OpenStack Swift Object Store - Technical Preview - Import - Cloud

Talend Cloud Data Catalog Bridges

author
Talend Documentation Team
EnrichVersion
Cloud
EnrichProdName
Talend Cloud
EnrichPlatform
Talend Data Catalog

Bridge Specifications

Vendor OpenStack
Tool Name Swift Object Store
Tool Version 1.0
Tool Web Site https://www.openstack.org/software/releases/queens/components/swift
Supported Methodology [File System] Multi-Model, Data Store (NoSQL / Hierarchical) via REST API
Data Profiling
Remote Repository Browsing for Model Selection
Multi-Model Harvesting
Incremental Harvesting

SPECIFICATIONS
Tool: OpenStack / Swift Object Store version 1.0 via REST API
See https://www.openstack.org/software/releases/queens/components/swift
Metadata: [File System] Multi-Model, Data Store (NoSQL / Hierarchical)
Component: OpenStackSwift version 11.0.0

OVERVIEW
This bridge crawls a data lake implemented on a OpenStack Swift to detect (reverse engineer) metadata from all the data files (for data catalog purpose).

REQUIREMENTS

SUPPORTED FILES

This bridge supports the following file formats:
- Delimited (Flat) files such as CSV (see details below)
- Positional (Fixed Length) files typically from mainframe (see details below)
- COBOL COPYBOOK files typically from mainframe (see details below)
- Open Office Excel XML .XSLX (see details below)
- W3C XML
- JSON (JavaScript Object Notation)
- Apache Avro
- Apache Parquet
- Apache ORC

as well as the compressed versions of the above formats:
- ZIP (as a compression format, not as archive format)
- BZIP
- GZIP
- LZ4
- Snappy (as standard Snappy format, not as Hadoop native Snappy format)

DELIMITED FILES

This bridge detects (reverse engineer) the metadata from a data file of type Delimited File (also known as Flat File).
The detection of such Delimited File is not based on file extensions (such as .CSV, .PSV) but rather by sampling the file content.

The bridge can detect a header row, and use it to create the field name, otherwise generic filed names are created.

The bridge samples up to 1000 rows in order to automatically detect the field separators which by default include:
', (comma)' , '; (semicolon)', ': (colon)', '\t (tab)', '| (pipe)', '0x1 (ctrl+A)'
More separators can be added in the auto detection process (including double characters), see the Miscellaneous parameter.

During the sampling, the bridge also detects the file data types, such as DATE, NUMBER, STRING.

POSITIONAL FILES

This bridge creates metadata for data files of type Positional File (also known as Fixed Length File).
Such metadata cannot be automatically detected (reverse engineered) by sampling the data files (e.g. customers.dat or even just customers with no extension).
Therefore, this bridge imports a 'Positional File Definition' file which must be with extension .positional_file_definition format file
(e.g. customers.dat.positional_file_definition format file will create the metadata of a file named file customers with the fields defined inside)
This is the equivalent of a RDBMS DDL for positional files. With such a long extension, this data definition file can coexist with the actual data files in the each file system directory containing them.

The 'Positional File Definition' file format is defined as follows:
- Format file must start with the following header:
column name, position, width, data type, comment
- All positions must be unique and greater than or equal to 1.
a,1
b,5
- The file format is invalid when some columns have positions and others don't.
a,1
b,
c,5
- When all columns do not have positions but have widths the application assumes that columns are ordered and calculates positions based on widths.
a,,4 -> a,1,4
b,,25 -> b,5,25
- When the position is present the application uses widths for documentation only.
a,1,4
b,5,25
- Types and comments are used as documentation only.
a,1,4,int
b,5,25,char[25],identifier

COBOL COPYBOOK FILES

This bridge can only import the COBOL COPYBOOK files (which contain the data definitions), therefore does not detect (reverse engineer) metadata from actual COBOL data files.
The detection of such COBOL COPYBOOK File is not based on file extensions (such as .CPY) but rather by sampling the file content.

This bridges creates a 'Physical Hierarchical Model' which reflects a truly flat, byte-position defined, record structure, which is useful for stitching to the DI/ETL processes. Therefore, the physical model has all the physical elements required to define a flat record, which is ONE table with all the elements (including multiple columns for OCCURS elements when the proper bridge parameter is set).

Note that this bridge does not currently support the COPY verb, and reports a parsing error at the line and position at which the COPY statement begins. In order to import Copybooks with the Copy Statement, create an expanded Copybook file with the included sections already in place (replacing the COPY verb). Most COBOL compilers have the option to output only the preprocessed Copybooks with the COPY and REPLACE statements expanded.

FREQUENTLY ASKED QUESTIONS
Q: Why is the default start column '6' (six) and the default end column '72' (seventy-two)?
A: The bridge parser counts columns starting at 0 (zero), rather than 1 (one). Thus, the defaults leave the standard first six columns for line numbers, next column for comment indicators, and last 8 columns (out of 80) for additional line comment information.

EXCEL (XLSX) FILES

This bridge detects (reverse engineer) the metadata from a data file of type Excel XML format (XLSX).
The detection of such Excel File is based on file extension .XLSX.

The bridge can detect a header row, and use it to create the field name, otherwise generic filed names are created.

The bridge samples up to 1000 rows to detect the file data types, such as DATE, NUMBER, STRING.

If an Excel file has multiple sheets, each sheet is imported as the equivalent of a file/table with the same sheet name.

The bridge uses the machine's local to read files and allows you to specify the character set encoding files use.

LIMITATIONS
Refer to the current general known limitations at http://metaintegration.com/Products/MIMB/MIMBKnownLimitations.html or bundled in Documentation/ReadMe/MIMBKnownLimitations.html

SUPPORT
Provide a trouble shooting package with:
- the debug log (can be set in the UI or in conf/conf.properties with MIR_LOG_LEVEL=6)
- the metadata backup if available (can be set in the Miscellaneous parameter with option -backup)


Bridge Parameters

Parameter Name Description Type Values Default Scope
REST Endpoint: Your REST Endpoint to sign programmatic requests to the service. STRING      
Auth V1 Endpoint: Your Auth V1 Endpoint to authenticate the bridge. STRING      
User Username STRING      
Password Password PASSWORD      
Container CONTAINER name. STRING      
Miscellaneous INTRODUCTION
Specify miscellaneous options starting with a dash and optionally followed by parameters, e.g.
-connection.cast MyDatabase1="SQL Server"
Some options can be used multiple times if applicable, e.g.
-connection.rename NewConnection1=OldConnection1 -connection.rename NewConnection2=OldConnection2;
As the list of options can become a long string, it is possible to load it from a file which must be located in ${MODEL_BRIDGE_HOME}\data\MIMB\parameters and have the extension .txt. In such case, all options must be defined within that file as the only value of this parameter, e.g.
ETL/Miscellaneous.txt

JAVA ENVIRONMENT OPTIONS
-m <Java Memory's maximum size>
1G by default on 64bits JRE or as set in conf/conf.properties, e.g.
-m 8G
-m 8000M

-j <Java Runtime Environment command line options>
This option must be the last one in the Miscellaneous parameter as all the text after -j is passed "as is" to the JRE, e.g.
-j -Dname=value -Xms1G
The following option must be set when a proxy is used to access internet (this is critical to access https://repo.maven.apache.org/maven2/ (and exceptionally a few other tool sites) in order to download the necessary third party software libraries.
-j -Dhttp.proxyHost=127.0.0.1 -Dhttp.proxyPort=3128 -Dhttps.proxyHost=127.0.0.1 -Dhttps.proxyPort=3128 -Dhttp.proxyUser=user -Dhttp.proxyPassword=pass -Dhttps.proxyUser=user -Dhttps.proxyPassword=pass

-jre <Java Runtime Environment full path name>
It can be an absolute path to javaw.exe on Windows or a link/script path on Linux, e.g.
-jre "c:\Program Files\Java\jre1.8.0_211\bin\javaw.exe"

-v <Environment variable value>
None by default, e.g.
-v var1=value1 -v var2="value2 with spaces"

MODEL IMPORT OPTIONS
-model.name <model name>
Override the model name, e.g.
-model.name "My Model Name"

-prescript <script name>
The script must be located in the bin directory, and have .bat or .sh extension.
The script path must not include any parent directory symbol (..).
The script should return exit code 0 to indicate success, or another value to indicate failure.
For example:
-prescript "script.bat arg1 arg2"

-cache.clear
Clears the cache before the import, and therefore will run a full import without incremental harvesting.
Warning: this is a system option managed by the application calling the bridge and should not be set by users.

-backup <directory>
Full path of an empty directory to save the metadata input files for further troubleshooting.

DATA CONNECTION OPTIONS
Data Connections are produced by the import bridges typically from ETL/DI and BI tools to refer to the source and target data stores they use. These data connections are then used by metadata management tools to connect them (metadata stitching) to their actual data stores (e.g. databases, file system, etc.) in order to produce the full end to end data flow lineage and impact analysis. The name of each data connection is unique by import model. The data connection names used within DI/BI design tools are used when possible, otherwise connection names are generated to be short but meaningful such as the database / schema name, the file system path, or Uniform Resource Identifier (URI). The following options allows to manipulate connections. These options replaces the legacy options -c, -cd, and -cs.

-connection.cast ConnectionName=ConnectionType
Casts a generic database connection (e.g. ODBC/JDBC) to a precise database type (e.g. ORACLE) for SQL Parsing, e.g.
-connection.cast "My Database"="SQL SERVER".
The list of supported data store connection types includes:
ACCESS
CASSANDRA
DB2
DENODO
HIVE
MYSQL
NETEZZA
ORACLE
POSTGRESQL
PRESTO
REDSHIFT
SALESFORCE
SAP HANA
SNOWFLAKE
SQL SERVER
SYBASE
TERADATA
VECTORWISE
VERTICA

-connection.rename OldConnection=NewConnection
Renames an existing connection to a new name, e.g.
-connection.rename OldConnectionName=NewConnectionName
Multiple existing database connections can be renamed and merged into one new database connection, e.g.
-connection.rename MySchema1=MyDatabase -connection.rename MySchema2=MyDatabase

-connection.split oldConnection.Schema1=newConnection
Splits a database connection into one or multiple database connections.
A single database connection can be split into one connection per schema, e.g.
-connection.split MyDatabase
All database connections can be split into one connection per schema, e.g.
-connection.split *
A database connection can be explicitly split creating a new database connection by appending a schema name to a database, e.g.
-connection.split MyDatabase.schema1=MySchema1

-connection.map DestinationPath=SourcePath
Maps a source path to destination path. This is useful for file system connections when different paths points to the same object (directory or file).
On Hadoop, a process can write into a CSV file specified with the HDFS full path, but another process reads from a HIVE table implemented (external) by the same file specified using a relative path with default file name and extension, e.g.
-connection.map hdfs://host:8020/users/user1/folder/file.csv=/user1/folder
On Linux, a given directory (or file) like /data can be referred to by multiple symbolic links like /users/john and /users/paul, e.g.
-connection.map /users/John=/data -connection.map /users/paul=/data
On Windows, a given directory like C:\data can be referred to by multiple network drives like M: and N:, e.g.
-connection.map M:\=C:\data -connection.map N:\=C:\data

-pppd
Create the connections and connection data sets in DI/ETL design models. This feature should only be used when intending to export to another DI/ETL tool.

FILE SYSTEM OPTIONS
-file.encoding <Encoding value>
Uses the provided encoding value to read the text files (e.f. delimited and fixed width).
The supported languages are listed below with the actual encoding value between parentheses at the end of each line, e.g.
-file.encoding shift_jis

Central and Eastern European (iso-8859-2)
Central and Eastern European (windows-1250)
Chinese Traditional (big5)
Chinese Simplified (GB18030)
Chinese Simplified (GB2312)
Cyrillic (iso-8859-5)
Cyrillic (windows-1251)
DOS (ibm-850)
Greek (iso-8859-7)
Greek (windows-1253)
Hebrew (iso-8859-8)
Hebrew (windows-1255)
Japanese (shift_jis)
Korean (ks_c_5601-1987)
Thai (TIS620)
Thai (windows-874)
Turkish (iso-8859-9)
Turkish (windows-1254)
UTF 8 (utf-8)
UTF 16 (utf-16)
Western European (iso-8859-1)
Western European (iso-8859-15)
Western European (windows-1252)
Locale encoding
No encoding conversion

-tps <Processing Thread Pool Size's maximum count>
By default 1, for e.g.
-tps 10

-tl <Processing Time Limit duration>
No limits by default. Time can be specified in seconds, minutes, or hours, e.g.
-tl 3600s
-tl 60m
-tl 1h

-fl <Processing File Limit count>
No limits by default, e.g.
-fl 100

-hadoop <Hadoop configuration options>
None by default, e.g.
-hadoop key1=val1;key2=val2

-fresh.partition.models
Use to import latest modified files when processing partitions defined in Partitioned directories parameter.

-subst <path> <new path>
Use to associate a root path part with a drive or another path, e.g.
-subst K: C:/test

-skip.download
Use to disable dependencies downloading and use only download cache

-disable.partitions.autodetection
Use this option to disable automatic partitions detection(when "Partition directories" option is empty)

DELIMITED FILE OPTIONS
-delimited.no_header
Delimited File's header by default, bridge automatically tries to detect headers while processing csv files(basing on header columns types), use this option to disable headers import(f.e. to hide sensitive data)

-delimited.top_rows_skip <number>
Delimited file's number of rows to skip while processing (0 by default), e.g.
-delimited.top_rows_skip 1

-delimited.extra_separators <comma separated separators>
Delimited file's extra delimiters (separators by default are ), e.g.
-delimited.extra_separators ~,||,|~

PARQUET FILE OPTIONS
-parquet.compressed.max.size=<value>
Ignore parquet archives with size bigger then defined with this option value (Default value is 10 000 000 bytes), e.g.
-parquet.compressed.max.size=10000000
STRING      

 

Bridge Mapping

Meta Integration Repository (MIR)
Metamodel
(based on the OMG CWM standard)
"OpenStack Swift Object Store - New Beta Bridge"
Metamodel
File System (File)
Mapping Comments
     
Attribute Array Elementary Item, Field, Attribute, Array Field, Elementary Item, Fixed Width Field, Partition Field  
Name Name  
Position Position, Offset  
Class Array Element, Group Item, Array Group Item, Array Object, Element, Object, Sheet  
Name Name  
PropertyElementTypeScope UDPs  
Name Name  
Scope Scope  
PropertyType UDP  
DataType Data Type  
DesignLevel Design Level  
Name Name  
Position Position  
StoreModel Cobol File, Parquet File, Delimited File, Avro File, Json File, Collection, Orc File, Xml File, Excel File, File, Fixed Width File  
Name Name  
TypeValue Condition Name  
Name Name  
Value Value