Simple HTTP/TCP health check for MongoDB

Question

I need to create a Health Check for a MongoDB instance inside a Docker container.

Although I can make a workaround and use the Mongo Ping using the CLI, the best option is to create a simple HTTP or TCP testing. There is no response in the default 27017 port in standard ping testings.

Is there any trustworthy way to do it?

Answer 1

I've created a simple health check for mongodb, it uses the mongo client to send a simple query request (eg. db.stats()) to the server.

$ mongo 192.168.5.51:30000/test

MongoDB shell version: 3.2.3
connecting to: 192.168.5.51:30000/test

mongos> db.stats()
{
    "raw" : {
        "set1/192.168.5.52:27000,192.168.5.53:27000" : {
            "db" : "test",
            "collections" : 8,
            "objects" : 50,
            "avgObjSize" : 73.12,
            "dataSize" : 3656,
            "storageSize" : 53248,
            "numExtents" : 8,
            "indexes" : 8,
            "indexSize" : 65408,
            "fileSize" : 469762048,
            "nsSizeMB" : 16,
            "dataFileVersion" : {
                "major" : 4,
                "minor" : 6
            },
            "extentFreeList" : {
                "num" : 28,
                "totalSize" : 184807424
            },
            "ok" : 1
        }
    },
    "objects" : 50,
    "avgObjSize" : 73,
    "dataSize" : 3656,
    "storageSize" : 53248,
    "numExtents" : 8,
    "indexes" : 8,
    "indexSize" : 65408,
    "fileSize" : 469762048,
    "extentFreeList" : {
        "num" : 28,
        "totalSize" : 184807424
    },
    "ok" : 1
}

You can also do this in one line:

$ echo 'db.stats().ok' | mongo 192.168.5.51:30000/test --quiet
1

Hope it's help.

UPDATE:

As @luckydonald said, the ping command is better, so you can do it like:

$ mongo --eval 'db.runCommand("ping").ok' localhost:27017/test --quiet
1

Thanks for @luckydonald.