Persistent Identifier Resolver

1. Description
2. Locations
- 2.1. Production
- 2.2. Test
3. Dependencies
4. Base URLs
5. Updating the resolver
- 5.1. Edit and Test
- 5.2. Productionize
6. Notes
7. Requirements

1 Description

See the 909 Registry for the function of the application.

2 Locations

2.1 Production

host: pi.lib.uchicago.edu
{source|executable}: /usr/local/www/pi/pi1001.{erl|beam}

2.2 Test

host: pi-test.lib.uchicago.edu
{source|executable}: /usr/local/www/pi-test/pi1001t.{erl|beam}

3 Dependencies

configuration file: /usr/local/etc/yaws/yaws.conf

yaws.conf contains the following sections relevant to this service.

For the production service:

ebin_dir = /usr/local/www/pi

<server pi.lib.uchicago.edu>
       port = 80
       listen = 0.0.0.0
       docroot = /usr/local/www/pi
       appmods = </1001, pi1001>
       dir_listings = false
</server>

For the test service:

ebin_dir = /usr/local/www/pi-test

<server pi-test.lib.uchicago.edu>
       port = 80
       listen = 0.0.0.0
       docroot = /usr/local/www/pi-test
       appmods = </1001, pi1001t>
       dir_listings = false
</server>

4 Base URLs

http://pi.lib.uchicago.edu/ http://pi-test.lib.uchicago.edu/

5 Updating the resolver

5.1 Edit and Test

ssh pi-test
cd /usr/local/www/pi-test
co -l pi1001t.erl
scp pi:/usr/local/www/pi/pi1001.erl . 
sed -e 's#%% http://pi.lib#%% http://pi-test.lib#g' -e 's:-module(pi1001):-module(pi1001t):g' pi1001.erl > pi1001t.erl
[edit pi1001t.erl]
erlc pi1001t.erl
(as the appropriate user, do the following)

Method 1 (on a FreeBSD system set up this way).

service yaws restart

Method 2 (on a system set up otherwise).

yaws --load pi1001t (See note below)

Test the new code using a few of the commented lines from /usr/local/www/pi-test/pi1001t.erl designed for the purpose, e.g., curl http://pi-test.lib.uchicago.edu/1001/test/test/test. These lines are to be found above each function clause.

Once you are satisfied with the changes:

ci -u pi1001t.erl

Load them into the production system, as follows.

5.2 Productionize

ssh pi
cd /usr/local/www/pi
cp pi1001.erl pi1001.erl_
scp pi-test:/usr/local/www/pi-test/pi1001t.erl .
sed -e s':pi1001t:pi1001:' -e s':pi-test:pi:'g pi1001t.erl > pi1001.erl
diff pi1001.erl pi1001.erl_
(note the differences; they should be as expected)
erlc pi1001.erl
(as the appropriate user, do the following)

Method 1 (on a FreeBSD system set up this way).

service yaws restart

Method 2 (on a system set up otherwise).

yaws --load pi1001 (See note below)

Test the new code using a few of the commented lines from /usr/local/www/pi/pi1001.erl designed for the purpose, e.g., curl http://pi.lib.uchicago.edu/1001/test/test/test. These lines are to be found above each function clause.

6 Notes

The master copy of the code is pi1001t.erl on pi-test.lib. This is the version that is kept under revision control. Changes are made to that copy first, then, once tested, they are moved into production as described above.

yaws –load [module] allows the reloading of a changed appmod into a running YAWS instance without stopping and starting YAWS. This assumes that yaws has already been started as follows:

yaws -D --heart

The resolver depends on http://marklogic.lib.uchicago.edu:8012/get-pi-pres.xqy. This means that any changes to, for example, the marklogic port number, need to be reflected in the corresponding erlang code. See the additional documentation for more information.

Note dependencies like these in the source code:

/usr/local/lib/erlang/lib/yaws-2.0.2/include/yaws_api.hrl
/usr/local/lib/erlang/lib/xmerl-1.38/include/xmerl.hrl

Paths will very likely change when software is upgraded. Make sure to update the source code accordingly.

7 Requirements

Erlang; YAWS. See http://yaws.hyber.org/appmods.yaws for appmods.