Supported file URL formats for Readers

Development > Component reference > Readers > Common properties of Readers > Supported file URL formats for Readers

The File URL attribute may be defined using the URL File Dialog.

To ensure graph portability, forward slashes must be used when defining the path in URLs (even on Microsoft Windows).

Below are examples of possible URL for Readers:

Reading of local files

/path/filename.txt

Reads a specified file.
/path1/filename1.txt;/path2/filename2.txt

Reads two specified files.
/path/filename?.txt

Reads all files satisfying the mask.
/path/*

Reads all files in a specified directory.
zip:(/path/file.zip)

Reads the first file compressed in the file.zip file.
zip:(/path/file.zip)!innerfolder/filename.txt

Reads a specified file compressed in the file.zip file.

Path separator character ! is supported since CloverDX version 6.4, and should be used instead of old separator character #. The old separator character is still supported for backward compatibility.

gzip:(/path/file.gz)

Reads the first file compressed in the file.gz file.
tar:(/path/file.tar)!innerfolder/filename.txt

Reads a specified file archived in the file.tar file.
zip:(/path/file??.zip)!innerfolder?/filename.*

Reads all files from the compressed zip file(s) that satisfy the specified mask. Wild cards (? and *) may be used in the compressed file names, inner folder and inner file names.
tar:(/path/file????.tar)!innerfolder??/filename*.txt

Reads all files from the archive file(s) that satisfy the specified mask. Wild cards (? and *) may be used in the compressed file names, inner folder and inner file names.
gzip:(/path/file*.gz)

Reads all files that has been gzipped into the file that satisfy the specified mask. Wild cards may be used in the compressed file names.
tar:(gzip:/path/file.tar.gz)!innerfolder/filename.txt

Reads a specified file compressed in the file.tar.gz file.

Although CloverDX can read data from a .tar file, writing to .tar files is not supported.

tar:(gzip:/path/file??.tar.gz)!innerfolder?/filename*.txt

Reads all files from the gzipped tar archive file(s) that satisfy the specified mask. Wild cards (? and *) may be used in the compressed file names, inner folder and inner file names.
zip:(zip:(/path/name?.zip)!innerfolder/file.zip)!innermostfolder?/filename*.txt

Reads all files satisfying the file mask from all paths satisfying the path mask from all compressed files satisfying the specified zip mask. Wild cards (? and *) may be used in the outer compressed files, innermost folder and innermost file names. They cannot be used in the inner folder and inner zip file names.

Reading of remote files

ftp://username:password@server/path/filename.txt

Reads a specified filename.txt file on a remote server connected via an FTP protocol using username and password.
sftp://username:password@server/path/filename.txt

Reads a specified filename.txt file on a remote server connected via an SFTP protocol using a username and password.

If a certificate-based authentication is used, certificates are placed in the ${PROJECT}/ssh-keys/ directory. For more information, see SFTP certificate in CloverDX.

The certificate-based authentication has a URL without a password:

sftp://username@server/path/filename.txt
http://server/path/filename.txt

Reads a specified filename.txt file on a remote server connected via an HTTP protocol.
https://server/path/filename.txt

Reads a specified filename.txt file on a remote server connected via an HTTPS protocol.
zip:(ftp://username:password@server/path/file.zip)!innerfolder/filename.txt

Reads a specified filename.txt file compressed in the file.zip file on a remote server connected via an FTP protocol using username and password.
zip:(http://server/path/file.zip)!innerfolder/filename.txt

Reads a specified filename.txt file compressed in the file.zip file on a remote server connected via an HTTP protocol.
tar:(ftp://username:password@server/path/file.tar)!innerfolder/filename.txt

Reads a specified filename.txt file archived in the file.tar file on a remote server connected via an FTP protocol using username and password.
zip:(zip:(ftp://username:password@server/path/name.zip)!innerfolder/file.zip)!innermostfolder/filename.txt

Reads a specified filename.txt file compressed in the file.zip file that is also compressed in the name.zip file on a remote server connected via an FTP protocol using username and password.
gzip:(http://server/path/file.gz)

Reads the first file compressed in the file.gz file on a remote server connected via an HTTP protocol.
http://server/filename*.dat

Reads all files from a WebDAV server which satisfy specified mask (only * is supported).
s3://access_key_id:secret_access_key@s3.amazonaws.com/bucketname/filename*.out

Reads all objects which satisfy the specified mask from an Amazon S3 web storage service from a given bucket using access key ID and a secret access key.

It is recommended to connect to S3 via region-specific S3 URL: s3://s3.eu-central-1.amazonaws.com/bucket.name/. The region-specific URL has much better performance than the generic one (s3://s3.amazonaws.com/bucket.name/).

See recommendation on Amazon S3 URL.

s3:// URL protocol is available since CloverETL 4.1. More information about the deprecated http:// S3 protocol can be found in CloverDX 4.0 User Guide.
az-blob://account:account_key@account.blob.core.windows.net/containername/path/filename*.txt

Reads all objects matching the specified mask from the specified container in Microsoft Azure Blob Strage service.

Connects using the specified Account Key. See Azure Blob Storage for other authentication options.
hdfs://CONN_ID/path/filename.dat

Reads a file from the Hadoop distributed file system (HDFS). To which HDFS NameNode to connect to is defined in a Hadoop connection with CONN_ID. This example file URL reads a file with the /path/filename.dat absolute HDFS path.
smb://domain%3Buser:password@server/path/filename.txt

Reads files from Windows share (Microsoft SMB/CIFS protocol) version 1. The URL path may contain wildcards (both * and ? are supported). The server part may be a DNS name, an IP address or a NetBIOS name. The Userinfo part of the URL (domain%3Buser:password) is not mandatory and any URL reserved character it contains should be escaped using the %-encoding similarly to the semicolon ; character with %3B in the example (the semicolon is escaped because it collides with the default CloverDX file URL separator).

The SMB protocol is implemented in the JCIFS library which may be configured using Java system properties. See Setting client properties in the JCIFS documentation for the list of all configurable properties.
smb2://domain%3Buser:password@server/path/filename.txt

Reads files from Windows share (Microsoft SMB/CIFS protocol) version 2 and 3.

The SMB2 protocol is implemented in the SMBJ library.

Due to the upgrade of the SMBJ library in CloverDX version 6.2, anonymous access using SMB protocol version 2 or 3 will no longer work unless your Samba server is configured to stop requiring message signing. If turning off message signing is not an option, you can create a user without a password to use in the URL as a workaround. See below for example URLs:
smb2://domain%3Buser@server/path/filename.txt
smb2://domain%3Buser:@server/path/filename.txt

Reading from input port

port:$0.FieldName:discrete

Each data record field from input port represents one particular data source.
port:$0.FieldName:source

Each data record field from an input port represents a URL to be loaded in and parsed.
port:$0.FieldName:stream

Input port field values are concatenated and processed as an input file(s); null values are replaced by the eof.

Using proxy in Readers

http:(direct:)//seznam.cz

Without proxy.
http:(proxy://user:password@212.93.193.82:443)//seznam.cz

Proxy setting for HTTP protocol.
ftp:(proxy://user:password@proxyserver:1234)//seznam.cz

Proxy setting for FTP protocol.
sftp:(proxy://66.11.122.193:443)//user:password@server/path/file.dat

Proxy setting for SFTP protocol.
s3:(proxy://user:password@66.11.122.193:443)//access_key_id:secret_access_key@s3.amazonaws.com/bucketname/filename*.dat

Proxy setting for S3 protocol.

Reading from dictionary

dict:keyName:discrete^[1]

Reads data from dictionary.
dict:keyName:source^[1]

Reads data from dictionary in the same way as the discrete processing type, but expects that the dictionary values are input file URLs. The data from this input passes to the Reader.

Sandbox resource as data source

A sandbox resource, whether it is a shared, local or partitioned sandbox, is specified in the graph under the fileURL attributes as a so called sandbox URL like this:

sandbox://data/path/to/file/file.dat

where data is a code for sandbox and path/to/file/file.dat is the path to the resource from the sandbox root. The URL is evaluated by CloverDX Server during graph execution and a component (reader or writer) obtains the opened stream from the Server. This may be a stream to a local file or to some other remote resource. Thus, a graph does not have to run on the node which has local access to the resource. There may be more sandbox resources used in the graph and each of them may be on a different node. In such cases, CloverDX Server would choose the node with the most local resources to minimize remote streams.

The sandbox URL has a specific use for parallel data processing. When the sandbox URL with the resource in a partitioned sandbox is used, that part of the graph/phase runs in parallel, according to the node allocation specified by the list of partitioned sandbox locations. Thus, each worker has its own local sandbox resource. CloverDX Server evaluates the sandbox URL on each worker and provides an open stream to a local resource to the component.