From b9458f47e9550901ed6c1f852b7960d0ea44915c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20Pfeuffer?= <rene.pfeuffer@cloudogu.com>
Date: Tue, 20 Nov 2018 11:04:30 +0100
Subject: [PATCH 1/5] Add support for custom violation exceptions

---
 .../scm/ScmConstraintViolationException.java  | 76 +++++++++++++++++++
 ...=> ResteasyValidationExceptionMapper.java} |  8 +-
 ...cmConstraintValidationExceptionMapper.java | 30 ++++++++
 .../scm/api/v2/resources/MapperModule.java    |  3 +-
 ...syViolationExceptionToErrorDtoMapper.java} |  2 +-
 ...ScmViolationExceptionToErrorDtoMapper.java | 53 +++++++++++++
 6 files changed, 166 insertions(+), 6 deletions(-)
 create mode 100644 scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
 rename scm-webapp/src/main/java/sonia/scm/api/v2/{ValidationExceptionMapper.java => ResteasyValidationExceptionMapper.java} (62%)
 create mode 100644 scm-webapp/src/main/java/sonia/scm/api/v2/ScmConstraintValidationExceptionMapper.java
 rename scm-webapp/src/main/java/sonia/scm/api/v2/resources/{ViolationExceptionToErrorDtoMapper.java => ResteasyViolationExceptionToErrorDtoMapper.java} (96%)
 create mode 100644 scm-webapp/src/main/java/sonia/scm/api/v2/resources/ScmViolationExceptionToErrorDtoMapper.java

diff --git a/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java b/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
new file mode 100644
index 0000000000..1fb31dc0fc
--- /dev/null
+++ b/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
@@ -0,0 +1,76 @@
+package sonia.scm;
+
+import java.util.ArrayList;
+import java.util.Collection;
+
+import static java.util.Collections.unmodifiableCollection;
+
+public class ScmConstraintViolationException extends RuntimeException {
+
+  private final Collection<ScmConstraintViolation> violations;
+
+  private final String furtherInformations;
+
+  private ScmConstraintViolationException(Collection<ScmConstraintViolation> violations, String furtherInformations) {
+    this.violations = violations;
+    this.furtherInformations = furtherInformations;
+  }
+
+  public Collection<ScmConstraintViolation> getViolations() {
+    return unmodifiableCollection(violations);
+  }
+
+  public String getUrl() {
+    return furtherInformations;
+  }
+
+  public static class Builder {
+    private final Collection<ScmConstraintViolation> violations = new ArrayList<>();
+    private String furtherInformations;
+
+    public static Builder doThrow() {
+      Builder builder = new Builder();
+      return builder;
+    }
+
+    public Builder andThrow() {
+      this.violations.clear();
+      this.furtherInformations = null;
+      return this;
+    }
+
+    public Builder violation(String message, String... pathElements) {
+      this.violations.add(new ScmConstraintViolation(message, pathElements));
+      return this;
+    }
+
+    public Builder withFurtherInformations(String furtherInformations) {
+      this.furtherInformations = furtherInformations;
+      return this;
+    }
+
+    public void when(boolean condition) {
+      if (condition && !this.violations.isEmpty()) {
+        throw new ScmConstraintViolationException(violations, furtherInformations);
+      }
+    }
+  }
+
+  public static class ScmConstraintViolation {
+    private final String message;
+    private final String path;
+
+    private ScmConstraintViolation(String message, String... pathElements) {
+      this.message = message;
+      this.path = String.join(".", pathElements);
+    }
+
+    public String getMessage() {
+      return message;
+    }
+
+    public String getPropertyPath() {
+      return path;
+    }
+  }
+}
diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/ValidationExceptionMapper.java b/scm-webapp/src/main/java/sonia/scm/api/v2/ResteasyValidationExceptionMapper.java
similarity index 62%
rename from scm-webapp/src/main/java/sonia/scm/api/v2/ValidationExceptionMapper.java
rename to scm-webapp/src/main/java/sonia/scm/api/v2/ResteasyValidationExceptionMapper.java
index 6fadce8500..63582e10b8 100644
--- a/scm-webapp/src/main/java/sonia/scm/api/v2/ValidationExceptionMapper.java
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/ResteasyValidationExceptionMapper.java
@@ -1,7 +1,7 @@
 package sonia.scm.api.v2;
 
 import org.jboss.resteasy.api.validation.ResteasyViolationException;
-import sonia.scm.api.v2.resources.ViolationExceptionToErrorDtoMapper;
+import sonia.scm.api.v2.resources.ResteasyViolationExceptionToErrorDtoMapper;
 
 import javax.inject.Inject;
 import javax.ws.rs.core.MediaType;
@@ -10,12 +10,12 @@ import javax.ws.rs.ext.ExceptionMapper;
 import javax.ws.rs.ext.Provider;
 
 @Provider
-public class ValidationExceptionMapper implements ExceptionMapper<ResteasyViolationException> {
+public class ResteasyValidationExceptionMapper implements ExceptionMapper<ResteasyViolationException> {
 
-  private final ViolationExceptionToErrorDtoMapper mapper;
+  private final ResteasyViolationExceptionToErrorDtoMapper mapper;
 
   @Inject
-  public ValidationExceptionMapper(ViolationExceptionToErrorDtoMapper mapper) {
+  public ResteasyValidationExceptionMapper(ResteasyViolationExceptionToErrorDtoMapper mapper) {
     this.mapper = mapper;
   }
 
diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/ScmConstraintValidationExceptionMapper.java b/scm-webapp/src/main/java/sonia/scm/api/v2/ScmConstraintValidationExceptionMapper.java
new file mode 100644
index 0000000000..991aeedaeb
--- /dev/null
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/ScmConstraintValidationExceptionMapper.java
@@ -0,0 +1,30 @@
+package sonia.scm.api.v2;
+
+import sonia.scm.ScmConstraintViolationException;
+import sonia.scm.api.v2.resources.ScmViolationExceptionToErrorDtoMapper;
+
+import javax.inject.Inject;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.Response;
+import javax.ws.rs.ext.ExceptionMapper;
+import javax.ws.rs.ext.Provider;
+
+@Provider
+public class ScmConstraintValidationExceptionMapper implements ExceptionMapper<ScmConstraintViolationException> {
+
+  private final ScmViolationExceptionToErrorDtoMapper mapper;
+
+  @Inject
+  public ScmConstraintValidationExceptionMapper(ScmViolationExceptionToErrorDtoMapper mapper) {
+    this.mapper = mapper;
+  }
+
+  @Override
+  public Response toResponse(ScmConstraintViolationException exception) {
+    return Response
+      .status(Response.Status.BAD_REQUEST)
+      .type(MediaType.APPLICATION_JSON_TYPE)
+      .entity(mapper.map(exception))
+      .build();
+  }
+}
diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/MapperModule.java b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/MapperModule.java
index 35f58cef90..e6cf6721a5 100644
--- a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/MapperModule.java
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/MapperModule.java
@@ -39,7 +39,8 @@ public class MapperModule extends AbstractModule {
 
     bind(ReducedObjectModelToDtoMapper.class).to(Mappers.getMapper(ReducedObjectModelToDtoMapper.class).getClass());
 
-    bind(ViolationExceptionToErrorDtoMapper.class).to(Mappers.getMapper(ViolationExceptionToErrorDtoMapper.class).getClass());
+    bind(ResteasyViolationExceptionToErrorDtoMapper.class).to(Mappers.getMapper(ResteasyViolationExceptionToErrorDtoMapper.class).getClass());
+    bind(ScmViolationExceptionToErrorDtoMapper.class).to(Mappers.getMapper(ScmViolationExceptionToErrorDtoMapper.class).getClass());
     bind(ExceptionWithContextToErrorDtoMapper.class).to(Mappers.getMapper(ExceptionWithContextToErrorDtoMapper.class).getClass());
 
     // no mapstruct required
diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/ViolationExceptionToErrorDtoMapper.java b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/ResteasyViolationExceptionToErrorDtoMapper.java
similarity index 96%
rename from scm-webapp/src/main/java/sonia/scm/api/v2/resources/ViolationExceptionToErrorDtoMapper.java
rename to scm-webapp/src/main/java/sonia/scm/api/v2/resources/ResteasyViolationExceptionToErrorDtoMapper.java
index e713b031f7..7bab2d4272 100644
--- a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/ViolationExceptionToErrorDtoMapper.java
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/ResteasyViolationExceptionToErrorDtoMapper.java
@@ -12,7 +12,7 @@ import java.util.List;
 import java.util.stream.Collectors;
 
 @Mapper
-public abstract class ViolationExceptionToErrorDtoMapper {
+public abstract class ResteasyViolationExceptionToErrorDtoMapper {
 
   @Mapping(target = "errorCode", ignore = true)
   @Mapping(target = "transactionId", ignore = true)
diff --git a/scm-webapp/src/main/java/sonia/scm/api/v2/resources/ScmViolationExceptionToErrorDtoMapper.java b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/ScmViolationExceptionToErrorDtoMapper.java
new file mode 100644
index 0000000000..3828134cc1
--- /dev/null
+++ b/scm-webapp/src/main/java/sonia/scm/api/v2/resources/ScmViolationExceptionToErrorDtoMapper.java
@@ -0,0 +1,53 @@
+package sonia.scm.api.v2.resources;
+
+import org.mapstruct.AfterMapping;
+import org.mapstruct.Mapper;
+import org.mapstruct.Mapping;
+import org.mapstruct.MappingTarget;
+import org.slf4j.MDC;
+import sonia.scm.ScmConstraintViolationException;
+import sonia.scm.ScmConstraintViolationException.ScmConstraintViolation;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+@Mapper
+public abstract class ScmViolationExceptionToErrorDtoMapper {
+
+  @Mapping(target = "errorCode", ignore = true)
+  @Mapping(target = "transactionId", ignore = true)
+  @Mapping(target = "context", ignore = true)
+  public abstract ErrorDto map(ScmConstraintViolationException exception);
+
+  @AfterMapping
+  void setTransactionId(@MappingTarget ErrorDto dto) {
+    dto.setTransactionId(MDC.get("transaction_id"));
+  }
+
+  @AfterMapping
+  void mapViolations(ScmConstraintViolationException exception, @MappingTarget ErrorDto dto) {
+    List<ErrorDto.ConstraintViolationDto> violations =
+      exception.getViolations()
+        .stream()
+        .map(this::createViolationDto)
+        .collect(Collectors.toList());
+    dto.setViolations(violations);
+  }
+
+  private ErrorDto.ConstraintViolationDto createViolationDto(ScmConstraintViolation violation) {
+    ErrorDto.ConstraintViolationDto constraintViolationDto = new ErrorDto.ConstraintViolationDto();
+    constraintViolationDto.setMessage(violation.getMessage());
+    constraintViolationDto.setPath(violation.getPropertyPath());
+    return constraintViolationDto;
+  }
+
+  @AfterMapping
+  void setErrorCode(@MappingTarget ErrorDto dto) {
+    dto.setErrorCode("3zR9vPNIE1");
+  }
+
+  @AfterMapping
+  void setMessage(@MappingTarget ErrorDto dto) {
+    dto.setMessage("input violates conditions (see violation list)");
+  }
+}

From 338d0657086d423ba850bf088607aa3fd557d9e9 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20Pfeuffer?= <rene.pfeuffer@cloudogu.com>
Date: Tue, 27 Nov 2018 14:20:28 +0100
Subject: [PATCH 2/5] Fix serialization errors

---
 .../java/sonia/scm/ExceptionWithContext.java  |  2 ++
 .../java/sonia/scm/NotFoundException.java     |  2 ++
 .../scm/ScmConstraintViolationException.java  | 28 +++++++++++--------
 3 files changed, 21 insertions(+), 11 deletions(-)

diff --git a/scm-core/src/main/java/sonia/scm/ExceptionWithContext.java b/scm-core/src/main/java/sonia/scm/ExceptionWithContext.java
index dd87b77210..8702567880 100644
--- a/scm-core/src/main/java/sonia/scm/ExceptionWithContext.java
+++ b/scm-core/src/main/java/sonia/scm/ExceptionWithContext.java
@@ -6,6 +6,8 @@ import static java.util.Collections.unmodifiableList;
 
 public abstract class ExceptionWithContext extends RuntimeException {
 
+  private static final long serialVersionUID = 4327413456580409224L;
+
   private final List<ContextEntry> context;
 
   public ExceptionWithContext(List<ContextEntry> context, String message) {
diff --git a/scm-core/src/main/java/sonia/scm/NotFoundException.java b/scm-core/src/main/java/sonia/scm/NotFoundException.java
index 69b9617e93..9c478da855 100644
--- a/scm-core/src/main/java/sonia/scm/NotFoundException.java
+++ b/scm-core/src/main/java/sonia/scm/NotFoundException.java
@@ -7,6 +7,8 @@ import static java.util.stream.Collectors.joining;
 
 public class NotFoundException extends ExceptionWithContext {
 
+  private static final long serialVersionUID = 1710455380886499111L;
+
   private static final String CODE = "AGR7UzkhA1";
 
   public NotFoundException(Class type, String id) {
diff --git a/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java b/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
index 1fb31dc0fc..d50a1c7591 100644
--- a/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
+++ b/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
@@ -1,19 +1,22 @@
 package sonia.scm;
 
+import java.io.Serializable;
 import java.util.ArrayList;
 import java.util.Collection;
 
 import static java.util.Collections.unmodifiableCollection;
 
-public class ScmConstraintViolationException extends RuntimeException {
+public class ScmConstraintViolationException extends RuntimeException implements Serializable {
+
+  private static final long serialVersionUID = 6904534307450229887L;
 
   private final Collection<ScmConstraintViolation> violations;
 
-  private final String furtherInformations;
+  private final String furtherInformation;
 
-  private ScmConstraintViolationException(Collection<ScmConstraintViolation> violations, String furtherInformations) {
+  private ScmConstraintViolationException(Collection<ScmConstraintViolation> violations, String furtherInformation) {
     this.violations = violations;
-    this.furtherInformations = furtherInformations;
+    this.furtherInformation = furtherInformation;
   }
 
   public Collection<ScmConstraintViolation> getViolations() {
@@ -21,12 +24,12 @@ public class ScmConstraintViolationException extends RuntimeException {
   }
 
   public String getUrl() {
-    return furtherInformations;
+    return furtherInformation;
   }
 
   public static class Builder {
     private final Collection<ScmConstraintViolation> violations = new ArrayList<>();
-    private String furtherInformations;
+    private String furtherInformation;
 
     public static Builder doThrow() {
       Builder builder = new Builder();
@@ -35,7 +38,7 @@ public class ScmConstraintViolationException extends RuntimeException {
 
     public Builder andThrow() {
       this.violations.clear();
-      this.furtherInformations = null;
+      this.furtherInformation = null;
       return this;
     }
 
@@ -44,19 +47,22 @@ public class ScmConstraintViolationException extends RuntimeException {
       return this;
     }
 
-    public Builder withFurtherInformations(String furtherInformations) {
-      this.furtherInformations = furtherInformations;
+    public Builder withFurtherInformation(String furtherInformation) {
+      this.furtherInformation = furtherInformation;
       return this;
     }
 
     public void when(boolean condition) {
       if (condition && !this.violations.isEmpty()) {
-        throw new ScmConstraintViolationException(violations, furtherInformations);
+        throw new ScmConstraintViolationException(violations, furtherInformation);
       }
     }
   }
 
-  public static class ScmConstraintViolation {
+  public static class ScmConstraintViolation implements Serializable {
+
+    private static final long serialVersionUID = -6900317468157084538L;
+
     private final String message;
     private final String path;
 

From 82c8b86386ebf4a7723b2629768ac3d3c7f9f93c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20Pfeuffer?= <rene.pfeuffer@cloudogu.com>
Date: Tue, 27 Nov 2018 14:23:26 +0100
Subject: [PATCH 3/5] Fix sonar issue

---
 .../main/java/sonia/scm/ScmConstraintViolationException.java   | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java b/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
index d50a1c7591..01c628e3dd 100644
--- a/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
+++ b/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
@@ -32,8 +32,7 @@ public class ScmConstraintViolationException extends RuntimeException implements
     private String furtherInformation;
 
     public static Builder doThrow() {
-      Builder builder = new Builder();
-      return builder;
+      return new Builder();
     }
 
     public Builder andThrow() {

From b3dc39772e67f38f097209de7b3066fb2e54f379 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ren=C3=A9=20Pfeuffer?= <rene.pfeuffer@cloudogu.com>
Date: Wed, 28 Nov 2018 10:41:21 +0100
Subject: [PATCH 4/5] Add JavaDoc

---
 .../scm/ScmConstraintViolationException.java  | 57 ++++++++++++++++++-
 1 file changed, 56 insertions(+), 1 deletion(-)

diff --git a/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java b/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
index 01c628e3dd..a28812eb8a 100644
--- a/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
+++ b/scm-core/src/main/java/sonia/scm/ScmConstraintViolationException.java
@@ -6,6 +6,22 @@ import java.util.Collection;
 
 import static java.util.Collections.unmodifiableCollection;
 
+/**
+ * Use this exception to handle invalid input values that cannot be handled using
+ * <a href="https://docs.oracle.com/javaee/7/tutorial/bean-validation001.htm#GIRCZ">JEE bean validation</a>.
+ * Use the {@link Builder} to conditionally create a new exception:
+ * <pre>
+ * Builder
+ *   .doThrow()
+ *   .violation("name or alias must not be empty if not anonymous", "myParameter", "name")
+ *   .violation("name or alias must not be empty if not anonymous", "myParameter", "alias")
+ *   .when(myParameter.getName() == null && myParameter.getAlias() == null && !myParameter.isAnonymous())
+ *   .andThrow()
+ *   .violation("name must be empty if anonymous", "myParameter", "name")
+ *   .when(myParameter.getName() != null && myParameter.isAnonymous());
+ * </pre>
+ * Mind that using this way you do not have to use if-else constructs.
+ */
 public class ScmConstraintViolationException extends RuntimeException implements Serializable {
 
   private static final long serialVersionUID = 6904534307450229887L;
@@ -19,45 +35,84 @@ public class ScmConstraintViolationException extends RuntimeException implements
     this.furtherInformation = furtherInformation;
   }
 
+  /**
+   * The violations that caused this exception.
+   */
   public Collection<ScmConstraintViolation> getViolations() {
     return unmodifiableCollection(violations);
   }
 
+  /**
+   * An optional URL for more informations about this constraint violation.
+   */
   public String getUrl() {
     return furtherInformation;
   }
 
+  /**
+   * Builder to conditionally create constraint violations.
+   */
   public static class Builder {
     private final Collection<ScmConstraintViolation> violations = new ArrayList<>();
     private String furtherInformation;
 
+    /**
+     * Use this to create a new builder instance.
+     */
     public static Builder doThrow() {
       return new Builder();
     }
 
+    /**
+     * Resets this builder to check for further violations.
+     * @return this builder instance.
+     */
     public Builder andThrow() {
       this.violations.clear();
       this.furtherInformation = null;
       return this;
     }
 
+    /**
+     * Describes the violation with a custom message and the affected property. When more than one property is affected,
+     * you can call this method multiple times.
+     * @param message The message describing the violation.
+     * @param pathElements The affected property denoted by the path to reach this property,
+     *                    eg. "someParameter", "complexProperty", "attribute"
+     * @return this builder instance.
+     */
     public Builder violation(String message, String... pathElements) {
       this.violations.add(new ScmConstraintViolation(message, pathElements));
       return this;
     }
 
+    /**
+     * Use this to specify a URL with further information about this violation and hints how to solve this.
+     * This is optional.
+     * @return this builder instance.
+     */
     public Builder withFurtherInformation(String furtherInformation) {
       this.furtherInformation = furtherInformation;
       return this;
     }
 
-    public void when(boolean condition) {
+    /**
+     * When the given condition is <code>true</code>, a exception will be thrown. Otherwise this simply resets this
+     * builder and does nothing else.
+     * @param condition The condition that indicates a violation of this constraint.
+     * @return this builder instance.
+     */
+    public Builder when(boolean condition) {
       if (condition && !this.violations.isEmpty()) {
         throw new ScmConstraintViolationException(violations, furtherInformation);
       }
+      return andThrow();
     }
   }
 
+  /**
+   * A single constraint violation.
+   */
   public static class ScmConstraintViolation implements Serializable {
 
     private static final long serialVersionUID = -6900317468157084538L;

From 58f63e79fa0430cd5fab1be11d7459a46b0e147b Mon Sep 17 00:00:00 2001
From: Sebastian Sdorra <sebastian.sdorra@cloudogu.com>
Date: Fri, 30 Nov 2018 08:37:42 +0000
Subject: [PATCH 5/5] Close branch feature/violations