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.
593 lines
12 KiB
Go
593 lines
12 KiB
Go
// Copyright (c) 2026, Pim van Pelt <pim@ipng.ch>
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package config
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import (
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"testing"
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"time"
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)
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const validConfig = `
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maglev:
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healthchecker:
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transition-history: 5
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netns: dataplane
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vpp:
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lb:
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ipv4-src-address: 10.0.0.1
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ipv6-src-address: 2001:db8::1
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healthchecks:
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http-check:
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type: http
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port: 80
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probe-ipv4-src: 10.0.0.1
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params:
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path: /healthz
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host: example.com
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response-code: "200"
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interval: 2s
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timeout: 3s
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rise: 2
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fall: 3
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icmp-check:
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type: icmp
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probe-ipv6-src: 2001:db8:1::1
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interval: 1s
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timeout: 3s
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fall: 5
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backends:
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be-v4:
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address: 192.0.2.10
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healthcheck: http-check
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be-v6a:
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address: 2001:db8:2::1
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healthcheck: icmp-check
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be-v6b:
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address: 2001:db8:2::2
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healthcheck: icmp-check
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enabled: true
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frontends:
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web4:
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description: "IPv4 VIP"
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address: 192.0.2.1
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protocol: tcp
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port: 80
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pools:
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- name: primary
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backends:
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be-v4: {}
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web6:
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description: "IPv6 VIP"
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address: 2001:db8::1
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protocol: tcp
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port: 443
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pools:
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- name: primary
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backends:
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be-v6a:
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weight: 100
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be-v6b:
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weight: 50
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`
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func TestValidConfig(t *testing.T) {
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cfg, err := parse([]byte(validConfig))
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if err != nil {
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t.Fatalf("unexpected error: %v", err)
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}
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if cfg.HealthChecker.Netns != "dataplane" {
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t.Errorf("healthchecker.netns: got %q, want dataplane", cfg.HealthChecker.Netns)
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}
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if cfg.HealthChecker.TransitionHistory != 5 {
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t.Errorf("transition-history: got %d, want 5", cfg.HealthChecker.TransitionHistory)
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}
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if len(cfg.Frontends) != 2 {
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t.Fatalf("frontends: got %d, want 2", len(cfg.Frontends))
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}
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hc := cfg.HealthChecks["http-check"]
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if hc.Type != "http" {
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t.Errorf("http-check type: got %q, want http", hc.Type)
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}
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if hc.Fall != 3 || hc.Rise != 2 {
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t.Errorf("http-check fall/rise: got %d/%d, want 3/2", hc.Fall, hc.Rise)
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}
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if hc.ProbeIPv4Src.String() != "10.0.0.1" {
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t.Errorf("http-check probe-ipv4-src: got %s, want 10.0.0.1", hc.ProbeIPv4Src)
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}
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if hc.HTTP == nil {
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t.Fatal("http-check HTTP params should not be nil")
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}
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if hc.HTTP.Path != "/healthz" {
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t.Errorf("http-check path: got %q, want /healthz", hc.HTTP.Path)
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}
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if hc.HTTP.Host != "example.com" {
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t.Errorf("http-check host: got %q, want example.com", hc.HTTP.Host)
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}
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if hc.HTTP.ResponseCodeMin != 200 || hc.HTTP.ResponseCodeMax != 200 {
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t.Errorf("http-check response-code: got %d-%d, want 200-200",
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hc.HTTP.ResponseCodeMin, hc.HTTP.ResponseCodeMax)
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}
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icmp := cfg.HealthChecks["icmp-check"]
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if icmp.Fall != 5 {
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t.Errorf("icmp-check fall: got %d, want 5", icmp.Fall)
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}
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if icmp.ProbeIPv6Src.String() != "2001:db8:1::1" {
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t.Errorf("icmp-check probe-ipv6-src: got %s, want 2001:db8:1::1", icmp.ProbeIPv6Src)
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}
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// Backend fields.
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beV4 := cfg.Backends["be-v4"]
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if beV4.Address.String() != "192.0.2.10" {
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t.Errorf("be-v4 address: got %s", beV4.Address)
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}
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if beV4.HealthCheck != "http-check" {
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t.Errorf("be-v4 healthcheck: got %q", beV4.HealthCheck)
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}
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if !beV4.Enabled {
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t.Error("be-v4 enabled: want true (default)")
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}
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// Pool structure.
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web4 := cfg.Frontends["web4"]
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if len(web4.Pools) != 1 || web4.Pools[0].Name != "primary" {
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t.Errorf("web4 pools: got %v", web4.Pools)
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}
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if _, ok := web4.Pools[0].Backends["be-v4"]; !ok {
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t.Error("web4 primary pool missing be-v4")
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}
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if web4.Pools[0].Backends["be-v4"].Weight != 100 {
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t.Errorf("web4 be-v4 weight: got %d, want 100 (default)", web4.Pools[0].Backends["be-v4"].Weight)
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}
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web6 := cfg.Frontends["web6"]
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if len(web6.Pools) != 1 || len(web6.Pools[0].Backends) != 2 {
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t.Errorf("web6 pools[0] backends: got %d, want 2", len(web6.Pools[0].Backends))
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}
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if web6.Pools[0].Backends["be-v6b"].Weight != 50 {
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t.Errorf("web6 be-v6b weight: got %d, want 50", web6.Pools[0].Backends["be-v6b"].Weight)
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}
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}
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func TestDefaults(t *testing.T) {
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raw := `
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maglev:
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vpp:
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lb:
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ipv4-src-address: 10.0.0.1
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ipv6-src-address: 2001:db8::1
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healthchecks:
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icmp:
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type: icmp
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interval: 1s
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timeout: 2s
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backends:
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be:
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address: 10.0.0.2
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healthcheck: icmp
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frontends:
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v:
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address: 192.0.2.1
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pools:
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- name: primary
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backends:
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be: {}
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`
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cfg, err := parse([]byte(raw))
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if err != nil {
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t.Fatalf("unexpected error: %v", err)
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}
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if cfg.HealthChecker.Netns != "" {
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t.Errorf("default netns: got %q, want empty", cfg.HealthChecker.Netns)
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}
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if cfg.HealthChecker.TransitionHistory != 5 {
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t.Errorf("default transition-history: got %d, want 5", cfg.HealthChecker.TransitionHistory)
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}
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hc := cfg.HealthChecks["icmp"]
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if hc.Rise != 2 || hc.Fall != 3 {
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t.Errorf("defaults rise/fall: got %d/%d, want 2/3", hc.Rise, hc.Fall)
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}
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be := cfg.Backends["be"]
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if !be.Enabled {
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t.Errorf("backend default enabled: got false, want true")
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}
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// Pool backend weight defaults to 100.
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v := cfg.Frontends["v"]
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if v.Pools[0].Backends["be"].Weight != 100 {
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t.Errorf("pool backend default weight: got %d, want 100", v.Pools[0].Backends["be"].Weight)
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}
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}
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func TestBackendNoHealthcheck(t *testing.T) {
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// A backend with no healthcheck reference is valid; probe is skipped.
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raw := `
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maglev:
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vpp:
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lb:
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ipv4-src-address: 10.0.0.1
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ipv6-src-address: 2001:db8::1
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healthchecks: {}
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backends:
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be:
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address: 10.0.0.2
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frontends:
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v:
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address: 192.0.2.1
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pools:
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- name: primary
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backends:
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be: {}
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`
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cfg, err := parse([]byte(raw))
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if err != nil {
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t.Fatalf("unexpected error: %v", err)
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}
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if cfg.Backends["be"].HealthCheck != "" {
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t.Error("expected empty healthcheck")
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}
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}
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func TestOptionalIntervals(t *testing.T) {
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raw := `
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maglev:
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vpp:
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lb:
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ipv4-src-address: 10.0.0.1
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ipv6-src-address: 2001:db8::1
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healthchecks:
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icmp:
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type: icmp
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interval: 2s
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fast-interval: 500ms
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down-interval: 30s
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timeout: 1s
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backends:
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be:
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address: 10.0.0.2
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healthcheck: icmp
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frontends:
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v:
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address: 192.0.2.1
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pools:
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- name: primary
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backends:
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be: {}
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`
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cfg, err := parse([]byte(raw))
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if err != nil {
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t.Fatalf("unexpected error: %v", err)
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}
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hc := cfg.HealthChecks["icmp"]
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if hc.Interval != 2*time.Second {
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t.Errorf("interval: got %v, want 2s", hc.Interval)
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}
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if hc.FastInterval != 500*time.Millisecond {
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t.Errorf("fast-interval: got %v, want 500ms", hc.FastInterval)
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}
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if hc.DownInterval != 30*time.Second {
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t.Errorf("down-interval: got %v, want 30s", hc.DownInterval)
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}
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}
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func TestValidationErrors(t *testing.T) {
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base := func(hcExtra, beExtra, feExtra string) string {
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return `
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maglev:
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vpp:
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lb:
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ipv4-src-address: 10.0.0.1
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ipv6-src-address: 2001:db8::1
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healthchecks:
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c:
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type: icmp
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interval: 1s
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timeout: 2s
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` + hcExtra + `
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backends:
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be:
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address: 10.0.0.2
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healthcheck: c
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` + beExtra + `
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frontends:
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v:
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address: 192.0.2.1
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pools:
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- name: primary
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backends:
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be: {}
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` + feExtra
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}
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tests := []struct {
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name string
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yaml string
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errSub string
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}{
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{
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name: "wrong family probe-ipv4-src",
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yaml: base(" probe-ipv4-src: 2001:db8::1\n", "", ""),
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errSub: "probe-ipv4-src",
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},
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{
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name: "mixed backend address families in pool",
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yaml: `
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maglev:
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vpp:
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lb:
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ipv4-src-address: 10.0.0.1
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ipv6-src-address: 2001:db8::1
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healthchecks:
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c:
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type: icmp
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interval: 1s
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timeout: 2s
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backends:
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v4: {address: 10.0.0.2, healthcheck: c}
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v6: {address: 2001:db8::1, healthcheck: c}
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frontends:
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v:
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address: 192.0.2.1
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pools:
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- name: primary
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backends:
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v4: {}
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v6: {}
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`,
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errSub: "address family",
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},
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{
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name: "port without protocol",
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yaml: base("", "", " port: 80\n"),
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errSub: "port requires protocol",
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},
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{
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name: "protocol without port",
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yaml: `
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maglev:
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healthchecks:
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c:
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type: icmp
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interval: 1s
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timeout: 2s
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backends:
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be: {address: 10.0.0.2, healthcheck: c}
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frontends:
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v:
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address: 192.0.2.1
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protocol: tcp
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pools:
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- name: primary
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backends:
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be: {}
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`,
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errSub: "requires port",
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},
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{
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name: "invalid healthcheck type",
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yaml: `
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maglev:
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healthchecks:
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c:
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type: dns
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interval: 1s
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timeout: 2s
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backends:
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be: {address: 10.0.0.2, healthcheck: c}
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frontends:
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v:
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address: 192.0.2.1
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pools:
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- name: primary
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backends:
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be: {}
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`,
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errSub: "type must be",
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},
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{
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name: "http missing path",
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yaml: `
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maglev:
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healthchecks:
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c:
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type: http
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port: 80
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interval: 1s
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timeout: 2s
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backends:
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be: {address: 10.0.0.2, healthcheck: c}
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frontends:
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v:
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address: 192.0.2.1
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pools:
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- name: primary
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backends:
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be: {}
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`,
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errSub: "params.path",
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},
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{
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name: "no error case",
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yaml: base("", "", ""),
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errSub: "",
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},
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{
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name: "undefined healthcheck reference",
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yaml: `
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maglev:
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healthchecks: {}
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backends:
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be: {address: 10.0.0.2, healthcheck: missing}
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frontends:
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v:
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address: 192.0.2.1
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pools:
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- name: primary
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backends:
|
|
be: {}
|
|
`,
|
|
errSub: "not defined",
|
|
},
|
|
{
|
|
name: "undefined backend reference in pool",
|
|
yaml: `
|
|
maglev:
|
|
healthchecks:
|
|
c:
|
|
type: icmp
|
|
interval: 1s
|
|
timeout: 2s
|
|
backends: {}
|
|
frontends:
|
|
v:
|
|
address: 192.0.2.1
|
|
pools:
|
|
- name: primary
|
|
backends:
|
|
missing: {}
|
|
`,
|
|
errSub: "not defined",
|
|
},
|
|
{
|
|
name: "pool weight out of range",
|
|
yaml: `
|
|
maglev:
|
|
healthchecks:
|
|
c:
|
|
type: icmp
|
|
interval: 1s
|
|
timeout: 2s
|
|
backends:
|
|
be: {address: 10.0.0.2, healthcheck: c}
|
|
frontends:
|
|
v:
|
|
address: 192.0.2.1
|
|
pools:
|
|
- name: primary
|
|
backends:
|
|
be:
|
|
weight: 150
|
|
`,
|
|
errSub: "out of range",
|
|
},
|
|
{
|
|
name: "fall zero becomes default",
|
|
yaml: base(" fall: 0\n", "", ""),
|
|
errSub: "",
|
|
},
|
|
{
|
|
name: "tcp missing port",
|
|
yaml: `
|
|
maglev:
|
|
healthchecks:
|
|
c:
|
|
type: tcp
|
|
interval: 1s
|
|
timeout: 2s
|
|
backends:
|
|
be: {address: 10.0.0.2, healthcheck: c}
|
|
frontends:
|
|
v:
|
|
address: 192.0.2.1
|
|
pools:
|
|
- name: primary
|
|
backends:
|
|
be: {}
|
|
`,
|
|
errSub: "requires port",
|
|
},
|
|
{
|
|
name: "http missing port",
|
|
yaml: `
|
|
maglev:
|
|
healthchecks:
|
|
c:
|
|
type: http
|
|
interval: 1s
|
|
timeout: 2s
|
|
params:
|
|
path: /
|
|
backends:
|
|
be: {address: 10.0.0.2, healthcheck: c}
|
|
frontends:
|
|
v:
|
|
address: 192.0.2.1
|
|
pools:
|
|
- name: primary
|
|
backends:
|
|
be: {}
|
|
`,
|
|
errSub: "requires port",
|
|
},
|
|
{
|
|
name: "empty pools",
|
|
yaml: `
|
|
maglev:
|
|
healthchecks:
|
|
c:
|
|
type: icmp
|
|
interval: 1s
|
|
timeout: 2s
|
|
backends:
|
|
be: {address: 10.0.0.2, healthcheck: c}
|
|
frontends:
|
|
v:
|
|
address: 192.0.2.1
|
|
pools: []
|
|
`,
|
|
errSub: "pools must not be empty",
|
|
},
|
|
{
|
|
name: "pool missing name",
|
|
yaml: `
|
|
maglev:
|
|
healthchecks:
|
|
c:
|
|
type: icmp
|
|
interval: 1s
|
|
timeout: 2s
|
|
backends:
|
|
be: {address: 10.0.0.2, healthcheck: c}
|
|
frontends:
|
|
v:
|
|
address: 192.0.2.1
|
|
pools:
|
|
- backends:
|
|
be: {}
|
|
`,
|
|
errSub: "name must not be empty",
|
|
},
|
|
}
|
|
|
|
for _, tt := range tests {
|
|
t.Run(tt.name, func(t *testing.T) {
|
|
_, err := parse([]byte(tt.yaml))
|
|
if tt.errSub == "" {
|
|
if err != nil {
|
|
t.Fatalf("expected no error, got: %v", err)
|
|
}
|
|
return
|
|
}
|
|
if err == nil {
|
|
t.Fatalf("expected error containing %q, got nil", tt.errSub)
|
|
}
|
|
if !contains(err.Error(), tt.errSub) {
|
|
t.Errorf("error %q does not contain %q", err.Error(), tt.errSub)
|
|
}
|
|
})
|
|
}
|
|
}
|
|
|
|
func contains(s, sub string) bool {
|
|
return len(s) >= len(sub) && (s == sub || len(sub) == 0 ||
|
|
func() bool {
|
|
for i := 0; i <= len(s)-len(sub); i++ {
|
|
if s[i:i+len(sub)] == sub {
|
|
return true
|
|
}
|
|
}
|
|
return false
|
|
}())
|
|
}
|