Initial commit (#310).

src/main/java/org/gitlab4j/api/utils/MaskingLoggingFilter.java

+package org.gitlab4j.api.utils;
+
+import java.io.BufferedInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.FilterOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.net.URI;
+import java.nio.charset.Charset;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map.Entry;
+import java.util.Set;
+import java.util.TreeSet;
+import java.util.concurrent.atomic.AtomicLong;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import javax.annotation.Priority;
+import javax.ws.rs.WebApplicationException;
+import javax.ws.rs.client.ClientRequestContext;
+import javax.ws.rs.client.ClientRequestFilter;
+import javax.ws.rs.client.ClientResponseContext;
+import javax.ws.rs.client.ClientResponseFilter;
+import javax.ws.rs.core.MediaType;
+import javax.ws.rs.core.MultivaluedMap;
+import javax.ws.rs.ext.WriterInterceptor;
+import javax.ws.rs.ext.WriterInterceptorContext;
+
+import org.glassfish.jersey.message.MessageUtils;
+
+
+/**
+ * This class logs request and response info masking HTTP header values that are known to
+ * contain sensitive information.
+ *
+ * This class was patterned after org.glassfish.jersey.logging.LoggingInterceptor, but written in
+ * such a way that it could be sub-classed and have its behavior modified.
+ */
+@Priority(Integer.MIN_VALUE)
+public class MaskingLoggingFilter implements ClientRequestFilter, ClientResponseFilter, WriterInterceptor {
+
+    /**
+     * Default list of header names that should be masked.
+     */
+    public static final List<String> DEFAULT_MASKED_HEADER_NAMES = 
+            Collections.unmodifiableList(Arrays.asList("PRIVATE-TOKEN", "Authorization"));
+
+    /**
+     * Prefix for request log entries.
+     */
+    protected static final String REQUEST_PREFIX = "> ";
+ 
+    /**
+     * Prefix for response log entries.
+     */
+    protected static final String RESPONSE_PREFIX = "< ";
+
+    /**
+     * Prefix that marks the beginning of a request or response section. 
+     */
+    protected static final String SECTION_PREFIX = "- ";
+
+    /**
+     * Property name for the entity stream property
+     */
+    protected static final String ENTITY_STREAM_PROPERTY = MaskingLoggingFilter.class.getName() + ".entityStream";
+
+    /**
+     * Property name for the logging record id property
+     */
+    protected static final String LOGGING_ID_PROPERTY = MaskingLoggingFilter.class.getName() + ".id";
+
+    protected final Logger logger;
+    protected final Level level;
+    protected final int maxEntitySize;
+    protected final AtomicLong _id = new AtomicLong(0);
+    protected Set<String> maskedHeaderNames = new HashSet<String>();
+
+    /**
+     * Creates a masking logging filter for the specified logger with entity logging disabled.
+     *
+     * @param logger the logger to log messages to
+     * @param level level at which the messages will be logged
+     */
+    public MaskingLoggingFilter(final Logger logger, final Level level) {
+        this(logger, level, 0, null);
+    }
+
+    /**
+     * Creates a masking logging filter for the specified logger.
+     *
+     * @param logger the logger to log messages to
+     * @param level level at which the messages will be logged
+     * @param maxEntitySize maximum number of entity bytes to be logged.  When logging if the maxEntitySize
+     * is reached, the entity logging  will be truncated at maxEntitySize and "...more..." will be added at
+     * the end of the log entry. If maxEntitySize is &lt;= 0, entity logging will be disabled
+     */
+    public MaskingLoggingFilter(final Logger logger, final Level level, final int maxEntitySize) {
+        this(logger, level, maxEntitySize, null);
+    }
+
+    /**
+     * Creates a masking logging filter for the specified logger with entity logging disabled.
+     *
+     * @param logger the logger to log messages to
+     * @param level level at which the messages will be logged
+     * @param maskedHeaderNames a list of header names that should have the values masked
+     */
+    public MaskingLoggingFilter(final Logger logger, final Level level, final List<String> maskedHeaderNames) {
+        this(logger, level, 0, maskedHeaderNames);
+    }
+
+    /**
+     * Creates a masking logging filter for the specified logger.
+     *
+     * @param logger the logger to log messages to
+     * @param level level at which the messages will be logged
+     * @param maxEntitySize maximum number of entity bytes to be logged.  When logging if the maxEntitySize
+     * is reached, the entity logging  will be truncated at maxEntitySize and "...more..." will be added at
+     * the end of the log entry. If maxEntitySize is &lt;= 0, entity logging will be disabled
+     * @param maskedHeaderNames a list of header names that should have the values masked
+     */
+    public MaskingLoggingFilter(final Logger logger, final Level level, final int maxEntitySize, final List<String> maskedHeaderNames) {
+        this.logger = logger;
+        this.level = level;
+        this.maxEntitySize = maxEntitySize;
+
+        if (maskedHeaderNames != null) {
+            maskedHeaderNames.forEach(h -> this.maskedHeaderNames.add(h.toLowerCase()));
+        }
+    }
+
+    /**
+     * Set the list of header names to mask values for. If null, will clear the header names to mask.
+     *
+     * @param maskedHeaderNames a list of header names that should have the values masked, if null, will clear
+     * the header names to mask
+     */
+    public void setMaskedHeaderNames(final List<String> maskedHeaderNames) {
+        this.maskedHeaderNames.clear();
+        if (maskedHeaderNames != null) {
+            maskedHeaderNames.forEach(h -> {
+                addMaskedHeaderName(h);
+            });
+        }
+    }
+
+    /**
+     * Add a header name to the list of masked header names.
+     *
+     * @param maskedHeaderName the masked header name to add
+     */
+    public void addMaskedHeaderName(String maskedHeaderName) {
+        if (maskedHeaderName != null) {
+            maskedHeaderName = maskedHeaderName.trim();
+            if (maskedHeaderName.length() > 0) {
+               maskedHeaderNames.add(maskedHeaderName.toLowerCase());
+            }
+        }
+    }
+
+    protected void log(final StringBuilder sb) {
+        if (logger != null) {
+            logger.log(level, sb.toString());
+        }
+    }
+
+    protected StringBuilder appendId(final StringBuilder sb, final long id) {
+        sb.append(Long.toString(id)).append(' ');
+        return (sb);
+    }
+
+    protected void printRequestLine(final StringBuilder sb, final String note, final long id, final String method, final URI uri) {
+        appendId(sb, id).append(SECTION_PREFIX)
+                .append(note)
+                .append(" on thread ").append(Thread.currentThread().getName())
+                .append('\n');
+        appendId(sb, id).append(REQUEST_PREFIX).append(method).append(' ')
+                .append(uri.toASCIIString()).append('\n');
+    }
+
+    protected void printResponseLine(final StringBuilder sb, final String note, final long id, final int status) {
+        appendId(sb, id).append(SECTION_PREFIX)
+                .append(note)
+                .append(" on thread ").append(Thread.currentThread().getName()).append('\n');
+        appendId(sb, id).append(RESPONSE_PREFIX)
+                .append(Integer.toString(status))
+                .append('\n');
+    }
+
+    protected Set<Entry<String, List<String>>> getSortedHeaders(final Set<Entry<String, List<String>>> headers) {
+        final TreeSet<Entry<String, List<String>>> sortedHeaders = new TreeSet<Entry<String, List<String>>>(
+                (Entry<String, List<String>> o1, Entry<String, List<String>> o2) -> o1.getKey().compareToIgnoreCase(o2.getKey()));
+        sortedHeaders.addAll(headers);
+        return sortedHeaders;
+    }
+
+    /**
+     * Logs each of the HTTP headers, masking the value of the header if the header key is
+     * in the list of masked header names.
+     * 
+     * @param sb the StringBuilder to build up the logging info in
+     * @param id the ID for the logging line
+     * @param prefix the logging line prefix character
+     * @param headers a MultiValue map holding the header keys and values
+     */
+    protected void printHeaders(final StringBuilder sb,
+                              final long id,
+                              final String prefix,
+                              final MultivaluedMap<String, String> headers) {
+ 
+        getSortedHeaders(headers.entrySet()).forEach(h -> {
+
+            final List<?> values = h.getValue();
+            final String header = h.getKey();
+            final boolean isMaskedHeader = maskedHeaderNames.contains(header.toLowerCase());
+
+            if (values.size() == 1) {
+                String value = (isMaskedHeader ? "********" : values.get(0).toString());
+                appendId(sb, id).append(prefix).append(header).append(": ").append(value).append('\n');
+            } else {
+                
+                final StringBuilder headerBuf = new StringBuilder();
+                for (final Object value : values) {
+                    if (headerBuf.length() == 0) {
+                        headerBuf.append(", ");
+                    }
+
+                    headerBuf.append(isMaskedHeader ? "********" : value.toString());
+                }
+        
+                appendId(sb, id).append(prefix).append(header).append(": ").append(headerBuf.toString()).append('\n');
+            }
+        });
+    }
+    
+    protected void buildEntityLogString(StringBuilder sb, byte[] entity, int entitySize, Charset charset) {
+
+        sb.append(new String(entity, 0, Math.min(entitySize, maxEntitySize), charset));
+        if (entitySize > maxEntitySize) {
+            sb.append("...more...");
+        }
+
+        sb.append('\n');
+    }
+
+    private InputStream logResponseEntity(final StringBuilder sb, InputStream stream, final Charset charset) throws IOException {
+
+        if (maxEntitySize <= 0) {
+            return (stream);
+        }
+
+        if (!stream.markSupported()) {
+            stream = new BufferedInputStream(stream);
+        }
+
+        stream.mark(maxEntitySize + 1);
+        final byte[] entity = new byte[maxEntitySize + 1];
+        final int entitySize = stream.read(entity);
+        buildEntityLogString(sb, entity, entitySize, charset);
+        stream.reset();
+        return stream;
+    }
+
+    @Override
+    public void filter(ClientRequestContext requestContext) throws IOException {
+
+        if (!logger.isLoggable(level)) {
+            return;
+        }
+
+        final long id = _id.incrementAndGet();
+        requestContext.setProperty(LOGGING_ID_PROPERTY, id);
+
+        final StringBuilder sb = new StringBuilder();
+        printRequestLine(sb, "Sending client request", id, requestContext.getMethod(), requestContext.getUri());
+        printHeaders(sb, id, REQUEST_PREFIX, requestContext.getStringHeaders());
+
+        if (requestContext.hasEntity() && maxEntitySize > 0) {
+            final OutputStream stream = new LoggingStream(sb, requestContext.getEntityStream());
+            requestContext.setEntityStream(stream);
+            requestContext.setProperty(ENTITY_STREAM_PROPERTY, stream);
+        } else {
+            log(sb);
+        }
+    }
+
+    @Override
+    public void filter(ClientRequestContext requestContext, ClientResponseContext responseContext) throws IOException {
+
+        if (!logger.isLoggable(level)) {
+            return;
+        }
+
+        final Object requestId = requestContext.getProperty(LOGGING_ID_PROPERTY);
+        final long id = requestId != null ? (Long) requestId : _id.incrementAndGet();
+
+        final StringBuilder sb = new StringBuilder();
+        printResponseLine(sb, "Received server response", id, responseContext.getStatus());
+        printHeaders(sb, id, RESPONSE_PREFIX, responseContext.getHeaders());
+ 
+        if (responseContext.hasEntity() && maxEntitySize > 0) {
+            responseContext.setEntityStream(logResponseEntity(sb, responseContext.getEntityStream(), 
+                    MessageUtils.getCharset(responseContext.getMediaType())));
+        }
+
+        log(sb);
+    }
+
+    @Override
+    public void aroundWriteTo(WriterInterceptorContext context) throws IOException, WebApplicationException {
+
+        final LoggingStream stream = (LoggingStream) context.getProperty(ENTITY_STREAM_PROPERTY);
+        context.proceed();
+        if (stream == null) {
+            return;
+        }
+        
+        MediaType mediaType = context.getMediaType();
+        if (mediaType.isCompatible(MediaType.APPLICATION_JSON_TYPE) ||
+                mediaType.isCompatible(MediaType.APPLICATION_FORM_URLENCODED_TYPE)) {
+            log(stream.getStringBuilder(MessageUtils.getCharset(mediaType)));
+        }
+
+    }
+
+    /**
+     * This class is responsible for logging the request entities, it will truncate at maxEntitySize
+     * and add "...more..." to the end of the entity log string.
+     */
+    protected class LoggingStream extends FilterOutputStream {
+
+        private final StringBuilder sb;
+        private final ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+
+        LoggingStream(StringBuilder sb, OutputStream out) {
+            super(out);
+            this.sb = sb;
+        }
+
+        StringBuilder getStringBuilder(Charset charset) {
+            final byte[] entity = outputStream.toByteArray();
+            buildEntityLogString(sb, entity, entity.length, charset);
+            return (sb);
+        }
+
+        @Override
+        public void write(final int i) throws IOException {
+
+            if (outputStream.size() <= maxEntitySize) {
+                outputStream.write(i);
+            }
+
+            out.write(i);
+        }
+    }
+}