Cannot execute a gradlew task that eventually starts an embedded Mongo twice on Windows

Reproduction steps:

1. Install Java 8
2. Clone the repository at https://github.com/hiddenswitch/Spellsource-Server
3. In Windows Powershell, run & ".\gradlew.bat net:local.
4. Observe de.flapdoodle.embed.mongo correctly downloads and executes a mongod.
5. SIGINT the process with Shift+Ctrl+C
6. In Windows Powershell, run & ".\gradlew.bat net:local.
7. Observe the following exception:

10:15:37.426 [main] ERROR d.f.e.p.runtime.AbstractProcess - failed to call onAfterProcessStart()
java.io.IOException: Could not start process: <EOF>
        at de.flapdoodle.embed.mongo.AbstractMongoProcess.onAfterProcessStart(AbstractMongoProcess.java:79) [de.flapdoodle.embed.mongo-e5232204c2.jar:na]
        at de.flapdoodle.embed.process.runtime.AbstractProcess.<init>(AbstractProcess.java:114) ~[de.flapdoodle.embed.process-2.0.1.jar:na]
        at de.flapdoodle.embed.mongo.AbstractMongoProcess.<init>(AbstractMongoProcess.java:53) [de.flapdoodle.embed.mongo-e5232204c2.jar:na]
        at de.flapdoodle.embed.mongo.MongodProcess.<init>(MongodProcess.java:50) [de.flapdoodle.embed.mongo-e5232204c2.jar:na]
        at de.flapdoodle.embed.mongo.MongodExecutable.start(MongodExecutable.java:44) [de.flapdoodle.embed.mongo-e5232204c2.jar:na]
        at de.flapdoodle.embed.mongo.MongodExecutable.start(MongodExecutable.java:34) [de.flapdoodle.embed.mongo-e5232204c2.jar:na]
        at de.flapdoodle.embed.process.runtime.Executable.start(Executable.java:101) [de.flapdoodle.embed.process-2.0.1.jar:na]
        at com.hiddenswitch.spellsource.util.LocalMongo.start(LocalMongo.java:66) [main/:na]
        at com.hiddenswitch.spellsource.util.Mongo.startEmbedded(Mongo.java:47) [main/:na]
        at com.hiddenswitch.spellsource.util.Mongo.connectWithEnvironment(Mongo.java:102) [main/:na]
        at com.hiddenswitch.spellsource.applications.Embedded.main(Embedded.java:22) [main/:na]
Mongo failed to start.
java.io.IOException: Could not start process: <EOF>
        at de.flapdoodle.embed.mongo.AbstractMongoProcess.onAfterProcessStart(AbstractMongoProcess.java:79)
        at de.flapdoodle.embed.process.runtime.AbstractProcess.<init>(AbstractProcess.java:114)
        at de.flapdoodle.embed.mongo.AbstractMongoProcess.<init>(AbstractMongoProcess.java:53)
        at de.flapdoodle.embed.mongo.MongodProcess.<init>(MongodProcess.java:50)
        at de.flapdoodle.embed.mongo.MongodExecutable.start(MongodExecutable.java:44)
        at de.flapdoodle.embed.mongo.MongodExecutable.start(MongodExecutable.java:34)
        at de.flapdoodle.embed.process.runtime.Executable.start(Executable.java:101)
        at com.hiddenswitch.spellsource.util.LocalMongo.start(LocalMongo.java:66)
        at com.hiddenswitch.spellsource.util.Mongo.startEmbedded(Mongo.java:47)
        at com.hiddenswitch.spellsource.util.Mongo.connectWithEnvironment(Mongo.java:102)
        at com.hiddenswitch.spellsource.applications.Embedded.main(Embedded.java:22)

1. Delete the net\.mongo directory.
2. Observe running & ".\gradlew.bat" net:local despite even deleting the directory does not resolve the issue.
3. Observe restarting the computer does not resolve the issue.
4. Observe that an equivalent sequence of steps produces no issues on Mac or Linux.

Thoughts?

[bertramn]

I am able to reproduce the issue on Windows 7 with flapdoodle mongo version 2.0.1 which defaults to mongo version 3.6.0. From what I can tell is that MongoDB 3.6.x needs libeay32.dll and ssleay32.dll. Unless both are available on the PATH the error above matches what I can see.

The flapdoodle process extracts the mongod.exe from the zip and copies it to %TEMP%. From mongo 3.6.0, it will also have to copy the 2 dlls to that location or probably less prone to interference, create a sub directory in %TEMP% and extract all 3 files to it.

So to fix it temporarily just download the win zip distro from mongo website and extract the above dlls to %TEMP% folder which is something like C:\Users\fred\AppData\Local\Temp.

[michaelmosmann]

… if this is still an issue, please reopen.