com.helger.photon.api.InvokableAPIDescriptor Maven / Gradle / Ivy
/**
* Copyright (C) 2014-2020 Philip Helger (www.helger.com)
* philip[at]helger[dot]com
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.helger.photon.api;
import java.io.Serializable;
import javax.annotation.Nonnull;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.helger.commons.CGlobal;
import com.helger.commons.ValueEnforcer;
import com.helger.commons.annotation.Nonempty;
import com.helger.commons.annotation.ReturnsMutableCopy;
import com.helger.commons.collection.impl.ICommonsOrderedMap;
import com.helger.commons.http.CHttp;
import com.helger.commons.mime.MimeType;
import com.helger.commons.mime.MimeTypeParser;
import com.helger.commons.mutable.MutableInt;
import com.helger.commons.string.ToStringGenerator;
import com.helger.servlet.response.UnifiedResponse;
import com.helger.web.scope.IRequestWebScopeWithoutResponse;
/**
* An {@link InvokableAPIDescriptor} contains an {@link IAPIDescriptor} as well
* the original path by which it was called as well as any resolved path
* variables.
*
* @author Philip Helger
*/
public final class InvokableAPIDescriptor implements Serializable
{
private static final Logger LOGGER = LoggerFactory.getLogger (InvokableAPIDescriptor.class);
private final IAPIDescriptor m_aDescriptor;
private final String m_sPath;
private final ICommonsOrderedMap m_aPathVariables;
/**
* Constructor
*
* @param aDescriptor
* The matching {@link IAPIDescriptor}. Never null.
* @param sPath
* The URL path requested by the user, relative to the servlet.
* @param aPathVariables
* All resolved path variables, if the path descriptor contains
* variable elements.
*/
public InvokableAPIDescriptor (@Nonnull final IAPIDescriptor aDescriptor,
@Nonnull @Nonempty final String sPath,
@Nonnull final ICommonsOrderedMap aPathVariables)
{
ValueEnforcer.notNull (aDescriptor, "Descriptor");
ValueEnforcer.notEmpty (sPath, "Path");
ValueEnforcer.notNull (aPathVariables, "PathVariables");
m_aDescriptor = aDescriptor;
m_sPath = sPath;
m_aPathVariables = aPathVariables.getClone ();
}
/**
* @return The original API descriptor. Never null.
*/
@Nonnull
public final IAPIDescriptor getAPIDescriptor ()
{
return m_aDescriptor;
}
/**
* @return The URL path requested by the user, relative to the servlet. Never
* null nor empty.
*/
@Nonnull
@Nonempty
public final String getPath ()
{
return m_sPath;
}
/**
* @return All resolved path variables, if the path descriptor contains
* variable elements. Never null but maybe empty.
*/
@Nonnull
@ReturnsMutableCopy
public final ICommonsOrderedMap getAllPathVariables ()
{
return m_aPathVariables.getClone ();
}
/**
* Check if all pre-requisites are handled correctly. This checks if all
* required headers and params are present.
*
* @param aRequestScope
* The request scope to validate.
* @param aStatusCode
* The mutable int to hold the status code to be returned in case of
* error. Default is HTTP 400, bad request.
* @return true if all prerequisites are fulfilled.
*/
public boolean canExecute (@Nonnull final IRequestWebScopeWithoutResponse aRequestScope,
@Nonnull final MutableInt aStatusCode)
{
if (aRequestScope == null)
return false;
// Note: HTTP method was already checked in APIDescriptorList
// Check required headers
for (final String sRequiredHeader : m_aDescriptor.requiredHeaders ())
if (aRequestScope.headers ().getFirstHeaderValue (sRequiredHeader) == null)
{
LOGGER.warn ("Request '" + m_sPath + "' is missing required HTTP header '" + sRequiredHeader + "'");
return false;
}
// Check required parameters
for (final String sRequiredParam : m_aDescriptor.requiredParams ())
if (!aRequestScope.params ().containsKey (sRequiredParam))
{
LOGGER.warn ("Request '" + m_sPath + "' is missing required HTTP parameter '" + sRequiredParam + "'");
return false;
}
// Check explicit filter
if (m_aDescriptor.hasExecutionFilter ())
if (!m_aDescriptor.getExecutionFilter ().canExecute (aRequestScope))
{
LOGGER.warn ("Request '" + m_sPath + "' cannot be executed because of ExecutionFilter");
return false;
}
if (m_aDescriptor.allowedMimeTypes ().isNotEmpty ())
{
final String sContentType = aRequestScope.getContentType ();
// Parse to extract any parameters etc.
final MimeType aMT = MimeTypeParser.safeParseMimeType (sContentType);
// If parsing fails, use the provided String
final String sMimeTypeToCheck = aMT == null ? sContentType : aMT.getAsStringWithoutParameters ();
if (!m_aDescriptor.allowedMimeTypes ().contains (sMimeTypeToCheck) &&
!m_aDescriptor.allowedMimeTypes ().contains (sMimeTypeToCheck.toLowerCase (CGlobal.DEFAULT_LOCALE)))
{
LOGGER.warn ("Request '" +
m_sPath +
"' contains the Content-Type '" +
sContentType +
"' which is not in the allowed list of " +
m_aDescriptor.allowedMimeTypes ());
// Special error code HTTP 415
aStatusCode.set (CHttp.HTTP_UNSUPPORTED_MEDIA_TYPE);
return false;
}
}
return true;
}
/**
* Invoke the Java callback underlying this API descriptor. Note: this method
* may only be invoked after
* {@link #canExecute(IRequestWebScopeWithoutResponse,MutableInt)} returned
* true!
*
* @param aRequestScope
* Current request scope. Never null.
* @param aUnifiedResponse
* Current response. Never null.
* @throws Exception
* In case the Java callback throws one
* @throws IllegalStateException
* In case the executor factory creates a null executor.
*/
public void invokeAPI (@Nonnull final IRequestWebScopeWithoutResponse aRequestScope,
@Nonnull final UnifiedResponse aUnifiedResponse) throws Exception
{
final IAPIExecutor aExecutor = m_aDescriptor.getExecutorFactory ().get ();
if (aExecutor == null)
throw new IllegalStateException ("Failed to created API executor for: " + toString ());
// Go go go
aExecutor.invokeAPI (m_aDescriptor, m_sPath, m_aPathVariables, aRequestScope, aUnifiedResponse);
}
@Override
public String toString ()
{
return new ToStringGenerator (this).append ("APIDescriptor", m_aDescriptor)
.append ("Path", m_sPath)
.append ("PathVariables", m_aPathVariables)
.getToString ();
}
}