Update Device Defender demo to send custom metrics

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog for AWS IoT Device SDK for Embedded C
 
+## 202103.00 (March 2021)
+
+### Major Changes
+
+ - [#1547](https://github.com/aws/aws-iot-device-sdk-embedded-C/pull/1547) This release updates the Device Defender demo to showcase reporting of custom metrics to the AWS IoT Device Defender service.
+
 ## 202012.01 (December 2020)
 
 ### Major Changes

demos/defender/defender_demo_json/defender_demo.c

@@ -135,6 +135,12 @@ static uint16_t openUdpPorts[ OPEN_UDP_PORTS_ARRAY_SIZE ];
  */
 static Connection_t establishedConnections[ ESTABLISHED_CONNECTIONS_ARRAY_SIZE ];
 
+/**
+ * @brief Memory to represent custom metrics of CPU usage time and memory statistics
+ * that this demo sends to the AWS IoT Defender service.
+ */
+static CustomMetrics_t customMetrics;
+
 /**
  * @brief All the metrics sent in the device defender report.
  */
@@ -410,6 +416,32 @@ static bool collectDeviceMetrics( void )
         }
     }
 
+    /* Collect CPU usage time metrics from the system.
+     * This is an example of a custom metric of number-list type. */
+    if( metricsCollectorStatus == MetricsCollectorSuccess )
+    {
+        metricsCollectorStatus = GetCpuUsageStats( &( customMetrics.cpuUsageStats ) );
+
+        if( metricsCollectorStatus != MetricsCollectorSuccess )
+        {
+            LogError( ( "GetCpuUsageStats failed. Status: %d.",
+                        metricsCollectorStatus ) );
+        }
+    }
+
+    /* Collect metrics of memory statistics from the system.
+     * This is an example of a custom metric of string-list type. */
+    if( metricsCollectorStatus == MetricsCollectorSuccess )
+    {
+        metricsCollectorStatus = GetMemoryStats( &( customMetrics.memoryStats ) );
+
+        if( metricsCollectorStatus != MetricsCollectorSuccess )
+        {
+            LogError( ( "GetMemoryStats failed. Status: %d.",
+                        metricsCollectorStatus ) );
+        }
+    }
+
     /* Populate device metrics. */
     if( metricsCollectorStatus == MetricsCollectorSuccess )
     {
@@ -421,6 +453,7 @@ static bool collectDeviceMetrics( void )
         deviceMetrics.openUdpPortsArrayLength = numOpenUdpPorts;
         deviceMetrics.pEstablishedConnectionsArray = &( establishedConnections[ 0 ] );
         deviceMetrics.establishedConnectionsArrayLength = numEstablishedConnections;
+        deviceMetrics.pCustomMetrics = &( customMetrics );
     }
 
     return status;

demos/defender/defender_demo_json/demo_config.h

@@ -194,10 +194,8 @@
 
 /**
  * @brief Size of the buffer which contains the generated device defender report.
- *
- * If the generated report is larger than this, it is rejected.
  */
-#define DEVICE_METRICS_REPORT_BUFFER_SIZE      1000
+#define DEVICE_METRICS_REPORT_BUFFER_SIZE      2000
 
 /**
  * @brief Major version number of the device defender report.

demos/defender/defender_demo_json/metrics_collector.c

@@ -36,8 +36,8 @@
 #include "metrics_collector.h"
 
 /**
- * @brief The maximum length of line read from any of /proc/net/dev, /proc/net/tcp
- * and /proc/net/udp.
+ * @brief The maximum length of line read from any of /proc/net/dev, /proc/net/tcp,
+ * /proc/net/udp, /proc/uptime and /proc/meminfo files.
  */
 #define MAX_LINE_LENGTH                  ( 256 )
 
@@ -47,6 +47,12 @@
 #define CONNECTION_STATUS_LISTEN         ( 10 )
 #define CONNECTION_STATUS_ESTABLISHED    ( 1 )
 
+/**
+ * @brief Fields from /proc/meminfo to use for memory statistics.
+ */
+#define TOTAL_MEM_FIELD                  "MemTotal"
+#define AVAILABLE_MEM_FIELD              "MemAvailable"
+
 /**
  * @brief Get a list of the open ports.
  *
@@ -378,4 +384,155 @@ MetricsCollectorStatus_t GetEstablishedConnections( Connection_t * pOutConnectio
 
     return status;
 }
+
 /*-----------------------------------------------------------*/
+
+MetricsCollectorStatus_t GetCpuUsageStats( CpuUsageStats_t * pCpuUsage )
+{
+    MetricsCollectorStatus_t status = MetricsCollectorSuccess;
+    FILE * fileHandle = NULL;
+    uint32_t filledVariables;
+    char lineBuffer[ MAX_LINE_LENGTH ];
+
+    if( pCpuUsage == NULL )
+    {
+        LogError( ( "Invalid parameter. pCpuUsage: %p", ( void * ) pCpuUsage ) );
+        status = MetricsCollectorBadParameter;
+    }
+
+    if( status == MetricsCollectorSuccess )
+    {
+        fileHandle = fopen( "/proc/uptime", "r" );
+
+        if( fileHandle == NULL )
+        {
+            LogError( ( "Failed to open /proc/uptime." ) );
+            status = MetricsCollectorFileOpenFailed;
+        }
+    }
+
+    if( status == MetricsCollectorSuccess )
+    {
+        if( fgets( &( lineBuffer[ 0 ] ), MAX_LINE_LENGTH, fileHandle ) != NULL )
+        {
+            LogDebug( ( "File: /proc/uptime, Content: %s.",
+                        &( lineBuffer[ 0 ] ) ) );
+
+            /* Parse the output. */
+            filledVariables = sscanf( &( lineBuffer[ 0 ] ),
+                                      "%u.%*u %u.%*u",
+                                      &( pCpuUsage->upTime ),
+                                      &( pCpuUsage->idleTime ) );
+
+            /* sscanf should fill all the 2 variables successfully. */
+            if( filledVariables != 2 )
+            {
+                LogError( ( "Failed to parse CPU usage data. File: /proc/uptime, Data: %s.", &( lineBuffer[ 0 ] ) ) );
+                status = MetricsCollectorParsingFailed;
+            }
+        }
+    }
+
+    if( fileHandle != NULL )
+    {
+        fclose( fileHandle );
+    }
+
+    return status;
+}
+/*-----------------------------------------------------------*/
+
+MetricsCollectorStatus_t GetMemoryStats( MemoryStats_t * pMemoryStats )
+{
+    MetricsCollectorStatus_t status = MetricsCollectorSuccess;
+    FILE * fileHandle = NULL;
+    /* Variables for reading and processing data from "/proc/meminfo" file. */
+    char lineBuffer[ MAX_LINE_LENGTH ];
+    bool readTotalMem = false, readAvailableMem = false;
+    int filledVariables = 0;
+
+    if( ( pMemoryStats == NULL ) )
+    {
+        LogError( ( "Invalid parameter. pMemoryStats: %p", ( void * ) pMemoryStats ) );
+        status = MetricsCollectorBadParameter;
+    }
+
+    if( status == MetricsCollectorSuccess )
+    {
+        fileHandle = fopen( "/proc/meminfo", "r" );
+
+        if( fileHandle == NULL )
+        {
+            LogError( ( "Failed to open /proc/meminfo." ) );
+            status = MetricsCollectorFileOpenFailed;
+        }
+    }
+
+    if( status == MetricsCollectorSuccess )
+    {
+        while( ( fgets( &( lineBuffer[ 0 ] ), MAX_LINE_LENGTH, fileHandle ) != NULL ) )
+        {
+            LogDebug( ( "File: /proc/meminfo, Content: %s.", &( lineBuffer[ 0 ] ) ) );
+
+            /* Check if the line read represents information for total memory in the system. */
+            if( strncmp( lineBuffer, TOTAL_MEM_FIELD, ( sizeof( TOTAL_MEM_FIELD ) - 1UL ) ) == 0 )
+            {
+                /* Extract the total memory value from the line. */
+                filledVariables = sscanf( lineBuffer,
+                                          "%*[^1-9]%u kB",
+                                          ( &pMemoryStats->totalMemory ) );
+
+                if( filledVariables != 1 )
+                {
+                    LogError( ( "Failed to parse data. File: /proc/meminfo, Content: %s", lineBuffer ) );
+                    status = MetricsCollectorParsingFailed;
+
+                    break;
+                }
+                else
+                {
+                    readTotalMem = true;
+                }
+            }
+            /* Check if the line read represents information for available memory in the system. */
+            else if( strncmp( lineBuffer, AVAILABLE_MEM_FIELD, ( sizeof( AVAILABLE_MEM_FIELD ) - 1UL ) ) == 0 )
+            {
+                /* Extract the total memory value from the line. */
+                filledVariables = sscanf( lineBuffer,
+                                          "%*[^1-9]%u kB",
+                                          ( &pMemoryStats->availableMemory ) );
+
+                if( filledVariables != 1 )
+                {
+                    LogError( ( "Failed to parse data. File: /proc/meminfo, Content: %s", lineBuffer ) );
+                    status = MetricsCollectorParsingFailed;
+
+                    break;
+                }
+                else
+                {
+                    readAvailableMem = true;
+                }
+            }
+
+            if( readTotalMem && readAvailableMem )
+            {
+                /* We have obtained data for both total and available memory in the system. */
+                status = MetricsCollectorSuccess;
+
+                break;
+            }
+            else
+            {
+                status = MetricsCollectorDataNotFound;
+            }
+        }
+    }
+
+    if( fileHandle != NULL )
+    {
+        fclose( fileHandle );
+    }
+
+    return status;
+}

demos/defender/defender_demo_json/metrics_collector.h

@@ -34,7 +34,8 @@ typedef enum
     MetricsCollectorSuccess = 0,
     MetricsCollectorBadParameter,
     MetricsCollectorFileOpenFailed,
-    MetricsCollectorParsingFailed
+    MetricsCollectorParsingFailed,
+    MetricsCollectorDataNotFound,
 } MetricsCollectorStatus_t;
 
 /**
@@ -59,6 +60,28 @@ typedef struct Connection
     uint16_t remotePort;
 } Connection_t;
 
+/**
+ * @brief Represents the Cpu Usage statistics obtained from "/proc/uptime".
+ * Refer to Linux manual for "/proc" filesystem for more information.
+ * https://man7.org/linux/man-pages/man5/procfs.5.html
+ */
+typedef struct CpuUsageData
+{
+    uint32_t upTime;   /**< Up-time of system in seconds. */
+    uint32_t idleTime; /**< Idle time of system in seconds. */
+} CpuUsageStats_t;
+
+/**
+ * @brief Represents the memory data of total and available memory from "/proc/uptime".
+ * Refer to Linux manual for "/proc" filesystem for more information.
+ * https://man7.org/linux/man-pages/man5/procfs.5.html
+ */
+typedef struct MemoryStats
+{
+    uint32_t totalMemory;     /**< Amount of total memory in system (in kB). */
+    uint32_t availableMemory; /**< Amount of available memory in system (in kB). */
+} MemoryStats_t;
+
 /**
  * @brief Get network stats.
  *
@@ -145,4 +168,34 @@ MetricsCollectorStatus_t GetEstablishedConnections( Connection_t * pOutConnectio
                                                     uint32_t connectionsArrayLength,
                                                     uint32_t * pOutNumEstablishedConnections );
 
+/**
+ * @brief Get CPU usage data of uptime and idle time from the system.
+ *
+ * This function finds the system CPU information by reading the "/proc/uptime" file.
+ *
+ * @param[out] pCpuUsage The memory to write the CPU usage statistics into.
+ *
+ * @return #MetricsCollectorSuccess if CPU usage data is successfully obtained;
+ * #MetricsCollectorBadParameter if invalid parameter is passed;
+ * #MetricsCollectorFileOpenFailed if the function fails to open "/proc/uptime";
+ * MetricsCollectorParsingFailed if the function fails to parses the data read
+ * from "/proc/uptime".
+ */
+MetricsCollectorStatus_t GetCpuUsageStats( CpuUsageStats_t * pCpuUsage );
+
+/**
+ * @brief Gets data of total and available memory from the system.
+ *
+ * This function finds the memory information by reading the "/proc/meminfo" file.
+ *
+ * @param[out] pMemoryStats The memory to write the memory information into.
+ *
+ * @return #MetricsCollectorSuccess if memory data statistic is successfully calculated;
+ * #MetricsCollectorBadParameter if invalid parameter is passed;
+ * #MetricsCollectorFileOpenFailed if the function fails to open "/proc/meminfo";
+ * MetricsCollectorParsingFailed if the function fails to parses the data read
+ * from "/proc/meminfo".
+ */
+MetricsCollectorStatus_t GetMemoryStats( MemoryStats_t * pMemoryStats );
+
 #endif /* ifndef METRICS_COLLECTOR_H_ */