func whereFilter(where expr.Node, task TaskRunner, cols map[string]*expr.Column) MessageHandler {
out := task.MessageOut()
evaluator := vm.Evaluator(where)
return func(ctx *Context, msg datasource.Message) bool {
var whereValue value.Value
var ok bool
switch mt := msg.(type) {
case *datasource.SqlDriverMessage:
//u.Debugf("WHERE: T:%T vals:%#v", msg, mt.Vals)
//u.Debugf("cols: %#v", cols)
msgReader := datasource.NewValueContextWrapper(mt, cols)
whereValue, ok = evaluator(msgReader)
case *datasource.SqlDriverMessageMap:
whereValue, ok = evaluator(mt)
//u.Debugf("WHERE: result:%v T:%T vals:%#v", whereValue, msg, mt.Values())
//u.Debugf("cols: %#v", cols)
default:
if msgReader, ok := msg.(expr.ContextReader); ok {
whereValue, ok = evaluator(msgReader)
} else {
u.Errorf("could not convert to message reader: %T", msg)
}
}
//u.Debugf("msg: %#v", msgReader)
//u.Infof("evaluating: ok?%v result=%v where expr:%v", ok, whereValue.ToString(), where.StringAST())
if !ok {
u.Debugf("could not evaluate: %v", msg)
return false
}
switch whereVal := whereValue.(type) {
case value.BoolValue:
if whereVal.Val() == false {
//u.Debugf("Filtering out: T:%T v:%#v", whereVal, whereVal)
return true
}
case nil:
return false
default:
if whereVal.Nil() {
return false
}
}
//u.Debugf("about to send from where to forward: %#v", msg)
select {
case out <- msg:
return true
case <-task.SigChan():
return false
}
}
}
func joinValue(ctx *Context, node expr.Node, msg datasource.Message, cols map[string]*expr.Column) (string, bool) {
if msg == nil {
u.Warnf("got nil message?")
}
//u.Infof("got message: %T %#v", msg, cols)
switch mt := msg.(type) {
case *datasource.SqlDriverMessage:
msgReader := datasource.NewValueContextWrapper(mt, cols)
joinVal, ok := vm.Eval(msgReader, node)
//u.Debugf("msg: %#v", msgReader)
//u.Debugf("evaluating: ok?%v T:%T result=%v node '%v'", ok, joinVal, joinVal.ToString(), node.String())
if !ok {
u.Errorf("could not evaluate: %T %#v %v", joinVal, joinVal, msg)
return "", false
}
switch val := joinVal.(type) {
case value.StringValue:
return val.Val(), true
default:
u.Warnf("unknown type? %T", joinVal)
}
default:
if msgReader, ok := msg.Body().(expr.ContextReader); ok {
joinVal, ok := vm.Eval(msgReader, node)
//u.Debugf("msg: %#v", msgReader)
//u.Infof("evaluating: ok?%v T:%T result=%v node expr:%v", ok, joinVal, joinVal.ToString(), node.StringAST())
if !ok {
u.Errorf("could not evaluate: %v", msg)
return "", false
}
switch val := joinVal.(type) {
case value.StringValue:
return val.Val(), true
default:
u.Warnf("unknown type? %T", joinVal)
}
} else {
u.Errorf("could not convert to message reader: %T", msg.Body())
}
}
return "", false
}