#9: Initial implementation of Streaming and reading of resources thro…

…ugh a table schema with cast on iteration.

pom.xml

@@ -75,5 +75,13 @@
             <artifactId>commons-lang3</artifactId>
             <version>3.6</version>
         </dependency>
+
+        <!-- Commons CSV: https://commons.apache.org/proper/commons-csv/ -->
+        <dependency>
+            <groupId>org.apache.commons</groupId>
+            <artifactId>commons-csv</artifactId>
+            <version>1.5</version>
+        </dependency>
+
     </dependencies>
 </project>

src/main/java/io/frictionlessdata/datapackage/Profile.java

@@ -0,0 +1,11 @@
+package io.frictionlessdata.datapackage;
+
+/**
+ *
+ * 
+ */
+public class Profile {
+    public final static String PROFILE_DEFAULT = "data-package";
+    public static final String PROFILE_TABULAR_DATA_RESOURCE = "tabular-data-resource";
+
+}

src/main/java/io/frictionlessdata/datapackage/Resource.java

@@ -0,0 +1,107 @@
+package io.frictionlessdata.datapackage;
+
+import io.frictionlessdata.datapackage.exceptions.DataPackageException;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.IOException;
+import java.io.Reader;
+import org.apache.commons.csv.CSVFormat;
+import org.apache.commons.csv.CSVRecord;
+
+/**
+ * Resource.
+ * Based on specs: http://frictionlessdata.io/specs/data-resource/
+ */
+public class Resource {
+
+    // Data properties.
+    private String path = null;
+    private Object data = null;
+
+    // Metadata properties.
+    // Required properties.
+    private String name = null;
+
+    // Recommended properties.
+    private String profile = null;
+
+    // Optional properties.
+    private String title = null;
+    private String description = null;
+    private String format = null;
+    private String mediaType = null;
+    private String encoding = null;
+    private Integer bytes = null;
+    private String hash = null;
+
+    // hashes and licenes?
+
+    public Resource(String name, String path){
+        this.name = name;
+        this.path = path;
+    }
+
+    public Resource(String name, Object data, String format){
+        this.name = name;
+        this.data = data;
+        this.format = format;
+    }
+
+    public Iterable<CSVRecord> iter() throws IOException, FileNotFoundException, DataPackageException{
+        // Error for non tabular
+        if(this.profile.equalsIgnoreCase(Profile.PROFILE_TABULAR_DATA_RESOURCE)){
+            throw new DataPackageException("Unsupported for non tabular data.");
+        }
+
+        if(this.path != null){
+            Reader in = new FileReader(this.path);
+            Iterable<CSVRecord> csvRecords = CSVFormat.RFC4180.parse(in);
+
+            return csvRecords;
+
+        }else if (this.data != null){
+            return null;
+
+        }else{
+            throw new DataPackageException("No data has been set.");
+        }
+    }
+
+    public void read() throws DataPackageException{
+        if(this.profile.equalsIgnoreCase(Profile.PROFILE_TABULAR_DATA_RESOURCE)){
+            throw new DataPackageException("Unsupported for non tabular data.");
+        }
+
+        if(path != null){
+
+        }else if (data != null){
+
+        }else{
+            throw new DataPackageException("No data has been set.");
+        }
+    }
+
+    public String getProfile(){
+        return this.profile;
+    }
+
+    public void setProfile(String profile){
+        this.profile = profile;
+    }
+
+    public String getTitle(){
+        return this.title;
+    }
+
+    public void setTitle(String title){
+        this.title = title;
+    }
+
+    public String getDescription(){
+        return this.description;
+    }
+
+    public void setDescription(String description){
+        this.description = description;
+    }
+}

src/main/java/io/frictionlessdata/datapackage/Validator.java

@@ -17,7 +17,7 @@
  */
 public class Validator {
 
-    private final static String PROFILE_DEFAULT = "data-package";
+
 
     /**
      * Validates a given JSON Object against the default profile schema.
@@ -43,7 +43,7 @@ public void validate(JSONObject datapackageJsonObject) throws IOException, DataP
 
         }else{
             // If no profile value is provided, use default value.
-            this.validate(datapackageJsonObject, PROFILE_DEFAULT);
+            this.validate(datapackageJsonObject, Profile.PROFILE_DEFAULT);
         }   
     }
 

src/test/java/io/frictionlessdata/datapackage/ResourceTest.java

@@ -0,0 +1,54 @@
+package io.frictionlessdata.datapackage;
+
+import io.frictionlessdata.datapackage.exceptions.DataPackageException;
+import java.io.IOException;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.List;
+import org.apache.commons.csv.CSVRecord;
+import org.junit.Assert;
+import org.junit.Test;
+
+/**
+ *
+ * 
+ */
+public class ResourceTest {
+
+    @Test
+    public void testValidationWithValidProfileUrl() throws IOException, DataPackageException, MalformedURLException{
+
+        URL url = new URL("https://raw.githubusercontent.com/frictionlessdata/datapackage-java/master/src/test/resources/fixtures/valid_population_datapackage.json");
+        Resource resource = new Resource("population", url, "csv");
+
+        // Set the profile to tabular data resource.
+        resource.setProfile(Profile.PROFILE_TABULAR_DATA_RESOURCE);
+
+        // Expected data.
+        List<String[]> expectedData = new ArrayList();
+        expectedData.add(new String[]{"city", "year", "population"});
+        expectedData.add(new String[]{"london", "2017", "8780000"});
+        expectedData.add(new String[]{"paris", "2017", "2240000"});
+        expectedData.add(new String[]{"rome", "2017", "2860000"});
+
+        // Get iterator.
+        Iterable<CSVRecord> records = resource.iter();
+        int expectedDataIndex = 0;
+
+        // Assert data.
+        for (CSVRecord record : records) {
+            String city = record.get(0);
+            String year = record.get(1);
+            String population = record.get(2);
+
+            Assert.assertEquals(expectedData.get(expectedDataIndex)[0], city);
+            Assert.assertEquals(expectedData.get(expectedDataIndex)[1], year);
+            Assert.assertEquals(expectedData.get(expectedDataIndex)[2], population);
+
+            expectedDataIndex++;
+        }
+
+    }
+
+}

src/test/resources/fixtures/data/area.csv

@@ -1,4 +1,4 @@
-city,year,population
-london,2017,8780000
-paris,2017,2240000
-rome,2017,2860000
+city,year,area_km2
+london,2017,1572
+paris,2017,105.4
+rome,2017,1285

src/test/resources/fixtures/data/population.csv

@@ -1,4 +1,4 @@
-city,year,area_km2
-london,2017,1572
-paris,2017,105.4
-rome,2017,1285
+city,year,population
+london,2017,8780000
+paris,2017,2240000
+rome,2017,2860000

src/test/resources/fixtures/valid_population_datapackage.json

@@ -0,0 +1,17 @@
+{
+    "name": "world",
+    "resources": [
+      {
+        "name": "population",
+        "path": "data/population.csv",
+        "profile":"tabular-data-resource",
+        "schema": {
+          "fields": [
+            {"name": "city", "type": "string"},
+            {"name": "year", "type": "integer"},
+            {"name": "population", "type": "integer"}
+          ]
+        }
+      }
+    ]
+}