Merge pull request #11 from databrickslabs/features/lint

Run linting for checkstyle

Author: nkvuong

.gitignore

@@ -203,4 +203,7 @@ Temporary Items
 .apdisk
 
 # Ignore docs/_build
-docs/_build
+docs/_build
+
+# VScode
+.vscode

src/main/java/io/delta/sharing/java/DeltaSharing.java

@@ -1,9 +1,8 @@
 package io.delta.sharing.java;
 
-import io.delta.sharing.java.adaptor.DeltaSharingJSONProvider;
+import io.delta.sharing.java.adaptor.DeltaSharingJsonProvider;
 import io.delta.sharing.spark.DeltaSharingProfileProvider;
 import io.delta.sharing.spark.DeltaSharingRestClient;
-
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -12,45 +11,51 @@
 import java.util.HashMap;
 
 /**
- * Factory class for {@link DeltaSharing}.
- * It provides different constructors that might be appropriate in different situations.
+ * Factory class for {@link DeltaSharing}. It provides different constructors that might be
+ * appropriate in different situations.
  */
 public class DeltaSharingFactory {
 
-    /**
-     * Constructor
-     * @param profileProvider An instance of {@link DeltaSharingProfileProvider}.
-     * @param checkpointPath An path to a temporary checkpoint location.
-     * @return An instance of {@link DeltaSharing} client.
-     * @throws IOException Transitive due to the call to {@link Files#createTempDirectory(String, FileAttribute[])}.
-     */
-    public static DeltaSharing create(DeltaSharingProfileProvider profileProvider, Path checkpointPath) throws IOException {
-        DeltaSharing instance = new DeltaSharing();
-        instance.profileProvider = profileProvider;
-        instance.httpClient = new DeltaSharingRestClient(profileProvider, 120, 4, false);
-        instance.checkpointPath = checkpointPath;
-        instance.metadataMap = new HashMap<>();
-        if (!Files.exists(checkpointPath)) {
-            Files.createDirectory(instance.checkpointPath);
-        }
-        instance.tempDir = Files.createTempDirectory(instance.checkpointPath, "delta_sharing");
-        instance.tempDir.toFile().deleteOnExit();
-        return instance;
+  /**
+   * Constructor.
+   *
+   * @param profileProvider An instance of {@link DeltaSharingProfileProvider}.
+   * @param checkpointPath An path to a temporary checkpoint location.
+   * @return An instance of {@link DeltaSharing} client.
+   * @throws IOException Transitive due to the call to
+   *         {@link Files#createTempDirectory(String, FileAttribute[])}.
+   */
+  public static DeltaSharing create(DeltaSharingProfileProvider profileProvider,
+      Path checkpointPath) throws IOException {
+    DeltaSharing instance = new DeltaSharing();
+    instance.profileProvider = profileProvider;
+    instance.httpClient = new DeltaSharingRestClient(profileProvider, 120, 4, false);
+    instance.checkpointPath = checkpointPath;
+    instance.metadataMap = new HashMap<>();
+    if (!Files.exists(checkpointPath)) {
+      Files.createDirectory(instance.checkpointPath);
     }
+    instance.tempDir = Files.createTempDirectory(instance.checkpointPath, "delta_sharing");
+    instance.tempDir.toFile().deleteOnExit();
+    return instance;
+  }
 
-    /**
-     * Constructor
-     * @param providerConf A valid JSON document corresponding to {@link DeltaSharingProfileProvider}.
-     * @param checkpointLocation A string containing a path to be used as a checkpoint location.
-     * @return An instance of {@link DeltaSharing} client.
-     * @throws IOException Transitive due to the call to {@link Files#createDirectories(Path, FileAttribute[])}.
-     */
-    public static DeltaSharing create(String providerConf, String checkpointLocation) throws IOException {
-        Path checkpointPath = Paths.get(checkpointLocation);
-        if(!Files.exists(checkpointPath)){
-            Files.createDirectories(checkpointPath);
-        }
-        DeltaSharingProfileProvider profileProvider = new DeltaSharingJSONProvider(providerConf);
-        return create(profileProvider, checkpointPath);
+  /**
+   * Constructor.
+   *
+   * @param providerConf A valid JSON document corresponding to {@link DeltaSharingProfileProvider}.
+   * @param checkpointLocation A string containing a path to be used as a checkpoint location.
+   * @return An instance of {@link DeltaSharing} client.
+   * @throws IOException Transitive due to the call to
+   *         {@link Files#createDirectories(Path, FileAttribute[])}.
+   */
+  public static DeltaSharing create(String providerConf, String checkpointLocation)
+      throws IOException {
+    Path checkpointPath = Paths.get(checkpointLocation);
+    if (!Files.exists(checkpointPath)) {
+      Files.createDirectories(checkpointPath);
     }
+    DeltaSharingProfileProvider profileProvider = new DeltaSharingJsonProvider(providerConf);
+    return create(profileProvider, checkpointPath);
+  }
 }

src/main/java/io/delta/sharing/java/DeltaSharingFactory.java

@@ -0,0 +1,60 @@
+package io.delta.sharing.java.adaptor;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import io.delta.sharing.spark.DeltaSharingProfile;
+import io.delta.sharing.spark.DeltaSharingProfileProvider;
+
+
+/**
+ * Loads {@link io.delta.sharing.spark.DeltaSharingProfileProvider} based on configuration provided
+ * as a JSON document. JSON document has to be a valid profile file document. Required fields are
+ * checked inside the constructor method and the object creation will fail in case of breaking the
+ * constraints.
+ * <p/>
+ *
+ * @author Milos Colic
+ * @see DeltaSharingProfileAdaptor DeltaSharingProfileAdaptor used for object mapping when parsing
+ *      JSON.
+ * @since 0.1.0
+ */
+public class DeltaSharingJsonProvider implements DeltaSharingProfileProvider {
+  String configuration;
+  DeltaSharingProfile profile;
+
+  /**
+   * Constructor method that expects Configuration JSON. JSON file must contain endpoint,
+   * bearerToken and shareCredentialsVersion fields. Object creation will fail if
+   * shareCredentialsVersion is too new.
+   *
+   * @param conf A valid JSON object.
+   */
+  public DeltaSharingJsonProvider(String conf) throws JsonProcessingException {
+    try {
+      configuration = conf;
+      ObjectMapper mapper = new ObjectMapper();
+      DeltaSharingProfileAdaptor profileAdaptor =
+          mapper.readValue(configuration, DeltaSharingProfileAdaptor.class);
+      profile = profileAdaptor.toProfile();
+    } catch (Exception e) {
+      System.out.print(e);
+      throw e;
+    }
+
+    if ((int) profile.shareCredentialsVersion().get() > DeltaSharingProfile.CURRENT()) {
+      throw new IllegalArgumentException("'shareCredentialsVersion' in the profile is "
+          + "${profile.shareCredentialsVersion.get} which is too new. The current release "
+          + "supports version ${DeltaSharingProfile.CURRENT} and below. Please upgrade to a newer "
+          + "release.");
+    }
+    if (profile.endpoint() == null) {
+      throw new IllegalArgumentException("Cannot find the 'endpoint' field in the profile file");
+    }
+  }
+
+
+  @Override
+  public DeltaSharingProfile getProfile() {
+    return profile;
+  }
+}

src/main/java/io/delta/sharing/java/adaptor/DeltaSharingJSONProvider.java

@@ -4,70 +4,73 @@
 import scala.Option;
 
 /**
- * Used for Jackson JSON parsing and object mapping.
- * POJO corresponding to profile file format.
+ * Used for Jackson JSON parsing and object mapping. POJO corresponding to profile file format.
  * Update when the format of profile file changes.
- * @implNote Suppress is added because of all the getters and setters are required to be explicitly created for Jackson
- * to parse JSONs correctly. However warnings are shown since getters and setters are not explicitly tests.
- * @author      Milos Colic
- * @since       0.1.0
+ *
+ * @implNote Suppress is added because of all the getters and setters are required to be explicitly
+ *           created for Jackson to parse JSONs correctly. However warnings are shown since getters
+ *           and setters are not explicitly tests.
+ * @author Milos Colic
+ * @since 0.1.0
  */
-@SuppressWarnings("unused")
 public class DeltaSharingProfileAdaptor {
-    int shareCredentialsVersion;
-    String endpoint;
-    String bearerToken;
-    String expirationTime;
+  int shareCredentialsVersion;
+  String endpoint;
+  String bearerToken;
+  String expirationTime;
 
-    /** Default constructor. */
-    public DeltaSharingProfileAdaptor() { }
+  /** Default constructor. */
+  public DeltaSharingProfileAdaptor() {}
 
-    /** Getter for shareCredentialsVersion. */
-    public int getShareCredentialsVersion() {
-        return shareCredentialsVersion;
-    }
+  /** Getter for shareCredentialsVersion. */
+  public int getShareCredentialsVersion() {
+    return shareCredentialsVersion;
+  }
 
-    /** Setter for shareCredentialsVersion. */
-    public void setShareCredentialsVersion(int shareCredentialsVersion) {
-        this.shareCredentialsVersion = shareCredentialsVersion;
-    }
+  /** Setter for shareCredentialsVersion. */
+  public void setShareCredentialsVersion(int shareCredentialsVersion) {
+    this.shareCredentialsVersion = shareCredentialsVersion;
+  }
 
-    /** Getter for endpoint. */
-    public String getEndpoint() {
-        return endpoint;
-    }
+  /** Getter for endpoint. */
+  public String getEndpoint() {
+    return endpoint;
+  }
 
-    /** Setter for endpoint. */
-    public void setEndpoint(String endpoint) {
-        this.endpoint = endpoint;
-    }
+  /** Setter for endpoint. */
+  public void setEndpoint(String endpoint) {
+    this.endpoint = endpoint;
+  }
 
-    /** Getter for bearerToken. */
-    public String getBearerToken() {
-        return bearerToken;
-    }
+  /** Getter for bearerToken. */
+  public String getBearerToken() {
+    return bearerToken;
+  }
 
-    /** Setter for bearerToken. */
-    public void setBearerToken(String bearerToken) {
-        this.bearerToken = bearerToken;
-    }
+  /** Setter for bearerToken. */
+  public void setBearerToken(String bearerToken) {
+    this.bearerToken = bearerToken;
+  }
 
-    /** Getter for expirationTime. */
-    public String getExpirationTime() {
-        return expirationTime;
-    }
+  /** Getter for expirationTime. */
+  public String getExpirationTime() {
+    return expirationTime;
+  }
 
-    /** Setter for expirationTime. */
-    public void setExpirationTime(String expirationTime) {
-        this.expirationTime = expirationTime;
-    }
+  /** Setter for expirationTime. */
+  public void setExpirationTime(String expirationTime) {
+    this.expirationTime = expirationTime;
+  }
 
-    /**
-     * Java wrapper method that can generate Scala paired object.
-     * This is need to be able to abstract from cross language APIs.
-     * @return An equivalent instance of Scala {@link io.delta.sharing.spark.DeltaSharingProfile} class.
-     */
-    public DeltaSharingProfile toProfile() {
-        return DeltaSharingProfile.apply(Option.apply(shareCredentialsVersion), endpoint, bearerToken, expirationTime);
-    }
+  /**
+   * Java wrapper method that can generate Scala paired object. This is need to be able to abstract
+   * from cross language APIs.
+   *
+   * @return An equivalent instance of Scala {@link io.delta.sharing.spark.DeltaSharingProfile}
+   *         class.
+   */
+  public DeltaSharingProfile toProfile() {
+    return DeltaSharingProfile.apply(Option.apply(shareCredentialsVersion), endpoint, bearerToken,
+        expirationTime);
+  }
 }