Java's ScriptEnging is used to transform design doc JS objects into
valid JSON. A custom CouchDbConnector has been implemented to handle
this transformation and create the design docs in the database at
startup.

Priortizing v3 caused problems for v2 clients on POST requests.

This decouples type identifiers used in CouchDB from Java type names.

The creation of new documents is blocked if an empty _rev is set.

Ektorp is introduced as a replacement for CouchDB4J.

Functions need to be stringified to create valid JSON which is accepted
by CouchDB.

Additionally, removed obsolete TODO comment.

The use of a proxy is no longer necessary with AspectJ.

Daniel Gerhardt authored 7 years ago and Daniel Gerhardt committed 7 years ago

This eliminates issues in edge cases like calling annotated methods from
inside the same class. The use of `AopContext.currentProxy()` and the
`exposeProxy` setting are no longer necessary for these cases.

Scheduling was disabled unintentionally with the config migration in
commit 2ecbfec8.

Annotations are added as a replacement for <task:annotation-driven />.

Since we do not use a SecurityFilter, the previously visited page is not
saved in the session.

This improves/fixes compatibility with third-party OAuth APIs.

Consistently prioritize the `api.path` setting before falling back to
`servletContext.getContextPath()`.

Daniel Gerhardt authored 7 years ago and Daniel Gerhardt committed 7 years ago

This should massively reduce the time needed for session creation.
Additionally, the `Transactional` annotation has been removed because
it did not have any effect in this case.

Log level for DB logging was overriden by the fallbacki value in some
cases.

There should not be any Servlet container around which does not support
JSON by default. The backend does not have an AppCache manifest so a
mapping is not needed here either.

Since error handlers use JSON for responses there is no need for HTML
error pages anymore.

API v3:
* Media type: application/vnd.de.thm.arsnova.v3+json
* Serializes date as strings conforming to ISO 8601.

API v2:
* Media type: application/vnd.de.thm.arsnova.v2+json
* Serializes dates as timestamps including nanoseconds.

An indentation setting has been added: `api.indent-response-body:false`.

Add messages to exceptions and slightly refactor exception handling.

Exceptions are now always passed to the logger. The logger decides based
on configuration whether and how they are logged. Logging messages were
adjusted for consistency.

Execption messages in API responses is disabled by default because they
can contain sensitive data. The config property
`api.expose-exception-messages` has been added and is described in the
developer documentation.