Publish a jar for zipkin-api to maven

[gneokleo]

The old thrift spec used to be published on zipkin here. Would it be possible to publish this as well? We use it to compile it and generate the java code.

[codefromthecrypt]

hmm.. not sure we want to encourage new use of thrift

[gneokleo]

I see. What would be the preferred binary serialization in v2 with cross language support?

[codefromthecrypt]

proto3, just we've had no end users asking about this recently, so haven't put forward the effort. There is some core infra in, so it isn't terribly difficult. wanna formally request it? https://github.com/openzipkin/zipkin/issues/new

[codefromthecrypt]

fyi we actually had an issue #39

[codefromthecrypt]

#47 for work in progress

[codefromthecrypt]

as "zipkin-api" especially in maven could be confused with a potentially future java interface, I think zipkin-proto3 makes more sense. Will set this up

[codefromthecrypt]

io.zipkin.proto3:zipkin-proto3 is waiting some process clearing from bintray, which will temporarily delay this to maven central. will ping back

[codefromthecrypt]

Note that io.zipkin.zipkin2:zipkin:2.8+ jar will include a dependency free codec like we used to have for thrift openzipkin/zipkin#1998

here's how to use this with normal protobuf, should you want to cc @devinsba @gneokleo @yurishkuro @basvanbeek @wu-sheng @jcchavezs

+    <protobuf.version>3.5.1</protobuf.version>

+    <dependency>
+      <groupId>io.zipkin.proto3</groupId>
+      <artifactId>zipkin-proto3</artifactId>
+      <version>0.1.0</version>
+    </dependency>
+    <dependency>
+      <groupId>com.google.protobuf</groupId>
+      <artifactId>protobuf-java</artifactId>
+      <version>${protobuf.version}</version>
+    </dependency>

+    <extensions>
+      <extension>
+        <groupId>kr.motd.maven</groupId>
+        <artifactId>os-maven-plugin</artifactId>
+        <version>1.5.0.Final</version>
+      </extension>
+    </extensions>

+      <!-- protobuf-maven-plugin cannot get proto definitions from dependencies, so we will -->
+      <plugin>
+        <artifactId>maven-dependency-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>unpack-proto</id>
+            <phase>generate-sources</phase>
+            <goals>
+              <goal>unpack-dependencies</goal>
+            </goals>
+            <configuration>
+              <includeArtifactIds>zipkin-proto3</includeArtifactIds>
+              <includes>**/*.proto</includes>
+              <outputDirectory>${project.build.directory}/proto</outputDirectory>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>org.xolstice.maven.plugins</groupId>
+        <artifactId>protobuf-maven-plugin</artifactId>
+        <version>0.5.1</version>
+        <executions>
+          <execution>
+            <goals>
+              <goal>compile</goal>
+            </goals>
+          </execution>
+        </executions>
+        <configuration>
+          <protoSourceRoot>${project.build.directory}/proto</protoSourceRoot>
+          <protocArtifact>
+            com.google.protobuf:protoc:${protobuf.version}:exe:${os.detected.classifier}
+          </protocArtifact>
+        </configuration>
+      </plugin>