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What is the best way to view the weblog? - Knowledgebase / General ALMA Queries - ALMA Science

What is the best way to view the weblog?

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For Mac OS and linux users the recommended internet browser to use to view pipeline weblogs is Firefox. Since 2021 weblogs made by the ALMA pipeline under  CASA 6.2.1-7 are also viewable with Chrome and Safari browsers, with some limitations on functionality.  

 Irrespective of the browser used, default security settings will often prevent full utilization of the weblog when directly opening it in your file system with a browser. To avoid these problems the recommended method to view the weblog is to use the CASA pipeline task h_weblog().  Please see case 1 below for instructions.  You can also view them through a local http server as described in case 2. 

For weblogs generated with older pipeline versions (e.g. < CASA 5.6.1) Firefox remains the advised browser to use.  

Please also check the ALMA Pipeline Known Issues page for more information.

Weblog interface errors can include:

  •  not opening or loading linked files, the 'by topic' or 'by task' pages, sub-plots and sub-pages - due to an inability to find the correct reference html page links. 
  • problems producing all plots or the radio direction buttons and side bar links. 
  • the index page open s correctly, but clicking to navigate further within the weblog gives an error page displayed, reading e.g.: "Error: cannot load content" or "Error loading file:///<path to the weblog>:0 error", dependent on the Pipeline version. These errors are due to browser security, which prevents the javascript within the weblog from displaying requested content.

Within the ALMA 2021 Pipeline (2021.2.0.128, CASA 6.2.1-7) and thereafter, the error page will indicate the best solutions in order to allow full viewing functionality of the weblog. These solutions are explained below and are also suitable for viewing weblogs from older ALMA Pipeline versions using <= CASA 6.1.1-15.  

How to open weblog with h_weblog or python3:

1) Use h_weblog() within a local CASA session:

From inside a CASA session, navigate to the root of the untarred weblog directory, e.g., pipeline-procedure_hifa_calimage, and run h_weblog. This command will serve the weblog via HTTP and launch a browser (in your default selected browser) connecting to the weblog. The weblog URL is also printed to the CASA logger, should you need to navigate to the weblog manually, or using a different brower. The URL to access is highlighted in the example CASA logger output below.

CASA <1>: h_weblog()

2020-07-30 12:57:20       INFO     h_weblog::::casa            #################################
2020-07-30 12:57:20       INFO     h_weblog::::casa            ##### Begin Task: h_weblog            ######
2020-07-30 12:57:20       INFO     h_weblog::::casa            h_weblog( pipelinemode='automatic', relpath='')
2020-07-30 12:57:20       INFO     h_weblog::pipeline::casa            Found weblogs at: 
2020-07-30 12:57:20       INFO     h_weblog::pipeline::casa+                     main/pipeline=procedure_hifa_calimage/html/t1-1.html
2020-07-30 12:57:20       INFO     h_weblog::pipeline::casa            Using existing HTTP server at 127.0.0.1 port 30000 ...
2020-07-30 12:57:20       INFO     h_weblog::pipeline::casa            Opening http://127.0.0.1:30000/main/pipeline=procedure_hifa_calimage/html/t1-1.htm
2020-07-30 12:57:20       INFO     h_weblog::::casa           Result h_weblog: None
2020-07-30 12:57:20       INFO     h_weblog::::casa           Task h_weblog complete. Start time: 2020-07-30 08:57:19.880720 End time: 2020-07-30 08:57:20.064263
2020-07-30 12:57:20       INFO     h_weblog::::casa           ##### End Task: h_weblog               ######

2020-07-30 12:57:20       INFO     h_weblog::::casa           #################################


For security, the weblog HTTP server is only accessible from the same computer as the CASA session. To view the weblog from another computer you must forward the port using SSH. For example, to access the weblog hosted on a remote machine called remotepc, where the CASA log reports the weblog is available at port 30000, execute:

ssh -L 30000:localhost:30000 remotepc


2) Use a python3 call without a CASA session:

Outside of CASA one can also create the http server in which to view a local weblog. From the command line simply type:

python3 -m http.server 8080 --bind 127.0.0.1    


The weblog can then be accessed in a web browser via the URL:

http://127.0.0.1:8080/"location_of_PL_weblog"/html/index.html


Note, this method requires python3, for which the version delivered with CASA can be used by setting it as an alias or by calling the full path. On MacOS this is found in "/Applications/CASA.app/Contents/MacOS/python3", or on Linux systems "'install_path'/casa-6.2.1-7-pipeline-2021.2.0.128/bin/python3"