SFTP/FTP Client

The SFTP/FTP Client origin reads files from a server using the Secure File Transfer Protocol (SFTP) or the File Transfer Protocol (FTP).

When you configure the SFTP/FTP Client origin, you specify the URL where the files reside on the remote server. You can specify whether to process files in subdirectories, a file name pattern, and the first file to process.

If the server requires authentication, configure the origin to use login credentials. If using the SFTP protocol, you can also configure the origin for strict host checking.

You can configure the origin to download files to an archive directory if the origin encounters errors while reading the files.

When the pipeline stops, the SFTP/FTP Client origin notes where it stops reading. When the pipeline starts again, the origin continues processing from where it stopped by default. You can reset the origin to process all requested files.

Read Order

The SFTP/FTP Client origin reads files in ascending order based on the last-modified timestamp. When the origin reads from a secondary location - not the directory where the files are created and written - the last-modified timestamp should be when the file is moved to the directory to be processed.
Tip: Avoid moving files using commands that preserve the existing timestamp, such as cp -p. Preserving the existing timestamp can be problematic in some cases, such as moving files across time zones.

When ordering based on timestamp, any files with the same timestamp are read in lexicographically ascending order based on the file names.

For example, when reading files with the log*.json file name pattern, the origin reads the following files in the following order:
File Name
Last Modified Timestamp
log-1.json
APR 24 2016 14:03:35
log-0054.json
APR 24 2016 14:05:03
log-0055.json 
APR 24 2016 14:45:11
log-2.json
APR 24 2016 14:45:11

First File for Processing

Configure a first file for processing when you want the SFTP/FTP Client origin to ignore one or more existing files in the directory.

When you define a first file to process, the origin starts processing with the specified file and continues processing files in the expected read order: files that match the file name pattern in ascending order based on the last-modified timestamp.

When you do not specify a first file, the origin processes the files in the directory that match the file name pattern, starting with the earliest file and continuing in ascending order.

For example, if you specify a first file with the last-modified timestamp of 6/01/2017 00:00:00, the origin starts processing with that file and ignores all older files in the directory.
Note: When you restart a stopped pipeline, the origin ignores this property. It starts where it left off regardless of the first file name unless you reset the origin.

Credentials

If the remote server requires authentication, configure the authentication method that the origin must use to log in to the remote server.

Configure one of the following authentication methods:
None
The SFTP or FTP server does not require authentication.
Password
The SFTP or FTP server requires authentication using a user name and password.
Private key
The SFTP server requires authentication using a private key file. Store the private key file in a local directory. For the SFTP protocol only.

If using the SFTP protocol, you can also configure the origin to use strict host checking. When enabled, the origin connects to the SFTP server only if the server is listed in the known hosts file stored in a local directory. The known hosts file contains the host keys for the approved SFTP servers.

Data Formats

The SFTP/FTP Client origin processes data differently based on the data format. SFTP/FTP Client processes the following types of data:

Avro
Generates a record for every Avro record.
You can use one of the following methods to specify the location of the Avro schema definition:
  • Message/Data Includes Schema - Use the schema in the file.
  • In Pipeline Configuration - Use the schema that you provide in the stage configuration.
  • Confluent Schema Registry - Retrieve the schema from Confluent Schema Registry. The Confluent Schema Registry is a distributed storage layer for Avro schemas. You can configure the origin to look up the schema in the Confluent Schema Registry by the schema ID or subject specified in the stage configuration.
Using a schema in the stage configuration or retrieving a schema from the Confluent Schema Registry overrides any schema that might be included in the file and can improve performance.
The origin reads files compressed by Avro-supported compression codecs without requiring additional configuration. To enable the origin to read files compressed by other codecs, use the compression format property in the stage.
Delimited
Generates a record for each delimited line. You can use the following delimited format types:
  • Default CSV - File that includes comma-separated values. Ignores empty lines in the file.
  • RFC4180 CSV - Comma-separated file that strictly follows RFC4180 guidelines.
  • MS Excel CSV - Microsoft Excel comma-separated file.
  • MySQL CSV - MySQL comma separated file.
  • Tab-Separated Values - File that includes tab-separated values.
  • Custom - File that uses user-defined delimiter, escape, and quote characters.
You can use a list or list-map root field type for delimited data, optionally including the header information when available.
You can also replace a string constant with null values.
When a record exceeds the user-defined maximum record length, the origin cannot continue processing data in the file. Records already processed from the file are passed to the pipeline. The behavior of the origin is then based on the error handling configured for the stage:
  • Discard - The origin continues processing with the next file, leaving the partially-processed file in the directory.
  • To Error - The origin continues processing with the next file. If a post-processing error directory is configured for the stage, the origin moves the partially-processed file to the error directory. Otherwise, it leaves the file in the directory.
  • Stop Pipeline - The origin stops the pipeline.
For more information about the root field types, see Delimited Data Root Field Type.
JSON
Generates a record for each JSON object. You can process JSON files that include multiple JSON objects or a single JSON array.
When an object exceeds the maximum object length defined for the origin, the origin cannot continue processing data in the file. Records already processed from the file are passed to the pipeline. The behavior of the origin is then based on the error handling configured for the stage:
  • Discard - The origin continues processing with the next file, leaving the partially-processed file in the directory.
  • To Error - The origin continues processing with the next file. If a post-processing error directory is configured for the stage, the origin moves the partially-processed file to the error directory. Otherwise, it leaves the file in the directory.
  • Stop Pipeline - The origin stops the pipeline.
Log
Generates a record for every log line.
When a line exceeds the user-defined maximum line length, the origin truncates longer lines.
You can include the processed log line as a field in the record. If the log line is truncated, and you request the log line in the record, the origin includes the truncated line.
You can define the log format or type to be read.
Protobuf
Generates a record for every protobuf message.
Protobuf messages must match the specified message type and be described in the descriptor file.
When the data for a record exceeds 1 MB, the origin cannot continue processing data in the file. The origin handles the file based on file error handling properties and continues reading the next file.
For information about generating the descriptor file, see Protobuf Data Format Prerequisites.
SDC Record
Generates a record for every record. Use to process records generated by a Data Collector pipeline using the SDC Record data format.
For error records, the origin provides the original record as read from the origin in the original pipeline, as well as error information that you can use to correct the record.
When processing error records, the origin expects the error file names and contents as generated by the original pipeline.
Text
Generates a record for each line of text or for each section of text based on a custom delimiter.
When a line or section exceeds the maximum line length defined for the origin, the origin truncates it. The origin adds a boolean field named Truncated to indicate if the line was truncated.
For more information about processing text with a custom delimiter, see Text Data Format with Custom Delimiters.
Whole File
Streams whole files from the origin system to the destination system. You can specify a transfer rate or use all available resources to perform the transfer.
The origin generates two fields: one for a file reference and one for file information. For more information, see Whole File Data Format.
XML
Generates records based on a user-defined delimiter element. Use an XML element directly under the root element or define a simplified XPath expression. If you do not define a delimiter element, the origin treats the XML file as a single record.
Generated records include XML attributes and namespace declarations as fields in the record by default. You can configure the stage to include them in the record as field attributes.
You can include XPath information for each parsed XML element and XML attribute in field attributes. This also places each namespace in an xmlns record header attribute.
Note: Field attributes and record header attributes are written to destination systems automatically only when you use the SDC RPC data format in destinations. For more information about working with field attributes and record header attributes, and how to include them in records, see Field Attributes and Record Header Attributes.
When a record exceeds the user-defined maximum record length, the origin cannot continue processing data in the file. Records already processed from the file are passed to the pipeline. The behavior of the origin is then based on the error handling configured for the stage:
  • Discard - The origin continues processing with the next file, leaving the partially-processed file in the directory.
  • To Error - The origin continues processing with the next file. If a post-processing error directory is configured for the stage, the origin moves the partially-processed file to the error directory. Otherwise, it leaves the file in the directory.
  • Stop Pipeline - The origin stops the pipeline.
Use the XML data format to process valid XML documents. For more information about XML processing, see XML Data Format and Data Processing.
Tip: If you want to process invalid XML documents, you can try using the text data format with custom delimiters. For more information, see Processing XML Data with Custom Delimiters.

Configuring an SFTP/FTP Client Origin

Configure an SFTP/FTP Client origin to read files from an SFTP or FTP server.

  1. In the Properties panel, on the General tab, configure the following properties:
    General Property Description
    Name Stage name.
    Description Optional description.
    On Record Error Error record handling for the stage:
    • Discard - Discards the record.
    • Send to Error - Sends the record to the pipeline for error handling.
    • Stop Pipeline - Stops the pipeline.
  2. On the SFTP/FTP tab, configure the following properties:
    SFTP/FTP Property Description
    Resource URL URL where the files reside on the remote server.
    For the SFTP protocol, use the following format:
    sftp://<host name>:<port number>/<path>
    For the FTP protocol, use the following format:
    ftp://<host name>:<port number>/<path> 

    You can omit the port number from the URL if the server uses the standard port number - 22 for SFTP or 21 for FTP.

    You can optionally include the user name to log in to the SFTP or FTP server in the URL. For example, for the FTP protocol, you can use the following format:

    ftp://<user name>:<password>@<host name>/<path>
    Note: If you enter a user name in the resource URL and configure password or private key authentication on the Credentials tab, the value entered in the URL takes precedence.
    Path Relative to User Home Directory Select if the path included in the resource URL is relative to the home directory of the user that logs in to the remote server.

    Applicable when you include a user name in the URL or when you configure password or private key authentication on the Credentials tab.

    Process Subdirectories Select to process files in all subdirectories of the specified path.
    File Name Pattern Glob-style pattern that defines the file names to process. You can use UNIX-style wildcards, such as * or ?.

    For example, the pattern ??a represents three-character file names which end with "a". The pattern *.txt represents file names of one or more characters ending with ".txt".

    You cannot use a tilde (~) or slash (/) in the pattern. You cannot use a period (.) at the beginning of the pattern. The origin treats a period as a literal in other spots in the pattern.

    If Process Subdirectories is selected, then the origin uses the same pattern to locate file names in the subdirectories. The origin does not use the pattern for subdirectory names.

    Default is *, which processes all files.

    First File to Process Name of the first file to process when you start the pipeline. Use a name that uses the file name pattern. Leave empty to read all files in the directory with the specified naming convention.

    When you enter a file name, the origin starts processing with the specified file.

    When you restart a stopped pipeline, the origin ignores this property. It starts where it left off regardless of the first file name unless you reset the origin.
    Max Batch Size (records) Maximum number of records to include in a batch and send through the pipeline at one time.
    Batch Wait Time (ms) Number of milliseconds to wait before sending a partial or empty batch.
  3. On the Credentials tab, configure the following properties:
    Credentials Property Description
    Authentication Method Authentication method to use to log in to the remote server:
    • None - The remote server does not require authentication.
    • Password - The remote server requires authentication using a user name and password.
    • Private key - The SFTP server requires authentication using a private key file.

    Default is None.

    Username User name to log in to the remote server. Used for password and private key authentication.
    Password Password to log in to the remote server. Used for password authentication.
    Tip: To secure sensitive information such as usernames and passwords, you can use runtime resources or Hashicorp Vault secrets. For more information, see Using Runtime Resources or Accessing Hashicorp Vault Secrets.
    Private Key File Full path to the local private key file used to log in to the remote server. Used for private key authentication.
    Private Key Passphrase Passphrase used to open the private key file. Used for private key authentication if the private key is protected with a passphrase.
    Strict Host Checking Specifies whether to check that the SFTP server is listed in the known hosts file. When enabled, the origin connects to the server only if the server is listed in the known hosts file.

    For the SFTP protocol only.

    Known Hosts File Full path to the local known hosts file. Required if strict host checking is selected.

    For the SFTP protocol only.

  4. On the Error Handling tab, configure the following properties:
    Error Handling Property Description
    Archive on Error Specifies whether to download and archive files to a local directory if the origin encounters errors while reading the file.
    Archive Directory Local directory to archive the files.
  5. On the Data Format tab, configure the following property:
    Data Format Property Description
    Data Format Data format for source files. Use one of the following formats:
    • Avro
    • Delimited
    • JSON
    • Log
    • Protobuf
    • SDC Record
    • Text
    • Whole File
    • XML
  6. For Avro data, on the Data Format tab, configure the following properties:
    Avro Property Description
    Avro Schema Location Location of the Avro schema definition to use when processing data:
    • Message/Data Includes Schema - Use the schema in the file.
    • In Pipeline Configuration - Use the schema provided in the stage configuration.
    • Confluent Schema Registry - Retrieve the schema from the Confluent Schema Registry.

    Using a schema in the stage configuration or in the Confluent Schema Registry can improve performance.

    Avro Schema Avro schema definition used to process the data. Overrides any existing schema definitions associated with the data.

    You can optionally use the runtime:loadResource function to use a schema definition stored in a runtime resource file.

    Schema Registry URLs Confluent Schema Registry URLs used to look up the schema. To add a URL, click Add. Use the following format to enter the URL:
    http://<host name>:<port number>
    Lookup Schema By Method used to look up the schema in the Confluent Schema Registry:
    • Subject - Look up the specified Avro schema subject.
    • Schema ID - Look up the specified Avro schema ID.
    Overrides any existing schema definitions associated with the data.
    Schema Subject Avro schema subject to look up in the Confluent Schema Registry.

    If the specified subject has multiple schema versions, the origin uses the latest schema version for that subject. To use an older version, find the corresponding schema ID, and then set the Look Up Schema By property to Schema ID.

    Schema ID Avro schema ID to look up in the Confluent Schema Registry.
  7. For delimited data, on the Data Format tab, configure the following properties:
    Delimited Property Description
    Compression Format The compression format of the files:
    • None - Processes only uncompressed files.
    • Compressed File - Processes files compressed by the supported compression formats.
    • Archive - Processes files archived by the supported archive formats.
    • Compressed Archive - Processes files archived and compressed by the supported archive and compression formats.
    File Name Pattern within Compressed Directory File name pattern that represents the files to process within the compressed directory. You can use UNIX-style wildcards, such as an asterisk or question mark. For example, *.json.

    Default is *, which processes all files.

    Delimiter Format Type Delimiter format type. Use one of the following options:
    • Default CSV - File that includes comma-separated values. Ignores empty lines in the file.
    • RFC4180 CSV - Comma-separated file that strictly follows RFC4180 guidelines.
    • MS Excel CSV - Microsoft Excel comma-separated file.
    • MySQL CSV - MySQL comma separated file.
    • Tab-Separated Values - File that includes tab-separated values.
    • Custom - File that uses user-defined delimiter, escape, and quote characters.
    Header Line Indicates whether a file contains a header line, and whether to use the header line.
    Max Record Length (chars) Maximum length of a record in characters. Longer records are not read.

    This property can be limited by the Data Collector parser buffer size. For more information, see Maximum Record Size.

    Delimiter Character Delimiter character for a custom delimiter format. Select one of the available options or use Other to enter a custom character.

    You can enter a Unicode control character using the format \uNNNN, where ‚ÄčN is a hexadecimal digit from the numbers 0-9 or the letters A-F. For example, enter \u0000 to use the null character as the delimiter or \u2028 to use a line separator as the delimiter.

    Default is the pipe character ( | ).

    Escape Character Escape character for a custom file type.
    Quote Character Quote character for a custom file type.
    Root Field Type Root field type to use:
    • List-Map - Generates an indexed list of data. Enables you to use standard functions to process data. Use for new pipelines.
    • List - Generates a record with an indexed list with a map for header and value. Requires the use of delimited data functions to process data. Use only to maintain pipelines created before 1.1.0.
    Lines to Skip Lines to skip before reading data.
    Parse NULLs Replaces the specified string constant with null values.
    NULL Constant String constant to replace with null values.
    Charset Character encoding of the files to be processed.
    Ignore Ctrl Characters Removes all ASCII control characters except for the tab, line feed, and carriage return characters.
  8. For JSON data, on the Data Format tab, configure the following properties:
    JSON Property Description
    Compression Format The compression format of the files:
    • None - Processes only uncompressed files.
    • Compressed File - Processes files compressed by the supported compression formats.
    • Archive - Processes files archived by the supported archive formats.
    • Compressed Archive - Processes files archived and compressed by the supported archive and compression formats.
    File Name Pattern within Compressed Directory File name pattern that represents the files to process within the compressed directory. You can use UNIX-style wildcards, such as an asterisk or question mark. For example, *.json.

    Default is *, which processes all files.

    JSON Content Type of JSON content. Use one of the following options:
    • Array of Objects
    • Multiple Objects
    Maximum Object Length (chars) Maximum number of characters in a JSON object.

    Longer objects are diverted to the pipeline for error handling.

    This property can be limited by the Data Collector parser buffer size. For more information, see Maximum Record Size.

    Charset Character encoding of the files to be processed.
    Ignore Ctrl Characters Removes all ASCII control characters except for the tab, line feed, and carriage return characters.
  9. For log data, on the Data Format tab, configure the following properties:
    Log Property Description
    Compression Format The compression format of the files:
    • None - Processes only uncompressed files.
    • Compressed File - Processes files compressed by the supported compression formats.
    • Archive - Processes files archived by the supported archive formats.
    • Compressed Archive - Processes files archived and compressed by the supported archive and compression formats.
    File Name Pattern within Compressed Directory File name pattern that represents the files to process within the compressed directory. You can use UNIX-style wildcards, such as an asterisk or question mark. For example, *.json.

    Default is *, which processes all files.

    Log Format Format of the log files. Use one of the following options:
    • Common Log Format
    • Combined Log Format
    • Apache Error Log Format
    • Apache Access Log Custom Format
    • Regular Expression
    • Grok Pattern
    • Log4j
    Max Line Length Maximum length of a log line. The origin truncates longer lines.

    This property can be limited by the Data Collector parser buffer size. For more information, see Maximum Record Size.

    Retain Original Line Determines how to treat the original log line. Select to include the original log line as a field in the resulting record.

    By default, the original line is discarded.

    Charset Character encoding of the files to be processed.
    Ignore Ctrl Characters Removes all ASCII control characters except for the tab, line feed, and carriage return characters.
    • When you select Apache Access Log Custom Format, use Apache log format strings to define the Custom Log Format.
    • When you select Regular Expression, enter the regular expression that describes the log format, and then map the fields that you want to include to each regular expression group.
    • When you select Grok Pattern, you can use the Grok Pattern Definition field to define custom grok patterns. You can define a pattern on each line.

      In the Grok Pattern field, enter the pattern to use to parse the log. You can use a predefined grok patterns or create a custom grok pattern using patterns defined in Grok Pattern Definition.

      For more information about defining grok patterns and supported grok patterns, see Defining Grok Patterns.

    • When you select Log4j, define the following properties:
      Log4j Property Description
      On Parse Error Determines how to handle information that cannot be parsed:
      • Skip and Log Error - Skips reading the line and logs a stage error.
      • Skip, No Error - Skips reading the line and does not log an error.
      • Include as Stack Trace - Includes information that cannot be parsed as a stack trace to the previously-read log line. The information is added to the message field for the last valid log line.
      Use Custom Log Format Allows you to define a custom log format.
      Custom Format Use log4j variables to define a custom log format.
  10. For protobuf data, on the Data Format tab, configure the following properties:
    Protobuf Property Description
    Compression Format The compression format of the files:
    • None - Processes only uncompressed files.
    • Compressed File - Processes files compressed by the supported compression formats.
    • Archive - Processes files archived by the supported archive formats.
    • Compressed Archive - Processes files archived and compressed by the supported archive and compression formats.
    File Name Pattern within Compressed Directory File name pattern that represents the files to process within the compressed directory. You can use UNIX-style wildcards, such as an asterisk or question mark. For example, *.json.

    Default is *, which processes all files.

    Protobuf Descriptor File Descriptor file (.desc) to use. The descriptor file must be in the Data Collector resources directory, $SDC_RESOURCES.

    For more information about environment variables, see Data Collector Environment Configuration. For information about generating the descriptor file, see Protobuf Data Format Prerequisites.

    Message Type The fully-qualified name for the message type to use when reading data.

    Use the following format: <package name>.<message type>.

    Use a message type defined in the descriptor file.
    Delimited Messages Indicates if a file might include more than one protobuf message.
  11. For SDC Record data, on the Data Format tab, configure the following properties:
    SDC Record Property Description
    Compression Format The compression format of the files:
    • None - Processes only uncompressed files.
    • Compressed File - Processes files compressed by the supported compression formats.
    • Archive - Processes files archived by the supported archive formats.
    • Compressed Archive - Processes files archived and compressed by the supported archive and compression formats.
    File Name Pattern within Compressed Directory File name pattern that represents the files to process within the compressed directory. You can use UNIX-style wildcards, such as an asterisk or question mark. For example, *.json.

    Default is *, which processes all files.

  12. For text data, on the Data Format tab, configure the following properties:
    Text Property Description
    Compression Format The compression format of the files:
    • None - Processes only uncompressed files.
    • Compressed File - Processes files compressed by the supported compression formats.
    • Archive - Processes files archived by the supported archive formats.
    • Compressed Archive - Processes files archived and compressed by the supported archive and compression formats.
    File Name Pattern within Compressed Directory File name pattern that represents the files to process within the compressed directory. You can use UNIX-style wildcards, such as an asterisk or question mark. For example, *.json.

    Default is *, which processes all files.

    Max Line Length Maximum number of characters allowed for a line. Longer lines are truncated.

    Adds a boolean field to the record to indicate if it was truncated. The field name is Truncated.

    This property can be limited by the Data Collector parser buffer size. For more information, see Maximum Record Size.

    Use Custom Delimiter Uses custom delimiters to define records instead of line breaks.
    Custom Delimiter One or more characters to use to define records.
    Include Custom Delimiter Includes delimiter characters in the record.
    Charset Character encoding of the files to be processed.
    Ignore Ctrl Characters Removes all ASCII control characters except for the tab, line feed, and carriage return characters.
  13. For whole files on the Data Format tab, configure the following property:
    Whole File Property Description
    Buffer Size (bytes) Size of the buffer to use to transfer data.
    Rate per Second Transfer rate to use.

    Enter a number to specify a rate in bytes per second. Use an expression to specify a rate that uses a different unit of measure per second, e.g. ${5 * MB}. Use -1 to opt out of this property.

    By default, the origin does not use a transfer rate.

  14. For XML data, on the XML tab, configure the following properties:
    XML Property Description
    Compression Format The compression format of the files:
    • None - Processes only uncompressed files.
    • Compressed File - Processes files compressed by the supported compression formats.
    • Archive - Processes files archived by the supported archive formats.
    • Compressed Archive - Processes files archived and compressed by the supported archive and compression formats.
    Delimiter Element
    Delimiter to use to generate records. Omit a delimiter to treat the entire XML document as one record. Use one of the following:
    • An XML element directly under the root element.

      Use the XML element name without surrounding angle brackets ( < > ) . For example, msg instead of <msg>.

    • A simplified XPath expression that specifies the data to use.

      Use a simplified XPath expression to access data deeper in the XML document or data that requires a more complex access method.

      For more information about valid syntax, see Simplified XPath Syntax.

    Include Field XPaths Includes the XPath to each parsed XML element and XML attribute in field attributes. Also includes each namespace in an xmlns record header attribute.

    When not selected, this information is not included in the record. By default, the property is not selected.

    Note: Field attributes and record header attributes are written to destination systems automatically only when you use the SDC RPC data format in destinations. For more information about working with field attributes and record header attributes, and how to include them in records, see Field Attributes and Record Header Attributes.
    Namespaces Namespace prefix and URI to use when parsing the XML document. Define namespaces when the XML element being used includes a namespace prefix or when the XPath expression includes namespaces.

    For information about using namespaces with an XML element, see Using XML Elements with Namespaces.

    For information about using namespaces with XPath expressions, see Using XPath Expressions with Namespaces.

    Use the Add icon to add additional namespaces.

    Output Field Attributes Includes XML attributes and namespace declarations in the record as field attributes. When not selected, XML attributes and namespace declarations are included in the record as fields.
    Note: Field attributes are automatically included in records written to destination systems only when you use the SDC RPC data format in the destination. For more information about working with field attributes, see Field Attributes.

    By default, the property is not selected.

    Max Record Length (chars)

    The maximum number of characters in a record. Longer records are diverted to the pipeline for error handling.

    This property can be limited by the Data Collector parser buffer size. For more information, see Maximum Record Size.

    Charset Character encoding of the files to be processed.
    Ignore Ctrl Characters Removes all ASCII control characters except for the tab, line feed, and carriage return characters.