Parsing JSON output in Shell script
jq is a useful utility to parse JSON output in a shell script
jq can be downloaded as a binary and scp'ed to any host and it works just fine.
For more info on jq refer http://stedolan.github.io/jq/
Let us put that to work. The following curl command throws up a JSON output
# curl -s http://localhost:12345/metrics
{"SOURCE.scribeSrc":{"OpenConnectionCount":"0","AppendBatchAcceptedCount":"0","AppendBatchReceivedCount":"0","Type":"SOURCE","EventAcceptedCount":"1850929558","AppendReceivedCount":"0","StopTime":"0","EventReceivedCount":"1850929558","StartTime":"1399527923731","AppendAcceptedCount":"0"},"SINK.avroSink3":{"BatchCompleteCount":"1786","ConnectionFailedCount":"8","EventDrainAttemptCount":"463854128","ConnectionCreatedCount":"1135","BatchEmptyCount":"251379","Type":"SINK","ConnectionClosedCount":"1134","EventDrainSuccessCount":"463852531","StopTime":"0","StartTime":"1399527920721","BatchUnderflowCount":"1222487"},"SINK.avroSink2":{"BatchCompleteCount":"1826","ConnectionFailedCount":"8","EventDrainAttemptCount":"464081974","ConnectionCreatedCount":"882","BatchEmptyCount":"251234","Type":"SINK","ConnectionClosedCount":"881","EventDrainSuccessCount":"464080652","StopTime":"0","StartTime":"1399527920721","BatchUnderflowCount":"1226221"},"SINK.avroSink1":{"BatchCompleteCount":"1830","ConnectionFailedCount":"8","EventDrainAttemptCount":"462363915","ConnectionCreatedCount":"882","BatchEmptyCount":"250488","Type":"SINK","ConnectionClosedCount":"881","EventDrainSuccessCount":"462362687","StopTime":"0","StartTime":"1399527920720","BatchUnderflowCount":"1219047"},"SINK.avroSink":{"BatchCompleteCount":"1881","ConnectionFailedCount":"8","EventDrainAttemptCount":"460631266","ConnectionCreatedCount":"882","BatchEmptyCount":"250796","Type":"SINK","ConnectionClosedCount":"881","EventDrainSuccessCount":"460630534","StopTime":"0","StartTime":"1399527920720","BatchUnderflowCount":"1219204"},"CHANNEL.fileChannel":{"EventPutSuccessCount":"1850929558","ChannelFillPercentage":"0.003154","Type":"CHANNEL","StopTime":"0","EventPutAttemptCount":"1850929558","ChannelSize":"3154","StartTime":"1399527920713","EventTakeSuccessCount":"1850926404","ChannelCapacity":"100000000","EventTakeAttemptCount":"1856822139"}}[12:46:23]
To make it readable, let us use jq command
# curl -s http://localhost:12345/metrics | /tmp/jq '.'
{
"CHANNEL.fileChannel": {
"EventTakeAttemptCount": "1857737035",
"ChannelCapacity": "100000000",
"EventPutSuccessCount": "1851841723",
"ChannelFillPercentage": "0.001698",
"Type": "CHANNEL",
"StopTime": "0",
"EventPutAttemptCount": "1851841723",
"ChannelSize": "1698",
"StartTime": "1399527920713",
"EventTakeSuccessCount": "1851840025"
},
"SINK.avroSink": {
"BatchUnderflowCount": "1219720",
"StartTime": "1399527920720",
"StopTime": "0",
"BatchCompleteCount": "1881",
"ConnectionFailedCount": "8",
"EventDrainAttemptCount": "460864030",
"ConnectionCreatedCount": "882",
"BatchEmptyCount": "250852",
"Type": "SINK",
"ConnectionClosedCount": "881",
"EventDrainSuccessCount": "460863849"
},
"SINK.avroSink1": {
"BatchUnderflowCount": "1219539",
"StartTime": "1399527920720",
"StopTime": "0",
"BatchCompleteCount": "1830",
"ConnectionFailedCount": "8",
"EventDrainAttemptCount": "462602212",
"ConnectionCreatedCount": "882",
"BatchEmptyCount": "250540",
"Type": "SINK",
"ConnectionClosedCount": "881",
"EventDrainSuccessCount": "462601149"
},
"SINK.avroSink2": {
"BatchUnderflowCount": "1226686",
"StartTime": "1399527920721",
"StopTime": "0",
"BatchCompleteCount": "1826",
"ConnectionFailedCount": "8",
"EventDrainAttemptCount": "464310084",
"ConnectionCreatedCount": "882",
"BatchEmptyCount": "251284",
"Type": "SINK",
"ConnectionClosedCount": "881",
"EventDrainSuccessCount": "464309471"
},
"SINK.avroSink3": {
"BatchUnderflowCount": "1222934",
"StartTime": "1399527920721",
"StopTime": "0",
"BatchCompleteCount": "1786",
"ConnectionFailedCount": "8",
"EventDrainAttemptCount": "464067716",
"ConnectionCreatedCount": "1135",
"BatchEmptyCount": "251438",
"Type": "SINK",
"ConnectionClosedCount": "1134",
"EventDrainSuccessCount": "464065556"
},
"SOURCE.scribeSrc": {
"AppendAcceptedCount": "0",
"StartTime": "1399527923731",
"OpenConnectionCount": "0",
"AppendBatchAcceptedCount": "0",
"AppendBatchReceivedCount": "0",
"Type": "SOURCE",
"EventAcceptedCount": "1851841723",
"AppendReceivedCount": "0",
"StopTime": "0",
"EventReceivedCount": "1851841723"
}
}
