Files
vpp-maglev/cmd/maglevc/tree_test.go
Pim van Pelt d3c5c86037 VPP load-balancer dataplane integration: state, sync, and global conf
This commit wires maglevd through to VPP's LB plugin end-to-end, using
locally-generated GoVPP bindings for the newer v2 API messages.

VPP binapi (vendored)
- New package internal/vpp/binapi/ containing lb, lb_types, ip_types, and
  interface_types, generated from a local VPP build (~/src/vpp) via a new
  'make vpp-binapi' target. GoVPP v0.12.0 upstream lacks the v2 messages we
  need (lb_conf_get, lb_add_del_vip_v2, lb_add_del_as_v2, lb_as_v2_dump,
  lb_as_set_weight), so we commit the generated output in-tree.
- All generated files go through our loggedChannel wrapper; every VPP API
  send/receive is recorded at DEBUG via slog (vpp-api-send / vpp-api-recv /
  vpp-api-send-multi / vpp-api-recv-multi) so the full wire-level trail is
  auditable. NewAPIChannel is unexported — callers must use c.apiChannel().

Read path: GetLBState{All,VIP}
- GetLBStateAll returns a full snapshot (global conf + every VIP with its
  attached application servers).
- GetLBStateVIP looks up a single VIP by (prefix, protocol, port) and
  returns (nil, nil) when the VIP doesn't exist in VPP. This is the
  efficient path for targeted updates on a busy LB.
- Helpers factored out: getLBConf, dumpAllVIPs, dumpASesForVIP, lookupVIP,
  vipFromDetails.

Write path: SyncLBState{All,VIP}
- SyncLBStateAll reconciles every configured frontend with VPP: creates
  missing VIPs, removes stale ones (with AS flush), and reconciles AS
  membership and weights within VIPs that exist on both sides.
- SyncLBStateVIP targets a single frontend by name. Never removes VIPs.
  Returns ErrFrontendNotFound (wrapped with the name) when the frontend
  isn't in config, so callers can use errors.Is.
- Shared reconcileVIP helper does the per-VIP AS diff; removeVIP is used
  only by the full-sync pass.
- LbAddDelVipV2 requests always set NewFlowsTableLength=1024. The .api
  default=1024 annotation is only applied by VAT/CLI parsers, not wire-
  level marshalling — sending 0 caused VPP to vec_validate with mask
  0xFFFFFFFF and OOM-panic.
- Pool semantics: backends in the primary (first) pool of a frontend get
  their configured weight; backends in secondary pools get weight 0. All
  backends are installed so higher layers can flip weights on failover
  without add/remove churn.
- Every individual change emits a DEBUG slog (vpp-lbsync-vip-add/del,
  vpp-lbsync-as-add/del, vpp-lbsync-as-weight). Start/done INFO logs
  carry a scope=all|vip label plus aggregate counts.

Global conf push: SetLBConf
- New SetLBConf(cfg) sends lb_conf with ipv4-src, ipv6-src, sticky-buckets,
  and flow-timeout. Called automatically on VPP (re)connect and after
  every config reload (via doReloadConfig). Results are cached on the
  Client so redundant pushes are silently skipped — only actual changes
  produce a vpp-lb-conf-set INFO log line.

Periodic drift reconciliation
- vpp.Client.lbSyncLoop runs in a goroutine tied to each VPP connection's
  lifetime. Its first tick is immediate (startup and post-reconnect
  sync quickly); subsequent ticks fire every vpp.lb.sync-interval from
  config (default 30s). Purpose: catch drift if something/someone
  modifies VPP state by hand. The loop uses a ConfigSource interface
  (satisfied by checker.Checker via its new Config() accessor) to avoid
  an import cycle with the checker package.

Config schema additions (maglev.vpp.lb)
- sync-interval: positive Go duration, default 30s.
- ipv4-src-address: REQUIRED. Used as the outer source for GRE4 encap
  to application servers. Missing this is a hard semantic error —
  maglevd --check exits 2 and the daemon refuses to start. VPP GRE
  needs a source address and every VIP we program uses GRE, so there
  is no meaningful config without it.
- ipv6-src-address: REQUIRED. Same treatment as ipv4-src-address.
- sticky-buckets-per-core: default 65536, must be a power of 2.
- flow-timeout: default 40s, must be a whole number of seconds in [1s, 120s].
- VPP validation runs at the end of convert() so structural errors in
  healthchecks/backends/frontends surface first — operators fix those,
  then get the VPP-specific requirements.

gRPC API
- New GetVPPLBState RPC returning VPPLBState: global conf + VIPs with
  ASes. Mirrors the read-path but strips fields irrelevant to our
  GRE-only deployment (srv_type, dscp, target_port).
- New SyncVPPLBState RPC with optional frontend_name. Unset → full sync
  (may remove stale VIPs). Set → single-VIP sync (never removes).
  Returns codes.NotFound for unknown frontends, codes.Unavailable when
  VPP integration is disabled or disconnected.

maglevc (CLI)
- New 'show vpp lbstate' command displaying the LB plugin state. VPP-only
  fields the dataplane irrelevant to GRE are suppressed. Per-AS lines use
  a key-value format ("address X  weight Y  flow-table-buckets Z")
  instead of a tabwriter column, which avoids the ANSI-color alignment
  issue we hit with mixed label/data rows.
- New 'sync vpp lbstate [<name>]' command. Without a name, triggers a
  full reconciliation; with a name, targets one frontend.
- Previous 'show vpp lb' renamed to 'show vpp lbstate' for consistency
  with the new sync command.

Test fixtures
- validConfig and all ad-hoc config_test.go fixtures that reach the end
  of convert() now include the two required vpp.lb src addresses.
- tests/01-maglevd/maglevd-lab/maglev.yaml gains a vpp.lb section so the
  robot integration tests can still load the config.
- cmd/maglevc/tree_test.go gains expected paths for the new commands.

Docs
- config-guide.md: new 'vpp' section in the basic structure, detailed
  vpp.lb field reference, noting ipv4/ipv6 src addresses as REQUIRED
  (hard error) with no defaults; example config updated.
- user-guide.md: documented 'show vpp info', 'show vpp lbstate',
  'sync vpp lbstate [<name>]', new --vpp-api-addr and --vpp-stats-addr
  flags, the vpp-lb-conf-set log line, and corrected the pause/resume
  description to reflect that pause cancels the probe goroutine.
- debian/maglev.yaml: example config gains a vpp.lb block with src
  addresses and commented optional overrides.
2026-04-12 10:58:44 +02:00

158 lines
4.4 KiB
Go

// Copyright (c) 2026, Pim van Pelt <pim@ipng.ch>
package main
import (
"strings"
"testing"
)
func TestExpandPathsRoot(t *testing.T) {
root := buildTree()
lines := expandPaths(root, "", make(map[*Node]bool))
// Should include well-known leaf paths.
want := []string{
"show version",
"show frontends",
"show frontends <name>",
"show backends",
"show backends <name>",
"show healthchecks",
"show healthchecks <name>",
"set backend <name> pause",
"set backend <name> resume",
"set backend <name> disable",
"set backend <name> enable",
"set frontend <name> pool <pool> backend <backend> weight <weight>",
"watch events",
"watch events <opt>",
"config check",
"show vpp info",
"show vpp lbstate",
"config reload",
"sync vpp lbstate",
"sync vpp lbstate <name>",
"quit",
"exit",
}
paths := make(map[string]bool, len(lines))
for _, l := range lines {
paths[l.path] = true
}
for _, w := range want {
if !paths[w] {
t.Errorf("expandPaths(root) missing %q", w)
}
}
}
func TestExpandPathsShow(t *testing.T) {
root := buildTree()
showNode, _ := Walk(root, []string{"show"})
lines := expandPaths(showNode, "show", make(map[*Node]bool))
for _, l := range lines {
if !strings.HasPrefix(l.path, "show ") {
t.Errorf("unexpected path %q: should start with 'show '", l.path)
}
if l.help == "" {
t.Errorf("path %q has empty help", l.path)
}
}
// version, frontends, frontends <name>, backends, backends <name>,
// healthchecks, healthchecks <name>, vpp info, vpp lb = 9 lines
if len(lines) != 9 {
t.Errorf("expected exactly 9 show subcommands, got %d", len(lines))
}
}
func TestExpandPathsNoCycles(t *testing.T) {
root := buildTree()
// watch events has a self-referencing slot; expandPaths must terminate.
watchEvents, _ := Walk(root, []string{"watch", "events"})
lines := expandPaths(watchEvents, "watch events", make(map[*Node]bool))
// Should produce exactly 2 lines: "watch events" and "watch events <opt>".
if len(lines) != 2 {
t.Errorf("watch events: expected 2 lines, got %d: %v", len(lines), lines)
}
}
func TestExpandPathsSetBackendName(t *testing.T) {
root := buildTree()
// Walk to the name slot so displayPrefix carries the actual arg.
node, _ := Walk(root, []string{"set", "backend", "mybackend"})
lines := expandPaths(node, "set backend mybackend", make(map[*Node]bool))
want := []string{
"set backend mybackend pause",
"set backend mybackend resume",
"set backend mybackend disable",
"set backend mybackend enable",
}
if len(lines) != len(want) {
t.Fatalf("expected %d lines, got %d: %v", len(want), len(lines), lines)
}
for i, w := range want {
if lines[i].path != w {
t.Errorf("line %d: got %q, want %q", i, lines[i].path, w)
}
}
}
func TestPrefixMatchCollapsedNouns(t *testing.T) {
root := buildTree()
// "sh ba" → show backends (list all) via prefix matching.
node, args := Walk(root, []string{"sh", "ba"})
if node.Run == nil {
t.Fatal("'sh ba' did not reach a Run node")
}
if len(args) != 0 {
t.Errorf("'sh ba' should have 0 args, got %v", args)
}
// "sh ba nginx0" → show backends <name> (get specific) via slot.
node, args = Walk(root, []string{"sh", "ba", "nginx0"})
if node.Run == nil {
t.Fatal("'sh ba nginx0' did not reach a Run node")
}
if len(args) != 1 || args[0] != "nginx0" {
t.Errorf("'sh ba nginx0' args: got %v, want [nginx0]", args)
}
// "sh fr" → show frontends (list all).
node, _ = Walk(root, []string{"sh", "fr"})
if node.Run == nil {
t.Fatal("'sh fr' did not reach a Run node")
}
// "sh he icmp" → show healthchecks icmp (get specific).
node, args = Walk(root, []string{"sh", "he", "icmp"})
if node.Run == nil {
t.Fatal("'sh he icmp' did not reach a Run node")
}
if len(args) != 1 || args[0] != "icmp" {
t.Errorf("'sh he icmp' args: got %v, want [icmp]", args)
}
}
func TestExpandPathsWeightSlotWalk(t *testing.T) {
// Verify the weight command is fully walkable (fixes bug: setWeightValue
// and setFrontendPoolName were non-slot nodes that couldn't capture tokens).
root := buildTree()
node, args := Walk(root, []string{"set", "frontend", "web", "pool", "primary", "backend", "be0", "weight", "42"})
if node.Run == nil {
t.Fatal("Walk did not reach a Run node for full weight command")
}
if len(args) != 4 {
t.Errorf("expected 4 args (name, pool, backend, weight), got %d: %v", len(args), args)
}
if args[3] != "42" {
t.Errorf("args[3] (weight): got %q, want 42", args[3])
}
}