It used to be that you would give the target table name as an option to the
PostgreSQL connection string, which is untasteful:
load ... into pgsql://user@host/dbname?tablename=foo.bar ...
Or even, for backwards compatibility:
load ... into pgsql://user@host/dbname?foo.bar ...
The new syntax makes provision for a separate clause for the target table
name, possibly schema-qualified:
load ... into pgsql://user@host/dbname target table foo.bar ...
Which is much better, in particular when used together with the target
columns clause.
Implementing this seemingly quite small feature had impact on many parsing
related features of pgloader, such as the regression testing facility. So
much so that some extra refactoring got into its way here, around the
lisp-code-for-loading-from-<source> functions and their usage in
`load-data'.
While at it, this patch simplifies a lot the `load-data' function by making
a good use of &allow-other-keys and :allow-other-keys t.
Finally, this patch splits main.lisp into main.lisp and api.lisp, with the
latter intended to contain functions for Common Lisp programs wanting to use
pgloader as a library. The API itself is still the same as before this
patch, tho. Just in another file for clarity.
The PostgreSQL COPY protocol requires an explicit initialization phase
that may fail, and in this case the Postmodern driver transaction is
already dead, so there's no way we can even send ABORT to it.
Review the error handling of our copy-batch function to cope with that
fact, and add some logging of non-retryable errors we may have.
Also improve the thread error reporting when using a binary image from
where it might be difficult to open an interactive debugger, while still
having the full blown Common Lisp debugging experience for the project
developers.
Add a test case for a missing column as in issue #339.
Fix#339, see #337.
