Files
five/hbrtl/pgserver/errmap.go
CharlesKWON d98f5e1767 feat(pgserver): PostgreSQL-wire MVP — psql can SELECT from FiveSql2
First end-to-end working version of the PostgreSQL-wire-compatible
TCP server frontend. A standard `psql` client now connects, runs
`SELECT * FROM employees`, and gets back a properly typed result
set rendered by psql with the right column alignment:

    ID |         NAME         |  SALARY
    ----+----------------------+----------
      1 | Alice                | 50000.00
      2 | Bob                  | 42000.50
      3 | Cho                  | 77500.00

This is the Phase 2 deliverable from the approved plan at
/Users/charleskwon/.claude/plans/compiled-launching-shore.md.
Builds on the session-state refactor in 93cf5c8 — each connection
gets its own TSqlSession on the PRG side via the new PG_NEW_SESSION
HB_FUNC, so concurrent psql clients won't share transaction logs
or plan caches.

Scope
-----

v1.0 MVP: Simple Query only, trust auth, no TLS yet. SELECT works
against the full FiveSql2 surface (CTEs, window functions, JOINs,
aggregates). DML + per-session transactions are Phase 3, extended
protocol is Phase 4, auth + TLS are Phases 5/6.

Architecture
------------

  psql/pgx/JDBC ──TCP:5432──▶ pgserver.Listener
                                  │ accept()
                                  ▼ go handleConn(net.Conn)
                             ┌─────────────────────────────┐
                             │ Session goroutine            │
                             │  1. SSLRequest peek          │
                             │  2. StartupMessage           │
                             │  3. AuthenticationOk (trust) │
                             │  4. ParameterStatus×7        │
                             │  5. BackendKeyData           │
                             │  6. ReadyForQuery('I')       │
                             │  7. loop: Receive() →        │
                             │     dispatchSimpleQuery →    │
                             │     hbrt.Thread.Function(    │
                             │       FIVE_SQL,sql,...,sess) │
                             │     emit RowDescription      │
                             │     emit DataRow×N           │
                             │     emit CommandComplete     │
                             │     emit ReadyForQuery       │
                             └─────────────────────────────┘

One goroutine per connection, each owning its own *hbrt.Thread and
TSqlSession instance. Uses the existing audit-fixed NewThread()
(cde8673) so statics + WA factory propagate.

New files (hbrtl/pgserver/)
---------------------------

* server.go — Config, Server, Serve loop with MaxConnections gate
  via semaphore, Close drains in-flight sessions.
* session.go — full lifecycle: SSLRequest peek + prefixedConn
  byte-injection trick for StartupMessage, ParameterStatus
  broadcast (server_version "14.0 (FiveSql2)" so pgx negotiates),
  BackendKeyData (random pid+secret per session, no CancelRequest
  yet), query loop dispatching only Simple Query in v1.0 with a
  loud "0A000 not supported" for Extended messages.
* dispatch.go — runSQL invokes FIVE_SQL via PushSymbol+Function,
  unpacks the engine's `{aFieldNames, aRows}` envelope or the
  `{{"__error__"}, {{nCode, cMsg, cSQL}}}` error shape, emits
  RowDescription with text-format OIDs and DataRow per row.
* typemap.go — pgTypeFor() picks INT4 / INT8 / NUMERIC / TEXT /
  DATE / TIMESTAMP / BOOL by sampling the first row's value type;
  encodeText() formats each cell, returning nil-slice for NULL
  (the PG length=-1 convention).
* errmap.go — sqlStateFor() maps FiveSql2 SQL_ERR_* codes to
  canonical PG SQLSTATEs (42601/42P01/42703/42804/23505/23514/
  23503/25P02/42501/02000/XX000).
* auth.go — trust mode in v1.0; password/MD5/SCRAM lands Phase 5
  but the dispatch sentinel is already in place.
* tls.go — upgradeToTLS stub for SSLRequest handling; the byte-
  ordering is already wired so Phase 6 just plugs in tls.Config.
* register.go — package init() registers pg_server_start /
  pg_server_stop HB_FUNCs. Importing the package (done from
  hbrtl/register.go via blank import) is enough to enable them.
* pgserver_test.go — unit tests for encodeText (numeric, string,
  NIL), pgTypeFor (OID dispatch), sqlStateFor (error mapping),
  commandTagFor (SELECT/INSERT/UPDATE/DELETE/BEGIN/COMMIT).

Other changes
-------------

* _FiveSql2/src/TSqlSession.prg — added PG_NEW_SESSION() factory
  used by the Go dispatcher to allocate a per-connection session
  bypassing the embedded process default.
* hbrtl/register.go — blank-import five/hbrtl/pgserver so its
  init() fires and the HB_FUNCs land in the global dynamic-func
  table for VM symbol lookup.
* go.mod / go.sum — github.com/jackc/pgx/v5 v5.9.2 (pgproto3
  subpackage). MIT license. Same library pgx itself uses, so
  protocol coverage matches the de-facto Go PG ecosystem.

Verification
------------

  $ pg_server_start(15432, "trust")     /* PRG one-liner */
  $ psql -h 127.0.0.1 -p 15432 -U fiveuser -c 'SELECT * FROM employees'
  → 3 rows rendered correctly by psql (ID as INT4, NAME as TEXT,
    SALARY as NUMERIC(10,2) with 2 decimal places)

All six release gates green:
  go test ./...               ✓ (incl. new hbrtl/pgserver tests)
  FiveSql2 SQL:1999 43/43     ✓
  Harbour compat 56/56        ✓
  std.ch 17/17                ✓
  FRB 7/7                     ✓
  examples 65/71              ✓ (unchanged baseline)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-16 18:40:32 +09:00

69 lines
2.0 KiB
Go

// Copyright (c) 2026 Charles KWON OhJun (charleskwonohjun@gmail.com)
// All rights reserved.
package pgserver
import "github.com/jackc/pgx/v5/pgproto3"
// sqlStateFor maps a FiveSql2 error code (from FiveSqlDef.ch
// SQL_ERR_*) to a PostgreSQL SQLSTATE 5-char identifier so
// clients can dispatch error handlers in their native idiom.
//
// Codes that don't have a clean PG equivalent fall back to XX000
// (internal_error) — the universal "something went wrong" bucket.
func sqlStateFor(code int) string {
// FiveSqlDef.ch numeric mapping (kept in sync with the .ch file):
// 1 SQL_ERR_SYNTAX → 42601 syntax_error
// 2 SQL_ERR_TABLE → 42P01 undefined_table
// 3 SQL_ERR_COLUMN → 42703 undefined_column
// 4 SQL_ERR_TYPE → 42804 datatype_mismatch
// 5 SQL_ERR_UNIQUE → 23505 unique_violation
// 6 SQL_ERR_CHECK → 23514 check_violation
// 7 SQL_ERR_FK → 23503 foreign_key_violation
// 8 SQL_ERR_TXN → 25P02 in_failed_sql_transaction
// 9 SQL_ERR_PERM → 42501 insufficient_privilege
// 10 SQL_ERR_NOTFOUND → 02000 no_data
switch code {
case 1:
return "42601"
case 2:
return "42P01"
case 3:
return "42703"
case 4:
return "42804"
case 5:
return "23505"
case 6:
return "23514"
case 7:
return "23503"
case 8:
return "25P02"
case 9:
return "42501"
case 10:
return "02000"
default:
return "XX000"
}
}
// buildErrorResponse assembles a pgproto3.ErrorResponse from the
// triplet FiveSql2 surfaces. Optional Query field carries the
// offending SQL so error-aware clients (pgAdmin, DataGrip) can
// highlight the source.
func buildErrorResponse(sqlState, message, query string) *pgproto3.ErrorResponse {
resp := &pgproto3.ErrorResponse{
Severity: "ERROR",
Code: sqlState,
Message: message,
}
if query != "" {
// PG's "InternalQuery" field surfaces in psql with a
// "QUERY:" line directly under the error message.
resp.InternalQuery = query
}
return resp
}