fix: enforced max limit on metrics transmission config (#2511)

Author: abhilash-sivan

packages/core/src/config/index.js

@@ -73,6 +73,8 @@ const { validateStackTraceMode, validateStackTraceLength } = require('./configVa
 /** @type {String[]} */
 const allowedSecretMatchers = ['equals', 'equals-ignore-case', 'contains', 'contains-ignore-case', 'regex', 'none'];
 
+const transmissionDelayMaxValue = 5000;
+
 /**
  * @typedef {Object} InstanaConfig
  * @property {string} [serviceName]
@@ -223,6 +225,14 @@ function normalizeMetricsConfig(config) {
     'INSTANA_METRICS_TRANSMISSION_DELAY'
   );
 
+  // Validate max value for transmissionDelay
+  if (config.metrics.transmissionDelay > transmissionDelayMaxValue) {
+    logger.warn(
+      `The value of config.metrics.transmissionDelay (or INSTANA_METRICS_TRANSMISSION_DELAY) (${config.metrics.transmissionDelay}) exceeds the maximum allowed value of ${transmissionDelayMaxValue}. Assuming the max value ${transmissionDelayMaxValue}.`
+    );
+    config.metrics.transmissionDelay = transmissionDelayMaxValue;
+  }
+
   config.metrics.timeBetweenHealthcheckCalls =
     config.metrics.timeBetweenHealthcheckCalls || defaults.metrics.timeBetweenHealthcheckCalls;
 }

packages/core/test/config/normalizeConfig_test.js

@@ -70,10 +70,10 @@ describe('config.normalizeConfig', () => {
   it('should use custom metrics transmission settings from config', () => {
     const config = coreConfig.normalize({
       metrics: {
-        transmissionDelay: 9753
+        transmissionDelay: 753
       }
     });
-    expect(config.metrics.transmissionDelay).to.equal(9753);
+    expect(config.metrics.transmissionDelay).to.equal(753);
   });
 
   it('should use custom metrics transmission settings from env vars', () => {
@@ -88,6 +88,27 @@ describe('config.normalizeConfig', () => {
     expect(config.metrics.transmissionDelay).to.equal(1000);
   });
 
+  it('should use max metrics transmission settings when value exceeds max of 5000', () => {
+    process.env.INSTANA_METRICS_TRANSMISSION_DELAY = '6000';
+    const normalizedConfig = coreConfig.normalize();
+    expect(normalizedConfig.metrics.transmissionDelay).to.equal(5000);
+  });
+
+  it('should accept metrics transmission delay at max value of 5000', () => {
+    process.env.INSTANA_METRICS_TRANSMISSION_DELAY = '5000';
+    const normalizedConfig = coreConfig.normalize();
+    expect(normalizedConfig.metrics.transmissionDelay).to.equal(5000);
+  });
+
+  it('should use max metrics transmission settings when value exceeds max 5000', () => {
+    const config = coreConfig.normalize({
+      metrics: {
+        transmissionDelay: 9753
+      }
+    });
+    expect(config.metrics.transmissionDelay).to.equal(5000);
+  });
+
   it('should use custom config.metrics.timeBetweenHealthcheckCalls', () => {
     const config = coreConfig.normalize({
       metrics: {