[feat] starting idf mobilite extractor

pom.xml

@@ -23,6 +23,11 @@
 			<artifactId>junit-jupiter</artifactId>
 			<version>5.9.1</version>
 		</dependency>
+		<dependency>
+			<groupId>com.opencsv</groupId>
+			<artifactId>opencsv</artifactId>
+			<version>5.4</version>
+		</dependency>
 	</dependencies>
 
 	<build>

src/main/java/fr/u_paris/gla/project/idfm/IDFMNetworkExtractor.java

@@ -0,0 +1,79 @@
+/**
+ * 
+ */
+package fr.u_paris.gla.project.idfm;
+
+import java.io.BufferedReader;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.io.Reader;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.util.function.Consumer;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import com.opencsv.CSVParserBuilder;
+import com.opencsv.CSVReader;
+import com.opencsv.CSVReaderBuilder;
+import com.opencsv.CSVWriterBuilder;
+import com.opencsv.ICSVParser;
+import com.opencsv.ICSVWriter;
+import com.opencsv.exceptions.CsvValidationException;
+
+/** Code of an extractor for the data from IDF mobilite.
+ * 
+ * @author Emmanuel Bigeon */
+public class IDFMNetworkExtractor {
+    /** The logger for information on the process */
+    private static final Logger LOGGER = Logger
+            .getLogger(IDFMNetworkExtractor.class.getName());
+
+    // IDF mobilite API URLs
+    private static final String TRACE_FILE_URL = "https://data.iledefrance-mobilites.fr/api/explore/v2.1/catalog/datasets/traces-des-lignes-de-transport-en-commun-idfm/exports/csv?lang=fr&timezone=Europe%2FBerlin&use_labels=true&delimiter=%3B";
+    private static final String STOPS_FILE_URL = "https://data.iledefrance-mobilites.fr/api/explore/v2.1/catalog/datasets/arrets-lignes/exports/csv?lang=fr&timezone=Europe%2FBerlin&use_labels=true&delimiter=%3B";
+
+    public static void readCSVFromURL(String url, Consumer<String[]> contentLineConsumer)
+            throws IOException {
+        ICSVParser parser = new CSVParserBuilder().withSeparator(';').build();
+        try (InputStream is = new URL(url).openStream();
+                Reader reader = new BufferedReader(
+                        new InputStreamReader(is, StandardCharsets.UTF_8))) {
+            CSVReaderBuilder csvBuilder = new CSVReaderBuilder(reader)
+                    .withCSVParser(parser);
+            try (CSVReader csv = csvBuilder.build()) {
+                String[] line = csv.readNextSilently(); // Eliminate header
+                while (csv.peek() != null) {
+                    line = csv.readNext();
+                    contentLineConsumer.accept(line);
+                }
+            }
+        } catch (CsvValidationException e) {
+            throw new IOException("Invalid csv file for lines", e);
+        }
+    }
+
+    /** Main entry point for the extractor of IDF mobilite data into a network as
+     * defined by this application.
+     * 
+     * @param args the arguments (expected one for the destination file) */
+    public static void main(String[] args) {
+
+        if (args.length != 1) {
+            LOGGER.severe("Invalid command line. Missing target file.");
+            return;
+        }
+
+        // Export content in required format
+        try (FileWriter writer = new FileWriter(args[0], StandardCharsets.UTF_8)) {
+            CSVWriterBuilder wBuilder = new CSVWriterBuilder(writer).withSeparator(';');
+            try (ICSVWriter csv = wBuilder.build()) {
+                // TODO write the content
+            }
+        } catch (IOException e) {
+            LOGGER.log(Level.SEVERE, e, () -> "Could not write in file " + args[1]);
+        }
+    }
+}