wordpress: pointing to #disqus_thread instead of #comments or #respond

So I upgraded to a simpler theme by Jared Erickson. It lets me focus more on the content on my journal and reduces the clutter and column width restriction because of a two column layout.

But this Less wordpress theme uses `comments_popup_link()` function which does not play well with my disqus comments widget.

A quick read on wordpress’ function reference shows me that there is no simple way to provide an option to ask the comments link to point to #disqus_thread (it shows #respond or #comments by default).

No problem, just a 5 minutes quick fix to implement

function disqus_count($disqus_shortname) {
    <code>echo</code> <code>'<a href="'</code><code>. get_permalink() .</code><code>'#disqus_thread"></a>'</code><code>;</code>

and to replace instances of

<?php comments_popup_link( __( 'Comment', 'less' ), __( '1 Comment', 'less' ), __( '% Comments', 'less' ) ); ?>;

with this

<?php disqus_count('calvinx'); ?>;

And we are good.

Installing pyscopg2 in virtualenv against postgresql92, instead of postgresql91

In my previous post, I explained how we can run postgresql92 and postgresql91 concurrently.  However, that post does not explain how we can ensure that the psycopg2 we install in our project’s python virtual environment will build against postgresql92 server.

When psycopg2 is installed (via `pip install psycopg2` for instance), psycopg2 depends on the presence of `pg_config` to locate the currently active postgresql version.

If we do `pg_config –sharedir`, we will see

calvin$ pg_config --sharedir

which tells us that if we run `pip install virtualenv`, we will essentially be building psycopg2 against postgresql91.

Fortunately for us, using macports, it’s trivial and completely painless to switch our postgresql server version.

calvin$ sudo port select --list postgresql
Available versions for postgresql:
 postgresql91 (active)

calvin$ sudo port select --set postgresql postgresql92
Selecting 'postgresql92' for 'postgresql' succeeded. 'postgresql92' is now active.

calvin$ sudo port select --list postgresql
Available versions for postgresql:
 postgresql92 (active)

Now, running `pip install psycopg2` in our python virtual environment will correctly build our psycopg2 against our postgresql 9.2 server.

calvin$ pip install psycopg2
Downloading/unpacking psycopg2
 Downloading psycopg2-2.4.5.tar.gz (719kB): 719kB downloaded
 Running setup.py egg_info for package psycopg2

 no previously-included directories found matching 'doc/src/_build'
Installing collected packages: psycopg2
 Running setup.py install for psycopg2
 building 'psycopg2._psycopg' extension
 /usr/bin/clang -fno-strict-aliasing -fno-common -dynamic -pipe -O2 -fwrapv -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -DPSYCOPG_DEFAULT_PYDATETIME=1 -DPSYCOPG_VERSION="2.4.5 (dt dec pq3 ext)" -DPG_VERSION_HEX=0x090202 -DPSYCOPG_EXTENSIONS=1 -DPSYCOPG_NEW_BOOLEAN=1 -DHAVE_PQFREEMEM=1 -I/opt/local/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -I. -I/opt/local/include/postgresql92 -I/opt/local/include/postgresql92/server -c psycopg/psycopgmodule.c -o build/temp.macosx-10.7-x86_64-2.7/psycopg/psycopgmodule.o
 /usr/bin/clang -fno-strict-aliasing -fno-common -dynamic -pipe -O2 -fwrapv -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -DPSYCOPG_DEFAULT_PYDATETIME=1 -DPSYCOPG_VERSION="2.4.5 (dt dec pq3 ext)" -DPG_VERSION_HEX=0x090202 -DPSYCOPG_EXTENSIONS=1 -DPSYCOPG_NEW_BOOLEAN=1 -DHAVE_PQFREEMEM=1 -I/opt/local/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -I. -I/opt/local/include/postgresql92 -I/opt/local/include/postgresql92/server -c psycopg/green.c -o build/temp.macosx-10.7-x86_64-2.7/psycopg/green.o
 /usr/bin/clang -fno-strict-aliasing -fno-common -dynamic -pipe -O2 -fwrapv -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -DPSYCOPG_DEFAULT_PYDATETIME=1 -DPSYCOPG_VERSION="2.4.5 (dt dec pq3 ext)" -DPG_VERSION_HEX=0x090202 -DPSYCOPG_EXTENSIONS=1 -DPSYCOPG_NEW_BOOLEAN=1 -DHAVE_PQFREEMEM=1 -I/opt/local/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -I. -I/opt/local/include/postgresql92 -I/opt/local/include/postgresql92/server -c psycopg/pqpath.c -o build/temp.macosx-10.7-x86_64-2.7/psycopg/pqpath.o
 /usr/bin/clang -fno-strict-aliasing -fno-common -dynamic -pipe -O2 -fwrapv -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -DPSYCOPG_DEFAULT_PYDATETIME=1 -DPSYCOPG_VERSION="2.4.5 (dt dec pq3 ext)" -DPG_VERSION_HEX=0x090202 -DPSYCOPG_EXTENSIONS=1 -DPSYCOPG_NEW_BOOLEAN=1 -DHAVE_PQFREEMEM=1 -I/opt/local/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -I. -I/opt/local/include/postgresql92 -I/opt/local/include/postgresql92/server -c psycopg/utils.c -o build/temp.macosx-10.7-x86_64-2.7/psycopg/utils.o
 /usr/bin/clang -fno-strict-aliasing -fno-common -dynamic -pipe -O2 -fwrapv -DNDEBUG -g -fwrapv -O3 -Wall -Wstrict-prototypes -DPSYCOPG_DEFAULT_PYDATETIME=1 -DPSYCOPG_VERSION="2.4.5 (dt dec pq3 ext)" -DPG_VERSION_HEX=0x090202 -DPSYCOPG_EXTENSIONS=1 -DPSYCOPG_NEW_BOOLEAN=1 -DHAVE_PQFREEMEM=1 -I/opt/local/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7 -I. -I/opt/local/include/postgresql92 -I/opt/local/include/postgresql92/server -c psycopg/bytes_format.c -o build/temp.macosx-10.7-x86_64-2.7/psycopg/bytes_format.o


Next! :-)

geodjango: django tests break when creating new postgis test databases

The new postgis 2.0 library (easily installed via `sudo port install postgis2 +postgresql92` if you are using macports as mentioned in my previous post) helps us convert a standard postgresql database into a spatially-aware database via the simple `CREATE EXTENSION postgis;` command:

$  psql92 -p 5433 -U postgres -d your_db

psql92 (9.2.1)
Type "help" for help.
your_db=#  CREATE EXTENSION postgis;

Unfortunately, when we run our django tests, `test_your_db`, which is newly created by django’s test runner whenever the test begins, will not be postgis-enabled. This leads immediately to test failure when our code fails to recognize the Geometry fields in our project’s GeoDjango models.

To get around this problem, we will need to specifically set up a `template_postgis` template database, much like what we did before postgis 2.0 (reference django docs https://docs.djangoproject.com/en/dev/ref/contrib/gis/install/postgis/#creating-a-spatial-database-template-for-earlier-versions).  But because I am running an instance of postgresql 9.1 server and an instance of 9.2 server concurrently, I will need to modify my commands a little.

Like this:-

calvin$ psql92 -p 5433 -U postgres
psql92 (9.2.1)
Type "help" for help.

postgres=# CREATE DATABASE template_postgis ENCODING='utf-8';
postgres=# UPDATE pg_database SET datistemplate='true' WHERE datname='template_postgis';
postgres=# \q

calvin$ POSTGIS_SQL_PATH=/opt/local/share/postgresql92/contrib/postgis-2.0

calvin$ psql92 -p 5433 -U postgres -d template_postgis -f $POSTGIS_SQL_PATH/postgis.sql

calvin$ psql92 -p 5433 -U postgres -d template_postgis -f $POSTGIS_SQL_PATH/spatial_ref_sys.sql

calvin$ psql92 -p 5433 -U postgres -d template_postgis -c "GRANT ALL ON geometry_columns TO PUBLIC;"

calvin$ psql92 -p 5433 -U postgres -d template_postgis -c "GRANT ALL ON geography_columns TO PUBLIC;"

calvin$ psql92 -p 5433 -U postgres -d template_postgis -c "GRANT ALL ON spatial_ref_sys TO PUBLIC;"

With this, running `./manage.py test` with your geodjango-based application will work perfectly fine because django’s default test runner will look for the template_postgis template database to instantiate our now spatially-aware test database.