LZO is a splittable compression format for files stored in Hadoop’s HDFS. It has valuable combination of speed and compression size. Thanks to hadoop-lzo the .lzo files could be splittable too.
Install lzo and lzop codes [OSX].
$ brew install lzo lzop
Find where the headers and libraries are installed
If native libraries are not available the following message is displayed with every hadoop command: hadoop checknative
WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Clone hadoop source code
| // --------------------------------------------------------------------------------------------------------------------- | |
| // module build and dependencies | |
| // --------------------------------------------------------------------------------------------------------------------- | |
| apply plugin: "java" | |
| apply plugin: "idea" | |
| apply plugin: "maven-publish" | |
| if (!JavaVersion.current().java6Compatible) { | |
| throw new IllegalStateException("Must be built at least with Java 8") |
After installing Intellij IDEA 14 in OSX you can get a message that JRE 1.6 is required to run it. If you have already installed JDK1.7 or JDK1.8 do following changes:
$ cd /Applications/IntelliJ\ IDEA\ 14\ CE.app/Contents/
$ vim Info.plist
Change
<key>JVMVersion</key>
1.6*
Gradle - conflicting jar files (plugin) on classpath
If you get an issue related to incorrect jar files on classpath while invoking gradle plugin, move the plugin's tasks into seperate build file. Use GradleBuild task type with reference to seperated build file.
When developing small extension for ratpack manual I had to add gradle-js plugin with two tasks for combining javascript files into one file and then minifying it. Minification task thrown exception idicating that there are conflicting jar file versions for google's guava library:
java.lang.NoSuchMethodError: com.google.common.io.ByteStreams.limit
There is a bug in Groovy version up to 2.3.7. HTTPBuilder is not able to automatically parse chunked response to JSON format. If external server returns response with header:
Transfer-Encoding : chunked
Usually applied code:
def http = new HTTPBuilder(url)
def result = http.request(POST, JSON) { req ->
While developing application with external API calls stubs with some logic are mandatory. MounteBank provides bright and simple solution for stubbing HTTP API.
It is possible to start MounteBank server directly from command line and initialize its content with folllowing curl command:
$ mb
$ curl -X POST -d@./src/test/groovy/online4m/apigateway/si/test/imposter.json http://localhost:2525/imposters
To bind object instance to be accessible accross handlers and custom classes define module and provider method. Add @Singleton annotation to have one instance for all injections.
import com.google.inject.AbstractModule
import com.google.inject.Scopes
import com.google.inject.Provides
import com.google.inject.Singleton
class CallerModule extends AbstractModule {
Ratpack tests are based on Spock Framework.
To externalize properties from test cases, create new file in:
$ touch src/tests/resources/hipchat.properties
Put properties into the file:
auth_token=VALUE_OF_HIPCHAT_AUTH_TOKEN
When working on microservice API Gateway that is Ratpack based I encountered StackOverflowError thrown by groovy.json.JsonOutput.toJson() method.
Versions of groovyx.net.http.HTTPBuilder prior to 0.6 used internaly json-io library. As of version 0.6 it changed to native Groovy's JsonSlurper to cosume JSON.
If you use JsonOutput.toJson(groovyObject) and this groovyObject was generated by the following code:
def http = new HTTPBuilder(url)