A StringTemplate4 Akka Streams source producing template driven test data

See stringtemplate4.

USAGE

update your build.sbt dependencies with:

// https://mvnrepository.com/artifact/tech.navicore/stsource
libraryDependencies += "tech.navicore" %% "stsource" % "1.1.0"

Use any ST group file - assuming UTF8 and '<' '>' delimiters. For example, /iotjson.stg:

decl(type, deviceId, module, value) ::= "{<initType(type)>, <initDeviceId(deviceId)>, <initModule(module)>, <initValue(value)>}"
initType(v) ::= "<if(v)>\"type\": \"<v>\"<endif>"
initDeviceId(v) ::= "<if(v)>\"deviceId\": \"<v>\"<endif>"
initModule(v) ::= "<if(v)>\"module\": \"<v>\"<endif>"
initValue(v) ::= "<if(v)>\"value\": <v><endif>"

Create a config and a source as in the example below.

    import navicore.akka.stsource._
    ...
    ...
    ...
    val consumer = ... // some Sink that prints `String` input to console
    ...
    ...
    ...
    val stgUrl: URL = getClass.getResource("/iotjson.stg")
    implicit val cfg: StConfig =
      StConfig(100,                        // 100 lines, use 0 for infinite
               stgUrl,
               Map(
                 ("type", List("observation", "error", "heartbeat")),
                 ("deviceId", List("d1", "d2", "d3", "d4")),
                 ("module", List("temp1", "temp2", "waterLvl1")),
                 ("value", List("24.0", "20.8", "19.0", "68.1"))
               ))
    val src = StSource()
    ...
    ...
    ...
    src.runWith(consumer)
    ...
    ...
    ...

Above produces 100 lines like below:

{"type": "error", "deviceId": "d4", "module": "temp2", "value": 68.1}
{"type": "heartbeat", "deviceId": "d2", "module": "waterLvl1", "value": 20.8}
{"type": "error", "deviceId": "d3", "module": "temp2", "value": 19.0}
{"type": "heartbeat", "deviceId": "d3", "module": "waterLvl1", "value": 19.0}
{"type": "observation", "deviceId": "d1", "module": "temp1", "value": 24.0}
{"type": "error", "deviceId": "d4", "module": "temp2", "value": 68.1}
{"type": "observation", "deviceId": "d1", "module": "temp1", "value": 24.0}
{"type": "heartbeat", "deviceId": "d4", "module": "waterLvl1", "value": 68.1}
{"type": "error", "deviceId": "d2", "module": "temp2", "value": 20.8}
{"type": "heartbeat", "deviceId": "d3", "module": "waterLvl1", "value": 19.0}
{"type": "error", "deviceId": "d3", "module": "temp2", "value": 19.0}
{"type": "heartbeat", "deviceId": "d2", "module": "waterLvl1", "value": 20.8}
{"type": "error", "deviceId": "d4", "module": "temp2", "value": 68.1}
{"type": "error", "deviceId": "d1", "module": "temp2", "value": 24.0}
{"type": "observation", "deviceId": "d3", "module": "temp1", "value": 19.0}
{"type": "heartbeat", "deviceId": "d4", "module": "waterLvl1", "value": 68.1}
{"type": "error", "deviceId": "d1", "module": "temp2", "value": 24.0}

TODO

1. support stg file paths in addition to URL.
2. support abstract stg file sources instead of ST's current requirement of a file path or URL - might require a fork of StringTemplate4.

OPS

publish local

sbt +publishLocalSigned

publish to nexus staging

export GPG_TTY=$(tty)
sbt +publishSigned
sbt sonatypeReleaseAll

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