simple-client


Simple Client

This demos shows how to use the bayeos.cli.SimpleClient class to connect to a BayEOS Server. The class implements basic functionalities with native python tpyes for read and write functions. There are no dependencies to external libraries.

Import of bayeos package

The SimpleClient class can be imported as any other python class.


In [1]:
from bayeos.cli import SimpleClient

We need an instance of it:


In [2]:
bayeos = SimpleClient()

Server Connection

Let us now open the connection to our freely available BayEOS Server and save the connection information in a encrypted file on our local disk. We can pick the connection information later on by an alias.


In [3]:
bayeos.connect(url="http://bayeos.bayceer.uni-bayreuth.de/BayEOS-Server/XMLServlet",user="gast",password="gast",save_as="guest@bayeos")


Open connection to http://bayeos.bayceer.uni-bayreuth.de/BayEOS-Server/XMLServlet as user gast
Out[3]:
True

A connection can be closed by calling disconnect()


In [4]:
bayeos.disconnect()


Connection closed
Out[4]:
True

Just call the connect() function with the parameter listConnections=True to list all available connection alias.


In [5]:
bayeos.connect(listConnections=True)


Alias               |URL                                                                             |User      
--------------------|--------------------------------------------------------------------------------|----------
root@bayeos         |https://bayeos.bayceer.uni-bayreuth.de/BayEOS-Server/XMLServlet                 |root      
root@localhost      |http://localhost:5532/XMLServlet                                                |root      
bayeos              |https://bayeos.bayceer.uni-bayreuth.de/BayEOS-Server/XMLServlet                 |bt220259  
me@bayeos           |https://bayeos.bayceer.uni-bayreuth.de/BayEOS-Server/XMLServlet                 |niessner  
guest@bayeos        |http://bayeos.bayceer.uni-bayreuth.de/BayEOS-Server/XMLServlet                  |gast      
myAlias             |http://bayconf.bayceer.uni-bayreuth.de/BayEOS-Server/XMLServlet                 |root      
Out[5]:
True

Use the alias to reopen the connection. The following call retrieves the alias in $HOME/.bayeos.pwd and decryptes it with a key stored in $HOME/.bayeos.pwd_key.


In [6]:
bayeos.connect(url="guest@bayeos")


Open connection to http://bayeos.bayceer.uni-bayreuth.de/BayEOS-Server/XMLServlet as user gast
Out[6]:
True

Basic Navigation

The basic navigation interface is loosely based on the UNIX file sytem navigation commands.

We can list the content of a working directory by calling the ls() function. The output shows the id, name, type, first and last result date of folders and series rendered as a table.


In [7]:
bayeos.ls()


Alle Messungen
None      |..
126232    |Dr. Hans-Frisch                                   |messung_ordner      |1884-01-26 17:20:00 |2020-03-02 14:50:00 
14333     |Micrometeorology Dept                             |messung_ordner      |1984-11-01 18:25:00 |2020-03-02 15:02:00 
117846    |Pivot Tabellen                                    |messung_ordner      |1970-01-01 00:00:00 |2020-01-01 00:00:00 
14325     |Steinkreuz                                        |messung_ordner      |1994-03-17 12:00:00 |2008-04-08 10:50:00 

Use the cd() function to change the current working directory. You need to pass in the folder id.


In [8]:
bayeos.cd(14333)


Alle Messungen/Micrometeorology Dept
83        |..
14473     |AWS Ecological Botanical Garden                   |messung_ordner      |1992-01-06 00:00:00 |2020-03-02 14:56:00 

Please call cd('..') to switch into the parent directory.


In [ ]:
bayeos.cd('..')

The pwd() function prints the current working directory path.


In [ ]:
bayeos.pwd()

Please close the connection before you shut down the kernel.


In [9]:
bayeos.disconnect()


Connection closed
Out[9]:
True

CRUD Operations

The SimpleClient provides methods to create, read, update and delete a series.

Import the package and open a new connection with write privileges.


In [11]:
from bayeos.cli import SimpleClient 
bayeos = SimpleClient()
bayeos.connect(url='myAlias')


Open connection to http://bayconf.bayceer.uni-bayreuth.de/BayEOS-Server/XMLServlet as user root
Out[11]:
True

Create series

To create three series and return the ids as a list we use pythons handy list comprehension functionality.


In [12]:
ids = [bayeos.createSeries("Dummy" + x) for x in ["A","B","C"] ]

Import some observation records as list of lists. The first column contains the observation time by convention.


In [13]:
from datetime import datetime, timedelta
now = datetime.utcnow()
past = now + timedelta(minutes=-10)
data = [[now,2.1,2.2,2.3],[past,1.1,1.2,1.3]]
bayeos.writeSeries(ids,data)


6 records imported.

Read values


In [14]:
(header, data) = bayeos.getSeries(ids,interval='today')

In [15]:
header


Out[15]:
['DummyA', 'DummyB', 'DummyC']

In [16]:
data


Out[16]:
[[datetime.datetime(2020, 3, 2, 13, 56, 15, tzinfo=<UTC>),
  1.100000023841858,
  1.2000000476837158,
  1.2999999523162842],
 [datetime.datetime(2020, 3, 2, 14, 6, 15, tzinfo=<UTC>),
  2.0999999046325684,
  2.200000047683716,
  2.299999952316284]]

Update values

You can call the writeSeries function with overwrite=True to update a value.


In [17]:
data = [[now,3.1,3.2,3.3]]
bayeos.writeSeries(ids,data,overwrite=True)
(header, data) = bayeos.getSeries(ids,interval='today')


3 records imported.

In [18]:
data


Out[18]:
[[datetime.datetime(2020, 3, 2, 13, 56, 15, tzinfo=<UTC>),
  1.100000023841858,
  1.2000000476837158,
  1.2999999523162842],
 [datetime.datetime(2020, 3, 2, 14, 6, 15, tzinfo=<UTC>),
  3.0999999046325684,
  3.200000047683716,
  3.299999952316284]]

Delete series

Drop all created series by id.


In [19]:
[bayeos.deleteSeries(x) for x in ids]


Out[19]:
[True, True, True]

Close the connection


In [ ]:
bayeos.disconnect()