feat(config): support loading secrets from files and directories

[tie]

This change adds a secrets backend that retrieves secrets from files and directories. For example, this is useful for loading secrets from systemd credentials directory and similar mechanisms.
E.g.

[secret.systemd_credentials]
type = "directory"
path = "$CREDENTIALS_DIRECTORY"
remove_trailing_whitespace = true

SECRET[systemd_credentials.password.txt] → $CREDENTIALS_DIRECTORY/password.txt

Closes #20747

References:

• Validation fails with --no-environment flag if environment variables are not defined #21270
• feat(http_client): Add token_file feature #20138 (review)

[bits-bot]

All committers have signed the CLA.

[jszwedko]

Apologies @tie ! This one fell off my radar. I found it again skimming open PRs. This looks like a great addition. I appreciate you adding the behavior tests.

[jszwedko]

Could you add a changelog fragment here? I attempted to, but I'm not able to push to this branch. You can apply this diff:

ffbf204849 - (HEAD -> tie/master) add changelog entry (32 seconds ago) <Jesse Szwedko>
diff --git a/changelog.d/add-file-secrets.enhancement.md b/changelog.d/add-file-secrets.enhancement.md
new file mode 100644
index 0000000000..6c80fe8540
--- /dev/null
+++ b/changelog.d/add-file-secrets.enhancement.md
@@ -0,0 +1,4 @@
+Vector now supports two additional back-ends for loading secrets: `file`, for leading a set of
+secrets from a JSON file, and `directory`, for loading secrets from a list of files.
+
+authors: tie

[tie]

@jszwedko, done.

[jszwedko]

Thank you!

[pront]

Can you please run:

./website/scripts/cue.sh fmt
CI=true make check-docs

and commit the result? I tried to do it but cannot push to the fork directly.

[tie]

@pront, done. Note that running ./website/scripts/cue.sh fmt changed many other unrelated files so I’ve only pushed the changes to website/cue/reference/configuration.cue.

[github-actions]

Regression Detector Results

Run ID: 8c3e08d5-2d29-4279-b8f7-7b92203ba859 Metrics dashboard

Baseline: dc441a2
Comparison: 96e5562

Performance changes are noted in the perf column of each table:

• ✅ = significantly better comparison variant performance
• ❌ = significantly worse comparison variant performance
• ➖ = no significant change in performance

No significant changes in experiment optimization goals

Confidence level: 90.00%
Effect size tolerance: |Δ mean %| ≥ 5.00%

There were no significant changes in experiment optimization goals at this confidence level and effect size tolerance.

Experiments ignored for regressions

Regressions in experiments with settings containing erratic: true are ignored.

perf	experiment	goal	Δ mean %	Δ mean % CI	links
➖	file_to_blackhole	egress throughput	-2.06	[-6.24, +2.12]

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	links
➖	otlp_http_to_blackhole	ingress throughput	+3.70	[+3.62, +3.79]
➖	socket_to_socket_blackhole	ingress throughput	+3.15	[+3.09, +3.21]
➖	datadog_agent_remap_datadog_logs_acks	ingress throughput	+3.14	[+2.96, +3.32]
➖	http_elasticsearch	ingress throughput	+2.52	[+2.37, +2.67]
➖	syslog_log2metric_splunk_hec_metrics	ingress throughput	+2.41	[+2.31, +2.51]
➖	otlp_grpc_to_blackhole	ingress throughput	+2.26	[+2.06, +2.46]
➖	http_text_to_http_json	ingress throughput	+1.37	[+1.22, +1.52]
➖	splunk_hec_route_s3	ingress throughput	+0.99	[+0.70, +1.28]
➖	syslog_log2metric_tag_cardinality_limit_blackhole	ingress throughput	+0.70	[+0.65, +0.76]
➖	syslog_log2metric_humio_metrics	ingress throughput	+0.52	[+0.41, +0.63]
➖	datadog_agent_remap_datadog_logs	ingress throughput	+0.06	[-0.12, +0.23]
➖	splunk_hec_indexer_ack_blackhole	ingress throughput	+0.00	[-0.02, +0.02]
➖	splunk_hec_to_splunk_hec_logs_noack	ingress throughput	-0.00	[-0.02, +0.02]
➖	http_to_http_noack	ingress throughput	-0.00	[-0.06, +0.05]
➖	http_to_http_json	ingress throughput	-0.00	[-0.05, +0.04]
➖	syslog_loki	ingress throughput	-0.01	[-0.06, +0.05]
➖	http_to_http_acks	ingress throughput	-0.03	[-0.52, +0.46]
➖	splunk_hec_to_splunk_hec_logs_acks	ingress throughput	-0.04	[-0.07, -0.01]
➖	syslog_splunk_hec_logs	ingress throughput	-0.40	[-0.47, -0.33]
➖	fluent_elasticsearch	ingress throughput	-0.60	[-1.14, -0.06]
➖	syslog_humio_logs	ingress throughput	-0.85	[-0.97, -0.73]
➖	datadog_agent_remap_blackhole_acks	ingress throughput	-0.93	[-1.01, -0.84]
➖	http_to_s3	ingress throughput	-0.96	[-1.14, -0.79]
➖	syslog_regex_logs2metric_ddmetrics	ingress throughput	-1.01	[-1.19, -0.84]
➖	file_to_blackhole	egress throughput	-2.06	[-6.24, +2.12]
➖	datadog_agent_remap_blackhole	ingress throughput	-4.61	[-4.80, -4.42]

Explanation

A regression test is an A/B test of target performance in a repeatable rig, where "performance" is measured as "comparison variant minus baseline variant" for an optimization goal (e.g., ingress throughput). Due to intrinsic variability in measuring that goal, we can only estimate its mean value for each experiment; we report uncertainty in that value as a 90.00% confidence interval denoted "Δ mean % CI".

For each experiment, we decide whether a change in performance is a "regression" -- a change worth investigating further -- if all of the following criteria are true:

1. Its estimated |Δ mean %| ≥ 5.00%, indicating the change is big enough to merit a closer look.

2. Its 90.00% confidence interval "Δ mean % CI" does not contain zero, indicating that if our statistical model is accurate, there is at least a 90.00% chance there is a difference in performance between baseline and comparison variants.

3. Its configuration does not mark it "erratic".

[tie]

make test-behavior failed because it tries to run vector test against all files in tests/behavior/config directory, including test data. I’ve moved these files to tests/data/secret-backends.

[jszwedko]

Aha, thanks @tie

[github-actions]

Regression Detector Results

Run ID: d3257d88-8f4e-4fde-a6c3-5ecbec24ceba Metrics dashboard

Baseline: 75c5a4d
Comparison: a8c0b6e

Performance changes are noted in the perf column of each table:

• ✅ = significantly better comparison variant performance
• ❌ = significantly worse comparison variant performance
• ➖ = no significant change in performance

Significant changes in experiment optimization goals

Confidence level: 90.00%
Effect size tolerance: |Δ mean %| ≥ 5.00%

perf	experiment	goal	Δ mean %	Δ mean % CI	links
✅	http_text_to_http_json	ingress throughput	+5.99	[+5.81, +6.16]

Experiments ignored for regressions

Regressions in experiments with settings containing erratic: true are ignored.

perf	experiment	goal	Δ mean %	Δ mean % CI	links
➖	file_to_blackhole	egress throughput	-3.09	[-7.24, +1.07]

Fine details of change detection per experiment

perf	experiment	goal	Δ mean %	Δ mean % CI	links
✅	http_text_to_http_json	ingress throughput	+5.99	[+5.81, +6.16]
➖	socket_to_socket_blackhole	ingress throughput	+4.06	[+3.98, +4.14]
➖	syslog_regex_logs2metric_ddmetrics	ingress throughput	+3.69	[+3.53, +3.85]
➖	http_elasticsearch	ingress throughput	+2.64	[+2.47, +2.80]
➖	fluent_elasticsearch	ingress throughput	+1.95	[+1.40, +2.50]
➖	otlp_http_to_blackhole	ingress throughput	+1.79	[+1.67, +1.90]
➖	datadog_agent_remap_blackhole	ingress throughput	+1.43	[+1.34, +1.52]
➖	syslog_log2metric_tag_cardinality_limit_blackhole	ingress throughput	+1.29	[+1.21, +1.37]
➖	splunk_hec_route_s3	ingress throughput	+1.01	[+0.69, +1.33]
➖	syslog_log2metric_humio_metrics	ingress throughput	+0.77	[+0.60, +0.95]
➖	http_to_s3	ingress throughput	+0.39	[+0.22, +0.56]
➖	datadog_agent_remap_blackhole_acks	ingress throughput	+0.02	[-0.07, +0.11]
➖	http_to_http_acks	ingress throughput	+0.01	[-0.48, +0.50]
➖	splunk_hec_indexer_ack_blackhole	ingress throughput	+0.00	[-0.02, +0.02]
➖	http_to_http_noack	ingress throughput	+0.00	[-0.06, +0.06]
➖	splunk_hec_to_splunk_hec_logs_acks	ingress throughput	+0.00	[-0.03, +0.03]
➖	splunk_hec_to_splunk_hec_logs_noack	ingress throughput	-0.00	[-0.02, +0.02]
➖	http_to_http_json	ingress throughput	-0.01	[-0.06, +0.04]
➖	syslog_humio_logs	ingress throughput	-0.62	[-0.71, -0.53]
➖	syslog_log2metric_splunk_hec_metrics	ingress throughput	-0.63	[-0.73, -0.53]
➖	syslog_loki	ingress throughput	-0.78	[-0.88, -0.68]
➖	datadog_agent_remap_datadog_logs_acks	ingress throughput	-0.89	[-1.06, -0.73]
➖	syslog_splunk_hec_logs	ingress throughput	-1.32	[-1.46, -1.19]
➖	otlp_grpc_to_blackhole	ingress throughput	-1.80	[-2.00, -1.60]
➖	file_to_blackhole	egress throughput	-3.09	[-7.24, +1.07]
➖	datadog_agent_remap_datadog_logs	ingress throughput	-3.70	[-3.93, -3.47]

Explanation

A regression test is an A/B test of target performance in a repeatable rig, where "performance" is measured as "comparison variant minus baseline variant" for an optimization goal (e.g., ingress throughput). Due to intrinsic variability in measuring that goal, we can only estimate its mean value for each experiment; we report uncertainty in that value as a 90.00% confidence interval denoted "Δ mean % CI".

For each experiment, we decide whether a change in performance is a "regression" -- a change worth investigating further -- if all of the following criteria are true:

1. Its estimated |Δ mean %| ≥ 5.00%, indicating the change is big enough to merit a closer look.

2. Its 90.00% confidence interval "Δ mean % CI" does not contain zero, indicating that if our statistical model is accurate, there is at least a 90.00% chance there is a difference in performance between baseline and comparison variants.

3. Its configuration does not mark it "erratic".