I have an aggregation query. In the $addToFields
stage of the query I need to add another field that is a regex of another field. For example, here is an example document:
{
"host": "axcc91-calpw-11299",
"site": "gate9",
"type": "router"
}
I need to apply this regex: ^([^-\d]+)
which will produce axcc from the above document. Here is the document i need produced:
{
"host": "axcc91-calpw-11299",
"site": "gate9",
"type": "router",
"host2": "axcc"
}
How would I apply a regex to either a $project or $addToFields stage to produce the host2 field?