001package de.deepamehta.accesscontrol;
002
003import javax.servlet.http.HttpServletRequest;
004
005import java.util.ArrayList;
006import java.util.List;
007
008
009
010class GlobalRequestFilter {
011
012    // ---------------------------------------------------------------------------------------------- Instance Variables
013
014    private List<String> prefixesRead;
015    private List<String> prefixesWrite;
016
017    // ---------------------------------------------------------------------------------------------------- Constructors
018
019    GlobalRequestFilter(String settingRead, String settingWrite) {
020        this.prefixesRead  = initPrefixes(settingRead);
021        this.prefixesWrite = initPrefixes(settingWrite);
022    }
023
024    // ----------------------------------------------------------------------------------------- Package Private Methods
025
026    boolean isAnonymousRequestAllowed(HttpServletRequest request) {
027        return request.getMethod().equals("GET") ?
028            prefixMatch(request, prefixesRead) :
029            prefixMatch(request, prefixesWrite);
030    }
031
032    // ---
033
034    String dumpReadSetting() {
035        return dumpSetting(prefixesRead);
036    }
037
038    String dumpWriteSetting() {
039        return dumpSetting(prefixesWrite);
040    }
041
042    // ------------------------------------------------------------------------------------------------- Private Methods
043
044    private List<String> initPrefixes(String setting) {
045        if (setting.equals("ALL")) {
046            return null;
047        } else if (setting.equals("NONE")) {
048            return new ArrayList();
049        } else {
050            String[] p = setting.split(",\\s*");    // ignore whitespace after comma
051            List<String> prefixes = new ArrayList();
052            for (int i = 0; i < p.length; i++) {
053                prefixes.add(p[i] + "/");
054            }
055            return prefixes;
056        }
057    }
058
059    private boolean prefixMatch(HttpServletRequest request, List<String> prefixes) {
060        if (prefixes == null) {
061            return true;
062        }
063        for (String prefix : prefixes) {
064            if (request.getRequestURI().startsWith(prefix)) {
065                return true;
066            }
067        }
068        return false;
069    }
070
071    private String dumpSetting(List<String> prefixes) {
072        if (prefixes == null) {
073            return "ALL";
074        } else if (prefixes.isEmpty()) {
075            return "NONE";
076        } else {
077            return prefixes.toString();
078        }
079    }
080}