Unable to load data in druid - druid

Question

I am a newbie in druid. Trying to load a very simple data in JSON format to druid. The data contains just one dimension, one metric and timestamp. I have been successfully able to load data to druid for a different dataset but somehow I am getting errors for this dataset.
This is my index file :
{
"type" : "index",
"spec" : {
"dataSchema" : {
"dataSource" : "datatemplate",
"parser" : {
"type" : "string",
"parseSpec" : {
"format" : "json",
"dimensionsSpec" : {
"dimensions" : [
"Loc"
]
},
"timestampSpec" : {
"format" : "auto",
"column" : "Timestamp"
}
}
},
"metricsSpec" : [{"name" : "Qty","type" : "doubleSum","fieldName" : "Qty"}],
"granularitySpec" : {
"type" : "uniform",
"segmentGranularity" : "day",
"queryGranularity" : "none",
"intervals" : ["2016-01-01T00:00:00Z/2030-06-30T00:00:00Z"],
"rollup" : true
}
},
"ioConfig" : {
"type" : "index",
"firehose" : {
"type" : "local",
"baseDir" : "datatemplate/",
"filter" : "datatemplate.json"
},
"appendToExisting" : false
},
"tuningConfig" : {
"type" : "index",
"targetPartitionSize" : 10000000,
"maxRowsInMemory" : 40000,
"forceExtendableShardSpecs" : true
}
}
}
Also here is my dataset in JSON format:
{"Loc": "A", "Qty": "1", "Timestamp": "2017-12-01T00:00:00Z"}
{"Loc": "A", "Qty": "1", "Timestamp": "2017-12-01T00:00:00Z"}
{"Loc": "B", "Qty": "2", "Timestamp": "2017-12-01T00:00:00Z"}
{"Loc": "B", "Qty": "1", "Timestamp": "2017-12-01T00:00:00Z"}