SDK Health checks

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## X.X.X
 - Added a new flag, 'loadAPMScriptsAsync', which can load the APM related scripts automatically for Async implementations
+- Adding SDK health check requests after init
 - Adding remaining request queue size information to every request
 - Fixed a bug where unnecessary device ID merge information was sent to the server
 

cypress/integration/health_check.js

@@ -0,0 +1,37 @@
+/* eslint-disable require-jsdoc */
+var Countly = require("../../lib/countly");
+var hp = require("../support/helper");
+
+function initMain() {
+    Countly.init({
+        app_key: "YOUR_APP_KEY",
+        url: "https://try.count.ly",
+        test_mode: true
+    });
+}
+
+describe("Health Check tests ", () => {
+    it("Check if health check is sent at the beginning", () => {
+        hp.haltAndClearStorage(() => {
+            initMain();
+            cy.intercept("GET", "https://try.count.ly/i?**").as("getXhr");
+            cy.wait("@getXhr").then((xhr) => {
+                const url = new URL(xhr.request.url);
+
+                // Test the 'hc' parameter
+                const hcParam = url.searchParams.get("hc");
+                const hcParamObj = JSON.parse(hcParam);
+                expect(hcParamObj).to.eql({ el: 0, wl: 0, sc: -1, em: "\"\"" });
+
+                // Test the 'metrics' parameter
+                const metricsParam = url.searchParams.get("metrics");
+                expect(metricsParam).to.equal("{\"_app_version\":\"0.0\",\"_ua\":\"abcd\"}");
+
+                // check nothing in the request queue
+                cy.fetch_local_request_queue().then((rq) => {
+                    expect(rq.length).to.equal(0);
+                });
+            });
+        });
+    });
+});

lib/countly.js

@@ -164,6 +164,16 @@
         BOOMERANG_SRC: "https://cdn.jsdelivr.net/npm/countly-sdk-web@latest/plugin/boomerang/boomerang.min.js",
         CLY_BOOMERANG_SRC: "https://cdn.jsdelivr.net/npm/countly-sdk-web@latest/plugin/boomerang/countly_boomerang.js",
     };
+
+    /**
+     * Health check counters' local storage keys
+     */
+    var healthCheckCounterEnum = Object.freeze({
+        errorCount: "cly_hc_error_count",
+        warningCount: "cly_hc_warning_count",
+        statusCode: "cly_hc_status_code",
+        errorMessage: "cly_hc_error_message",
+    });
     /**
      *  Async api queue, push commands here to be executed when script is loaded or after
      *  @example <caption>Add command as array</caption>
@@ -295,6 +305,10 @@
             this.maxStackTraceLinesPerThread = getConfig("max_stack_trace_lines_per_thread", ob, configurationDefaultValues.MAX_STACKTRACE_LINES_PER_THREAD);
             this.maxStackTraceLineLength = getConfig("max_stack_trace_line_length", ob, configurationDefaultValues.MAX_STACKTRACE_LINE_LENGTH);
             this.heatmapWhitelist = getConfig("heatmap_whitelist", ob, []);
+            self.hcErrorCount = getValueFromStorage(healthCheckCounterEnum.errorCount) || 0;
+            self.hcWarningCount = getValueFromStorage(healthCheckCounterEnum.warningCount) || 0;
+            self.hcStatusCode = getValueFromStorage(healthCheckCounterEnum.statusCode) || -1;
+            self.hcErrorMessage = getValueFromStorage(healthCheckCounterEnum.errorMessage) || "";
 
             if (maxCrashLogs && !this.maxBreadcrumbCount) {
                 this.maxBreadcrumbCount = maxCrashLogs;
@@ -3756,6 +3770,13 @@
                 if (last - lastBeat > sessionUpdate) {
                     self.session_duration(last - lastBeat);
                     lastBeat = last;
+                    // save health check logging counters if there are any
+                    if (self.hcErrorCount > 0) {
+                        setValueInStorage(healthCheckCounterEnum.errorCount, self.hcErrorCount);
+                    }
+                    if (self.hcWarningCount > 0) {
+                        setValueInStorage(healthCheckCounterEnum.warningCount, self.hcWarningCount);
+                    }
                 }
             }
 
@@ -3941,10 +3962,12 @@
                 if (level === logLevelEnums.ERROR) {
                     // eslint-disable-next-line no-console
                     console.error(log);
+                    HealthCheck.incrementErrorCount();
                 }
                 else if (level === logLevelEnums.WARNING) {
                     // eslint-disable-next-line no-console
                     console.warn(log);
+                    HealthCheck.incrementWarningCount();
                 }
                 else if (level === logLevelEnums.INFO) {
                     // eslint-disable-next-line no-console
@@ -4019,8 +4042,11 @@
                         }
                         else {
                             log(logLevelEnums.ERROR, functionName + " Failed Server XML HTTP request, ", this.status);
+                            if (functionName === "send_request_queue") {
+                                HealthCheck.saveRequestCounters(this.status, this.responseText);
+                            }
                             if (typeof callback === "function") {
-                                callback(true, params);
+                                callback(true, params, this.status, this.responseText);
                             }
                         }
                     }
@@ -4491,7 +4517,101 @@
             }
         };
 
+        /**
+         * Health Check Interface:
+         * {sendInstantHCRequest} Sends instant health check request
+         * {resetAndSaveCounters} Resets and saves health check counters
+         * {incrementErrorCount} Increments health check error count
+         * {incrementWarningCount} Increments health check warning count
+         * {resetCounters} Resets health check counters
+         * {saveRequestCounters} Saves health check request counters
+         */
+        var HealthCheck = {};
+        HealthCheck.sendInstantHCRequest = sendInstantHCRequest;
+        HealthCheck.resetAndSaveCounters = resetAndSaveCounters;
+        HealthCheck.incrementErrorCount = incrementErrorCount;
+        HealthCheck.incrementWarningCount = incrementWarningCount;
+        HealthCheck.resetCounters = resetCounters;
+        HealthCheck.saveRequestCounters = saveRequestCounters;
+        /**
+         * Increments health check error count
+         */
+        function incrementErrorCount() {
+            self.hcErrorCount++;
+        }
+        /**
+         * Increments health check warning count
+         */
+        function incrementWarningCount() {
+            self.hcWarningCount++;
+        }
+        /**
+         * Resets health check counters
+         */
+        function resetCounters() {
+            self.hcErrorCount = 0;
+            self.hcWarningCount = 0;
+            self.hcStatusCode = -1;
+            self.hcErrorMessage = "";
+        }
+        /**
+         * Sets and saves the status code and error message counters 
+         * @param {number} status - response status code of the request
+         * @param {string} responseText - response text of the request
+         */
+        function saveRequestCounters(status, responseText) {
+            self.hcStatusCode = status;
+            self.hcErrorMessage = responseText;
+            setValueInStorage(healthCheckCounterEnum.statusCode, self.hcStatusCode);
+            setValueInStorage(healthCheckCounterEnum.errorMessage, self.hcErrorMessage);
+        }
+        /**
+         * Resets and saves health check counters
+         */
+        function resetAndSaveCounters() {
+            HealthCheck.resetCounters();
+            setValueInStorage(healthCheckCounterEnum.errorCount, self.hcErrorCount);
+            setValueInStorage(healthCheckCounterEnum.warningCount, self.hcWarningCount);
+            setValueInStorage(healthCheckCounterEnum.statusCode, self.hcStatusCode);
+            setValueInStorage(healthCheckCounterEnum.errorMessage, self.hcErrorMessage);
+        }
+        /**
+         * Countly health check request sender
+         */
+        function sendInstantHCRequest() {
+            // truncate error message to 1000 characters
+            var curbedMessage = truncateSingleValue(self.hcErrorMessage, 1000, "healthCheck", log);
+            // prepare hc object
+            var hc = {
+                el: self.hcErrorCount,
+                wl: self.hcWarningCount,
+                sc: self.hcStatusCode,
+                em: JSON.stringify(curbedMessage)
+            };
+            // prepare request
+            var request = {
+                hc: JSON.stringify(hc),
+                metrics: JSON.stringify({ _app_version: self.app_version })
+            };
+            // add common request params
+            prepareRequest(request);
+            // send request
+            sendXmlHttpRequest("healthCheck", self.url + apiPath, request, function(err, params, status, responseText) {
+                if (err) {
+                    log(logLevelEnums.ERROR, "healthCheck, An error occurred. Status: [" + status + "], response: [" + responseText + "]");
+                }
+                else {
+                    log(logLevelEnums.INFO, "healthCheck, Request was successful. Status: [" + status + "], response: [" + responseText + "]");
+                    // reset and save health check counters if request was successful
+                    HealthCheck.resetAndSaveCounters();
+                }
+            }, true);
+        }
+
+        // initialize Countly Class
         this.initialize();
+        // send instant health check request
+        HealthCheck.sendInstantHCRequest();
     };
 
     /**