Refactor the configuration

dd-trace/src/main/java/com/datadoghq/trace/resolver/DDTracerFactory.java

@@ -1,8 +1,5 @@
 package com.datadoghq.trace.resolver;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 import com.datadoghq.trace.DDTracer;
 import com.datadoghq.trace.sampling.AllSampler;
 import com.datadoghq.trace.sampling.RateSampler;
@@ -11,6 +8,8 @@ import com.datadoghq.trace.writer.DDAgentWriter;
 import com.datadoghq.trace.writer.DDApi;
 import com.datadoghq.trace.writer.LoggingWritter;
 import com.datadoghq.trace.writer.Writer;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Create a tracer from a configuration file
@@ -21,57 +20,69 @@ public class DDTracerFactory {
 
 	public static final String CONFIG_PATH = "dd-trace.yaml";
 
+	private static final String DD_AGENT_WRITER_TYPE = DDAgentWriter.class.getSimpleName();
+	private static final String LOGGING_WRITER_TYPE = LoggingWritter.class.getSimpleName();
+	private static final String ALL_SAMPLER_TYPE = AllSampler.class.getSimpleName();
+	private static final String RATE_SAMPLER_TYPE = RateSampler.class.getSimpleName();
+
 	/**
 	 * Create a tracer from a TracerConfig object
-	 * 
+	 *
 	 * @param config
 	 * @return the corresponding tracer
 	 */
-	public static DDTracer create(TracerConfig config){
+	public static DDTracer create(TracerConfig config) {
 		String defaultServiceName = config.getDefaultServiceName() != null ? config.getDefaultServiceName() : DDTracer.UNASSIGNED_DEFAULT_SERVICE_NAME;
 
 		//Create writer
-		Writer writer = DDTracer.UNASSIGNED_WRITER;
+		Writer writer;
-		if (config.getWriter() != null && config.getWriter().get("type") != null) {
+
-			String type = (String) config.getWriter().get("type");
+		if (config.getWriter() != null) {
-			if (type.equals(DDAgentWriter.class.getSimpleName())) {
+			WriterConfig c = config.getWriter();
-				String host = config.getWriter().get("host") != null ? (String) config.getWriter().get("host") : DDAgentWriter.DEFAULT_HOSTNAME;
+			if (DD_AGENT_WRITER_TYPE.equals(c.getType())) {
-				Integer port = config.getWriter().get("port") != null ? (Integer) config.getWriter().get("port") : DDAgentWriter.DEFAULT_PORT;
+				writer = new DDAgentWriter(new DDApi(c.getHost(DDAgentWriter.DEFAULT_HOSTNAME), c.getPort(DDAgentWriter.DEFAULT_PORT)));
-				DDApi api = new DDApi(host, port);
+			} else if (LOGGING_WRITER_TYPE.equals(c.getType())) {
-				writer = new DDAgentWriter(api);
-			} else if (type.equals(LoggingWritter.class.getSimpleName())) {
 				writer = new LoggingWritter();
+			} else {
+				writer = DDTracer.UNASSIGNED_WRITER;
 			}
+		} else {
+			writer = DDTracer.UNASSIGNED_WRITER;
+
 		}
 
 		//Create sampler
-		Sampler rateSampler = DDTracer.UNASSIGNED_SAMPLER;
+		Sampler sampler;
-		if (config.getSampler() != null && config.getSampler().get("type") != null) {
+
-			String type = (String) config.getSampler().get("type");
+		if (config.getSampler() != null) {
-			if (type.equals(AllSampler.class.getSimpleName())) {
+			if (RATE_SAMPLER_TYPE.equals(config.getSampler().getType())) {
-				rateSampler = new AllSampler();
+				sampler = new RateSampler(config.getSampler().getRate());
-			} else if (type.equals(RateSampler.class.getSimpleName())) {
+			} else if (ALL_SAMPLER_TYPE.equals(config.getSampler().getType())) {
-				rateSampler = new RateSampler((Double) config.getSampler().get("rate"));
+				sampler = new AllSampler();
+			} else {
+				sampler = DDTracer.UNASSIGNED_SAMPLER;
 			}
+		} else {
+			sampler = DDTracer.UNASSIGNED_SAMPLER;
 		}
 
 		//Create tracer
-		return new DDTracer(defaultServiceName, writer, rateSampler);
+		return new DDTracer(defaultServiceName, writer, sampler);
+
 	}
 
 
-	
+	public static DDTracer createFromResources() {
-	public static DDTracer createFromResources(){
 		TracerConfig tracerConfig = FactoryUtils.loadConfigFromResource(CONFIG_PATH, TracerConfig.class);
-		
+
 		DDTracer tracer = null;
 		if (tracerConfig == null) {
-			logger.info("No valid configuration file {} found. Loading default tracer.",CONFIG_PATH);
+			logger.info("No valid configuration file {} found. Loading default tracer.", CONFIG_PATH);
 			tracer = new DDTracer();
-		}else{
+		} else {
 			tracer = DDTracerFactory.create(tracerConfig);
 		}
-		
+
 		return tracer;
 	}
 

dd-trace/src/main/java/com/datadoghq/trace/resolver/TracerConfig.java

@@ -1,48 +1,56 @@
 package com.datadoghq.trace.resolver;
 
-import java.util.List;
-import java.util.Map;
-
 import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;
 
+import java.util.List;
+
 /**
  * Tracer configuration
  */
 @JsonIgnoreProperties(ignoreUnknown = true)
 public class TracerConfig {
+
 	private String defaultServiceName;
-	private Map<String,Object> writer;
+	private WriterConfig writer;
-	private Map<String,Object> sampler;
+	private SamplerConfig sampler;
 	private List<DDSpanDecoratorConfig> decorators;
-	
+
+
 	public String getDefaultServiceName() {
 		return defaultServiceName;
 	}
+
 	public void setDefaultServiceName(String defaultServiceName) {
 		this.defaultServiceName = defaultServiceName;
 	}
-	public Map<String, Object> getWriter() {
+
+	public WriterConfig getWriter() {
 		return writer;
 	}
-	public void setWriter(Map<String, Object> writer) {
+
+	public void setWriter(WriterConfig writer) {
 		this.writer = writer;
 	}
-	public Map<String, Object> getSampler() {
+
+	public SamplerConfig getSampler() {
 		return sampler;
 	}
-	public void setSampler(Map<String, Object> sampler) {
+
+	public void setSampler(SamplerConfig sampler) {
 		this.sampler = sampler;
 	}
+
 	public List<DDSpanDecoratorConfig> getDecorators() {
 		return decorators;
 	}
+
 	public void setDecorators(List<DDSpanDecoratorConfig> decorators) {
 		this.decorators = decorators;
 	}
-	
+
 	@Override
 	public String toString() {
 		try {
@@ -52,4 +60,71 @@ public class TracerConfig {
 			return null;
 		}
 	}
+
+}
+
+class SamplerConfig {
+
+
+	private Double rate;
+	private String type;
+
+	public String getType() {
+		return type;
+	}
+
+	public Double getRate() {
+		return rate;
+	}
+
+
+	public void setRate(Double rate) {
+		this.rate = rate;
+	}
+
+	public void setType(String type) {
+		this.type = type;
+	}
+}
+
+
+class WriterConfig {
+
+
+	private String host;
+	private Integer port;
+	private String type;
+
+	public void setHost(String host) {
+		this.host = host;
+	}
+
+	public void setPort(Integer port) {
+		this.port = port;
+	}
+
+	public void setType(String type) {
+		this.type = type;
+	}
+
+	public String getHost() {
+		return host;
+	}
+
+	public Integer getPort() {
+		return port;
+	}
+
+	public String getType() {
+		return type;
+	}
+
+	public String getHost(String defaultHostname) {
+		return host == null ? defaultHostname : host;
+	}
+
+
+	public Integer getPort(int defaultPort) {
+		return port == null ? defaultPort : port;
+	}
 }

dd-trace/src/test/java/com/datadoghq/trace/resolver/DDTracerFactoryTest.java

@@ -0,0 +1,44 @@
+package com.datadoghq.trace.resolver;
+
+import com.datadoghq.trace.sampling.AllSampler;
+import com.datadoghq.trace.sampling.RateSampler;
+import com.datadoghq.trace.writer.DDAgentWriter;
+import org.assertj.core.api.Assertions;
+import org.junit.Before;
+import org.junit.Test;
+
+import static org.assertj.core.api.Java6Assertions.assertThat;
+
+public class DDTracerFactoryTest {
+
+
+
+
+	@Test
+	public void test() throws Exception {
+		TracerConfig tracerConfig = FactoryUtils.loadConfigFromResource("dd-trace-1.yaml", TracerConfig.class);
+
+		assertThat(tracerConfig.getWriter()).isNotNull();
+		assertThat(tracerConfig.getSampler()).isNotNull();
+		assertThat(tracerConfig.getDefaultServiceName()).isEqualTo("java-app");
+		assertThat(tracerConfig.getWriter().getHost()).isEqualTo("foo");
+		assertThat(tracerConfig.getWriter().getPort()).isEqualTo(123);
+		assertThat(tracerConfig.getWriter().getType()).isEqualTo(DDAgentWriter.class.getSimpleName());
+		assertThat(tracerConfig.getSampler().getType()).isEqualTo(AllSampler.class.getSimpleName());
+		assertThat(tracerConfig.getSampler().getRate()).isNull();
+
+
+		tracerConfig = FactoryUtils.loadConfigFromResource("dd-trace-2.yaml", TracerConfig.class);
+		assertThat(tracerConfig.getWriter()).isNotNull();
+		assertThat(tracerConfig.getDefaultServiceName()).isEqualTo("java-app");
+		assertThat(tracerConfig.getWriter().getHost("localhost")).isEqualTo("localhost");
+		assertThat(tracerConfig.getWriter().getPort(8126)).isEqualTo(8126);
+		assertThat(tracerConfig.getWriter().getType()).isEqualTo(DDAgentWriter.class.getSimpleName());
+		assertThat(tracerConfig.getSampler().getType()).isEqualTo(RateSampler.class.getSimpleName());
+		assertThat(tracerConfig.getSampler().getRate()).isEqualTo(0.4);
+
+
+
+	}
+
+}

dd-trace/src/test/resources/dd-trace-1.yaml

@@ -0,0 +1,24 @@
+# Service name used if none is provided in the app
+defaultServiceName: java-app
+
+# The writer to use.
+# Could be: LoggingWritter or DDAgentWriter (default)
+writer:
+  # LoggingWriter: Spans are logged using the application configuration
+  # DDAgentWriter: Spans are forwarding to a Datadog Agent
+  #  - Param 'host': the hostname where the DD Agent running (default: localhost)
+  #  - Param 'port': the port to reach the DD Agent (default: 8126)
+  type: DDAgentWriter
+  host: foo
+  port: 123
+
+# The sampler to use.
+# Could be: AllSampler (default) or RateSampler
+sampler:
+  # AllSampler: all spans are reported to the writer
+  # RateSample: only a portion of spans are reported to the writer
+  #  - Param 'rate': the portion of spans to keep
+  type: AllSampler
+  
+# Enable custom tracing (annotations)
+# enableCustomTracing: true

dd-trace/src/test/resources/dd-trace-2.yaml

@@ -0,0 +1,23 @@
+# Service name used if none is provided in the app
+defaultServiceName: java-app
+
+# The writer to use.
+# Could be: LoggingWritter or DDAgentWriter (default)
+writer:
+  # LoggingWriter: Spans are logged using the application configuration
+  # DDAgentWriter: Spans are forwarding to a Datadog Agent
+  #  - Param 'host': the hostname where the DD Agent running (default: localhost)
+  #  - Param 'port': the port to reach the DD Agent (default: 8126)
+  type: DDAgentWriter
+
+# The sampler to use.
+# Could be: AllSampler (default) or RateSampler
+sampler:
+  # AllSampler: all spans are reported to the writer
+  # RateSample: only a portion of spans are reported to the writer
+  #  - Param 'rate': the portion of spans to keep
+  type: RateSampler
+  rate: 0.4
+  
+# Enable custom tracing (annotations)
+# enableCustomTracing: true