tellem
----

tellem dsl for extracting telemetry from json and xml and any other input that has a path lang for extracting content from messages

### NOTES

* first implementation in scala and antlr
* embeddable
* uses jsonpath for first impl, xpath eventually, support for other path langs should be plugable
* eventual support of first class logic programming as an ai frontend

### FEATURES

1. variables
2. assertions
3. yield template

* keywords: set, def, assert, template, int, string, float, datetime, eq, ne, lt, gt, lte, gte, pathlang, now
* comments follow # to end of line
* use 'now' if you want clock time as telemetry time
* in the future, will support basic math in an assertion like totalCount / goodCount
* whitespace within a line is ignored
* a tellem defines any number of variables with paths
* all variables are optional types of either string, int, float, or datetime
* a tellem defines any number of assertions that reference the variables
* an assertion that references a variable that isEmpty returns false
* an assertion can use eq, ne, gt, lt, lte, gte
* there is one implicit assertion: all variables musts resolve
* if all the assertions are true, a record is formatted and yielded

### EXAMPLE

```
set datetime yyy-mo-dd'T'hh-mm-ss.SSSZ
set pathlang jsonpath

def device:   str($.machineId)
def time:     datetime($.datetime)
def msgType:  str($.payload.type)
def totalOps: int($.payload.opevent.totalCount)
def goodOps:  int($.payload.opevent.successCount)

assert msgType  eq str(opEvent)
assert totalOps gt int(12)
assert goodOps  lt int(10)

template {time} {goodOps} my.telemetry.record.for.device.{device}.lowgoodops.alert

```