fix standalone v2 for sca (#8400)

Fix the Sampler to enable ASMStandaloneSampler also when SCA is enabled

Author: jandro996

dd-trace-core/src/main/java/datadog/trace/common/sampling/Sampler.java

@@ -36,9 +36,7 @@ final class Builder {
     public static Sampler forConfig(final Config config, final TraceConfig traceConfig) {
       Sampler sampler;
       if (config != null) {
-        if (!config.isApmTracingEnabled()
-            && (config.getAppSecActivation() == ProductActivation.FULLY_ENABLED
-                || config.getIastActivation() == ProductActivation.FULLY_ENABLED)) {
+        if (!config.isApmTracingEnabled() && isAsmEnabled(config)) {
           log.debug("APM is disabled. Only 1 trace per minute will be sent.");
           return new AsmStandaloneSampler(Clock.systemUTC());
         }
@@ -103,6 +101,12 @@ public static Sampler forConfig(final Config config, final TraceConfig traceConf
       return sampler;
     }
 
+    private static boolean isAsmEnabled(Config config) {
+      return config.getAppSecActivation() == ProductActivation.FULLY_ENABLED
+          || config.getIastActivation() == ProductActivation.FULLY_ENABLED
+          || config.isAppSecScaEnabled();
+    }
+
     public static Sampler forConfig(final Properties config) {
       return forConfig(Config.get(config), null);
     }

dd-trace-core/src/test/groovy/datadog/trace/common/sampling/SamplerTest.groovy

@@ -31,6 +31,19 @@ class SamplerTest extends DDSpecification{
     sampler instanceof AsmStandaloneSampler
   }
 
+  void "test that AsmStandaloneSampler is selected when apm tracing disabled and sca enabled is enabled"() {
+    setup:
+    System.setProperty("dd.apm.tracing.enabled", "false")
+    System.setProperty("dd.appsec.sca.enabled", "true")
+    Config config = new Config()
+
+    when:
+    Sampler sampler = Sampler.Builder.forConfig(config, null)
+
+    then:
+    sampler instanceof AsmStandaloneSampler
+  }
+
   void "test that AsmStandaloneSampler is not selected when apm tracing and asm not enabled"() {
     setup:
     System.setProperty("dd.apm.tracing.enabled", "false")

internal-api/src/main/java/datadog/trace/api/Config.java

@@ -3981,8 +3981,8 @@ public String getAgentlessLogSubmissionProduct() {
     return agentlessLogSubmissionProduct;
   }
 
-  public Boolean getAppSecScaEnabled() {
-    return appSecScaEnabled;
+  public boolean isAppSecScaEnabled() {
+    return appSecScaEnabled != null && appSecScaEnabled;
   }
 
   public boolean isAppSecRaspEnabled() {