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.xhtml.XhtmlComposer;
083
084public class ValueSetExpansionCache implements ValueSetExpanderFactory {
085
086  public class CacheAwareExpander implements ValueSetExpander {
087
088    @Override
089    public ValueSetExpansionOutcome expand(ValueSet source, Parameters expParams) throws ETooCostly, IOException {
090      String cacheKey = makeCacheKey(source, expParams);
091      if (expansions.containsKey(cacheKey))
092        return expansions.get(cacheKey);
093      ValueSetExpander vse = new ValueSetExpanderSimple(context);
094      ValueSetExpansionOutcome vso = vse.expand(source, expParams);
095      if (vso.getError() != null) {
096        // well, we'll see if the designated server can expand it, and if it can, we'll
097        // cache it locally
098        vso = context.expandVS(source, false, expParams == null || !expParams.getParameterBool("excludeNested"));
099        if (cacheFolder != null) {
100          FileOutputStream s = new FileOutputStream(Utilities.path(cacheFolder, makeFileName(source.getUrl())));
101          context.newXmlParser().setOutputStyle(OutputStyle.PRETTY).compose(s, vso.getValueset());
102          s.close();
103        }
104      }
105      if (vso.getValueset() != null)
106        expansions.put(cacheKey, vso);
107      return vso;
108    }
109
110    private String makeCacheKey(ValueSet source, Parameters expParams) throws IOException {
111      if (expParams == null)
112        return source.getUrl();
113      JsonParser p = new JsonParser();
114      String r = p.composeString(expParams);
115      return source.getUrl() + " " + r.hashCode();
116    }
117
118  }
119
120  private static final String VS_ID_EXT = "http://tools/cache";
121
122  private final Map<String, ValueSetExpansionOutcome> expansions = new HashMap<String, ValueSetExpansionOutcome>();
123  private final Map<String, MetadataResource> canonicals = new HashMap<String, MetadataResource>();
124  private final IWorkerContext context;
125  private final String cacheFolder;
126
127  private Object lock;
128
129  public ValueSetExpansionCache(IWorkerContext context, Object lock) {
130    super();
131    cacheFolder = null;
132    this.lock = lock;
133    this.context = context;
134  }
135
136  public ValueSetExpansionCache(IWorkerContext context, String cacheFolder, Object lock)
137      throws FHIRFormatError, IOException {
138    super();
139    this.context = context;
140    this.cacheFolder = cacheFolder;
141    this.lock = lock;
142    if (this.cacheFolder != null)
143      loadCache();
144  }
145
146  private String makeFileName(String url) {
147    return url.replace("$", "").replace(":", "").replace("|", ".").replace("//", "/").replace("/", "_") + ".xml";
148  }
149
150  private void loadCache() throws FHIRFormatError, IOException {
151    File[] files = new File(cacheFolder).listFiles();
152    for (File f : files) {
153      if (f.getName().endsWith(".xml")) {
154        final FileInputStream is = new FileInputStream(f);
155        try {
156          Resource r = context.newXmlParser().setOutputStyle(OutputStyle.PRETTY).parse(is);
157          if (r instanceof OperationOutcome) {
158            OperationOutcome oo = (OperationOutcome) r;
159            expansions.put(ToolingExtensions.getExtension(oo, VS_ID_EXT).getValue().toString(),
160                new ValueSetExpansionOutcome(
161                    new XhtmlComposer(XhtmlComposer.XML, false).composePlainText(oo.getText().getDiv()),
162                    TerminologyServiceErrorClass.UNKNOWN));
163          } else if (r instanceof ValueSet) {
164            ValueSet vs = (ValueSet) r;
165            if (vs.hasExpansion())
166              expansions.put(vs.getUrl(), new ValueSetExpansionOutcome(vs));
167            else {
168              canonicals.put(vs.getUrl(), vs);
169              if (vs.hasVersion())
170                canonicals.put(vs.getUrl() + "|" + vs.getVersion(), vs);
171            }
172          } else if (r instanceof MetadataResource) {
173            MetadataResource md = (MetadataResource) r;
174            canonicals.put(md.getUrl(), md);
175            if (md.hasVersion())
176              canonicals.put(md.getUrl() + "|" + md.getVersion(), md);
177          }
178        } finally {
179          IOUtils.closeQuietly(is);
180        }
181      }
182    }
183  }
184
185  @Override
186  public ValueSetExpander getExpander() {
187    return new CacheAwareExpander();
188    // return new ValueSetExpander(valuesets, codesystems);
189  }
190
191  public MetadataResource getStoredResource(String canonicalUri) {
192    synchronized (lock) {
193      return canonicals.get(canonicalUri);
194    }
195  }
196
197  public void storeResource(MetadataResource md) throws IOException {
198    synchronized (lock) {
199      canonicals.put(md.getUrl(), md);
200      if (md.hasVersion())
201        canonicals.put(md.getUrl() + "|" + md.getVersion(), md);
202    }
203    if (cacheFolder != null) {
204      FileOutputStream s = new FileOutputStream(
205          Utilities.path(cacheFolder, makeFileName(md.getUrl() + "|" + md.getVersion())));
206      context.newXmlParser().setOutputStyle(OutputStyle.PRETTY).compose(s, md);
207      s.close();
208    }
209  }
210
211}