From 99fd545d87df4c66a9f876a7813e3f3c761de18d Mon Sep 17 00:00:00 2001 From: Jaime Soriano Pastor Date: Wed, 2 Sep 2020 13:15:38 +0200 Subject: [PATCH] Avoid generating incomplete configurations in autodiscover (#20898) Handle errors when configuration unpacking fails. In principle this can only happen when some variable is missing, because configuration has been previously parsed as YAML. Errors on unpacking were previously ignored. When a variable is missing, this is clearly logged at the debug level. This changes the behaviour, previously an incomplete configuration was generated on this case. --- CHANGELOG.next.asciidoc | 2 ++ libbeat/autodiscover/template/config.go | 16 ++++++++-- libbeat/autodiscover/template/config_test.go | 31 ++++++++++++++++++++ 3 files changed, 47 insertions(+), 2 deletions(-) diff --git a/CHANGELOG.next.asciidoc b/CHANGELOG.next.asciidoc index c85bf81e5f3..534eda9d38e 100644 --- a/CHANGELOG.next.asciidoc +++ b/CHANGELOG.next.asciidoc @@ -20,6 +20,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d - Ensure dynamic template names are unique for the same field. {pull}18849[18849] - Remove the deprecated `xpack.monitoring.*` settings. Going forward only `monitoring.*` settings may be used. {issue}9424[9424] {pull}18608[18608] - Added `certificate` TLS verification mode to ignore server name mismatch. {issue}12283[12283] {pull}20293[20293] +- Autodiscover doesn't generate any configuration when a variable is missing. Previously it generated an incomplete configuration. {pull}20898[20898] *Auditbeat* @@ -167,6 +168,7 @@ https://github.com/elastic/beats/compare/v7.0.0-alpha2...master[Check the HEAD d - [Metricbeat][Kubernetes] Change cluster_ip field from ip to keyword. {pull}20571[20571] - Rename cloud.provider `az` value to `azure` inside the add_cloud_metadata processor. {pull}20689[20689] - Add missing country_name geo field in `add_host_metadata` and `add_observer_metadata` processors. {issue}20796[20796] {pull}20811[20811] +- Explicitly detect missing variables in autodiscover configuration, log them at the debug level. {issue}20568[20568] {pull}20898[20898] *Auditbeat* diff --git a/libbeat/autodiscover/template/config.go b/libbeat/autodiscover/template/config.go index a34cec10444..a1f87d2bcfc 100644 --- a/libbeat/autodiscover/template/config.go +++ b/libbeat/autodiscover/template/config.go @@ -18,7 +18,10 @@ package template import ( + "fmt" + "github.com/elastic/go-ucfg" + "github.com/elastic/go-ucfg/parse" "github.com/elastic/beats/v7/libbeat/common" "github.com/elastic/beats/v7/libbeat/common/bus" @@ -123,7 +126,16 @@ func ApplyConfigTemplate(event bus.Event, configs []*common.Config, options ...u if err != nil { logp.Err("Error building config: %v", err) } + opts := []ucfg.Option{ + // Catch-all resolve function to log fields not resolved in any other way, + // it needs to be the first resolver added, so it is executed the last one. + // Being the last one, its returned error will be the one returned by `Unpack`, + // this is important to give better feedback in case of failure. + ucfg.Resolve(func(name string) (string, parse.Config, error) { + return "", parse.Config{}, fmt.Errorf("field '%s' not available in event or environment", name) + }), + ucfg.PathSep("."), ucfg.Env(vars), ucfg.ResolveEnv, @@ -139,9 +151,9 @@ func ApplyConfigTemplate(event bus.Event, configs []*common.Config, options ...u } // Unpack config to process any vars in the template: var unpacked map[string]interface{} - c.Unpack(&unpacked, opts...) + err = c.Unpack(&unpacked, opts...) if err != nil { - logp.Err("Error unpacking config: %v", err) + logp.Debug("autodiscover", "Configuration template cannot be resolved: %v", err) continue } // Repack again: diff --git a/libbeat/autodiscover/template/config_test.go b/libbeat/autodiscover/template/config_test.go index 87e9ef5592a..7964ba24126 100644 --- a/libbeat/autodiscover/template/config_test.go +++ b/libbeat/autodiscover/template/config_test.go @@ -28,9 +28,12 @@ import ( "github.com/elastic/beats/v7/libbeat/common" "github.com/elastic/beats/v7/libbeat/common/bus" "github.com/elastic/beats/v7/libbeat/keystore" + "github.com/elastic/beats/v7/libbeat/logp" ) func TestConfigsMapping(t *testing.T) { + logp.TestingSetup() + config, _ := common.NewConfigFrom(map[string]interface{}{ "correct": "config", }) @@ -40,6 +43,13 @@ func TestConfigsMapping(t *testing.T) { "hosts": [1]string{"1.2.3.4:8080"}, }) + const envValue = "valuefromenv" + configFromEnv, _ := common.NewConfigFrom(map[string]interface{}{ + "correct": envValue, + }) + + os.Setenv("CONFIGS_MAPPING_TESTENV", envValue) + tests := []struct { mapping string event bus.Event @@ -79,6 +89,16 @@ func TestConfigsMapping(t *testing.T) { }, expected: []*common.Config{config}, }, + // No condition, value from environment + { + mapping: ` +- config: + - correct: ${CONFIGS_MAPPING_TESTENV}`, + event: bus.Event{ + "foo": 3, + }, + expected: []*common.Config{configFromEnv}, + }, // Match config and replace data.host and data.ports. properly { mapping: ` @@ -111,6 +131,17 @@ func TestConfigsMapping(t *testing.T) { }, expected: []*common.Config{configPorts}, }, + // Missing variable, config is not generated + { + mapping: ` +- config: + - module: something + hosts: ["${not.exists.host}"]`, + event: bus.Event{ + "host": "1.2.3.4", + }, + expected: nil, + }, } for _, test := range tests {