writerpoolprocessor.html

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<a name="139" href="#139">139</a> <em>     * CrawlURI annotation indicating no record was written</em>
<a name="140" href="#140">140</a> <em>     */</em>
<a name="141" href="#141">141</a>     <strong>protected</strong> <strong>static</strong> <strong>final</strong> String ANNOTATION_UNWRITTEN = <span class="string">"unwritten"</span>;
<a name="142" href="#142">142</a>     
<a name="143" href="#143">143</a>     <em>/**<em>*</em></em>
<a name="144" href="#144">144</a> <em>     * Default maximum file size.</em>
<a name="145" href="#145">145</a> <em>     * TODO: Check that subclasses can set a different MAX_FILE_SIZE and</em>
<a name="146" href="#146">146</a> <em>     * it will be used in the constructor as default.</em>
<a name="147" href="#147">147</a> <em>     */</em>
<a name="148" href="#148">148</a>     <strong>private</strong> <strong>static</strong> <strong>final</strong> <strong>int</strong> DEFAULT_MAX_FILE_SIZE = 100000000;
<a name="149" href="#149">149</a>     
<a name="150" href="#150">150</a>     <em>/**<em>*</em></em>
<a name="151" href="#151">151</a> <em>     * Default path list.</em>
<a name="152" href="#152">152</a> <em>     * </em>
<a name="153" href="#153">153</a> <em>     * TODO: Confirm this one gets picked up.</em>
<a name="154" href="#154">154</a> <em>     */</em>
<a name="155" href="#155">155</a>     <strong>private</strong> <strong>static</strong> <strong>final</strong> String [] DEFAULT_PATH = {<span class="string">"crawl-store"</span>};
<a name="156" href="#156">156</a> 
<a name="157" href="#157">157</a>     <em>/**<em>*</em></em>
<a name="158" href="#158">158</a> <em>     * Reference to pool.</em>
<a name="159" href="#159">159</a> <em>     */</em>
<a name="160" href="#160">160</a>     <strong>transient</strong> <strong>private</strong> <a href="../../../../org/archive/io/WriterPool.html">WriterPool</a> pool = <strong>null</strong>;
<a name="161" href="#161">161</a>     
<a name="162" href="#162">162</a>     <em>/**<em>*</em></em>
<a name="163" href="#163">163</a> <em>     * Total number of bytes written to disc.</em>
<a name="164" href="#164">164</a> <em>     */</em>
<a name="165" href="#165">165</a>     <strong>private</strong> <strong>long</strong> totalBytesWritten = 0;
<a name="166" href="#166">166</a>     
<a name="167" href="#167">167</a>     <em>/**<em>*</em></em>
<a name="168" href="#168">168</a> <em>     * Calculate metadata once only.</em>
<a name="169" href="#169">169</a> <em>     */</em>
<a name="170" href="#170">170</a>     <strong>transient</strong> <strong>private</strong> List&lt;String> cachedMetadata = <strong>null</strong>;
<a name="171" href="#171">171</a> 
<a name="172" href="#172">172</a> 
<a name="173" href="#173">173</a>     <em>/**<em>*</em></em>
<a name="174" href="#174">174</a> <em>     * @param name Name of this processor.</em>
<a name="175" href="#175">175</a> <em>     */</em>
<a name="176" href="#176">176</a>     <strong>public</strong> <a href="../../../../org/archive/crawler/framework/WriterPoolProcessor.html">WriterPoolProcessor</a>(String name) {
<a name="177" href="#177">177</a>     	<strong>this</strong>(name, <span class="string">"Pool of files processor"</span>);
<a name="178" href="#178">178</a>     }
<a name="179" href="#179">179</a>     	
<a name="180" href="#180">180</a>     <em>/**<em>*</em></em>
<a name="181" href="#181">181</a> <em>     * @param name Name of this processor.</em>
<a name="182" href="#182">182</a> <em>     * @param description Description for this processor.</em>
<a name="183" href="#183">183</a> <em>     */</em>
<a name="184" href="#184">184</a>     <strong>public</strong> <a href="../../../../org/archive/crawler/framework/WriterPoolProcessor.html">WriterPoolProcessor</a>(<strong>final</strong> String name,
<a name="185" href="#185">185</a>         		<strong>final</strong> String description) {
<a name="186" href="#186">186</a>         <strong>super</strong>(name, description);
<a name="187" href="#187">187</a>         <a href="../../../../org/archive/crawler/settings/Type.html">Type</a> e = addElementToDefinition(
<a name="188" href="#188">188</a>             <strong>new</strong> <a href="../../../../org/archive/crawler/settings/SimpleType.html">SimpleType</a>(ATTR_COMPRESS, <span class="string">"Compress files when "</span> +
<a name="189" href="#189">189</a>             	<span class="string">"writing to disk."</span>, <strong>new</strong> Boolean(DEFAULT_COMPRESS)));
<a name="190" href="#190">190</a>         e.setOverrideable(false);
<a name="191" href="#191">191</a>         e = addElementToDefinition(
<a name="192" href="#192">192</a>             <strong>new</strong> <a href="../../../../org/archive/crawler/settings/SimpleType.html">SimpleType</a>(ATTR_PREFIX, 
<a name="193" href="#193">193</a>                 <span class="string">"File prefix. "</span> +
<a name="194" href="#194">194</a>                 <span class="string">"The text supplied here will be used as a prefix naming "</span> +
<a name="195" href="#195">195</a>                 <span class="string">"writer files.  For example if the prefix is 'IAH', "</span> +
<a name="196" href="#196">196</a>                 <span class="string">"then file names will look like "</span> +
<a name="197" href="#197">197</a>                 <span class="string">"IAH-20040808101010-0001-HOSTNAME.arc.gz "</span> +
<a name="198" href="#198">198</a>                 <span class="string">"...if writing ARCs (The prefix will be "</span> +
<a name="199" href="#199">199</a>                 <span class="string">"separated from the date by a hyphen)."</span>,
<a name="200" href="#200">200</a>                 WriterPoolMember.DEFAULT_PREFIX));
<a name="201" href="#201">201</a>         e = addElementToDefinition(
<a name="202" href="#202">202</a>             <strong>new</strong> <a href="../../../../org/archive/crawler/settings/SimpleType.html">SimpleType</a>(ATTR_SUFFIX, <span class="string">"Suffix to tag onto "</span> +
<a name="203" href="#203">203</a>                 <span class="string">"files. If value is '${HOSTNAME}', will use hostname for "</span> +
<a name="204" href="#204">204</a>                 <span class="string">"suffix. If empty, no suffix will be added."</span>,
<a name="205" href="#205">205</a>                 WriterPoolMember.DEFAULT_SUFFIX));
<a name="206" href="#206">206</a>         e.setOverrideable(false);
<a name="207" href="#207">207</a>         e = addElementToDefinition(
<a name="208" href="#208">208</a>             <strong>new</strong> <a href="../../../../org/archive/crawler/settings/SimpleType.html">SimpleType</a>(ATTR_MAX_SIZE_BYTES, <span class="string">"Max size of each file"</span>,
<a name="209" href="#209">209</a>                 <strong>new</strong> Long(DEFAULT_MAX_FILE_SIZE)));
<a name="210" href="#210">210</a>         e.setOverrideable(false);
<a name="211" href="#211">211</a>         e = addElementToDefinition(
<a name="212" href="#212">212</a>             <strong>new</strong> <a href="../../../../org/archive/crawler/settings/StringList.html">StringList</a>(ATTR_PATH, <span class="string">"Where to files. "</span> +
<a name="213" href="#213">213</a>                 <span class="string">"Supply absolute or relative path.  If relative, files "</span> +
<a name="214" href="#214">214</a>                 <span class="string">"will be written relative to "</span> +
<a name="215" href="#215">215</a>                 <span class="string">"the "</span> + CrawlOrder.ATTR_DISK_PATH + <span class="string">"setting."</span> +
<a name="216" href="#216">216</a>                 <span class="string">" If more than one path specified, we'll round-robin"</span> +
<a name="217" href="#217">217</a>                 <span class="string">" dropping files to each.  This setting is safe"</span> +
<a name="218" href="#218">218</a>                 <span class="string">" to change midcrawl (You can remove and add new dirs"</span> +
<a name="219" href="#219">219</a>                 <span class="string">" as the crawler progresses)."</span>, getDefaultPath()));
<a name="220" href="#220">220</a>         e.setOverrideable(false);
<a name="221" href="#221">221</a>         e = addElementToDefinition(<strong>new</strong> <a href="../../../../org/archive/crawler/settings/SimpleType.html">SimpleType</a>(ATTR_POOL_MAX_ACTIVE,
<a name="222" href="#222">222</a>             <span class="string">"Maximum active files in pool. "</span> +
<a name="223" href="#223">223</a>             <span class="string">"This setting cannot be varied over the life of a crawl."</span>,
<a name="224" href="#224">224</a>             <strong>new</strong> Integer(WriterPool.DEFAULT_MAX_ACTIVE)));
<a name="225" href="#225">225</a>         e.setOverrideable(false);
<a name="226" href="#226">226</a>         e = addElementToDefinition(<strong>new</strong> <a href="../../../../org/archive/crawler/settings/SimpleType.html">SimpleType</a>(ATTR_POOL_MAX_WAIT,
<a name="227" href="#227">227</a>             <span class="string">"Maximum time to wait on pool element"</span> +
<a name="228" href="#228">228</a>             <span class="string">" (milliseconds). This setting cannot be varied over the life"</span> +
<a name="229" href="#229">229</a>             <span class="string">" of a crawl."</span>,
<a name="230" href="#230">230</a>             <strong>new</strong> Integer(WriterPool.DEFAULT_MAXIMUM_WAIT)));
<a name="231" href="#231">231</a>         e.setOverrideable(false);
<a name="232" href="#232">232</a>         e = addElementToDefinition(<strong>new</strong> <a href="../../../../org/archive/crawler/settings/SimpleType.html">SimpleType</a>(ATTR_MAX_BYTES_WRITTEN,
<a name="233" href="#233">233</a>             <span class="string">"Total file bytes to write to disk."</span> +
<a name="234" href="#234">234</a>             <span class="string">" Once the size of all files on disk has exceeded this "</span> +
<a name="235" href="#235">235</a>             <span class="string">"limit, this processor will stop the crawler. "</span> +
<a name="236" href="#236">236</a>             <span class="string">"A value of zero means no upper limit."</span>, <strong>new</strong> Long(0)));
<a name="237" href="#237">237</a>         e.setOverrideable(false);
<a name="238" href="#238">238</a>         e.setExpertSetting(<strong>true</strong>);
<a name="239" href="#239">239</a>         e = addElementToDefinition(<strong>new</strong> <a href="../../../../org/archive/crawler/settings/SimpleType.html">SimpleType</a>(ATTR_SKIP_IDENTICAL_DIGESTS,
<a name="240" href="#240">240</a>                 <span class="string">"Whether to skip the writing of a record when URI "</span> +
<a name="241" href="#241">241</a>                 <span class="string">"history information is available and indicates the "</span> +
<a name="242" href="#242">242</a>                 <span class="string">"prior fetch had an identical content digest. "</span> +
<a name="243" href="#243">243</a>                 <span class="string">"Default is false."</span>, <strong>new</strong> Boolean(false)));
<a name="244" href="#244">244</a>         e.setOverrideable(<strong>true</strong>);
<a name="245" href="#245">245</a>         e.setExpertSetting(<strong>true</strong>);
<a name="246" href="#246">246</a>     }
<a name="247" href="#247">247</a>     
<a name="248" href="#248">248</a>     <strong>protected</strong> String [] getDefaultPath() {
<a name="249" href="#249">249</a>     	<strong>return</strong> DEFAULT_PATH;
<a name="250" href="#250">250</a> 	}
<a name="251" href="#251">251</a> 
<a name="252" href="#252">252</a>     <strong>public</strong> <strong>synchronized</strong> <strong>void</strong> initialTasks() {
<a name="253" href="#253">253</a>         <em class="comment">// Add this class to crawl state listeners and setup pool.</em>
<a name="254" href="#254">254</a>         getSettingsHandler().getOrder().getController().
<a name="255" href="#255">255</a>             addCrawlStatusListener(<strong>this</strong>);
<a name="256" href="#256">256</a>         setupPool(<strong>new</strong> AtomicInteger());
<a name="257" href="#257">257</a>         <em class="comment">// Run checkpoint recovery code.</em>
<a name="258" href="#258">258</a>         <strong>if</strong> (getSettingsHandler().getOrder().getController().
<a name="259" href="#259">259</a>         		isCheckpointRecover()) {
<a name="260" href="#260">260</a>         	checkpointRecover();
<a name="261" href="#261">261</a>         }
<a name="262" href="#262">262</a>     }
<a name="263" href="#263">263</a>     
<a name="264" href="#264">264</a>     <strong>protected</strong> AtomicInteger getSerialNo() {
<a name="265" href="#265">265</a>         <strong>return</strong> ((WriterPool)getPool()).getSerialNo();
<a name="266" href="#266">266</a>     }
<a name="267" href="#267">267</a> 
<a name="268" href="#268">268</a>     <em>/**<em>*</em></em>
<a name="269" href="#269">269</a> <em>     * Set up pool of files.</em>
<a name="270" href="#270">270</a> <em>     */</em>
<a name="271" href="#271">271</a>     <strong>protected</strong> <strong>abstract</strong> <strong>void</strong> setupPool(<strong>final</strong> AtomicInteger serialNo);
<a name="272" href="#272">272</a> 
<a name="273" href="#273">273</a>     <em>/**<em>*</em></em>
<a name="274" href="#274">274</a> <em>     * Writes a CrawlURI and its associated data to store file.</em>
<a name="275" href="#275">275</a> <em>     *</em>
<a name="276" href="#276">276</a> <em>     * Currently this method understands the following uri types: dns, http, </em>
<a name="277" href="#277">277</a> <em>     * and https.</em>
<a name="278" href="#278">278</a> <em>     *</em>
<a name="279" href="#279">279</a> <em>     * @param curi CrawlURI to process.</em>
<a name="280" href="#280">280</a> <em>     */</em>
<a name="281" href="#281">281</a>     <strong>protected</strong> <strong>abstract</strong> <strong>void</strong> innerProcess(<a href="../../../../org/archive/crawler/datamodel/CrawlURI.html">CrawlURI</a> curi);
<a name="282" href="#282">282</a>     
<a name="283" href="#283">283</a>     <strong>protected</strong> <strong>void</strong> checkBytesWritten() {
<a name="284" href="#284">284</a>         <strong>long</strong> max = getMaxToWrite();
<a name="285" href="#285">285</a>         <strong>if</strong> (max &lt;= 0) {