001package org.hl7.fhir.r4.terminologies;
002
003/*
004  Copyright (c) 2011+, HL7, Inc.
005  All rights reserved.
006  
007  Redistribution and use in source and binary forms, with or without modification, 
008  are permitted provided that the following conditions are met:
009    
010   * Redistributions of source code must retain the above copyright notice, this 
011     list of conditions and the following disclaimer.
012   * Redistributions in binary form must reproduce the above copyright notice, 
013     this list of conditions and the following disclaimer in the documentation 
014     and/or other materials provided with the distribution.
015   * Neither the name of HL7 nor the names of its contributors may be used to 
016     endorse or promote products derived from this software without specific 
017     prior written permission.
018  
019  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND 
020  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 
021  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 
022  IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 
023  INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 
024  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
025  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
026  WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
027  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
028  POSSIBILITY OF SUCH DAMAGE.
029  
030 */
031
032/*
033Copyright (c) 2011+, HL7, Inc
034All rights reserved.
035
036Redistribution and use in source and binary forms, with or without modification, 
037are permitted provided that the following conditions are met:
038
039 * Redistributions of source code must retain the above copyright notice, this 
040   list of conditions and the following disclaimer.
041 * Redistributions in binary form must reproduce the above copyright notice, 
042   this list of conditions and the following disclaimer in the documentation 
043   and/or other materials provided with the distribution.
044 * Neither the name of HL7 nor the names of its contributors may be used to 
045   endorse or promote products derived from this software without specific 
046   prior written permission.
047
048THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND 
049ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 
050WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 
051IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, 
052INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 
053NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
054PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
055WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
056ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
057POSSIBILITY OF SUCH DAMAGE.
058
059*/
060
061import java.io.File;
062import java.io.FileInputStream;
063import java.io.FileOutputStream;
064import java.io.IOException;
065import java.util.HashMap;
066import java.util.Map;
067
068import org.apache.commons.io.IOUtils;
069import org.hl7.fhir.exceptions.FHIRFormatError;
070import org.hl7.fhir.r4.context.IWorkerContext;
071import org.hl7.fhir.r4.formats.IParser.OutputStyle;
072import org.hl7.fhir.r4.formats.JsonParser;
073import org.hl7.fhir.r4.model.MetadataResource;
074import org.hl7.fhir.r4.model.OperationOutcome;
075import org.hl7.fhir.r4.model.Parameters;
076import org.hl7.fhir.r4.model.Resource;
077import org.hl7.fhir.r4.model.ValueSet;
078import org.hl7.fhir.r4.terminologies.ValueSetExpander.TerminologyServiceErrorClass;
079import org.hl7.fhir.r4.terminologies.ValueSetExpander.ValueSetExpansionOutcome;
080import org.hl7.fhir.r4.utils.ToolingExtensions;
081import org.hl7.fhir.utilities.Utilities;
082import org.hl7.fhir.utilities.filesystem.ManagedFileAccess;
083import org.hl7.fhir.utilities.xhtml.XhtmlComposer;
084
085public class ValueSetExpansionCache implements ValueSetExpanderFactory {
086
087  public class CacheAwareExpander implements ValueSetExpander {
088
089    @Override
090    public ValueSetExpansionOutcome expand(ValueSet source, Parameters expParams) throws ETooCostly, IOException {
091      String cacheKey = makeCacheKey(source, expParams);
092      if (expansions.containsKey(cacheKey))
093        return expansions.get(cacheKey);
094      ValueSetExpander vse = new ValueSetExpanderSimple(context);
095      ValueSetExpansionOutcome vso = vse.expand(source, expParams);
096      if (vso.getError() != null) {
097        // well, we'll see if the designated server can expand it, and if it can, we'll
098        // cache it locally
099        vso = context.expandVS(source, false, expParams == null || !expParams.getParameterBool("excludeNested"));
100        if (cacheFolder != null) {
101          FileOutputStream s = ManagedFileAccess.outStream(Utilities.path(cacheFolder, makeFileName(source.getUrl())));
102          context.newXmlParser().setOutputStyle(OutputStyle.PRETTY).compose(s, vso.getValueset());
103          s.close();
104        }
105      }
106      if (vso.getValueset() != null)
107        expansions.put(cacheKey, vso);
108      return vso;
109    }
110
111    private String makeCacheKey(ValueSet source, Parameters expParams) throws IOException {
112      if (expParams == null)
113        return source.getUrl();
114      JsonParser p = new JsonParser();
115      String r = p.composeString(expParams);
116      return source.getUrl() + " " + r.hashCode();
117    }
118
119  }
120
121  private static final String VS_ID_EXT = "http://tools/cache";
122
123  private final Map<String, ValueSetExpansionOutcome> expansions = new HashMap<String, ValueSetExpansionOutcome>();
124  private final Map<String, MetadataResource> canonicals = new HashMap<String, MetadataResource>();
125  private final IWorkerContext context;
126  private final String cacheFolder;
127
128  private Object lock;
129
130  public ValueSetExpansionCache(IWorkerContext context, Object lock) {
131    super();
132    cacheFolder = null;
133    this.lock = lock;
134    this.context = context;
135  }
136
137  public ValueSetExpansionCache(IWorkerContext context, String cacheFolder, Object lock)
138      throws FHIRFormatError, IOException {
139    super();
140    this.context = context;
141    this.cacheFolder = cacheFolder;
142    this.lock = lock;
143    if (this.cacheFolder != null)
144      loadCache();
145  }
146
147  private String makeFileName(String url) {
148    return url.replace("$", "").replace(":", "").replace("|", ".").replace("//", "/").replace("/", "_") + ".xml";
149  }
150
151  private void loadCache() throws FHIRFormatError, IOException {
152    File[] files = ManagedFileAccess.file(cacheFolder).listFiles();
153    for (File f : files) {
154      if (f.getName().endsWith(".xml")) {
155        final FileInputStream is = ManagedFileAccess.inStream(f);
156        try {
157          Resource r = context.newXmlParser().setOutputStyle(OutputStyle.PRETTY).parse(is);
158          if (r instanceof OperationOutcome) {
159            OperationOutcome oo = (OperationOutcome) r;
160            expansions.put(ToolingExtensions.getExtension(oo, VS_ID_EXT).getValue().toString(),
161                new ValueSetExpansionOutcome(
162                    new XhtmlComposer(XhtmlComposer.XML, false).composePlainText(oo.getText().getDiv()),
163                    TerminologyServiceErrorClass.UNKNOWN));
164          } else if (r instanceof ValueSet) {
165            ValueSet vs = (ValueSet) r;
166            if (vs.hasExpansion())
167              expansions.put(vs.getUrl(), new ValueSetExpansionOutcome(vs));
168            else {
169              canonicals.put(vs.getUrl(), vs);
170              if (vs.hasVersion())
171                canonicals.put(vs.getUrl() + "|" + vs.getVersion(), vs);
172            }
173          } else if (r instanceof MetadataResource) {
174            MetadataResource md = (MetadataResource) r;
175            canonicals.put(md.getUrl(), md);
176            if (md.hasVersion())
177              canonicals.put(md.getUrl() + "|" + md.getVersion(), md);
178          }
179        } finally {
180          IOUtils.closeQuietly(is);
181        }
182      }
183    }
184  }
185
186  @Override
187  public ValueSetExpander getExpander() {
188    return new CacheAwareExpander();
189    // return new ValueSetExpander(valuesets, codesystems);
190  }
191
192  public MetadataResource getStoredResource(String canonicalUri) {
193    synchronized (lock) {
194      return canonicals.get(canonicalUri);
195    }
196  }
197
198  public void storeResource(MetadataResource md) throws IOException {
199    synchronized (lock) {
200      canonicals.put(md.getUrl(), md);
201      if (md.hasVersion())
202        canonicals.put(md.getUrl() + "|" + md.getVersion(), md);
203    }
204    if (cacheFolder != null) {
205      FileOutputStream s = ManagedFileAccess.outStream(
206          Utilities.path(cacheFolder, makeFileName(md.getUrl() + "|" + md.getVersion())));
207      context.newXmlParser().setOutputStyle(OutputStyle.PRETTY).compose(s, md);
208      s.close();
209    }
210  }
211
212}