To create a new directory, you must be a registered user and must authenticate to QueryIO server. Provide a valid destination path to create a directory.
Following interfaces can be used to create a new directory:
Sample code below creates a new directory using DFS Client APIs. Apache Hadoop classes are used for this purpose.
import java.io.IOException;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hdfs.DFSConfigKeys;
public class PutDirectory {
/*
* This program creates directory on the specified path recursively.
*/
public static void main(String[] args) throws IOException{
Configuration conf = new Configuration(true); //Create a configuration object to define hdfs properties
conf.set(DFSConfigKeys.FS_DEFAULT_NAME_KEY, "hdfs://192.168.0.1:9000"); // URL for your namenode
conf.set(DFSConfigKeys.DFS_REPLICATION_KEY, "3"); // Replication count for files you write
//Initialize DFS FileSystem object with QueryIO configurations
FileSystem dfs = FileSystem.get(conf); //Returns the configured filesystem implementation.
dfs.mkdirs(new Path("/queryio/demo/")); //Create Directory Operation: Creates new directory named "demo".
}
}
FileSystem.mkdirs(path) creates a given directory and all non-existent parents into directory with the configuration provided. Path is the object of org.apache.Hadoop.fs.Path
To create a new directory using WEBHDFS API, curl command is used.
Syntax of curl command to create directory is:
curl -i -X PUT "http://<HOST>:<PORT>/<PATH>?op=MKDIRS[&user.name=<username>][&permission=<OCTAL>]"
-i option : Include the HTTP-header in the output like server-name, date of the document, HTTP-version etc. -X option : (HTTP) Specifies a custom request method to use when communicating with the HTTP server.PUT : submit HTTP PUT request.<HOST>: Hostname where directory has to be created.<PORT>: Port on which server is working.<PATH>: A valid path with directory name.<user.name>: Login id of QueryIO user.op=MKDIRS: PUT operation to perform.[&permission=<OCTAL>] : (optional)Permissions to be granted on directory in octal format. By default permissions granted to directory is 0755.Sample Request: curl -i -X PUT "http://192.168.0.1:50070/webhdfs/v1/queryio/demo?user.name=admin&op=MKDIRS&permission=0700"
Above request creates a directory "demo" with permission 700.
The following is the actual HTTP request:
PUT /webhdfs/v1/queryio/demo/a?user.name=admin&op=MKDIRS&permission=0700 HTTP/1.1 User-Agent: curl/7.21.4 (universal-apple-darwin11.0) libcurl/7.21.4 OpenSSL/0.9.8r zlib/1.2.5 Host: 192.168.0.16:50070 Accept: */*
Create directory operation using WEBHDFS API returns a JSON object. Following is the HTTP response sent when QueryIO Server successfully creates a directory:
HTTP/1.1 200 OK
Content-Type: application/json
Expires: Thu, 01-Jan-1970 00:00:00 GMT
Set-Cookie: hadoop.auth="u=admin&p=admin&t=simple&e=1356640714362&s=cicTFjtc8URHRKadmYxfj+ABcFM=";Path=/
Transfer-Encoding: chunked
Server: Jetty(6.1.26)
{"boolean":true}