consul/command/connect/envoy/bootstrap_config.go

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package envoy
import (
"bytes"
"fmt"
"net"
"net/url"
"os"
"strings"
"text/template"
)
// BootstrapConfig is the set of keys we care about in a Connect.Proxy.Config
// map. Note that this only includes config keys that affects Envoy bootstrap
// generation. For Envoy config keys that affect runtime xDS behavior see
// agent/xds/config.go.
type BootstrapConfig struct {
// StatsdURL allows simple configuration of the statsd metrics sink. If
// tagging is required, use DogstatsdURL instead. The URL must be in one of
// the following forms:
// - udp://<ip>:<port>
// - $ENV_VAR_NAME in this case the ENV var named will have it's
// value taken and is expected to contain a URL in
// one of the supported forms above.
StatsdURL string `mapstructure:"envoy_statsd_url"`
// DogstatsdURL allows simple configuration of the dogstatsd metrics sink
// which allows tags and Unix domain sockets. The URL must be in one of the
// following forms:
// - udp://<ip>:<port>
// - unix:///full/path/to/unix.sock
// - $ENV_VAR_NAME in this case the ENV var named will have it's
// value taken and is expected to contain a URL in
// one of the supported forms above.
DogstatsdURL string `mapstructure:"envoy_dogstatsd_url"`
// StatsTags is a slice of string values that will be added as tags to
// metrics. They are used to configure
// https://www.envoyproxy.io/docs/envoy/v1.9.0/api-v2/config/metrics/v2/stats.proto#envoy-api-msg-config-metrics-v2-statsconfig
// and add to the basic tags Consul adds by default like the local_cluster
// name. Only exact values are supported here. Full configuration of
// stats_config.stats_tags can be made by overriding envoy_stats_config_json.
StatsTags []string `mapstructure:"envoy_stats_tags"`
// PrometheusBindAddr configures an <ip>:<port> on which the Envoy will listen
// and expose a single /metrics HTTP endpoint for Prometheus to scrape. It
// does this by proxying that URL to the internal admin server's prometheus
// endpoint which allows exposing metrics on the network without the security
// risk of exposing the full admin server API. Any other URL requested will be
// a 404.
//
// Note that as of Envoy 1.9.0, the built in Prometheus endpoint only exports
// counters and gauges but not timing information via histograms. This is
// fixed in 1.10-dev currently in Envoy master. Other changes since 1.9.0 make
// master incompatible with the current release of Consul Connect. This will
// be fixed in a future Consul version as Envoy 1.10 reaches stable release.
PrometheusBindAddr string `mapstructure:"envoy_prometheus_bind_addr"`
// OverrideJSONTpl allows replacing the base template used to render the
// bootstrap. This is an "escape hatch" allowing arbitrary control over the
// proxy's configuration but will the most effort to maintain and correctly
// configure the aspects that Connect relies upon to work. It's recommended
// that this only be used if necessary, and that it be based on the default
// template in
// https://github.com/hashicorp/consul/blob/master/command/connect/envoy/bootstrap_tpl.go
// for the correct version of Consul and Envoy being used.
OverrideJSONTpl string `mapstructure:"envoy_bootstrap_json_tpl"`
// StaticClustersJSON is a JSON string containing zero or more Cluster
// definitions. They are appended to the "static_resources.clusters" list. A
// single cluster should be given as a plain object, if more than one is to be
// added, they should be separated by a comma suitable for direct injection
// into a JSON array.
//
// Note that cluster names should be chosen in such a way that they won't
// collide with service names since we use plain service names as cluster
// names in xDS to make metrics population simpler and cluster names mush be
// unique.
//
// This is mostly intended for providing clusters for tracing or metrics
// services.
//
// See https://www.envoyproxy.io/docs/envoy/v1.9.0/api-v2/api/v2/cds.proto.
StaticClustersJSON string `mapstructure:"envoy_extra_static_clusters_json"`
// StaticListenersJSON is a JSON string containing zero or more Listener
// definitions. They are appended to the "static_resources.listeners" list. A
// single listener should be given as a plain object, if more than one is to
// be added, they should be separated by a comma suitable for direct injection
// into a JSON array.
//
// See https://www.envoyproxy.io/docs/envoy/v1.9.0/api-v2/api/v2/lds.proto.
StaticListenersJSON string `mapstructure:"envoy_extra_static_listeners_json"`
// StatsSinksJSON is a JSON string containing zero or more StatsSink
// definititions. They are appended to the `stats_sinks` array at the top
// level of the bootstrap config. A single sink should be given as a plain
// object, if more than one is to be added, they should be separated by a
// comma suitable for direct injection into a JSON array.
//
// See
// https://www.envoyproxy.io/docs/envoy/v1.9.0/api-v2/config/metrics/v2/stats.proto#config-metrics-v2-statssink.
//
// If this is non-empty then it will override anything configured in
// StatsTags.
StatsSinksJSON string `mapstructure:"envoy_extra_stats_sinks_json"`
// StatsConfigJSON is a JSON string containing an object in the right format
// to be rendered as the body of the `stats_config` field at the top level of
// the bootstrap config. It's format may vary based on Envoy version used. See
// https://www.envoyproxy.io/docs/envoy/v1.9.0/api-v2/config/metrics/v2/stats.proto#envoy-api-msg-config-metrics-v2-statsconfig.
//
// If this is non-empty then it will override anything configured in
// StatsdURL or DogstatsdURL.
StatsConfigJSON string `mapstructure:"envoy_stats_config_json"`
// StatsFlushInterval is the time duration between Envoy stats flushes. It is
// in proto3 "duration" string format for example "1.12s" See
// https://developers.google.com/protocol-buffers/docs/proto3#json and
// https://www.envoyproxy.io/docs/envoy/v1.9.0/api-v2/config/bootstrap/v2/bootstrap.proto#bootstrap
StatsFlushInterval string `mapstructure:"envoy_stats_flush_interval"`
// TracingConfigJSON is a JSON string containing an object in the right format
// to be rendered as the body of the `tracing` field at the top level of
// the bootstrap config. It's format may vary based on Envoy version used.
// See https://www.envoyproxy.io/docs/envoy/v1.9.0/api-v2/config/trace/v2/trace.proto.
TracingConfigJSON string `mapstructure:"envoy_tracing_json"`
}
// Template returns the bootstrap template to use as a base.
func (c *BootstrapConfig) Template() string {
if c.OverrideJSONTpl != "" {
return c.OverrideJSONTpl
}
return bootstrapTemplate
}
func (c *BootstrapConfig) GenerateJSON(args *BootstrapTplArgs) ([]byte, error) {
if err := c.ConfigureArgs(args); err != nil {
return nil, err
}
t, err := template.New("bootstrap").Parse(c.Template())
if err != nil {
return nil, err
}
var buf bytes.Buffer
err = t.Execute(&buf, args)
if err != nil {
return nil, err
}
return buf.Bytes(), nil
}
// ConfigureArgs takes the basic template arguments generated from the command
// arguments and environment and modifies them according to the BootstrapConfig.
func (c *BootstrapConfig) ConfigureArgs(args *BootstrapTplArgs) error {
// Attempt to setup sink(s) from high-level config. Note the args are passed
// by ref and modified in place.
if err := c.generateStatsSinks(args); err != nil {
return err
}
if c.StatsConfigJSON != "" {
// StatsConfig overridden explicitly
args.StatsConfigJSON = c.StatsConfigJSON
} else {
// Attempt to setup tags from high-level config. Note the args are passed by
// ref and modified in place.
if err := c.generateStatsConfig(args); err != nil {
return err
}
}
if c.StaticClustersJSON != "" {
args.StaticClustersJSON = c.StaticClustersJSON
}
if c.StaticListenersJSON != "" {
args.StaticListenersJSON = c.StaticListenersJSON
}
// Setup prometheus if needed. This MUST happen after the Static*JSON is set above
if c.PrometheusBindAddr != "" {
if err := c.generatePrometheusConfig(args); err != nil {
return err
}
}
if c.TracingConfigJSON != "" {
args.TracingConfigJSON = c.TracingConfigJSON
}
if c.StatsFlushInterval != "" {
args.StatsFlushInterval = c.StatsFlushInterval
}
return nil
}
func (c *BootstrapConfig) generateStatsSinks(args *BootstrapTplArgs) error {
var stats_sinks []string
if c.StatsdURL != "" {
sinkJSON, err := c.generateStatsSinkJSON("envoy.statsd", c.StatsdURL)
if err != nil {
return err
}
stats_sinks = append(stats_sinks, sinkJSON)
}
if c.DogstatsdURL != "" {
sinkJSON, err := c.generateStatsSinkJSON("envoy.dog_statsd", c.DogstatsdURL)
if err != nil {
return err
}
stats_sinks = append(stats_sinks, sinkJSON)
}
if c.StatsSinksJSON != "" {
stats_sinks = append(stats_sinks, c.StatsSinksJSON)
}
if len(stats_sinks) > 0 {
args.StatsSinksJSON = "[\n" + strings.Join(stats_sinks, ",\n") + "\n]"
}
return nil
}
func (c *BootstrapConfig) generateStatsSinkJSON(name string, addr string) (string, error) {
// Resolve address ENV var
if len(addr) > 2 && addr[0] == '$' {
addr = os.Getenv(addr[1:])
}
u, err := url.Parse(addr)
if err != nil {
return "", fmt.Errorf("failed to parse %s sink address %q", name, addr)
}
var addrJSON string
switch u.Scheme {
case "udp":
addrJSON = `
"socket_address": {
"address": "` + u.Hostname() + `",
"port_value": ` + u.Port() + `
}
`
case "unix":
addrJSON = `
"pipe": {
"path": "` + u.Path + `"
}
`
default:
return "", fmt.Errorf("unsupported address protocol %q for %s sink",
u.Scheme, name)
}
return `{
"name": "` + name + `",
"config": {
"address": {
` + addrJSON + `
}
}
}`, nil
}
func (c *BootstrapConfig) generateStatsConfig(args *BootstrapTplArgs) error {
var tagJSONs []string
// Add some default tags if not already overridden
defaults := map[string]string{
"local_cluster": args.ProxyCluster,
}
for _, tag := range c.StatsTags {
parts := strings.SplitN(tag, "=", 2)
// If there is no equals, treat it as a boolean tag and just assign value of
// 1 e.g. "canary" will out put the tag "canary: 1"
v := "1"
if len(parts) == 2 {
v = parts[1]
}
k := strings.ToLower(parts[0])
tagJSON := `{
"tag_name": "` + k + `",
"fixed_value": "` + v + `"
}`
tagJSONs = append(tagJSONs, tagJSON)
// Remove this in case we override a default
delete(defaults, k)
}
for k, v := range defaults {
if v == "" {
// Skip stuff we just didn't have data for, this is only really the case
// in tests currently.
continue
}
tagJSON := `{
"tag_name": "` + k + `",
"fixed_value": "` + v + `"
}`
tagJSONs = append(tagJSONs, tagJSON)
}
if len(tagJSONs) > 0 {
// use_all_default_tags is true by default but we'll make it explicit!
args.StatsConfigJSON = `{
"stats_tags": [
` + strings.Join(tagJSONs, ",\n") + `
],
"use_all_default_tags": true
}`
}
return nil
}
func (c *BootstrapConfig) generatePrometheusConfig(args *BootstrapTplArgs) error {
host, port, err := net.SplitHostPort(c.PrometheusBindAddr)
if err != nil {
return fmt.Errorf("invalid prometheus_bind_addr: %s", err)
}
clusterJSON := `{
"name": "self_admin",
"connect_timeout": "5s",
"type": "STATIC",
"http_protocol_options": {},
"hosts": [
{
"socket_address": {
"address": "127.0.0.1",
"port_value": ` + args.AdminBindPort + `
}
}
]
}`
listenerJSON := `{
"name": "envoy_prometheus_metrics_listener",
"address": {
"socket_address": {
"address": "` + host + `",
"port_value": ` + port + `
}
},
"filter_chains": [
{
"filters": [
{
"name": "envoy.http_connection_manager",
"config": {
"stat_prefix": "envoy_prometheus_metrics",
"codec_type": "HTTP1",
"route_config": {
"name": "self_admin_route",
"virtual_hosts": [
{
"name": "self_admin",
"domains": [
"*"
],
"routes": [
{
"match": {
"path": "/metrics"
},
"route": {
"cluster": "self_admin",
"prefix_rewrite": "/stats/prometheus"
}
},
{
"match": {
"prefix": "/"
},
"direct_response": {
"status": 404
}
}
]
}
]
},
"http_filters": [
{
"name": "envoy.router"
}
]
}
}
]
}
]
}`
if args.StaticClustersJSON != "" {
clusterJSON = ",\n" + clusterJSON
}
args.StaticClustersJSON += clusterJSON
if args.StaticListenersJSON != "" {
listenerJSON = ",\n" + listenerJSON
}
args.StaticListenersJSON += listenerJSON
return nil
}