This PR adds per-field metadata that can be set in the mappings and is later
returned by the field capabilities API. This metadata is completely opaque to
Elasticsearch but may be used by tools that index data in Elasticsearch to
communicate metadata about fields with tools that then search this data. A
typical example that has been requested in the past is the ability to attach
a unit to a numeric field.
In order to not bloat the cluster state, Elasticsearch requires that this
metadata be small:
- keys can't be longer than 20 chars,
- values can only be numbers or strings of no more than 50 chars - no inner
arrays or objects,
- the metadata can't have more than 5 keys in total.
Given that metadata is opaque to Elasticsearch, field capabilities don't try to
do anything smart when merging metadata about multiple indices, the union of
all field metadatas is returned.
Here is how the meta might look like in mappings:
```json
{
"properties": {
"latency": {
"type": "long",
"meta": {
"unit": "ms"
}
}
}
}
```
And then in the field capabilities response:
```json
{
"latency": {
"long": {
"searchable": true,
"aggreggatable": true,
"meta": {
"unit": [ "ms" ]
}
}
}
}
```
When there are no conflicts, values are arrays of size 1, but when there are
conflicts, Elasticsearch includes all unique values in this array, without
giving ways to know which index has which metadata value:
```json
{
"latency": {
"long": {
"searchable": true,
"aggreggatable": true,
"meta": {
"unit": [ "ms", "ns" ]
}
}
}
}
```
Closes#33267
This commit moves the documentation and examples for the `index_prefixes`
option on text fields to its own file, to bring it in line with other mapping
parameters, and expands a bit on both.
Currently global ordinals are documented under `fielddata`. It moves them to
their own file since they also work with doc values and fielddata is on the way
out.
Closes#23101
Since `_all` is now deprecated and cannot be set for new indices, we should also
disallow any field that has the `include_in_all` parameter set.
Resolves#22923
This adds a new `normalizer` property to `keyword` fields that pre-processes the
field value prior to indexing, but without altering the `_source`. Note that
only the normalization components that work on a per-character basis are
applied, so for instance stemming filters will be ignored while lowercasing or
ascii folding will be applied.
Closes#18064
With the cut over to LatLonPoint the geohash, geohash_precision, lat_lon, and geohash_prefix parameters have been removed. This commit fixes the doc build by removing the remaining dangling references to these removed parameters.
Adds infrastructure so `gradle :docs:check` will extract tests from
snippets in the documentation and execute the tests. This is included
in `gradle check` so it should happen on CI and during a normal build.
By default each `// AUTOSENSE` snippet creates a unique REST test. These
tests are executed in a random order and the cluster is wiped between
each one. If multiple snippets chain together into a test you can annotate
all snippets after the first with `// TEST[continued]` to have the
generated tests for both snippets joined.
Snippets marked as `// TESTRESPONSE` are checked against the response
of the last action.
See docs/README.asciidoc for lots more.
Closes#12583. That issue is about catching bugs in the docs during build.
This catches *some* bugs in the docs during build which is a good start.