Repository: VictoriaMetrics/VictoriaMetrics
Pull request #6885 (2024-08-27 10:55:55)

vmagent: only remove default port for scrapeURL
### Describe Your Changes

https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6792

In the previous [pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/6798), the default ports (80/443) were removed for both the `scrapeURL` and `instance` label values for those targets without a port in `__address__`. Different values in the `instance` label generate new time series.

This pull request reverts the changes made to the `instance` label. Now, for those targets:
- `scrapeURL` will remain unchanged.
- The `instance` label value will include the default port.

### Checklist

The following checks are **mandatory**:

- [x] My change adheres [VictoriaMetrics contributing guidelines](https://docs.victoriametrics.com/contributing/).



Patch:
diff --git a/docs/changelog/CHANGELOG.md b/docs/changelog/CHANGELOG.md
index c237595fd..392facc3c 100644
--- a/docs/changelog/CHANGELOG.md
+++ b/docs/changelog/CHANGELOG.md
@@ -18,16 +18,13 @@ See also [LTS releases](https://docs.victoriametrics.com/lts-releases/).
 
 ## tip
 
-**Update note 1: The `external_labels` field in vmalert-tool [test file](https://docs.victoriametrics.com/vmalert-tool/#test-file-format) will be deprecated soon. Please use `-external.label` command-line flag instead, in the same way as vmalert uses it. This change is done for the sake of consistency between vmalert and vmalert-tool configuration. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6735).**
-
-**Update note 2: starting from this release, [vmagent](https://docs.victoriametrics.com/vmagent/) and [Single-node VictoriaMetrics](https://docs.victoriametrics.com/) will no longer add the default port 80/443 for scrape URLs without a specified port. 
-The value of `instance` label for those scrape targets will be changed from `<address>:<80|443>` to `<address>`, generating new time series. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6792) for details.**
+**Update note: The `external_labels` field in vmalert-tool [test file](https://docs.victoriametrics.com/vmalert-tool/#test-file-format) will be deprecated soon. Please use `-external.label` command-line flag instead, in the same way as vmalert uses it. This change is done for the sake of consistency between vmalert and vmalert-tool configuration. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6735).**
 
 * FEATURE: add `/influx/health` health-check handler for Influx endpoints. This is needed as some clients use the health endpoint to determine if the server is healthy and ready for data ingestion. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6653) for the details.
 * FEATURE: [vmctl](https://docs.victoriametrics.com/vmctl/): add `--vm-backoff-retries`, `--vm-backoff-factor`, `--vm-backoff-min-duration` and `--vm-native-backoff-retries`, `--vm-native-backoff-factor`, `--vm-native-backoff-min-duration` command-line flags. These flags allow to change backoff policy config for import requests to VictoriaMetrics. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6622).
 * FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent/): allow overriding the `sample_limit` option at [scrape_configs](https://docs.victoriametrics.com/sd_configs/#scrape_configs) when a label `__sample_limit__` is specified for target. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6665). Thanks to @zoglam for the [pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/6666).
 * FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent/): reduce memory usage when scraping targets with big response body. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6759).
-* FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent/) and [Single-node VictoriaMetrics](https://docs.victoriametrics.com/): stop adding default port 80/443 for scrape URLs without a port. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6792).
+* FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent/) and [Single-node VictoriaMetrics](https://docs.victoriametrics.com/): stop adding default port 80/443 for scrape URLs without a port. The value in `instance` label will still carry port for backward compatible. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6792).
 * FEATURE: [vmagent](https://docs.victoriametrics.com/vmagent.html): add flags `-remoteWrite.retryMinInterval` and `-remoteWrite.retryMaxTime` for adjusting remote-write requests retry policy. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/5486). Thanks to @yorik for the [pull request](https://github.com/VictoriaMetrics/VictoriaMetrics/pull/6289).
 * FEATURE: [vmalert](https://docs.victoriametrics.com/vmalert/): add command-line flag `-notifier.headers` to allow configuring additional headers for all requests sent to the corresponding `-notifier.url`.
 * FEATURE: [vmalert-tool](https://docs.victoriametrics.com/vmalert-tool/): add `-external.label` and `-external.url` command-line flags, in the same way as these flags are supported by vmalert. See [this issue](https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6735).
diff --git a/lib/promrelabel/scrape_url.go b/lib/promrelabel/scrape_url.go
index 7533d7547..cedbe6caf 100644
--- a/lib/promrelabel/scrape_url.go
+++ b/lib/promrelabel/scrape_url.go
@@ -38,6 +38,13 @@ func GetScrapeURL(labels *promutils.Labels, extraParams map[string][]string) (st
 		address = address[:n]
 	}
 
+	// If port is missing, typically it should be 80/443. This WAS written in a label and used as scrapeURL.
+	// However, adding the port by default can cause some issues, see: https://github.com/prometheus/prometheus/pull/9523#issuecomment-2059314966
+	// After https://github.com/VictoriaMetrics/VictoriaMetrics/issues/6792:
+	// - don't add the default port to scrapeURL.
+	// - continue adding the default port to the label value for backward compatibility and avoid generating new time series.
+	addressMustWithPort := addMissingPort(address, scheme == "https")
+
 	if !strings.HasPrefix(metricsPath, "/") {
 		metricsPath = "/" + metricsPath
 	}
@@ -51,7 +58,7 @@ func GetScrapeURL(labels *promutils.Labels, extraParams map[string][]string) (st
 	}
 	paramsStr := url.Values(params).Encode()
 	scrapeURL := buildScrapeURL(scheme, address, metricsPath, optionalQuestion, paramsStr)
-	return scrapeURL, address
+	return scrapeURL, addressMustWithPort
 }
 
 func getParamsFromLabels(labels *promutils.Labels, extraParams map[string][]string) map[string][]string {
@@ -89,4 +96,25 @@ func buildScrapeURL(scheme, address, metricsPath, optionalQuestion, paramsStr st
 	return s
 }
 
+func addMissingPort(addr string, isTLS bool) string {
+	if strings.Contains(addr, ":") {
+		return addr
+	}
+	if isTLS {
+		return concatTwoStrings(addr, ":443")
+	}
+	return concatTwoStrings(addr, ":80")
+}
+
+func concatTwoStrings(x, y string) string {
+	bb := bbPool.Get()
+	b := bb.B[:0]
+	b = append(b, x...)
+	b = append(b, y...)
+	s := bytesutil.InternBytes(b)
+	bb.B = b
+	bbPool.Put(bb)
+	return s
+}
+
 var bbPool bytesutil.ByteBufferPool


Test patch:
diff --git a/lib/promrelabel/scrape_url_test.go b/lib/promrelabel/scrape_url_test.go
index 7bdbdb5a1..8660bb9d0 100644
--- a/lib/promrelabel/scrape_url_test.go
+++ b/lib/promrelabel/scrape_url_test.go
@@ -24,35 +24,39 @@ func TestGetScrapeURL(t *testing.T) {
 	f(`{foo="bar"}`, "", "")
 
 	// __address__ without port
-	f(`{__address__="foo"}`, "http://foo/metrics", "foo")
+	f(`{__address__="foo"}`, "http://foo/metrics", "foo:80")
 
 	// __address__ with explicit port
 	f(`{__address__="foo:1234"}`, "http://foo:1234/metrics", "foo:1234")
 
 	// explicit __scheme__
-	f(`{__address__="foo",__scheme__="https"}`, "https://foo/metrics", "foo")
+	f(`{__address__="foo",__scheme__="https"}`, "https://foo/metrics", "foo:443")
 	f(`{__address__="foo:1234",__scheme__="https"}`, "https://foo:1234/metrics", "foo:1234")
 
 	// explicit __metrics_path__
-	f(`{__address__="foo",__metrics_path__="abc"}`, "http://foo/abc", "foo")
-	f(`{__address__="foo",__metrics_path__="/abc"}`, "http://foo/abc", "foo")
-	f(`{__address__="foo",__metrics_path__="/ab/c?d=ef&aa=bb"}`, "http://foo/ab/c?d=ef&aa=bb", "foo")
+	f(`{__address__="foo",__metrics_path__="abc"}`, "http://foo/abc", "foo:80")
+	f(`{__address__="foo",__metrics_path__="/abc"}`, "http://foo/abc", "foo:80")
+	f(`{__address__="foo",__metrics_path__="/ab/c?d=ef&aa=bb"}`, "http://foo/ab/c?d=ef&aa=bb", "foo:80")
 
 	// explitit __param_*
-	f(`{__address__="foo",__param_x="y"}`, "http://foo/metrics?x=y", "foo")
-	f(`{__address__="foo",__param_x="y",__param_y="aa"}`, "http://foo/metrics?x=y&y=aa", "foo")
-	f(`{__address__="foo",__param_x="y",__metrics_path__="?abc=de"}`, "http://foo/?abc=de&x=y", "foo")
-	f(`{__address__="foo",__param_abc="y",__metrics_path__="?abc=de"}`, "http://foo/?abc=de&abc=y", "foo")
+	f(`{__address__="foo",__param_x="y"}`, "http://foo/metrics?x=y", "foo:80")
+	f(`{__address__="foo",__param_x="y",__param_y="aa"}`, "http://foo/metrics?x=y&y=aa", "foo:80")
+	f(`{__address__="foo",__param_x="y",__metrics_path__="?abc=de"}`, "http://foo/?abc=de&x=y", "foo:80")
+	f(`{__address__="foo",__param_abc="y",__metrics_path__="?abc=de"}`, "http://foo/?abc=de&abc=y", "foo:80")
 
 	// __address__ with metrics path and/or scheme
-	f(`{__address__="foo/bar/baz?abc=de"}`, "http://foo/bar/baz?abc=de", "foo")
+	f(`{__address__="foo/bar/baz?abc=de"}`, "http://foo/bar/baz?abc=de", "foo:80")
 	f(`{__address__="foo:784/bar/baz?abc=de"}`, "http://foo:784/bar/baz?abc=de", "foo:784")
 	f(`{__address__="foo:784/bar/baz?abc=de",__param_xx="yy"}`, "http://foo:784/bar/baz?abc=de&xx=yy", "foo:784")
 	f(`{__address__="foo:784/bar/baz?abc=de",__param_xx="yy",__scheme__="https"}`, "https://foo:784/bar/baz?abc=de&xx=yy", "foo:784")
-	f(`{__address__="http://foo/bar/baz?abc=de",__param_xx="yy"}`, "http://foo/bar/baz?abc=de&xx=yy", "foo")
-	f(`{__address__="https://foo/bar/baz?abc=de",__param_xx="yy"}`, "https://foo/bar/baz?abc=de&xx=yy", "foo")
-
-	// __address__ with 80 or 443 as port
+	f(`{__address__="http://foo/bar/baz?abc=de",__param_xx="yy"}`, "http://foo/bar/baz?abc=de&xx=yy", "foo:80")
+	f(`{__address__="https://foo/bar/baz?abc=de",__param_xx="yy"}`, "https://foo/bar/baz?abc=de&xx=yy", "foo:443")
+
+	// __address__ already carry 80/443 port
+	f(`{__address__="foo:80"}`, "http://foo:80/metrics", "foo:80")
+	f(`{__address__="foo:443"}`, "http://foo:443/metrics", "foo:443")
+	f(`{__address__="http://foo"}`, "http://foo/metrics", "foo:80")
+	f(`{__address__="https://foo"}`, "https://foo/metrics", "foo:443")
 	f(`{__address__="http://foo:80"}`, "http://foo:80/metrics", "foo:80")
 	f(`{__address__="https://foo:443"}`, "https://foo:443/metrics", "foo:443")
 }
diff --git a/lib/promscrape/config_test.go b/lib/promscrape/config_test.go
index a73c5b5fd..84c1bd72f 100644
--- a/lib/promscrape/config_test.go
+++ b/lib/promscrape/config_test.go
@@ -229,7 +229,7 @@ scrape_configs:
 			ScrapeTimeout:  defaultScrapeTimeout,
 			MaxScrapeSize:  maxScrapeSize.N,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "host1",
+				"instance": "host1:80",
 				"job":      "abc",
 			}),
 			jobNameOriginal: "abc",
@@ -240,7 +240,7 @@ scrape_configs:
 			ScrapeTimeout:  defaultScrapeTimeout,
 			MaxScrapeSize:  maxScrapeSize.N,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "host2",
+				"instance": "host2:443",
 				"job":      "abc",
 			}),
 			jobNameOriginal: "abc",
@@ -464,7 +464,7 @@ scrape_configs:
 			ScrapeTimeout:  defaultScrapeTimeout,
 			MaxScrapeSize:  maxScrapeSize.N,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "host1",
+				"instance": "host1:80",
 				"job":      "foo",
 				"qwe":      "rty",
 			}),
@@ -476,7 +476,7 @@ scrape_configs:
 			ScrapeTimeout:  defaultScrapeTimeout,
 			MaxScrapeSize:  maxScrapeSize.N,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "host2",
+				"instance": "host2:80",
 				"job":      "foo",
 				"qwe":      "rty",
 			}),
@@ -695,7 +695,7 @@ scrape_configs:
 			ScrapeTimeout:  defaultScrapeTimeout,
 			MaxScrapeSize:  maxScrapeSize.N,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "s",
+				"instance": "s:80",
 				"job":      "aa",
 			}),
 			jobNameOriginal: "aa",
@@ -717,7 +717,7 @@ scrape_configs:
 			ScrapeTimeout:  defaultScrapeTimeout,
 			MaxScrapeSize:  maxScrapeSize.N,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "s",
+				"instance": "s:80",
 				"job":      "aa",
 			}),
 			jobNameOriginal: "aa",
@@ -739,7 +739,7 @@ scrape_configs:
 			ScrapeTimeout:  defaultScrapeTimeout,
 			MaxScrapeSize:  maxScrapeSize.N,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "s",
+				"instance": "s:80",
 				"job":      "aa",
 			}),
 			jobNameOriginal: "aa",
@@ -761,7 +761,7 @@ scrape_configs:
 			ScrapeTimeout:  defaultScrapeTimeout,
 			MaxScrapeSize:  maxScrapeSize.N,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "s",
+				"instance": "s:80",
 				"job":      "aa",
 			}),
 			jobNameOriginal: "aa",
@@ -853,7 +853,7 @@ scrape_configs:
 			HonorTimestamps: true,
 			DenyRedirects:   true,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "foo.bar",
+				"instance": "foo.bar:443",
 				"job":      "foo",
 				"x":        "y",
 			}),
@@ -869,7 +869,7 @@ scrape_configs:
 			HonorTimestamps: true,
 			DenyRedirects:   true,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "aaa",
+				"instance": "aaa:443",
 				"job":      "foo",
 				"x":        "y",
 			}),
@@ -882,7 +882,7 @@ scrape_configs:
 			ScrapeTimeout:  8 * time.Second,
 			MaxScrapeSize:  maxScrapeSize.N,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "1.2.3.4",
+				"instance": "1.2.3.4:80",
 				"job":      "qwer",
 			}),
 			jobNameOriginal: "qwer",
@@ -893,7 +893,7 @@ scrape_configs:
 			ScrapeTimeout:  8 * time.Second,
 			MaxScrapeSize:  maxScrapeSize.N,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
-				"instance": "foobar",
+				"instance": "foobar:80",
 				"job":      "asdf",
 			}),
 			jobNameOriginal: "asdf",
@@ -1109,7 +1109,7 @@ scrape_configs:
 			MaxScrapeSize:  maxScrapeSize.N,
 			Labels: promutils.NewLabelsFromMap(map[string]string{
 				"foo":      "bar",
-				"instance": "pp",
+				"instance": "pp:80",
 				"job":      "yyy",
 			}),
 			ExternalLabels: promutils.NewLabelsFromMap(map[string]string{