adding warehouse support (iceberg)

info/__init__.py

@@ -1,6 +1,6 @@
 __app_name__  = 'data-transport'
 __author__ = 'The Phi Technology'
-__version__= '2.2.6'
+__version__= '2.4.0'
 __email__  = "info@the-phi.com"
 __license__=f"""
 Copyright 2010 - 2024, Steve L. Nyemba
@@ -15,7 +15,9 @@ THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR I
 
 __whatsnew__=f"""version {__version__}, focuses on collaborative environments like jupyter-base servers (apache zeppelin; jupyter notebook, jupyterlab, jupyterhub)
 
-    1. simpler syntax to create readers/writers
+    1. support for apache iceberg data warehouse using spark
-    2. auth-file registry that can be referenced using a label
+    2. Improved ETL & performance
-    3. duckdb support
+    3. bug fixes: mongodb
+
+    
 """

transport/__init__.py

@@ -18,7 +18,7 @@ Source Code is available under MIT License:
 """
 import numpy as np
 
-from transport import sql, nosql, cloud, other
+from transport import sql, nosql, cloud, other, warehouse
 import pandas as pd
 import json
 import os
@@ -33,7 +33,7 @@ PROVIDERS = {}
 
 def init():
     global PROVIDERS
-    for _module in [cloud,sql,nosql,other] :
+    for _module in [cloud,sql,nosql,other,warehouse] :
         for _provider_name in dir(_module) :
             if _provider_name.startswith('__') or _provider_name == 'common':
                 continue

transport/providers/__init__.py

@@ -44,7 +44,8 @@ PGSQL	= POSTGRESQL
 
 AWS_S3  = 's3'
 RABBIT = RABBITMQ
-
+ICEBERG='iceberg'
+APACHE_ICEBERG = 'iceberg'
 
 # QLISTENER = 'qlistener'
     

transport/warehouse/__init__.py

@@ -0,0 +1,7 @@
+"""
+This namespace/package is intended to handle read/writes against data warehouse solutions like :
+    - apache iceberg
+    - clickhouse (...)
+"""
+
+from . import iceberg

transport/warehouse/iceberg.py

@@ -0,0 +1,98 @@
+from pyspark.sql import SparkSession
+import copy
+
+class Iceberg :
+    def __init__(self,**_args):
+        """
+        providing catalog meta information (you must get this from apache iceberg)
+        """
+        #
+        # @TODO:
+        #   Make arrangements for additional configuration elements 
+        #
+        self._session = SparkSession.builder.getOrCreate()
+        self._catalog = self._session.catalog
+        self._table = _args['table'] if 'table' in _args else None
+        
+        if 'catalog' in _args :
+            #
+            # Let us set the default catalog
+            self._catalog.setCurrentCatalog(_args['catalog'])
+            
+        else:
+            # No current catalog has been set ...
+            pass
+        if 'database' in _args :
+            self._database = _args['database']
+            self._catalog.setCurrentDatabase(self._database)
+        else:
+            #
+            # Should we set the default as the first one if available ?
+            #
+            pass
+        self._catalogName = self._catalog.currentCatalog()
+        self._databaseName = self._catalog.currentDatabase()
+    def meta (self,**_args) :
+        """
+        This function should return the schema of a table (only)
+        """
+        _schema = []
+        try:
+            _tableName = self._getPrefix(**_args) + f".{_args['table']}"
+            print (_tableName)
+            _tmp = self._session.table(_tableName).schema
+            _schema = _tmp.jsonValue()['fields']
+            for _item in _schema :
+                del _item['nullable'],_item['metadata']
+        except Exception as e:
+            
+            pass
+        return _schema
+    def _getPrefix (self,**_args):        
+        _catName = self._catalogName if 'catalog' not in _args else _args['catalog']
+        _datName = self._databaseName if 'database' not in _args else _args['database']
+        
+        return '.'.join([_catName,_datName])
+            
+    def has (self,**_args):
+        try:
+            _prefix = self._getPrefix(**_args)
+            if _prefix.endswith('.') :
+                return False
+            return _args['table'] in [_item.name for _item in self._catalog.listTables(_prefix)]
+        except Exception as e:
+            print (e)
+            return False
+    def apply(self,sql):
+        pass
+class Reader(Iceberg) :
+    def __init__(self,**_args):
+        super().__init__(**_args)
+    def read(self,**_args):
+        _table = self._table
+        _prefix = self._getPrefix(**_args)        
+        if 'table' in _args or _table:
+            _table = _args['table'] if 'table' in _args else _table
+            _table = _prefix + f'.{_table}'
+            return self._session.table(_table).toPandas()
+        else:
+            sql = _args['sql']
+            return self._session.sql(sql).toPandas()
+        pass
+class Writer (Iceberg):
+    """
+    Writing data to an Apache Iceberg data warehouse (using pyspark)
+    """
+    def __init__(self,**_args):
+        super().__init__(**_args)
+        self._mode = 'append'
+        self._table = None if 'table' not in _args else _args['table']
+    def write(self,_data,**_args):
+        _prefix = self._getPrefix(**_args)
+        if 'table' not in _args and not self._table :
+            raise Exception (f"Table Name should be specified for catalog/database {_prefix}")
+        rdd = self._session.createDataFrame(_data)
+        _mode = self._mode if 'mode' not in _args else _args['mode']
+        _table = self._table if 'table' not in _args else _args['table']
+        _table = f'{_prefix}.{_table}'
+        rdd.write.format('iceberg').mode(self._mode).save(_table)