The module commands can now produce JSON formatted output which is passed
to the caller. The output should conform to the JSON API as closely as
possible.
Currently, the REST API wraps all JSON produced by module commands inside
a meta-object of the following type:
{
"meta": <output of module command>
}
This allows the output to be JSON API conformant without modifying the
modules and allows incremental updates to code.
The PATCH method should now be used instead the PUT method to update
resources. As PUT request bodies should represent complete resources, the
use of PUT to update resources is no longer supported.
Altered tests to use PATCH instead of PUT for updating resources.
The module command self links now point to an endpoint that executes the
module command. Depending on the type of the module command, either a GET
or a POST request must be made.
The /maxscale/ resource now supports PUT requests which modify core
parameters. As not all parameters can be changed at runtime, only
modifications to parameters that support runtime configuration are
allowed.
The /users/ resource shows all user accounts that can be used with
MaxScale. This resource is further split into two resource collections,
/users/inet and /users/unix, which contain the network users and Linux
accounts respectively.
The /maxscale/ resource now has values for most of the configuration
parameters in the [maxscale] section as well as the version, commit and
uptime information.
The REST API now supports the If-Modified-Since, If-Unmodified-Since,
If-Match and If-None-Match headers and returns the correct response if the
conditional fails.
Added tests for the date parsing and expanded the HTTP header tests in the
REST API test suite.
The resource system now tracks both the time when a resource was last
modified and the revision number of the resource. This allows working
Last-Modified and ETag headers to be generated by the REST API.
The If-Modified-Since and If-None-Match request headers are not yet
processed and using them will always return the resource instead of a 304
Not Modified response.
Returning 204 No Content removes the cost of always sending back the
modified resource. If the modified resource is required, a GET request
should be made to retrieve it.
Updated tests to account for this change.
The listeners under the /services/:service/listeners collection are now
fully JSON API compliant resources.
The listeners could also be exposed as a /listeners collection to easily
group all listener type resources in one place. This approach does has
some semantical and practical problems, namely the fact that each listener
has a many-to-one relationship with its service and listeners by
themselves can't exist alone.
The JSON API specification suggests that the API returns the 403 Forbidden
error when the user does an invalid request. The 400 Bad Request isn't the
ideal error for cases where the syntax is correct but the action being
performed is wrong.
The modules, their types and default values are exposed via the
/maxscale/modules resource. Currently, only a list of resources can be
exposed as the externally exposed module object (MXS_MODULE) does not have
the name and type information in it.
Destroyed servers were still shown as a part of the servers resource
collection.
If a parameter defined in persisted configurations was replaced, the value
would be appended to itself after it was replaced.
Return correct error codes for internal errors.
The server check was checking for old parameter locations.
Service parameters can now be altered with a PUT request to the REST
API. This allows general level parameters to be altered.
Module specific parameters need to be altered with a different mechanism,
namely the module command system. This requires that a generic way to call
a function needs to be devised.
The PATCH method isn't supported in older versions of microhttpd. As this
functionality wasn't used, it can be removed until it is needed. The PUT
method already allows updates by defining complete resources so PATCH is
only an improvement, not a requirement.
Monitor resources can now be altered with a PUT request. The method allows
alterations on all parameters that the maxadmin `alter monitor` command
allows.
The /sessions/ resource was not implemented due to changes in the core
polling mechanics. With the new worker thread messaging system, sessions
can be listed in a safe manner.
All resources now support HEAD and OPTIONS methods.
The HEAD response is generated by truncating a GET request on the same
resource. This does not work with other methods as they could require a
message body.
The server can now be modified with a PUT request of a modified server
resource. The server resource was reorganized to have the parameters as a
separate entity from the other more general entities of the resource.
The PUT/POST functions return a more appropriate error message when no
request body is provided.
Moved some of the constant names used in server.cc into the config.h
header.
Cleaned up various parts of the resource, request and response class
headers.
Moved `using` declarations into .cc files.
Made the Resource class non-copyable as it isn't really meant to be
copied.
The resources are now declared by simply typing the path that they match
and providing a callback for that path. This makes it easier to add new
resources without having to create a new class for each added resource
endpoint. It also removes some of the pathname processing that was done
inside the child class handler functions.
The HTTP side of the REST API is better handled with an actual
library. The libmicrohttpd library provides a convenient way of handling
the HTTP traffic between the clients and MaxScale.
Monitors can now be printed in JSON format. The REST API resource
`/monitors` accepts GET requests and returns a JSON representation of the
monitors as a response.
Both the filters and services can be queried via the REST API now that
these resources can be expressed in JSON format.
As with the other resources, these directly call the functions that
generate the data. This will be done via the inter-thread messaging system
once it's in place.
The REST API now prints individual sessions and servers. It also lists all
servers if no specific server is given.
The functions directly call the printing functions when they should be
using the inter-thread messaging system. When the messaging system is
ready, these functions should be updated.
The resources now properly process parts of the uri. This allows, for
example, certain sessions to be inspected. The current functionality is
only intended for testing and provides no useful functionality.
The actions taken by the resource manager are not done via the
inter-thread messaging system. When the implementation of the messages and
the JSON representation of the resources is done, the REST API resource
can actually be used.
The Resource class is intended to be an abstraction of a resource
tree. Each node in the tree can perform actions. The tree is traversed
depth first so that deeper command paths resolve to the correct nodes.
Currently all the base resources defined in the REST API documents are
implemented in a way that they return a 200 OK response to all
requests. When the internal data can be represented as JSON, the resources
can be hooked up to functions that generate JSON.
