[discrete] [[breaking_70_api_changes]] === API changes //NOTE: The notable-breaking-changes tagged regions are re-used in the //Installation and Upgrade Guide //tag::notable-breaking-changes[] // end::notable-breaking-changes[] [discrete] ==== Internal Versioning is no longer supported for optimistic concurrency control Elasticsearch maintains a numeric version field for each document it stores. That field is incremented by one with every change to the document. Until 7.0.0 the API allowed using that field for optimistic concurrency control, i.e., making a write operation conditional on the current document version. Sadly, that approach is flawed because the value of the version doesn't always uniquely represent a change to the document. If a primary fails while handling a write operation, it may expose a version that will then be reused by the new primary. Due to that issue, internal versioning can no longer be used and is replaced by a new method based on sequence numbers. See <> for more details. Note that the `external` versioning type is still fully supported. [discrete] ==== Camel case and underscore parameters deprecated in 6.x have been removed A number of duplicate parameters deprecated in 6.x have been removed from Bulk request, Multi Get request, Term Vectors request, and More Like This Query requests. The following camel case parameters have been removed: * `opType` * `versionType`, `_versionType` The following parameters starting with underscore have been removed: * `_parent` * `_retry_on_conflict` * `_routing` * `_version` * `_version_type` Instead of these removed parameters, use their non camel case equivalents without starting underscore, e.g. use `version_type` instead of `_version_type` or `versionType`. [discrete] ==== Thread pool info In previous versions of Elasticsearch, the thread pool info returned in the <> returned `min` and `max` values reflecting the configured minimum and maximum number of threads that could be in each thread pool. The trouble with this representation is that it does not align with the configuration parameters used to configure thread pools. For <>, the minimum number of threads is configured by a parameter called `core` and the maximum number of threads is configured by a parameter called `max`. For <>, there is only one configuration parameter along these lines and that parameter is called `size`, reflecting the fixed number of threads in the pool. This discrepancy between the API and the configuration parameters has been rectified. Now, the API will report `core` and `max` for scaling thread pools, and `size` for fixed thread pools. Similarly, in the cat thread pool API the existing `size` output has been renamed to `pool_size` which reflects the number of threads currently in the pool; the shortcut for this value has been changed from `s` to `psz`. The `min` output has been renamed to `core` with a shortcut of `cr`, the shortcut for `max` has been changed to `mx`, and the `size` output with a shortcut of `sz` has been reused to report the configured number of threads in the pool. This aligns the output of the API with the configuration values for thread pools. Note that `core` and `max` will be populated for scaling thread pools, and `size` will be populated for fixed thread pools. [discrete] [[fields-param-removed-bulk-update-request]] ==== The parameter `fields` deprecated in 6.x has been removed from Bulk request and Update request. The Update API returns `400 - Bad request` if request contains unknown parameters (instead of ignored in the previous version). [discrete] ==== PUT Document with Version error message changed when document is missing If you attempt to `PUT` a document with versioning (e.g. `PUT /test/_doc/1?version=4`) but the document does not exist, a cryptic message is returned: [source,text] ---------- version conflict, current version [-1] is different than the one provided [4] ---------- Now if the document is missing a more helpful message is returned: [source,text] ---------- document does not exist (expected version [4]) ---------- Although exceptions messages are liable to change and not generally subject to backwards compatibility, the nature of this message might mean clients are relying on parsing the version numbers and so the format change might impact some users. [discrete] [[remove-suggest-metric]] ==== Remove support for `suggest` metric/index metric in indices stats and nodes stats APIs Previously, `suggest` stats were folded into `search` stats. Support for the `suggest` metric on the indices stats and nodes stats APIs remained for backwards compatibility. Backwards support for the `suggest` metric was deprecated in 6.3.0 and now removed in 7.0.0. [discrete] [[remove-field-caps-body]] ==== Field capabilities request format In the past, `fields` could be provided either as a parameter, or as part of the request body. Specifying `fields` in the request body as opposed to a parameter was deprecated in 6.4.0, and is now unsupported in 7.0.0. [discrete] [[copy-settings-deprecated-shrink-split-apis]] ==== `copy_settings` is deprecated on shrink and split APIs Versions of Elasticsearch prior to 6.4.0 did not copy index settings on shrink and split operations. Starting with Elasticsearch 7.0.0, the default behavior will be for such settings to be copied on such operations. To enable users in 6.4.0 to transition in 6.4.0 to the default behavior in 7.0.0, the `copy_settings` parameter was added on the REST layer. As this behavior will be the only behavior in 8.0.0, this parameter is deprecated in 7.0.0 for removal in 8.0.0. [discrete] ==== The deprecated stored script contexts have now been removed When putting stored scripts, support for storing them with the deprecated `template` context or without a context is now removed. Scripts must be stored using the `script` context as mentioned in the documentation. [discrete] ==== Removed Get Aliases API limitations when {security-features} are enabled The behavior and response codes of the get aliases API no longer vary depending on whether {security-features} are enabled. Previously a 404 - NOT FOUND (IndexNotFoundException) could be returned in case the current user was not authorized for any alias. An empty response with status 200 - OK is now returned instead at all times. [discrete] [[user-object-removed-put-user-api]] ==== Put User API response no longer has `user` object The Put User API response was changed in 6.5.0 to add the `created` field outside of the user object where it previously had been. In 7.0.0 the user object has been removed in favor of the top level `created` field. [discrete] [[source-include-exclude-params-removed]] ==== Source filtering url parameters `_source_include` and `_source_exclude` have been removed The deprecated in 6.x url parameters are now removed. Use `_source_includes` and `_source_excludes` instead. [discrete] ==== Multi Search Request metadata validation MultiSearchRequests issued through `_msearch` now validate all keys in the metadata section. Previously unknown keys were ignored while now an exception is thrown. [discrete] ==== Deprecated graph endpoints removed The deprecated graph endpoints (those with `/_graph/_explore`) have been removed. [discrete] [[deprecated-termvector-endpoint-removed]] ==== Deprecated `_termvector` endpoint removed The `_termvector` endpoint was deprecated in 2.0 and has now been removed. The endpoint `_termvectors` (plural) should be used instead. [discrete] ==== When {security-features} are enabled, index monitoring APIs over restricted indices are not authorized implicitly anymore Restricted indices (currently only `.security-6` and `.security`) are special internal indices that require setting the `allow_restricted_indices` flag on every index permission that covers them. If this flag is `false` (default) the permission will not cover these and actions against them will not be authorized. However, the monitoring APIs were the only exception to this rule. This exception has been forfeited and index monitoring privileges have to be granted explicitly, using the `allow_restricted_indices` flag on the permission (as any other index privilege). [discrete] [[remove-get-support-cache-clear-api]] ==== Removed support for `GET` on the `_cache/clear` API The `_cache/clear` API no longer supports the `GET` HTTP verb. It must be called with `POST`. [discrete] ==== Cluster state size metrics removed from Cluster State API Response The `compressed_size` / `compressed_size_in_bytes` fields were removed from the Cluster State API response. The calculation of the size was expensive and had dubious value, so the field was removed from the response. [discrete] ==== Migration Assistance API has been removed The Migration Assistance API has been functionally replaced by the Deprecation Info API, and the Migration Upgrade API is not used for the transition from ES 6.x to 7.x, and does not need to be kept around to repair indices that were not properly upgraded before upgrading the cluster, as was the case in 6. [discrete] ==== Changes to thread pool naming in Node and Cat APIs The `thread_pool` information returned from the Nodes and Cat APIs has been standardized to use the same terminology as the thread pool configurations. This means the response will align with the configuration instead of being the same across all the thread pools, regardless of type. [discrete] ==== Return 200 when cluster has valid read-only blocks If the cluster was configured with `no_master_block: write` and lost its master, it would return a `503` status code from a main request (`GET /`) even though there are viable read-only nodes available. The cluster now returns 200 status in this situation. [discrete] ==== Clearing indices cache is now POST-only Clearing the cache indices could previously be done via GET and POST. As GET should only support read only non state-changing operations, this is no longer allowed. Only POST can be used to clear the cache.