127.0.0.1 at 23:16, 6 July 2007

2007-07-06T23:16:58Z

127.0.0.1 at 22:33, 6 July 2007

2007-07-06T22:33:55Z

127.0.0.1 at 22:21, 6 July 2007

2007-07-06T22:21:40Z

New page

= WERC datasite architecture =

WERC uses the Linux operating system for running downloads and
storing the data from the Campbell Scientific CR10 family of
dataloggers.

The following setup and conventions might be viewed as a type of
ad-hoc database, but the implementation is straightforward, using
ordinary directories and (''flat'') files.

==site root==

A '''site root''' directory is established on the data-gathering
host computer, e.g., /home/site/.

Individual sites could be found directly under this location, e.g.,
as:

/home/site/SITE1/
/home/site/SITE2/

but since we have so many different projects and locations, it makes sense to
provide subdirectories for those entities to help keep things organized,
and so the sites are usually defined under "area" directories:

/home/site/AREA1/SITE1/
/home/site/AREA1/SITE2/
/home/site/AREA2/SITE1/
/home/site/AREA2/SITE5/

Here we're showing two "areas" or "projects", but some of the sites contained
therein have the same names. In practice, it might be preferrable to keep the
site names unique, for example to allow utility programs to refer to the sites
without having to specify the area.

In any case, the "area" directories don't necessarily have any assumed
meaning or importance other than organization -- though they could do...

== site directory ==

A ''site'' -- here assumed to be a local or remote location with a data logger
and attached sensors -- is defined by a directory. What that directory contains
depends on how things are configured; a ''site'' could just have files in its
site directory, or it might include other subdirectories, e.g., var/, etc/, web/
tmp/, whatever makes sense for the intended use.

What '''really''' defines a ''site'' for the purposes here is the existence of
a '''site rc''' file.

== site rc file ==

In Unix-speak, ''rc'' files are plain text configuration files, very similar
to INI files found on (older? versions of) the Windows operating system. ('''rc''
itself might stand for "resource configuration", but other definitions can likewise
be found.)

For this WERC datasite system, we chose to use the filename '''siterc''' or it's
dotted (and so, "hidden") version, '''.siterc''', for storing configuration
settings.

Further, we defined a simple syntax for the site rc files:

section:
entry=value
...

where the rc file can contain any number of sections, and any number of
''entry=value'' entries under each section.

In practice, our convention has been to have an rc file section corresponding
to -- and sharing the name of -- the programs that are used to gather, process,
and move data on the site's behalf. Any program settings specific to the site
can then be viewed and configured directly in the rc file, e.g., using a text
editor -- subject to the normal user & group permissions inherent to the
Linux operating system.

@@ Line 76: / Line 76: @@
 Linux operating system.
-Here's an [[WERC-datasite-siterc-example|example]] '''siterc''' file from
+Here's an [[WERC-datasite-siterc-example|example '''siterc''' file]] from
 one of our active sites (with key settings changed).

← Older revision		Revision as of 22:33, 6 July 2007
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	editor -- subject to the normal user & group permissions inherent to the		editor -- subject to the normal user & group permissions inherent to the
	Linux operating system.		Linux operating system.
		+
		+	Here's an [[WERC-datasite-siterc-example\|example]] '''siterc''' file from
		+	one of our active sites (with key settings changed).

WERC datasite architecture - Revision history

127.0.0.1 at 23:16, 6 July 2007

127.0.0.1 at 22:33, 6 July 2007

127.0.0.1 at 22:21, 6 July 2007