ES-compatible API

[guilload]

Endpoints:

• Setup Elastic _search endpoint #2656
• _msearch endpoint
• Target multiple indexes during a search #2770 (high priority)
• Support elasticsearch field capabilities endpoint #3527
• Support indices-stats elasticsearch endpoint #3526
• Support cat-indices elasticsearch endpoint #3525

Search parameters:

• Support Elasticsearch Scroll API #3551 (high priority)
• Sort by two fields #2670 (high priority)
• ES API does not fully support ES sort API #3310
• Support elasticsearch search_after parameter in a search query #3523 (under discussion)

Query DSL:

• Add support for ES exists query #3263 (high priority)
• Query string with lenient, default_field, fields params (high priority)
• Multi-match query with [phrase_prefix, phrase] type, lenient (high priority)
• Terms query note this is mildly different from term query. (s) (high priority)
  - [Multi-match query with analyze_wildcard + analyzer (under discussion)
• Match all {"match_all": {}}
• Implement the Elastic Bool query #2657
• Query string
• Match query
• Query Phrase Prefix #2266
• Range query
• Sort

Aggregation DSL:

• Date histogram
• Histogram
• Percentiles aggregation
• Terms aggregation
• Stats aggregation

Other missing elastic features that we might discuss:

• Support sort on multiple fields & different types of sort https://www.elastic.co/guide/en/elasticsearch/reference/8.6/sort-search-results.html (under discussion)
• Support selecting/excluding specific document source fields to display (under discussion)

[guilload]

Bumping priority for:

• Query string with analyze_wildcard => under discussion
• Multi-match query

[esatterwhite]

One thing I'm noticing missing from the _search api is the ability to search across multiple indicies

// curl -XPOST http://localhost:7200/api/v1/_elastic/ac*/_search -d '{"query": { "match_all": {} }, "size": 1}'
{
  "status": 404,
  "error": {
    "caused_by": null,
    "reason": "Index `ac*` does not exist.",
    "stack_trace": null,
    "type": null
  }
}

// curl -XPOST http://localhost:7200/api/v1/_elastic/foo,bar/_search -d '{"query": { "match_all": {} }, "size": 1}'
{
  "message": "Route not found"
}

[fmassot]

Thanks for the feedback. Just confirming that search across multiple indices is not yet supported.

[esatterwhite]

The Validation for index names is a little different than what elasticsearch allows.

^[a-zA-Z][a-zA-Z0-9-_]{2,254}$ doesn't allow for a dot (period) . Which is allowed and common in elastic index names.

[esatterwhite]

It looks like the _bulk endpoint is lacking the ability to create missing indexes as well

[esatterwhite]

It looks like the / endpoint will need to support the http method HEAD. As far as I can tell, most elasticsearch client do this when trying to establish a connection to verify the server is responsive.

[fulmicoton]

Commenting about the HEAD request. @fmassot fixed it.

[esatterwhite]

I think we can probably call this done for our purposes @fulmicoton, what do you thin?

[fulmicoton]

If you have everything you need I think we can close it yes!