lawless-m Elasticsearch (5.2, fixed)
The cluster runs Elasticsearch 5.2 and will not change. Use ES 5.2 API shapes: _type still exists in bulk metadata, hits.total is a plain int, and modern client libraries won't work. We do not use NEST — ServiceLib.Elasticsearch is a plain HttpClient wrapper over the REST API.
Working code in this folder: Elasticsearch.cs (the ServiceLib wrapper) and ElasticsearchService.cs (JordanPrice's use of it, including the full alias rebuild). Method-level detail: reference-wrapper.md.
Production cluster
https://rocs-production-es.ramsden-international.com (no port, no auth needed for reads). Query it directly with curl for ad-hoc lookups.
Live aliases → concrete index (as of 2026-08-11 — re-check with _cat/aliases, the timestamped targets move on every rebuild):
| alias | concrete index |
|---|---|
customers |
customers_20260515093004 |
order_lines |
order_lines_20260811100001 |
order_lines_view |
order_lines_add |
price_discount |
price_discount_20260810231502 |
products |
products_20260811073038 |
profiles |
profiles_20260811083002 |
Non-aliased indices in use: orders, quotes, metrics, ingredients, saved_items, shipments, pricing_periods, templates, sequence, last_synchronisation.
Note the plurals — the customer index is customers, not customer. Single-doc lookup by code:
curl -s 'https://rocs-production-es.ramsden-international.com/customers/_search' \
-H 'Content-Type: application/json' \
-d '{"query":{"ids":{"values":["BPC-100531"]}}}'
Customer/BP codes are the _id, so an ids query works and — unlike a GET by id — is safe against an alias (see de-aliasing below).
Conventions
- Search results are parsed as
dynamic(Newtonsoft) and navigated by property name:result.hits.hits[0]._source, null-safe with?.and?.ToString() ?? "". No typed models. - Complex queries are raw string literals (
$$"""...""") with interpolated values. - Wrapper methods return the string
"Error"on failure rather than throwing — callers must check for it. - Indices are created without explicit mappings — let ES auto-detect field types (matches production).
- Scroll downloads (
DownloadIndex): 5000-doc batches, 1m timeout, and the scroll context is always cleared in a finally block — leaked scroll contexts hold resources on this old cluster.
Index rebuild: timestamped index + alias (JordanPrice-proven)
Zero-downtime full rebuild, proven in JordanPrice:
- Create timestamped index, e.g.
price_discount_20250116_123456 - Bulk-load all documents into it
- Atomically switch alias
price_discountin one_aliasescall (removeprice_discount_*+ add new index) - On failure, delete the new index; rollback is just switching the alias back
Architectural direction: the legacy Java codebase writes whole timestamped indices and flips aliases as above. RI's stated direction for new work is in-place overwrites and deletes instead of full rebuilds — prefer that for new services, but the alias pattern remains the proven fallback for full reloads.
De-aliasing for document operations
ES 5.2 misroutes single-document operations addressed to an alias. The wrapper's DeAliasURL/ConcreteIndex resolve an alias to its concrete index first and build URLs as /{concrete_index}/{alias}/{id}. Any direct document PUT/DELETE against a name that might be an alias must go through this (see reference-wrapper.md).
Bulk format nulls (BulkToJson)
BulkToJson builds the NDJSON body with an asymmetry that matters: action metadata lines are serialized keeping nulls, document lines ignoring nulls. Keep that split when touching bulk code — dropping nulls from metadata or including them in documents both cause subtle diffs against the legacy Java output.