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<div class="">Hi All</div>
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<div class="">This is more of an FYI...</div>
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<div class="">I have a Cowboy application that does the following during start up:</div>
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<li class="">Start <a href="https://github.com/cmullaparthi/ibrowse" class="">iBrowse</a></li><li class="">Use iBrowse to make an HTTP request to download a text file containing country information</li><li class="">Parse text file to create a list of countries</li><li class="">Start Cowboy and define routes</li><li class="">Start supervisor passing it the list of countries</li><li class="">Supervisor waits for HTTP requests…</li></ol>
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<div class="">This all works nicely.</div>
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<div class="">I’m now extending the functionality to include a MongoDB. </div>
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<div class="">At first, I modified the startup sequence to this:</div>
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<li class="">Connect to MongoDB instance and get pid of db server</li><li class="">Start <a href="https://github.com/cmullaparthi/ibrowse" class="">iBrowse</a></li><li class="">Use iBrowse to make an HTTP request to download a text file containing country information</li><li class="">Parse text file to create a list of countries</li><li class="">Start Cowboy and define routes</li><li class="">Start supervisor passing it the list of countries and MongoDB pid</li><li class="">Supervisor waits for HTTP requests…</li></ol>
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<div class="">If the MongoDB instance is up, then no problem. However, if the MongoDB instance is down, then step 1 returns the expected
<font face="Monaco" class="">{error, econnrefused}</font> when calling <font face="Monaco" class="">
mc_worker_api:connect/1</font> and the db server pid defaults to <font face="Monaco" class="">
undefined</font>. Again, this is all as expected...</div>
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<div class="">But the weird thing is that if the connection to MongoDB fails, then step 3 subsequently fails when iBrowse tries to download the text file. The specific failure is <font face="Monaco" class="">badarg</font> when calling
<font face="Monaco" class="">ets:lookup/2</font> in line 345 of <font face="Monaco" class="">
ibrowse.erl</font>.</div>
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<div class="">This doesn’t make much sense to me at all because the two libraries should be unrelated.</div>
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<div class="">I can make the problem go away by moving the code that connects to MongoDB to be after the iBrowse request, but to me, the weirdness of this error highlights that there might be some underlying problem with the MongoDB library and ets.</div>
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<div class="">Regards</div>
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