This change adds a strict mode for xcontent parsing on the rest layer. The strict mode will be off by default for 5.x and in a separate commit will be enabled by default for 6.0. The strict mode, which can be enabled by setting `http.content_type.required: true` in 5.x, will require that all incoming rest requests have a valid and supported content type header before the request is dispatched. In the non-strict mode, the Content-Type header will be inspected and if it is not present or not valid, we will continue with auto detection of content like we have done previously.
The content type header is parsed to the matching XContentType value with the only exception being for plain text requests. This value is then passed on with the content bytes so that we can reduce the number of places where we need to auto-detect the content type.
As part of this, many transport requests and builders were updated to provide methods that
accepted the XContentType along with the bytes and the methods that would rely on auto-detection have been deprecated.
In the non-strict mode, deprecation warnings are issued whenever a request with body doesn't provide the Content-Type header.
See #19388
There are presently 7 ctor args used in any rest handlers:
* `Settings`: Every handler uses it to initialize a logger and
some other strange things.
* `RestController`: Every handler registers itself with it.
* `ClusterSettings`: Used by `RestClusterGetSettingsAction` to
render the default values for cluster settings.
* `IndexScopedSettings`: Used by `RestGetSettingsAction` to get
the default values for index settings.
* `SettingsFilter`: Used by a few handlers to filter returned
settings so we don't expose stuff like passwords.
* `IndexNameExpressionResolver`: Used by `_cat/indices` to
filter the list of indices.
* `Supplier<DiscoveryNodes>`: Used to fill enrich the response
by handlers that list tasks.
We probably want to reduce these arguments over time but
switching construction away from guice gives us tighter
control over the list of available arguments.
These parameters are passed to plugins using
`ActionPlugin#initRestHandlers` which is expected to build and
return that handlers immediately. This felt simpler than
returning an reference to the ctors given all the different
possible args.
Breaks java plugins by moving rest handlers off of guice.
Today when parsing a request, Elasticsearch silently ignores incorrect
(including parameters with typos) or unused parameters. This is bad as
it leads to requests having unintended behavior (e.g., if a user hits
the _analyze API and misspell the "tokenizer" then Elasticsearch will
just use the standard analyzer, completely against intentions).
This commit removes lenient URL parameter parsing. The strategy is
simple: when a request is handled and a parameter is touched, we mark it
as such. Before the request is actually executed, we check to ensure
that all parameters have been consumed. If there are remaining
parameters yet to be consumed, we fail the request with a list of the
unconsumed parameters. An exception has to be made for parameters that
format the response (as opposed to controlling the request); for this
case, handlers are able to provide a list of parameters that should be
excluded from tripping the unconsumed parameters check because those
parameters will be used in formatting the response.
Additionally, some inconsistencies between the parameters in the code
and in the docs are corrected.
Relates #20722
* Build: Remove old maven deploy support
This change removes the old maven deploy that we have in parallel to
maven-publish, and makes maven-publish fully work with publishing to
maven local. Using `gradle publishToMavenLocal` should be used to
publish to .m2.
Note that there is an unfortunate hack that means for
zip artifacts we must first create/publish a dummy pom file, and then
follow that with the real pom file. It would be nice to have the pom
file contains packaging=zip, but maven central then requires sources and
javadocs. But our zips are really just attached artifacts, so we already
set the packaging type to pom for our zip files. This change just works
around a limitation of the underlying maven publishing library which
silently skips attached artifacts when the packaging type is set to pom.
relates #20164closes#20375
* Remove unnecessary extra spacing
This change replaces the fields parameter with stored_fields when it makes sense.
This is dictated by the renaming we made in #18943 for the search API.
The following list of endpoint has been changed to use `stored_fields` instead of `fields`:
* get
* mget
* explain
The documentation and the rest API spec has been updated to cope with the changes for the following APIs:
* delete_by_query
* get
* mget
* explain
The `fields` parameter has been deprecated for the following APIs (it is replaced by _source filtering):
* update: the fields are extracted from the _source directly.
* bulk: the fields parameter is used but fields are extracted from the source directly so it is allowed to have non-stored fields.
Some APIs still have the `fields` parameter for various reasons:
* cat.fielddata: the fields paramaters relates to the fielddata fields that should be printed.
* indices.clear_cache: used to indicate which fielddata fields should be cleared.
* indices.get_field_mapping: used to filter fields in the mapping.
* indices.stats: get stats on fields (stored or not stored).
* termvectors: fields are retrieved from the stored fields if possible and extracted from the _source otherwise.
* mtermvectors:
* nodes.stats: the fields parameter is used to concatenate completion_fields and fielddata_fields so it's not related to stored_fields at all.
Fixes#20155
Jay Modi
Nik Everett
javanna
Luca Cavanna
Ryan Ernst
Areek Zillur
Jason Tedor
Jim Ferenczi
Daniel Mitterdorfer
Daniel Mitterdorfer