Add missing acronyms (OS, ARN, VM ...) to cmd/osgen's initialism table (#1047)

* Add missing acronyms (OS, ARN, CFS, DN, IAM, IO, JDK, LLM, MAC, MHz, PID, RRF, SSO, VM, SES, SNS, SQS) to cmd/osgen's initialism table

NodesInfoNode.Os renders as Os instead of OS because the acronym
table cmd/osgen/naming.go derives Go field names from didn't list
it, unlike the existing API/HTTP/JSON entries. Auditing every
generated JSON tag segment for the same gap surfaced 14 more:
ARN, CFS, DN, IAM, IO, JDK, LLM, MAC, MHz, PID, RRF, SSO, TTF,
VM and SES, SNS, SQS.

Add all 15 to the table and regenerate; the diff is confined to the
fields that use these segments (e.g. VmName -> VMName, SsoLogoutURL ->
SSOLogoutURL, RoleArn -> RoleARN).


Signed-off-by: Ryan Yuan <ryan.yuan@crowdstrike.com>
Signed-off-by: Sean Chittenden <sean.chittenden@crowdstrike.com>
Co-authored-by: Sean Chittenden <sean.chittenden@crowdstrike.com>

Author: ryanyuan

CHANGELOG.md

@@ -200,6 +200,7 @@ Inspired from [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 - **BREAKING**: Partial-failure errors are now reported by default. `Config.Errors == nil` resolves to `errmask.Empty` (report every partial-failure category) instead of v4's `errmask.All` (mask everything). Set `Errors: errmask.New(errmask.All)` or `OPENSEARCH_GO_ERROR_MASK` to restore v4-style masking ([#816](https://github.com/opensearch-project/opensearch-go/issues/816))
 - **BREAKING**: `cmd/osgen` now treats the OpenSearch plugin acronyms `ISM`, `KNN`, `LTR`, `ML`, `PPL`, `SM`, `UBI`, and `WLM` as initialisms, so generated identifiers are all-uppercase per Go convention (matching the existing `API`, `HTTP`, `JSON`, etc. handling). Renames every affected `*_gen.go` type, path builder, and method, e.g. `IsmPolicy` -> `ISMPolicy`, `KnnStats` -> `KNNStats`, `SmPolicy` -> `SMPolicy`. Update any direct references to the renamed identifiers; the lowercase plugin package names (`ism`, `knn`, ...) are unchanged ([#863](https://github.com/opensearch-project/opensearch-go/issues/863))
 - `cmd/osgen` recognizes more acronyms as initialisms, extending the set from [#863](https://github.com/opensearch-project/opensearch-go/issues/863). Adds `BM25`, `CJK`, `CSV`, `DFI`, `DFR`, `FS`, `GC`, `HDR`, `HTML`, `IB`, `ICU`, `IDs`, `JVM`, `LMD`, `LMJ`, `MMap`, `NIO`, `PITs`, `SMTP`, `SNS`, `TFIDF`, `UAX`, `WKT`, and `XY` to the generator's acronym table, so generated identifiers use idiomatic Go capitalization (e.g. `IndicesIndexSettingsSimilarityBM25`, `CommonAnalysisCJKAnalyzer`, `CommonQueryDSLIDsQuery`, `GetAllPITsReq`, `NodesStatsLastGC`, `ClusterStatsClusterJVM`). Plural acronyms keep a lowercase `s` (`IDs`, `PITs`) per Go convention; the memory-map and NIO store types follow `MMap`/`NIO`. JSON wire tags are unchanged ([#961](https://github.com/opensearch-project/opensearch-go/issues/961))
+- **BREAKING**: `cmd/osgen` now treats `ARN`, `CFS`, `DN`, `IAM`, `IO`, `JDK`, `LLM`, `MAC`, `MHz`, `OS`, `PID`, `RRF`, `SES`, `SSO`, `TTF`, and `VM` as initialisms, extending the acronym table from [#961](https://github.com/opensearch-project/opensearch-go/issues/961) (matching the existing `API`/`HTTP`/`JSON` handling). Renames every affected `*_gen.go` field across `opensearchapi` and the plugin packages, e.g. `NodesInfoNode.Os` -> `OS`, `NodesStatsStats.IoStats` -> `IOStats`, `ClusterStatsClusterNodes.VmName` -> `VMName`, `NodesInfoNode.Pid` -> `PID`, `NodesInfoNode.MacAddress` -> `MACAddress`, `AuthinfoResp.SsoLogoutURL` -> `SSOLogoutURL`, `WhoAmIResp.Dn` -> `DN`, `MLRegisterAgentsBody.Llm` -> `LLM`, `IamRoleArn` -> `IAMRoleARN`, `TopicArn`/`CampaignArn` -> `TopicARN`/`CampaignARN`, `CombRrfExecutions`/`CombRrfProcessors` -> `CombRRFExecutions`/`CombRRFProcessors`, `SumTtf` -> `SumTTF`, `NotificationsSesAccount` -> `NotificationsSESAccount` (with the `GetConfigsParams.SesAccount*` query parameters following as `SESAccount*`), and `CfsPeriodMicros`/`CfsQuotaMicros`/`NoCfsRatio` -> `CFSPeriodMicros`/`CFSQuotaMicros`/`NoCFSRatio`. JSON wire tags are unchanged
 - `cmd/osgen` derives clearer names for `oneOf`/`anyOf` union branches. Aggregation-result branches that the spec titles with terse codes split into readable Go names (`Lterms` -> `LTerms`, `Tdigest` -> `TDigest`, and the full long/string/unsigned/unmapped/significant family), so the `As*`/`New*From*` methods on types like `SearchResultAggregationsValue` read as `AsLTerms`/`AsTDigestPercentiles`. Inline-object branches carry their spec `title` where one exists (a hyphenated title normalizes to PascalCase, `score-ranker-processor` -> `ScoreRankerProcessor`); untitled members are named from their content instead of their spec-array position, so a branch is named for its first required field or, when it declares none, for its property names (`IndicesOpenRespBodyObject0`/`Object1` -> `...Task`/`...Acknowledged`, `WLMQueryGroupRespResourceLimitsObject0`/`Object1` -> `...Memory`/`...CPU`, `SearchBodySourceObject1` -> `...ExcludesIncludes`). The name no longer shifts when the spec reorders a union's members. Two branches with identical fields that cannot be told apart keep a positional `ObjectN` name. Branch accessors and constructors no longer repeat the union prefix, so `NewInsightsSourceSourceFromInsightsSourceSourceObject1` becomes `NewInsightsSourceSourceFromExcludesIncludes` ([#961](https://github.com/opensearch-project/opensearch-go/issues/961))
 - **BREAKING**: `opensearchtransport.ConnectionObserver` interface gained an `OnAddressRewrite(AddressRewriteEvent)` method for the new address resolver feature (embedders of `BaseConnectionObserver` are unaffected) ([#822](https://github.com/opensearch-project/opensearch-go/pull/822))
 - **BREAKING**: Rename `opensearchtransport.Client` to `opensearchtransport.Transport` so the type name reflects its role (HTTP round-trip concerns: connection pool, retries, node selection, discovery) rather than colliding conceptually with `opensearch.Client` and `opensearchapi.Client`. The `Client` name is removed; update references to `Transport` ([#853](https://github.com/opensearch-project/opensearch-go/issues/853))

cmd/osgen/naming.go

@@ -157,53 +157,69 @@ func replaceAtPascalBoundary(s, old, next string, tailUpperOnly bool) string {
 //nolint:gochecknoglobals // const-ish read-only lookup table
 var acronyms = map[string]string{
 	"api":    "API",
+	"arn":    "ARN",  // Amazon Resource Name
 	"bm25":   "BM25", // Best Matching 25 ranking function
+	"cfs":    "CFS",  // Completely Fair Scheduler (cgroup)
 	"cjk":    "CJK",  // Chinese, Japanese, Korean
 	"cpu":    "CPU",
 	"csv":    "CSV",
 	"dfi":    "DFI", // Divergence From Independence
 	"dfr":    "DFR", // Divergence From Randomness
 	"dfs":    "DFS", // Distributed Frequency Search
+	"dn":     "DN",  // Distinguished Name (LDAP)
 	"dsl":    "DSL",
 	"fs":     "FS",  // File System (store type)
 	"gc":     "GC",  // Garbage Collection
 	"hdr":    "HDR", // High Dynamic Range (percentiles)
 	"html":   "HTML",
 	"http":   "HTTP",
 	"https":  "HTTPS",
+	"iam":    "IAM", // Identity and Access Management
 	"ib":     "IB",  // Information-Based similarity
 	"icu":    "ICU", // International Components for Unicode
 	"id":     "ID",
 	"ids":    "IDs",
+	"io":     "IO", // Input/Output
 	"ip":     "IP",
 	"ip2geo": "IP2Geo", // IP-to-geolocation datasource (geospatial plugin)
 	"ism":    "ISM",    // Index State Management
+	"jdk":    "JDK",    // Java Development Kit
 	"json":   "JSON",
 	"jvm":    "JVM",
 	"knn":    "KNN",  // k-Nearest Neighbors
+	"llm":    "LLM",  // Large Language Model
 	"lmd":    "LMD",  // Language Model Dirichlet similarity
 	"lmj":    "LMJ",  // Language Model Jelinek-Mercer similarity
 	"ltr":    "LTR",  // Learning to Rank
+	"mac":    "MAC",  // Media Access Control (address)
+	"mhz":    "MHz",  // Megahertz
 	"ml":     "ML",   // Machine Learning
 	"mmap":   "MMap", // memory-mapped store type
 	"nio":    "NIO",  // New I/O (Java, store type)
+	"os":     "OS",   // Operating System
+	"pid":    "PID",  // Process ID
 	"pit":    "PIT",  // Point In Time
 	"pits":   "PITs",
 	"ppl":    "PPL", // Piped Processing Language
+	"rrf":    "RRF", // Reciprocal Rank Fusion
+	"ses":    "SES", // Simple Email Service
 	"sm":     "SM",  // Snapshot Management
 	"smtp":   "SMTP",
 	"sns":    "SNS", // Simple Notification Service
 	"sql":    "SQL",
 	"ssl":    "SSL",
+	"sso":    "SSO", // Single Sign-On
 	"tcp":    "TCP",
 	"tfidf":  "TFIDF", // Term Frequency-Inverse Document Frequency
 	"tls":    "TLS",
+	"ttf":    "TTF", // Total Term Frequency
 	"ttl":    "TTL",
 	"uax":    "UAX", // Unicode Annex (UAX #29 text segmentation)
 	"ubi":    "UBI", // User Behavior Insights
 	"uri":    "URI",
 	"url":    "URL",
 	"uuid":   "UUID",
+	"vm":     "VM",  // Virtual Machine
 	"wkt":    "WKT", // Well-Known Text (geometry format)
 	"wlm":    "WLM", // Workload Management
 	"xml":    "XML",