ES error: Limit of mapping depth [20] has been exceeded

[abitmore]

Bug Description

The develop branch is unable to sync if ElasticSearch plugin is enabled. Error message:

{"index":{"_index":"btsdev-mainnet-his-2016-05","_type":"_doc","_id":"2.9.3018878","status":400,"error":{"type":"illegal_argument_exception","reason":"Limit of mapping depth [20] has been exceeded due to object field [operation_history.op_object.proposed_ops_object.op_object.data_object.proposed_ops_object.op_object.data_object.proposed_ops_object.op_object.data_object.proposed_ops_object.op_object.data_object.proposed_ops_object.op_object.data_object.proposed_ops_object.op_object.data_object]"}}}

The operation was in block number 6394824:

[22,{"fee":{"amount":2315394,"asset_id":"1.3.0"},"fee_paying_account":"1.2.121","expiration_time":"2016-06-20T00:00:00","proposed_ops":[{"op":[22,{"fee":{"amount":2299628,"asset_id":"1.3.0"},"fee_paying_account":"1.2.121","expiration_time":"2016-06-22T00:00:00","proposed_ops":[{"op":[22,{"fee":{"amount":2283863,"asset_id":"1.3.0"},"fee_paying_account":"1.2.121","expiration_time":"2016-06-23T00:00:00","proposed_ops":[{"op":[22,{"fee":{"amount":2268097,"asset_id":"1.3.0"},"fee_paying_account":"1.2.121","expiration_time":"2016-06-24T00:00:00","proposed_ops":[{"op":[22,{"fee":{"amount":2252331,"asset_id":"1.3.0"},"fee_paying_account":"1.2.121","expiration_time":"2015-06-24T00:00:00","proposed_ops":[{"op":[22,{"fee":{"amount":2236566,"asset_id":"1.3.0"},"fee_paying_account":"1.2.121","expiration_time":"2015-06-24T00:00:00","proposed_ops":[{"op":[12,{"fee":{"amount":100000000,"asset_id":"1.3.0"},"issuer":"1.2.0","asset_to_update":"1.3.113","new_options":{"feed_lifetime_sec":86400,"minimum_feeds":7,"force_settlement_delay_sec":86400,"force_settlement_offset_percent":100,"maximum_force_settlement_volume":50,"short_backing_asset":"1.3.0","extensions":{}},"extensions":[]}]}],"review_period_seconds":3600,"extensions":[]}]}],"review_period_seconds":3600,"extensions":[]}]}],"review_period_seconds":3600,"extensions":[]}]}],"review_period_seconds":3600,"extensions":[]}]}],"review_period_seconds":3600,"extensions":[]}]}],"review_period_seconds":3600,"extensions":[]}]

I believe it was introduced in #2565.

According to ES docs(https://www.elastic.co/guide/en/elasticsearch/reference/7.16/mapping-settings-limit.html), the setting can be updated if really required,

index.mapping.depth.limit - The maximum depth for a field, which is measured as the number of inner objects. For instance, if all fields are defined at the root object level, then the depth is 1. If there is one object mapping, then the depth is 2, etc. The default is 20.

Impacts
Describe which portion(s) of BitShares Core may be impacted by this bug. Please tick at least one box.

• API (the application programming interface)
• Build (the build process or something prior to compiled code)
• CLI (the command line wallet)
• Deployment (the deployment process after building such as Docker, Travis, etc.)
• DEX (the Decentralized EXchange, market engine, etc.)
• P2P (the peer-to-peer network for transaction/block propagation)
• Performance (system or user efficiency, etc.)
• Protocol (the blockchain logic, consensus, validation, etc.)
• Security (the security of system or user data, etc.)
• UX (the User Experience)
• Other (please add below): ElasticSearch plugin

CORE TEAM TASK LIST

• Evaluate / Prioritize Bug Report
• Refine User Stories / Requirements
• Define Test Cases
• Design / Develop Solution
• Perform QA/Testing
• Update Documentation

[abitmore]

Fixed by #2609.