Telemetry with two implementations: basic usage logging and opentelemetry.io observability

pom.xml

@@ -155,7 +155,11 @@
 				<artifactId>hakunapi-cql2-functions</artifactId>
 				<version>${project.version}</version>
 			</dependency>
-
+            <dependency>
+                <groupId>fi.nls.hakunapi</groupId>
+                <artifactId>hakunapi-telemetry</artifactId>
+                <version>${project.version}</version>
+            </dependency>
 			<dependency>
 				<groupId>javax.servlet</groupId>
 				<artifactId>javax.servlet-api</artifactId>
@@ -265,6 +269,11 @@
 				<artifactId>log4j-core</artifactId>
 				<version>${log4j.version}</version>
 			</dependency>
+            <dependency>
+                <groupId>org.apache.logging.log4j</groupId>
+                <artifactId>log4j-web</artifactId>
+                <version>${log4j.version}</version>
+            </dependency>
 
 			<dependency>
 				<groupId>junit</groupId>

src/hakunapi-core/src/main/java/fi/nls/hakunapi/core/FeatureServiceConfig.java

@@ -13,6 +13,7 @@
 
 import fi.nls.hakunapi.core.schemas.ConformanceClasses;
 import fi.nls.hakunapi.core.schemas.FunctionsContent;
+import fi.nls.hakunapi.core.telemetry.ServiceTelemetry;
 import io.swagger.v3.oas.models.info.Info;
 import io.swagger.v3.oas.models.security.SecurityRequirement;
 import io.swagger.v3.oas.models.security.SecurityScheme;
@@ -36,6 +37,7 @@ public abstract class FeatureServiceConfig {
     protected FunctionsContent functionsContent;
     protected List<MetadataFormat> metadataFormats;
     protected List<SRIDCode> knownSrids;
+    protected ServiceTelemetry telemetry = ServiceTelemetry.NOP;
 
     public int getLimitDefault() {
         return limitDefault;
@@ -216,4 +218,13 @@ public String getApiKeyQueryParam() {
                 .filter(it -> it.getIn() == In.QUERY).findAny().map(it -> it.getName()).orElse(null);
     }
 
+    public ServiceTelemetry getTelemetry() {
+        return telemetry;
+    }
+
+    public void setTelemetry(ServiceTelemetry usage) {
+        this.telemetry = usage;
+    }
+
+
 }

src/hakunapi-core/src/main/java/fi/nls/hakunapi/core/telemetry/RequestTelemetry.java

@@ -0,0 +1,7 @@
+package fi.nls.hakunapi.core.telemetry;
+
+public interface RequestTelemetry {
+
+    public TelemetrySpan span();
+
+}

src/hakunapi-core/src/main/java/fi/nls/hakunapi/core/telemetry/ServiceTelemetry.java

@@ -0,0 +1,87 @@
+package fi.nls.hakunapi.core.telemetry;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.util.Map;
+
+import fi.nls.hakunapi.core.FeatureServiceConfig;
+import fi.nls.hakunapi.core.config.HakunaConfigParser;
+import fi.nls.hakunapi.core.request.GetFeatureRequest;
+
+public interface ServiceTelemetry extends Closeable {
+
+    public String getId();
+
+    public void setName(String name);
+    public String getName();
+    public void setHeaders(Map<String, String> headersMap) ;
+    public void setCollections(Map<String, String> collectionsMap);
+
+    public void parse(FeatureServiceConfig service, HakunaConfigParser parser);
+    public void start();
+
+    public RequestTelemetry forRequest(GetFeatureRequest r);
+
+
+    // No op implementation
+    static ServiceTelemetry NOP = new ServiceTelemetry() {
+
+        String name;
+        @Override
+        public RequestTelemetry forRequest(GetFeatureRequest r) {
+            return NOPFeatureTypeTelemetry.NOP;
+
+        }
+
+        @Override
+        public void setName(String name) {
+            this.name = name;                
+        }
+
+        @Override
+        public String getName() {
+            return name;
+        }
+
+        @Override
+        public void setHeaders(Map<String, String> headersMap) {
+        }
+
+        @Override
+        public String getId() {
+            return "nop";
+        }
+
+        @Override
+        public void setCollections(Map<String, String> collectionsMap) {
+        }
+
+        @Override
+        public void parse(FeatureServiceConfig service, HakunaConfigParser parser) {
+        }
+
+        @Override
+        public void start() {
+        }
+
+        @Override
+        public void close() throws IOException {
+        }
+
+    };
+
+    public static class NOPFeatureTypeTelemetry implements RequestTelemetry {
+
+
+        public static final NOPFeatureTypeTelemetry NOP = new NOPFeatureTypeTelemetry();
+
+        @Override
+        public TelemetrySpan span() {
+            return TelemetrySpan.NOP;
+        }
+    }
+
+
+
+
+}

src/hakunapi-core/src/main/java/fi/nls/hakunapi/core/telemetry/TelemetryConfigParser.java

@@ -0,0 +1,91 @@
+package fi.nls.hakunapi.core.telemetry;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import fi.nls.hakunapi.core.FeatureServiceConfig;
+import fi.nls.hakunapi.core.FeatureType;
+import fi.nls.hakunapi.core.config.HakunaConfigParser;
+
+public class TelemetryConfigParser {
+
+    private static final Logger LOG = LoggerFactory.getLogger(TelemetryConfigParser.class);
+
+    protected static final String TELEMETRY_LOG_NOP = "NOP";
+    public static final String TELEMETRY_MODULE_PROP = "telemetry.module.%s";
+    protected static final String TELEMETRY_MODE = "telemetry.mode";
+    protected static final String TELEMETRY_LOGGER = "telemetry.logger";
+    protected static final String TELEMETRY_FIELDS = "telemetry.fields";
+    protected static final String TELEMETRY_FIELDS_HEADER = "telemetry.fields.%s.header";
+    protected static final String TELEMETRY_COLLECTIONS = "telemetry.collections";
+    protected static final String TELEMETRY_COLLECTIONS_NAME = "telemetry.collections.%s.name";
+    protected static final String TELEMETRY_COLLECTIONS_WILDCARD = "*";
+
+
+    public static ServiceTelemetry parse(FeatureServiceConfig service, HakunaConfigParser parser) {
+
+        String telemetryId = parser.get(TELEMETRY_MODE, TELEMETRY_LOG_NOP);
+        if (TELEMETRY_LOG_NOP.equals(telemetryId)) {
+            LOG.info("Using no-op telemetry");
+            return ServiceTelemetry.NOP;
+        }
+
+        ServiceTelemetry telemetry = TelemetryProvider.getTelemetries().get(telemetryId);
+        if(telemetry==null) {
+            LOG.info("Telemetry not found "+telemetryId+". Using no-op telemetry");
+            return ServiceTelemetry.NOP;
+        }
+
+        LOG.info("Using telemetry "+telemetry.getClass().getName());
+
+        String usageLogName = parser.get(TELEMETRY_LOGGER);
+        telemetry.setName(usageLogName);
+
+        String[] headers = parser.getMultiple(TELEMETRY_FIELDS);
+
+        Map<String, String> headersMap = new HashMap<>();
+        telemetry.setHeaders(headersMap);
+        if (headers != null) {
+            for (String header : headers) {
+                String lookup = parser.get(String.format(TELEMETRY_FIELDS_HEADER, header), header);
+                headersMap.put(header, lookup);
+            }
+        }
+
+        String collectionsWildcard = parser.get(TELEMETRY_COLLECTIONS);
+        if (collectionsWildcard == null) {
+            return ServiceTelemetry.NOP;
+
+        } else if (service != null && TELEMETRY_COLLECTIONS_WILDCARD.equals(collectionsWildcard)) {
+            Collection<FeatureType> collections = service.getCollections();
+
+            // defaults to logging ft.name as ft.name
+            Map<String, String> collectionsMap = collections.stream()
+                    .collect(Collectors.toMap(FeatureType::getName, FeatureType::getName));
+            telemetry.setCollections(collectionsMap);
+
+        } else {
+            String[] collections = parser.getMultiple(TELEMETRY_COLLECTIONS);
+            Map<String, String> collectionsMap = new HashMap<>();
+            telemetry.setCollections(collectionsMap);
+
+            // defaults to logging ft.name as ft.name with optional rename
+            if (collections != null) {
+                for (String collection : collections) {
+                    String lookup = parser.get(String.format(TELEMETRY_COLLECTIONS_NAME, collection), collection);
+                    collectionsMap.put(collection, lookup);
+                }
+            }
+        }
+
+        telemetry.parse(service,parser);
+
+        return telemetry;
+    }
+
+}

src/hakunapi-core/src/main/java/fi/nls/hakunapi/core/telemetry/TelemetryFactory.java

@@ -0,0 +1,6 @@
+package fi.nls.hakunapi.core.telemetry;
+
+public interface TelemetryFactory {
+
+    public ServiceTelemetry createServiceTelemetry();
+}

src/hakunapi-core/src/main/java/fi/nls/hakunapi/core/telemetry/TelemetryProvider.java

@@ -0,0 +1,24 @@
+package fi.nls.hakunapi.core.telemetry;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.ServiceLoader;
+
+
+public class TelemetryProvider {
+
+    private static final ServiceLoader<TelemetryFactory> LOADER =
+        ServiceLoader.load(TelemetryFactory.class);
+
+    public static Map<String, ServiceTelemetry> getTelemetries() {
+        LOADER.reload();
+
+        final Map<String, ServiceTelemetry> telemetries = new HashMap<>();
+
+        for (TelemetryFactory factory : LOADER) {
+            ServiceTelemetry telemetry = factory.createServiceTelemetry();
+            telemetries.put(telemetry.getId(), telemetry);
+        }
+        return telemetries;
+    }
+}

src/hakunapi-core/src/main/java/fi/nls/hakunapi/core/telemetry/TelemetrySpan.java

@@ -0,0 +1,34 @@
+package fi.nls.hakunapi.core.telemetry;
+
+import fi.nls.hakunapi.core.request.WriteReport;
+
+public interface TelemetrySpan extends AutoCloseable {
+
+    void counts(int count);
+    void counts(WriteReport report);
+    void put(String key, String value);
+
+    public void close();
+
+    // No op implementation
+    TelemetrySpan NOP = new TelemetrySpan() {
+
+        @Override
+        public void close() {
+        }
+
+        @Override
+        public void counts(int count) {
+        }
+
+        @Override
+        public void counts(WriteReport report) {
+        }
+
+        @Override
+        public void put(String key, String value) {
+        }
+
+    };
+
+}