Add hbase-write script

hbase-write.py

@@ -0,0 +1,141 @@
+#!/usr/bin/env python3
+#
+# Use happybase (https://github.com/python-happybase/happybase) to perform
+# a write/read test on a dedicated table for monitoring purposes.
+#
+# The table gets deleted if it exists, (re-)created and a write is done
+# to the newly created table.  Data is written and gets read back.
+# Afterwards the table gets deleted again.
+#
+# On success the script returns 0 otherwise 1
+#
+# Required environment vars are:
+#  HBASE_HOST
+#
+# Optional environment vars:
+#  HBASE_TABLE_NAME
+
+import happybase
+import os
+import sys
+
+required_env_vars = ["HBASE_HOST"]
+
+default_hbase_table_name = "monitoring_write_test"
+row_key = "monitoring_write_test".encode("utf-8")
+data = b'This is how a successful write looks like.'
+
+# Check env for required vars,
+# exit if not found
+def check_required_vars(env_vars):
+    for k in env_vars:
+        if None == os.getenv(k):
+            print("Required environment variable missing: " + k)
+            sys.exit(1)
+
+
+# Get a list of all tables
+def tables(conn):
+    tables = []
+    ts = conn.tables()
+    for t in ts:
+        tables.append(t.decode("utf-8"))
+
+    return tables
+
+# Print all tables
+def list_tables(tables):
+    for t in tables:
+        print(t)
+
+
+# Check if given table exists
+def table_exists(conn, table_name):
+    tablelist = tables(conn)
+
+    try:
+        x = tablelist.index(table_name)
+    except ValueError:
+        print("Table {:s} does not exist" .format(table_name))
+        return False
+    else:
+        print("Table {:s} exists" .format(table_name))
+        return True
+
+
+def create_table(conn, table_name):
+    print("Creating table: ", table_name)
+    conn.create_table(
+        hbase_table_name,
+        {'cf0': dict(max_versions=1, block_cache_enabled=False)}
+    )
+
+
+# Delete a table
+def delete_table(conn, table_name):
+    print("Deleting table: ", table_name)
+    conn.delete_table(hbase_table_name, disable=True)
+
+
+# Read data at row_key from table
+def read(conn, table_name, row_key):
+    print("Reading from table {:s} " .format(table_name))
+    table = conn.table(hbase_table_name)
+    row = table.row(row_key)
+    print("data: {:s}" .format(row[b'cf0:'].decode("utf-8")))
+
+
+# Read data from table
+def read_all(conn, table_name, row_key):
+    print("Reading from table {:s} " .format(table_name))
+    table = conn.table(hbase_table_name)
+
+    for key, data in table.rows([row_key]):
+        print(key, data)
+
+
+# Scan table
+def scan(conn, table_name):
+    print("Reading from table {:s} " .format(table_name))
+    table = conn.table(hbase_table_name)
+
+    for key, data in table.scan(row_prefix=b'row'):
+        print(key, data)
+
+
+# Write data at 'row_key' to table
+def write(conn, table_name, row_key, data):
+    print("Writing to table {:s} " .format(table_name))
+    table = conn.table(hbase_table_name)
+    table.put(row_key, {b'cf0:': data})
+
+
+# Delete data at 'row_key'
+def delete(conn, table_name, row_key):
+    row = table.delete(row_key)
+
+
+if __name__ == '__main__':
+
+    check_required_vars(required_env_vars)
+
+    hbase_host = os.getenv("HBASE_HOST")
+    hbase_table_name = os.getenv("HBASE_TABLE_NAME")
+
+    if not hbase_table_name:
+        hbase_table_name = default_hbase_table_name
+
+    try:
+        conn = happybase.Connection(hbase_host)
+    except:
+        print("Failed to connect to: {:s}" .format(hbase_host))
+        sys.exit(1)
+
+    if table_exists(conn, hbase_table_name):
+        delete_table(conn, hbase_table_name)
+
+    # Run a full test cycle
+    create_table(conn, hbase_table_name)
+    write(conn, hbase_table_name, row_key, data)
+    read(conn, hbase_table_name, row_key)
+    delete_table(conn, hbase_table_name)