Deprecate IGNORE_URLS and replace with TRANSACTION_IGNORE_URLS (#811)

Closes #792

docs/configuration.asciidoc

@@ -258,12 +258,12 @@ server versions.
 
 [float]
 [[config-ignore-urls]]
-=== `ELASTIC_APM_IGNORE_URLS`
+=== `ELASTIC_APM_TRANSACTION_IGNORE_URLS`
 
 [options="header"]
 |============
-| Environment               | Default | Example
-| `ELASTIC_APM_IGNORE_URLS` |         | `/heartbeat*, *.jpg`
+| Environment                           | Default | Example
+| `ELASTIC_APM_TRANSACTION_IGNORE_URLS` |         | `/heartbeat*, *.jpg`
 |============
 
 A list of patterns to match HTTP requests to ignore. An incoming HTTP request
@@ -273,6 +273,9 @@ This option supports the wildcard `*`, which matches zero or more characters.
 Examples: `/foo/*/bar/*/baz*`, `*foo*`. Matching is case insensitive by default.
 Prefixing a pattern with `(?-i)` makes the matching case sensitive.
 
+NOTE: this configuration was previously known as `ELASTIC_APM_IGNORE_URLS`, which has been deprecated and will be removed in a future major
+version of the agent.
+
 [float]
 [[config-sanitize-field-names]]
 === `ELASTIC_APM_SANITIZE_FIELD_NAMES`

module/apmhttp/ignorer.go

@@ -27,7 +27,8 @@ import (
 )
 
 const (
-	envIgnoreURLs = "ELASTIC_APM_IGNORE_URLS"
+	envIgnoreURLs           = "ELASTIC_APM_TRANSACTION_IGNORE_URLS"
+	deprecatedEnvIgnoreURLs = "ELASTIC_APM_IGNORE_URLS"
 )
 
 var (
@@ -36,12 +37,15 @@ var (
 )
 
 // DefaultServerRequestIgnorer returns the default RequestIgnorer to use in
-// handlers. If ELASTIC_APM_IGNORE_URLS is set, it will be treated as a
+// handlers. If ELASTIC_APM_TRANSACTION_IGNORE_URLS is set, it will be treated as a
 // comma-separated list of wildcard patterns; requests that match any of the
 // patterns will be ignored.
 func DefaultServerRequestIgnorer() RequestIgnorerFunc {
 	defaultServerRequestIgnorerOnce.Do(func() {
 		matchers := configutil.ParseWildcardPatternsEnv(envIgnoreURLs, nil)
+		if len(matchers) == 0 {
+			matchers = configutil.ParseWildcardPatternsEnv(deprecatedEnvIgnoreURLs, nil)
+		}
 		if len(matchers) != 0 {
 			defaultServerRequestIgnorer = NewWildcardPatternsRequestIgnorer(matchers)
 		}

module/apmhttp/ignorer_test.go

@@ -61,11 +61,24 @@ func testDefaultServerRequestIgnorer(t *testing.T, ignoreURLs string, r *http.Re
 		if os.Getenv("_INSIDE_TEST") != "1" {
 			cmd := exec.Command(os.Args[0], "-test.run=^"+regexp.QuoteMeta(t.Name())+"$")
 			cmd.Env = append(os.Environ(), "_INSIDE_TEST=1")
-			cmd.Env = append(cmd.Env, "ELASTIC_APM_IGNORE_URLS="+ignoreURLs)
+			cmd.Env = append(cmd.Env, "ELASTIC_APM_TRANSACTION_IGNORE_URLS="+ignoreURLs)
 			assert.NoError(t, cmd.Run())
 			return
 		}
 		ignorer := apmhttp.DefaultServerRequestIgnorer()
 		assert.Equal(t, expect, ignorer(r))
 	})
 }
+
+func TestFallbackDeprecatedRequestIgnorer(t *testing.T) {
+	if os.Getenv("_INSIDE_TEST") != "1" {
+		cmd := exec.Command(os.Args[0], "-test.run=^"+regexp.QuoteMeta(t.Name())+"$")
+		cmd.Env = append(os.Environ(), "_INSIDE_TEST=1")
+		cmd.Env = append(cmd.Env, "ELASTIC_APM_IGNORE_URLS=*/foo*")
+		assert.NoError(t, cmd.Run())
+		return
+	}
+	req := &http.Request{URL: &url.URL{Path: "/foo"}}
+	ignorer := apmhttp.DefaultServerRequestIgnorer()
+	assert.Equal(t, true, ignorer(req))
+}