JSONObject) commitA.get("commit");
+            JSONObject tree = (JSONObject) commitB.get("tree");
+            String treeURLString = (String) tree.get("url");
+            processTree(treeURLString);
+        } catch (MalformedURLException | ParseException ex) {
+            throw new RuntimeException(ex);
+        }
+    }
+    
+    private void processTree(String treeURLString) throws IOException, ParseException {
+            String treeURLRecursiveString = treeURLString + "?recursive=1";
+            URL treeURLRecursive = new URL(treeURLRecursiveString);
+            JSONObject jsonObject = getJsonObject(treeURLRecursive);
+            JSONArray tree = (JSONArray) jsonObject.get("tree");
+            path2Stuff = new HashMap<>();
+            Iterator<JSONObject> iterator = tree.iterator();
+            while (iterator.hasNext()) {
+                JSONObject next = iterator.next();
+                String path = (String) next.get("path");
+                String url = (String) next.get("url");
+                URL stuffURL = new URL(url);
+                path2Stuff.put(path, stuffURL);
+            }
+            
+        }
+
+    String getCommitURL() {
+        return latestCommitURL;
+    }
+
+    Iterable<String> getPaths() {
+        return path2Stuff.keySet();
+    }
+
+    byte[] getContent(String path) throws IOException {
+        JSONObject jsonObject = getJsonObject(path2Stuff.get(path));
+        String contentBase64 = (String) jsonObject.get("content");
+        if (contentBase64 == null) {
+            return null;
+        }
+        try {
+            return Base64.getMimeDecoder().decode(contentBase64);                    
+        } catch (IllegalArgumentException ex) {
+            throw new RuntimeException("Something bad happened", ex);
+        }
+    }
+    
+}