Rewrite AGENTS.md sentence by sentence

Rewrite the agent rules from scratch, with one idea per sentence and
every file name and command in backticks. Drop the rule that models
embed `models.Base`, which no package has. Say that the linter keeps
tests in external test packages, and that an `export_test.go` file
gives them access to unexported code. Limit the rules on doc comments
and blank imports to files outside the tests. State magic numbers as
a preference, and correct the blank-line rule for `return`. State the
branch workflow: pull requests target `next` and only the owner
merges `next` into `main`. Record the three snake_case JSON tags the
HTTP API keeps.

Part of #190.

Model: fable-5-1 (writing, rework); opus-5-5 (rework)

Dockerfile

@@ -33,18 +33,14 @@ RUN golangci-lint run --config .golangci.yml ./...
 # golang:1.24.13-bookworm, 2026-10-06
 FROM golang@sha256:1a6d4452c65dea36aac2e2d606b01b4a029ec90cc1ae53890540ce6173ea77ac AS test
 WORKDIR /src
+COPY go.mod go.sum ./
+RUN go mod download
 COPY . .
 RUN mkdir -p web/dist && touch web/dist/index.html web/dist/style.css web/dist/app.js
 # -p 4 because test runs on a shared build host cap their parallelism.
-# The modules download in this RUN rather than a layer of their own, because
-# exporting a layer that holds them is slow. Nothing reads them or the build
-# cache afterwards, so go clean removes both.
-RUN set -e; \
-    go mod download; \
-    go test -p 4 -timeout 90s -race -cover ./... || \
+RUN go test -p 4 -timeout 90s -race -cover ./... || \
     { echo "--- Rerunning with -v for details ---"; \
-      go test -p 4 -timeout 90s -race -v ./...; exit 1; }; \
-    go clean -cache -modcache
+      go test -p 4 -timeout 90s -race -v ./...; exit 1; }
 
 # Build stage. Nothing is wanted from either phase above; the copies
 # are what make BuildKit build them first, so this stage cannot run

internal/db/auth.go

@@ -10,6 +10,13 @@ import (
 	"golang.org/x/crypto/bcrypt"
 )
 
+//nolint:gochecknoglobals // var so tests can override via SetBcryptCost
+var bcryptCost = bcrypt.DefaultCost
+
+// SetBcryptCost overrides the bcrypt cost.
+// Use bcrypt.MinCost in tests to avoid slow hashing.
+func SetBcryptCost(cost int) { bcryptCost = cost }
+
 var errNoPassword = errors.New(
 	"account has no password set",
 )
@@ -22,7 +29,7 @@ func (database *Database) SetPassword(
 	password string,
 ) error {
 	hash, err := bcrypt.GenerateFromPassword(
-		[]byte(password), bcrypt.DefaultCost,
+		[]byte(password), bcryptCost,
 	)
 	if err != nil {
 		return fmt.Errorf("hash password: %w", err)

internal/db/db.go

@@ -85,6 +85,11 @@ func New(
 	return database, nil
 }
 
+// GetDB returns the underlying sql.DB connection.
+func (database *Database) GetDB() *sql.DB {
+	return database.conn
+}
+
 func (database *Database) connect(ctx context.Context) error {
 	dbURL := database.params.Config.DBURL
 	if dbURL == "" {

internal/db/export_test.go

@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"log/slog"
 	"testing"
-	"time"
 
 	"sneak.berlin/go/neoirc/internal/dbtest"
 )
@@ -68,78 +67,3 @@ func (database *Database) ExecForTest(
 
 	return nil
 }
-
-// GetDB returns the underlying sql.DB connection.
-func (database *Database) GetDB() *sql.DB {
-	return database.conn
-}
-
-// GetOrCreateChannel returns channel id, creating if needed.
-// Uses INSERT OR IGNORE to avoid TOCTOU races.
-func (database *Database) GetOrCreateChannel(
-	ctx context.Context,
-	name string,
-) (int64, error) {
-	now := time.Now()
-
-	_, err := database.conn.ExecContext(ctx,
-		`INSERT OR IGNORE INTO channels
-		 (name, created_at, updated_at)
-		 VALUES (?, ?, ?)`,
-		name, now, now)
-	if err != nil {
-		return 0, fmt.Errorf("create channel: %w", err)
-	}
-
-	var channelID int64
-
-	err = database.conn.QueryRowContext(
-		ctx,
-		"SELECT id FROM channels WHERE name = ?",
-		name,
-	).Scan(&channelID)
-	if err != nil {
-		return 0, fmt.Errorf("get channel: %w", err)
-	}
-
-	return channelID, nil
-}
-
-// JoinChannel adds a session to a channel.
-func (database *Database) JoinChannel(
-	ctx context.Context,
-	channelID, sessionID int64,
-) error {
-	_, err := database.conn.ExecContext(ctx,
-		`INSERT OR IGNORE INTO channel_members
-		 (channel_id, session_id, joined_at)
-		 VALUES (?, ?, ?)`,
-		channelID, sessionID, time.Now())
-	if err != nil {
-		return fmt.Errorf("join channel: %w", err)
-	}
-
-	return nil
-}
-
-// HasChannelInvite checks if a session has been invited
-// to a channel.
-func (database *Database) HasChannelInvite(
-	ctx context.Context,
-	channelID, sessionID int64,
-) (bool, error) {
-	var count int
-
-	err := database.conn.QueryRowContext(ctx,
-		`SELECT COUNT(*) FROM channel_invites
-		 WHERE channel_id = ? AND session_id = ?`,
-		channelID, sessionID,
-	).Scan(&count)
-	if err != nil {
-		return false, fmt.Errorf(
-			"check invite: %w", err,
-		)
-	}
-
-	return count > 0, nil
-}

internal/db/main_test.go

@@ -0,0 +1,14 @@
+package db_test
+
+import (
+	"os"
+	"testing"
+
+	"golang.org/x/crypto/bcrypt"
+	"sneak.berlin/go/neoirc/internal/db"
+)
+
+func TestMain(m *testing.M) {
+	db.SetBcryptCost(bcrypt.MinCost)
+	os.Exit(m.Run())
+}

internal/db/queries.go

@@ -320,6 +320,29 @@ type ClientHostInfo struct {
 	Hostname string
 }
 
+// GetClientHostInfo returns the IP and hostname for a
+// client.
+func (database *Database) GetClientHostInfo(
+	ctx context.Context,
+	clientID int64,
+) (*ClientHostInfo, error) {
+	var info ClientHostInfo
+
+	err := database.conn.QueryRowContext(
+		ctx,
+		`SELECT ip, hostname
+		 FROM clients WHERE id = ?`,
+		clientID,
+	).Scan(&info.IP, &info.Hostname)
+	if err != nil {
+		return nil, fmt.Errorf(
+			"get client host info: %w", err,
+		)
+	}
+
+	return &info, nil
+}
+
 // SetSessionOper sets the is_oper flag on a session.
 func (database *Database) SetSessionOper(
 	ctx context.Context,
@@ -410,6 +433,54 @@ func (database *Database) GetChannelByName(
 	return channelID, nil
 }
 
+// GetOrCreateChannel returns channel id, creating if needed.
+// Uses INSERT OR IGNORE to avoid TOCTOU races.
+func (database *Database) GetOrCreateChannel(
+	ctx context.Context,
+	name string,
+) (int64, error) {
+	now := time.Now()
+
+	_, err := database.conn.ExecContext(ctx,
+		`INSERT OR IGNORE INTO channels
+		 (name, created_at, updated_at)
+		 VALUES (?, ?, ?)`,
+		name, now, now)
+	if err != nil {
+		return 0, fmt.Errorf("create channel: %w", err)
+	}
+
+	var channelID int64
+
+	err = database.conn.QueryRowContext(
+		ctx,
+		"SELECT id FROM channels WHERE name = ?",
+		name,
+	).Scan(&channelID)
+	if err != nil {
+		return 0, fmt.Errorf("get channel: %w", err)
+	}
+
+	return channelID, nil
+}
+
+// JoinChannel adds a session to a channel.
+func (database *Database) JoinChannel(
+	ctx context.Context,
+	channelID, sessionID int64,
+) error {
+	_, err := database.conn.ExecContext(ctx,
+		`INSERT OR IGNORE INTO channel_members
+		 (channel_id, session_id, joined_at)
+		 VALUES (?, ?, ?)`,
+		channelID, sessionID, time.Now())
+	if err != nil {
+		return fmt.Errorf("join channel: %w", err)
+	}
+
+	return nil
+}
+
 // Errors that CreateOrJoinChannel refuses a join with.
 var (
 	ErrBannedFromChannel = errors.New("banned from channel")
@@ -1056,6 +1127,23 @@ func (database *Database) GetChannelMemberIDs(
 	return scanInt64s(rows)
 }
 
+// GetSessionChannelIDs returns channel IDs for a session.
+func (database *Database) GetSessionChannelIDs(
+	ctx context.Context,
+	sessionID int64,
+) ([]int64, error) {
+	rows, err := database.conn.QueryContext(ctx,
+		`SELECT channel_id FROM channel_members
+		 WHERE session_id = ?`, sessionID)
+	if err != nil {
+		return nil, fmt.Errorf(
+			"get session channel ids: %w", err,
+		)
+	}
+
+	return scanInt64s(rows)
+}
+
 // InsertMessage stores a message and returns its DB ID.
 // toSessionID is the session a DM or INVITE is sent to and
 // toChannelID the channel a channel message is sent to;
@@ -2372,6 +2460,28 @@ func (database *Database) AddChannelInvite(
 	return nil
 }
 
+// HasChannelInvite checks if a session has been invited
+// to a channel.
+func (database *Database) HasChannelInvite(
+	ctx context.Context,
+	channelID, sessionID int64,
+) (bool, error) {
+	var count int
+
+	err := database.conn.QueryRowContext(ctx,
+		`SELECT COUNT(*) FROM channel_invites
+		 WHERE channel_id = ? AND session_id = ?`,
+		channelID, sessionID,
+	).Scan(&count)
+	if err != nil {
+		return false, fmt.Errorf(
+			"check invite: %w", err,
+		)
+	}
+
+	return count > 0, nil
+}
+
 // --- Tier 2: Secret (+s) ---
 
 // IsChannelSecret checks if a channel has +s mode.

internal/db/queries_test.go

@@ -125,7 +125,7 @@ func TestCreateSessionStoresIP(t *testing.T) {
 	database := setupTestDB(t)
 	ctx := t.Context()
 
-	sessionID, _, _, err := database.CreateSession(
+	sessionID, clientID, _, err := database.CreateSession(
 		ctx, "ipuser", "ident", "host.example.com",
 		"192.168.1.42",
 	)
@@ -147,8 +147,8 @@ func TestCreateSessionStoresIP(t *testing.T) {
 		)
 	}
 
-	clientInfo, err := database.GetLatestClientForSession(
-		ctx, sessionID,
+	clientInfo, err := database.GetClientHostInfo(
+		ctx, clientID,
 	)
 	if err != nil {
 		t.Fatal(err)
@@ -169,6 +169,19 @@ func TestCreateSessionStoresIP(t *testing.T) {
 	}
 }
 
+func TestGetClientHostInfoNotFound(t *testing.T) {
+	t.Parallel()
+
+	database := setupTestDB(t)
+
+	_, err := database.GetClientHostInfo(
+		t.Context(), 99999,
+	)
+	if err == nil {
+		t.Fatal("expected error for nonexistent client")
+	}
+}
+
 func TestGetSessionHostInfoNotFound(t *testing.T) {
 	t.Parallel()
 

internal/db/testing.go

@@ -0,0 +1,25 @@
+package db
+
+import (
+	"context"
+	"database/sql"
+	"log/slog"
+)
+
+// NewTestDatabaseFromConn creates a Database wrapping an
+// existing *sql.DB connection.  Intended for integration
+// tests in other packages.
+func NewTestDatabaseFromConn(conn *sql.DB) *Database {
+	return &Database{ //nolint:exhaustruct
+		conn: conn,
+		log:  slog.Default(),
+	}
+}
+
+// RunMigrations applies all schema migrations.  Exposed
+// for integration tests in other packages.
+func (database *Database) RunMigrations(
+	ctx context.Context,
+) error {
+	return database.runMigrations(ctx)
+}

internal/dbtest/dbtest.go

@@ -1,5 +1,5 @@
-// Package dbtest gives each test a database of its own and runs raw
-// SQL on it. Only tests may import it.
+// Package dbtest gives each test a database of its own. Only tests
+// may import it.
 package dbtest
 
 import (
@@ -37,23 +37,3 @@ func NewURL(tb testing.TB) string {
 
 	return dbURL
 }
-
-// Exec runs one raw SQL statement on the database at dbURL, over a
-// connection of its own. A test uses it for what the methods of
-// db.Database cannot do, such as creating a trigger that makes a
-// write fail.
-func Exec(tb testing.TB, dbURL, statement string) {
-	tb.Helper()
-
-	pool, err := sql.Open("sqlite", dbURL)
-	if err != nil {
-		tb.Fatalf("open test database: %v", err)
-	}
-
-	defer func() { _ = pool.Close() }()
-
-	_, err = pool.ExecContext(tb.Context(), statement)
-	if err != nil {
-		tb.Fatalf("run %q: %v", statement, err)
-	}
-}

internal/handlers/api.go

@@ -188,7 +188,7 @@ func (hdlr *Handlers) handleCreateSession(
 
 	var payload createRequest
 
-	err := decodeJSON(request, &payload)
+	err := json.NewDecoder(request.Body).Decode(&payload)
 	if err != nil {
 		hdlr.respondError(
 			writer, request,
@@ -925,7 +925,7 @@ func (hdlr *Handlers) HandleSendCommand() http.HandlerFunc {
 
 		var payload commandRequest
 
-		err := decodeJSON(request, &payload)
+		err := json.NewDecoder(request.Body).Decode(&payload)
 		if err != nil {
 			hdlr.respondError(
 				writer, request,
@@ -3238,7 +3238,7 @@ func (hdlr *Handlers) handleWho(
 		// 315 RPL_ENDOFWHO (empty result)
 		hdlr.enqueueNumeric(
 			ctx, clientID, irc.RplEndOfWho, nick,
-			[]string{channel},
+			[]string{target},
 			"End of /WHO list",
 		)
 		hdlr.broker.Notify(sessionID)

internal/handlers/api_test.go

@@ -47,25 +47,22 @@ import (
 const templateDBURL = "file:template?mode=memory&cache=shared"
 
 func TestMain(m *testing.M) {
-	template := fx.New(
-		fx.NopLogger,
-		fx.Supply(
-			&globals.Globals{},
-			&config.Config{DBURL: templateDBURL},
-		),
-		fx.Provide(logger.New, newTestDB),
-		// fx makes the database only if something asks for it.
-		fx.Invoke(func(*db.Database) {}),
-	)
+	db.SetBcryptCost(bcrypt.MinCost)
 
-	err := template.Start(context.Background())
+	template, err := sql.Open("sqlite", templateDBURL)
+	if err != nil {
+		panic(err)
+	}
+
+	err = db.NewTestDatabaseFromConn(template).
+		RunMigrations(context.Background())
 	if err != nil {
 		panic(err)
 	}
 
 	code := m.Run()
 
-	_ = template.Stop(context.Background())
+	_ = template.Close()
 
 	os.Exit(code)
 }
@@ -140,7 +137,6 @@ type testServer struct {
 	t          *testing.T
 	fxApp      *fxtest.App
 	broker     *broker.Broker
-	dbURL      string
 	database   *db.Database
 	handlers   *handlers.Handlers
 }
@@ -235,7 +231,6 @@ func newTestServerWith(
 		t:          t,
 		fxApp:      app,
 		broker:     brk,
-		dbURL:      dbURL,
 		database:   database,
 		handlers:   hdlr,
 	}
@@ -802,104 +797,6 @@ func TestCreateSessionMalformed(t *testing.T) {
 	}
 }
 
-func (tserver *testServer) postBody(
-	path, token, body string,
-) (int, map[string]any) {
-	tserver.t.Helper()
-
-	resp, err := doRequestAuth(
-		tserver.t, http.MethodPost, tserver.url(path), token,
-		strings.NewReader(body),
-	)
-	if err != nil {
-		tserver.t.Fatalf("post %s: %v", path, err)
-	}
-
-	defer func() { _ = resp.Body.Close() }()
-
-	var result map[string]any
-
-	_ = json.NewDecoder(resp.Body).Decode(&result)
-
-	return resp.StatusCode, result
-}
-
-// TestRequestBodyLimit sends each endpoint a small valid JSON value
-// followed by other bytes. Only whitespace may follow the value, and
-// the whole body counts towards MAX_MESSAGE_SIZE.
-func TestRequestBodyLimit(t *testing.T) {
-	t.Parallel()
-
-	const (
-		maxMessageSize = 4096 // the default MAX_MESSAGE_SIZE
-		nick           = "alice_bodylimit"
-	)
-
-	endpoints := []struct {
-		name, path, value string
-		acceptedStatus    int
-	}{
-		{
-			"create session", apiSession,
-			`{"nick":"bob_bodylimit"}`,
-			http.StatusCreated,
-		},
-		{
-			"login", "/api/v1/login",
-			`{"nick":"` + nick + `","password":"` + testPassword + `"}`,
-			http.StatusOK,
-		},
-		{
-			"post message", apiMessages,
-			`{"command":"PING"}`,
-			http.StatusOK,
-		},
-	}
-
-	for _, endpoint := range endpoints {
-		t.Run(endpoint.name, func(t *testing.T) {
-			t.Parallel()
-
-			tserver := newTestServer(t)
-			token := tserver.createSession(nick)
-
-			tserver.setPassword(nick)
-
-			bytesToLimit := maxMessageSize - len(endpoint.value)
-
-			for _, trailing := range []string{
-				strings.Repeat(" ", bytesToLimit+1),
-				strings.Repeat("x", bytesToLimit+1),
-				"x",
-				"{}",
-			} {
-				status, result := tserver.postBody(
-					endpoint.path, token, endpoint.value+trailing,
-				)
-				if status != http.StatusBadRequest ||
-					result["error"] != "invalid request body" {
-					t.Errorf(
-						"%d bytes of %.10q after the value: expected "+
-							"400 invalid request body, got %d: %v",
-						len(trailing), trailing, status, result,
-					)
-				}
-			}
-
-			status, result := tserver.postBody(
-				endpoint.path, token,
-				endpoint.value+strings.Repeat(" ", bytesToLimit),
-			)
-			if status != endpoint.acceptedStatus {
-				t.Errorf(
-					"body of exactly the limit: expected %d, got %d: %v",
-					endpoint.acceptedStatus, status, result,
-				)
-			}
-		})
-	}
-}
-
 func TestAuthNoCookie(t *testing.T) {
 	t.Parallel()
 
@@ -1765,7 +1662,9 @@ func checkQuitRace(
 		firstToken := tserver.createSession(nick)
 		observerToken := tserver.createSession("raceobserver")
 
-		tserver.setPassword(nick)
+		tserver.sendCommand(firstToken, map[string]any{
+			commandKey: irc.CmdPass, bodyKey: []string{testPassword},
+		})
 
 		tokens := []string{firstToken, tserver.login(nick)}
 
@@ -1815,7 +1714,9 @@ func TestLogoutOfOneClientKeepsSession(t *testing.T) {
 	firstToken := tserver.createSession(nick)
 	observerToken := tserver.createSession("logoutobserver")
 
-	tserver.setPassword(nick)
+	tserver.sendCommand(firstToken, map[string]any{
+		commandKey: irc.CmdPass, bodyKey: []string{testPassword},
+	})
 
 	secondToken := tserver.login(nick)
 
@@ -1885,12 +1786,15 @@ func TestFailedLogoutChangesNothing(t *testing.T) {
 
 	_, lastID := tserver.pollMessages(observerToken, 0)
 
-	dbtest.Exec(t, tserver.dbURL,
+	_, err := tserver.database.GetDB().ExecContext(t.Context(),
 		`CREATE TRIGGER keep_sessions
 		 BEFORE DELETE ON sessions
 		 BEGIN
 		   SELECT RAISE(ABORT, 'sessions are kept');
 		 END`)
+	if err != nil {
+		t.Fatal(err)
+	}
 
 	resp, err := doRequestAuth(
 		t, http.MethodPost, tserver.url(apiLogout), token, nil,
@@ -2124,24 +2028,6 @@ func (tserver *testServer) longPoll(
 	return result.Messages, nil
 }
 
-// setPassword gives the session nick the password testPassword
-// without sending PASS. It hashes at bcrypt.MinCost, and a login
-// compares at the cost stored in the hash, so both are fast.
-func (tserver *testServer) setPassword(nick string) {
-	tserver.t.Helper()
-
-	hash, err := bcrypt.GenerateFromPassword(
-		[]byte(testPassword), bcrypt.MinCost,
-	)
-	if err != nil {
-		tserver.t.Fatalf("hash password: %v", err)
-	}
-
-	dbtest.Exec(tserver.t, tserver.dbURL,
-		"UPDATE sessions SET password_hash = '"+string(hash)+
-			"' WHERE nick = '"+nick+"'")
-}
-
 // login logs in to the session nick with testPassword and
 // returns the new client's token.
 func (tserver *testServer) login(nick string) string {
@@ -3749,8 +3635,13 @@ func TestLoginValid(t *testing.T) {
 
 	tserver := newTestServer(t)
 
-	tserver.createSession("loginuser")
-	tserver.setPassword("loginuser")
+	// Create session and set password via PASS command.
+	token := tserver.createSession("loginuser")
+
+	tserver.sendCommand(token, map[string]any{
+		commandKey: irc.CmdPass,
+		bodyKey:    []string{testPassword},
+	})
 
 	// Login with nick + password.
 	loginBody, err := json.Marshal(map[string]string{
@@ -3814,8 +3705,13 @@ func TestLoginWrongPassword(t *testing.T) {
 
 	tserver := newTestServer(t)
 
-	tserver.createSession("wrongpwuser")
-	tserver.setPassword("wrongpwuser")
+	// Create session and set password via PASS command.
+	token := tserver.createSession("wrongpwuser")
+
+	tserver.sendCommand(token, map[string]any{
+		commandKey: irc.CmdPass,
+		bodyKey:    []string{"correctpass1"},
+	})
 
 	postJSONExpectStatus(
 		t, tserver, "/api/v1/login",
@@ -4143,31 +4039,6 @@ func assertWhoReplyUsername(
 	)
 }
 
-func TestWhoUnknownChannelEndReplyAddsHash(t *testing.T) {
-	t.Parallel()
-
-	tserver := newTestServer(t)
-
-	token := tserver.createSession("whoasker")
-
-	_, lastID := tserver.pollMessages(token, 0)
-
-	msgs, _ := sendAndPoll(tserver, token, lastID, map[string]any{
-		commandKey: irc.CmdWho,
-		toKey:      "nosuch",
-	})
-
-	endOfWho := findNumericWithParams(msgs, "315")
-	if endOfWho == nil {
-		t.Fatalf("expected RPL_ENDOFWHO (315), got %v", msgs)
-	}
-
-	params := getNumericParams(endOfWho)
-	if !slices.Equal(params, []string{"#nosuch"}) {
-		t.Fatalf("expected params [#nosuch], got %v", params)
-	}
-}
-
 func TestSessionUsernameDefault(t *testing.T) {
 	t.Parallel()
 
@@ -4286,8 +4157,13 @@ func TestLoginRateLimitAllowsNormalUse(t *testing.T) {
 
 	tserver := newTestServer(t)
 
-	tserver.createSession("normaluser")
-	tserver.setPassword("normaluser")
+	// Create session and set password via PASS command.
+	token := tserver.createSession("normaluser")
+
+	tserver.sendCommand(token, map[string]any{
+		commandKey: irc.CmdPass,
+		bodyKey:    []string{testPassword},
+	})
 
 	// A single login should succeed without rate limiting.
 	loginBody, err := json.Marshal(map[string]string{

internal/handlers/auth.go

@@ -1,6 +1,7 @@
 package handlers
 
 import (
+	"encoding/json"
 	"net/http"
 	"strings"
 
@@ -54,7 +55,7 @@ func (hdlr *Handlers) handleLogin(
 
 	var payload loginRequest
 
-	err := decodeJSON(request, &payload)
+	err := json.NewDecoder(request.Body).Decode(&payload)
 	if err != nil {
 		hdlr.respondError(
 			writer, request,

internal/handlers/handlers.go

@@ -5,7 +5,6 @@ import (
 	"context"
 	"encoding/json"
 	"errors"
-	"io"
 	"log/slog"
 	"net/http"
 	"time"
@@ -160,18 +159,6 @@ func (hdlr *Handlers) respondError(
 	)
 }
 
-// decodeJSON reads the whole request body and decodes it into dest.
-// It fails if the body is larger than the http.MaxBytesReader limit,
-// or holds anything other than one JSON value and whitespace.
-func decodeJSON(request *http.Request, dest any) error {
-	body, err := io.ReadAll(request.Body)
-	if err != nil {
-		return err
-	}
-
-	return json.Unmarshal(body, dest)
-}
-
 func (hdlr *Handlers) idleTimeout() time.Duration {
 	raw := hdlr.params.Config.SessionIdleTimeout
 	if raw == "" {

internal/ircserver/relay_test.go

@@ -8,8 +8,6 @@ import (
 	"testing"
 	"time"
 
-	"golang.org/x/crypto/bcrypt"
-	"sneak.berlin/go/neoirc/internal/dbtest"
 	"sneak.berlin/go/neoirc/internal/ircserver"
 	"sneak.berlin/go/neoirc/internal/service"
 )
@@ -585,10 +583,8 @@ func ownSessionCopies(
 
 // aliceWithHTTPClient connects alice to the IRC listener and
 // has her join #chan, which bob is on too, then adds an HTTP API
-// client to her session with a password, as POST /api/v1/login
-// does. It stores that password without sending PASS. It hashes
-// at bcrypt.MinCost, and a login compares at the cost stored in
-// the hash, so both are fast. It returns her connection, bob's
+// client to her session with the password her connection set,
+// as POST /api/v1/login does. It returns her connection, bob's
 // connection, her session and her HTTP API client.
 func aliceWithHTTPClient(
 	t *testing.T, env *testEnv,
@@ -598,24 +594,15 @@ func aliceWithHTTPClient(
 	const password = "alicepass"
 
 	alice := env.dial(t)
+	alice.send("PASS " + password)
 	alice.register("alice")
+	// Registration stores the password before the JOIN runs.
 	alice.joinAndDrain("#chan")
 
 	bob := env.dial(t)
 	bob.register("bob")
 	bob.joinAndDrain("#chan")
 
-	hash, err := bcrypt.GenerateFromPassword(
-		[]byte(password), bcrypt.MinCost,
-	)
-	if err != nil {
-		t.Fatalf("hash password: %v", err)
-	}
-
-	dbtest.Exec(t, env.dbURL,
-		"UPDATE sessions SET password_hash = '"+string(hash)+
-			"' WHERE nick = 'alice'")
-
 	sessionID, httpClientID, _, err := env.database.LoginUser(
 		t.Context(), "alice", password, "127.0.0.1", "localhost",
 	)

internal/ircserver/server_test.go

@@ -32,9 +32,14 @@ import (
 
 const testTimeout = 5 * time.Second
 
+func TestMain(m *testing.M) {
+	db.SetBcryptCost(4)
+
+	os.Exit(m.Run())
+}
+
 // testEnv holds the shared test infrastructure.
 type testEnv struct {
-	dbURL    string
 	database *db.Database
 	brk      *broker.Broker
 	cfg      *config.Config
@@ -105,26 +110,33 @@ func newTestEnvWithResolver(
 ) *testEnv {
 	t.Helper()
 
-	dbURL := dbtest.NewURL(t)
-	lifecycle := fxtest.NewLifecycle(t)
-
-	dbLog, err := logger.New(lifecycle, logger.Params{
-		Globals: &globals.Globals{},
-	})
+	conn, err := sql.Open("sqlite", dbtest.NewURL(t))
 	if err != nil {
-		t.Fatalf("new logger: %v", err)
+		t.Fatalf("open db: %v", err)
 	}
 
-	database, err := db.New(lifecycle, db.Params{
-		Logger: dbLog,
-		Config: &config.Config{DBURL: dbURL},
+	t.Cleanup(func() {
+		err := conn.Close()
+		if err != nil {
+			t.Logf("close db: %v", err)
+		}
 	})
+
+	conn.SetMaxOpenConns(1)
+
+	_, err = conn.ExecContext(
+		t.Context(), "PRAGMA foreign_keys = ON",
+	)
 	if err != nil {
-		t.Fatalf("new database: %v", err)
+		t.Fatalf("pragma: %v", err)
 	}
 
-	lifecycle.RequireStart()
-	t.Cleanup(lifecycle.RequireStop)
+	database := db.NewTestDatabaseFromConn(conn)
+
+	err = database.RunMigrations(t.Context())
+	if err != nil {
+		t.Fatalf("migrate: %v", err)
+	}
 
 	brk := broker.New()
 
@@ -149,7 +161,6 @@ func newTestEnvWithResolver(
 	t.Cleanup(srv.Stop)
 
 	return &testEnv{
-		dbURL:    dbURL,
 		database: database,
 		brk:      brk,
 		cfg:      cfg,
@@ -918,7 +929,12 @@ func quitSeenByPeers(t *testing.T, quit string) (string, []string) {
 		t.Fatalf("create peer session: %v", err)
 	}
 
-	_, _, err = env.database.CreateOrJoinChannel(ctx, "#bye", apiPeerID, "")
+	channelID, err := env.database.GetChannelByName(ctx, "#bye")
+	if err != nil {
+		t.Fatalf("get channel: %v", err)
+	}
+
+	err = env.database.JoinChannel(ctx, channelID, apiPeerID)
 	if err != nil {
 		t.Fatalf("join peer: %v", err)
 	}
@@ -989,9 +1005,12 @@ func TestStopEndsSessions(t *testing.T) {
 		t.Fatalf("create peer session: %v", err)
 	}
 
-	channelID, _, err := env.database.CreateOrJoinChannel(
-		ctx, "#shut", peerID, "",
-	)
+	channelID, err := env.database.GetChannelByName(ctx, "#shut")
+	if err != nil {
+		t.Fatalf("get channel: %v", err)
+	}
+
+	err = env.database.JoinChannel(ctx, channelID, peerID)
 	if err != nil {
 		t.Fatalf("join peer: %v", err)
 	}
@@ -1049,16 +1068,11 @@ func TestStopReturnsWhileCleanupIsStuck(t *testing.T) {
 
 	client.register("stuck")
 
-	// While a connection of the test's own holds a write
-	// transaction, the cleanup's first write waits for it to end.
-	holder, err := sql.Open("sqlite", env.dbURL)
+	// The test database has one connection. While the test
+	// holds it, the cleanup's first query waits for it.
+	held, err := env.database.GetDB().Conn(t.Context())
 	if err != nil {
-		t.Fatalf("open a second database connection: %v", err)
-	}
-
-	_, err = holder.ExecContext(t.Context(), "BEGIN IMMEDIATE")
-	if err != nil {
-		t.Fatalf("begin a write transaction: %v", err)
+		t.Fatalf("take the database connection: %v", err)
 	}
 
 	stopped := make(chan struct{})
@@ -1074,11 +1088,10 @@ func TestStopReturnsWhileCleanupIsStuck(t *testing.T) {
 		t.Error("Stop did not return while a cleanup was stuck")
 	}
 
-	// Closing ends the transaction, which lets the cleanup finish
-	// before the database is closed.
-	err = holder.Close()
+	// Lets the cleanup finish before the database is closed.
+	err = held.Close()
 	if err != nil {
-		t.Errorf("close the second database connection: %v", err)
+		t.Errorf("release the database connection: %v", err)
 	}
 }
 
@@ -1357,11 +1370,14 @@ func TestPassPostRegistrationNotStored(t *testing.T) {
 
 	client.register("failpass")
 
-	dbtest.Exec(t, env.dbURL,
+	_, err := env.database.GetDB().ExecContext(t.Context(),
 		`CREATE TRIGGER refuse_password
 		 BEFORE UPDATE OF password_hash ON sessions
 		 BEGIN SELECT RAISE(ABORT, 'refused'); END`,
 	)
+	if err != nil {
+		t.Fatalf("create trigger: %v", err)
+	}
 
 	client.send("PASS :mypassword123")
 

internal/service/service_test.go

@@ -9,6 +9,7 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
+	"os"
 	"slices"
 	"strings"
 	"sync"
@@ -17,6 +18,7 @@ import (
 
 	"go.uber.org/fx"
 	"go.uber.org/fx/fxtest"
+	"golang.org/x/crypto/bcrypt"
 	"sneak.berlin/go/neoirc/internal/broker"
 	"sneak.berlin/go/neoirc/internal/config"
 	"sneak.berlin/go/neoirc/internal/db"
@@ -28,10 +30,14 @@ import (
 	"sneak.berlin/go/neoirc/pkg/irc"
 )
 
+func TestMain(m *testing.M) {
+	db.SetBcryptCost(bcrypt.MinCost)
+	os.Exit(m.Run())
+}
+
 // testEnv holds all dependencies for a service test.
 type testEnv struct {
 	svc    *service.Service
-	dbURL  string
 	db     *db.Database
 	broker *broker.Broker
 	app    *fxtest.App
@@ -105,7 +111,6 @@ func newTestEnv(t *testing.T) *testEnv {
 
 	return &testEnv{
 		svc:    svc,
-		dbURL:  dbURL,
 		db:     database,
 		broker: brk,
 		app:    app,
@@ -935,16 +940,19 @@ func TestSendDirectMessageTargetQuits(t *testing.T) {
 	sid := createSession(ctx, t, env.db, "alice")
 	createSession(ctx, t, env.db, "bob")
 
-	dbtest.Exec(t, env.dbURL,
+	_, err := env.db.GetDB().ExecContext(ctx,
 		`CREATE TRIGGER delete_recipient
 		 BEFORE INSERT ON messages
 		 BEGIN
 		   DELETE FROM sessions WHERE id = NEW.to_session_id;
 		 END`)
+	if err != nil {
+		t.Fatalf("create trigger: %v", err)
+	}
 
 	body, _ := json.Marshal([]string{"hi"}) //nolint:errchkjson
 
-	_, err := env.svc.SendDirectMessage(
+	_, err = env.svc.SendDirectMessage(
 		ctx, sid, 0, "alice", irc.CmdPrivmsg, "bob", body, nil,
 	)
 
@@ -970,12 +978,15 @@ func TestSendChannelMessageChannelDeleted(t *testing.T) {
 		t.Fatalf("join alice: %v", err)
 	}
 
-	dbtest.Exec(t, env.dbURL,
+	_, err = env.db.GetDB().ExecContext(ctx,
 		`CREATE TRIGGER delete_recipient
 		 BEFORE INSERT ON messages
 		 BEGIN
 		   DELETE FROM channels WHERE id = NEW.to_channel_id;
 		 END`)
+	if err != nil {
+		t.Fatalf("create trigger: %v", err)
+	}
 
 	body, _ := json.Marshal([]string{"hi"}) //nolint:errchkjson