Restructure script docker run example

Author: blootsvoets

README.md

@@ -2,43 +2,59 @@
 
 [![Build Status](https://travis-ci.org/RADAR-base/Restructure-HDFS-topic.svg?branch=master)](https://travis-ci.org/RADAR-base/Restructure-HDFS-topic)
 
-Data streamed to HDFS using the [RADAR HDFS sink connector](https://github.com/RADAR-CNS/RADAR-HDFS-Sink-Connector) is streamed to files based on sensor only. This package can transform that output to a local directory structure as follows: `userId/topic/date_hour.csv`. The date and hour is extracted from the `time` field of each record, and is formatted in UTC time.
+Data streamed to HDFS using the [RADAR HDFS sink connector](https://github.com/RADAR-CNS/RADAR-HDFS-Sink-Connector) is streamed to files based on sensor only. This package can transform that output to a local directory structure as follows: `userId/topic/date_hour.csv`. The date and hour is extracted from the `time` field of each record, and is formatted in UTC time. This package is included in the [RADAR-Docker](https://github.com/RADAR-CNS/RADAR-Docker) repository, in the `dcompose/radar-cp-hadoop-stack/hdfs_restructure.sh` script.
 
-## Usage
+## Docker usage
+
+This package is available as docker image [`radarbase/radar-hdfs-restructure`](https://hub.docker.com/r/radarbase/radar-hdfs-restructure). The entrypoint of the image is the current application. So in all of the commands listed in usage, replace `radar-hdfs-restructure` with for example:
+```shell
+docker run --rm -t --network hadoop -v "$PWD/output:/output" radarbase/radar-hdfs-restructure:0.4.0 -u hdfs://hdfs -o /output /myTopic
+```
+if your docker cluster is running in the `hadoop` network and your output directory should be `./output`.
 
-This package is included in the [RADAR-Docker](https://github.com/RADAR-CNS/RADAR-Docker) repository, in the `dcompose/radar-cp-hadoop-stack/hdfs_restructure.sh` script.
 
-## Advanced usage
+## Local build
 
-Build jar from source with
+This package requires at least Java JDK 8 . Build the distribution with
 
 ```shell
 ./gradlew build
 ```
-and find the output JAR file as `build/libs/restructurehdfs-0.3.3-all.jar`. Then run with:
+
+and install the package into `/usr/local` with for example
+```shell
+sudo mkdir -p /usr/local
+sudo tar -xzf build/distributions/radar-hdfs-restructure-0.4.0.tar.gz -C /usr/local --strip-components=1
+```
+
+Now the `radar-hdfs-restructure` command should be available.
+
+## Command line usage
+
+When the application is installed, it can be used as follows:
 
 ```shell
-java -jar restructurehdfs-0.3.3-all.jar --hdfs-uri <webhdfs_url> --output-directory <output_folder> <input_path_1> [<input_path_2> ...]
+radar-hdfs-restructure --hdfs-uri <webhdfs_url> --output-directory <output_folder> <input_path_1> [<input_path_2> ...]
 ```
 or you can use the short form as well like - 
 ```shell
-java -jar restructurehdfs-0.3.3-all.jar -u <webhdfs_url> -o <output_folder> <input_path_1> [<input_path_2> ...]
+radar-hdfs-restructure -u <webhdfs_url> -o <output_folder> <input_path_1> [<input_path_2> ...]
 ```
 
 To display the usage and all available options you can use the help option as follows - 
 ```shell
-java -jar restructurehdfs-0.3.3-all.jar --help
+radar-hdfs-restructure --help
 ```
 Note that the options preceded by the `*` in the above output are required to run the app. Also note that there can be multiple input paths from which to read the files. Eg - `/topicAndroidNew/topic1 /topicAndroidNew/topic2 ...`. At least one input path is required.
 
 By default, this will output the data in CSV format. If JSON format is preferred, use the following instead:
 ```shell
-java -jar restructurehdfs-0.3.3-all.jar --format json --hdfs-uri <webhdfs_url> --output-directory <output_folder>  <input_path_1> [<input_path_2> ...]
+radar-hdfs-restructure --format json --hdfs-uri <webhdfs_url> --output-directory <output_folder>  <input_path_1> [<input_path_2> ...]
 ```
 
 Another option is to output the data in compressed form. All files will get the `gz` suffix, and can be decompressed with a GZIP decoder. Note that for a very small number of records, this may actually increase the file size.
 ```
-java -jar restructurehdfs-0.3.3-all.jar --compression gzip  --hdfs-uri <webhdfs_url> --output-directory <output_folder> <input_path_1> [<input_path_2> ...]
+radar-hdfs-restructure --compression gzip  --hdfs-uri <webhdfs_url> --output-directory <output_folder> <input_path_1> [<input_path_2> ...]
 ```
 
 By default, files records are not deduplicated after writing. To enable this behaviour, specify the option `--deduplicate` or `-d`. This set to false by default because of an issue with Biovotion data. Please see - [issue #16](https://github.com/RADAR-base/Restructure-HDFS-topic/issues/16) before enabling it.