boutiques 0.5.11.post2

Import Your Tool

If you’re in the lucky set of people with a Boutiques descriptor from a previous schema iteration (such as 0.4), or you have a BIDS app, you can easily make yourself a descriptor from the command-line. For instance, let’s say you have a BIDS app at /awesome/app/, you would run:

$ bosh import bids descriptor.json /awesome/app/

Very exciting, you now have a Boutiques descriptor for your app! If you aren’t in one of those unique cases, unfortunately you’ll still need to generate your descriptor by hand according to the schema.

Create a New Descriptor

There are two additional ways to get you started with creating Boutiques descriptors, both wrapped up in the “create” module of Boutiques. First, if you just want an example descriptor that shows many of the properties you can later set in Boutiques, you should use the command line interface:

$ bosh create my-new-descriptor.json

However, if you want a bit more of a head start and your tool is built in Python using the argparse library, we can help more! In the Python script with your argparser defined, simply add the following lines to get yourself a minimal corresponding descriptor:

import boutiques.creator as bc
newDescriptor = bc.CreateDescriptor(myparser, execname="/command/to/run/exec")
newDescriptor.save("my-new-descriptor.json")

There are additional custom arguments which can be supplied to this script, such as tags for your tool. It is also worth noting that no interpretation of output files is attempted by this tool, so your descriptor could certainly be enhanced by addind these and other features available through Boutiques, such as tests, tags, error codes, groups, and container images.

Validation

You just created a Boutiques descriptor (compliant with the schema, of course) named descriptor.json - Congratulations! Now, you need to quickly validate it to make sure that you didn’t accidentally break any rules in this defintion (like requiring a “flag” input). You can validate your schema like this:

$ bosh validate descriptor.json

Depending on the status of your descriptor, bosh will either tell you it’s A-OK or tell you where the problems are and what you should fix. If you want to know more about some extra options packed into this validator, you can check them with bosh validate -h, as one may expect.

Simulate Execution

Now that you’ve got a valid descriptor, you need to make sure it is actually describing your tool and command-line. One of the easiest ways to do this is by simulating inputs for fake executions of your tool. You can do this using the exec function in bosh:

$ bosh exec simulate descriptor.json -r -n 5

You just simulated 5 sets of random inputs which were dumped to our terminal for you to validate. If anything seems fishy, you can update your descriptor and ensure you’re describing the command-line you want. If you had a particular set of inputs in mind, you could pass them in with the -i flag rather than using the -r and -n flags. Again, as I’m sure you’ve guessed, you can learn more here with bosh exec simulate -h.

Launch Your Tool

Your descriptor has now been vetted both by the validator and simulation to describe meaningful command-lines for your tool - now it’s time to put it to work! You can also use the exec function to launch an analysis, provided you’ve described your inputs in invocation.json with the matching key-value pairs as in your descriptor (this is called the invocationSchema, which you can also generate and learn about with bosh invocation). One catch: we assume you have Docker or Singularity installed. A fair assumption, nowadays? We hope so:

$ bosh exec launch descriptor.json invocation.json

You just launched your tool! You should be seeing outputs to your terminal, and by default your current working directory will be mounted to the container. You can mount more volumes with -v (consistent with Docker), and see what other options are available, such as switching users in the container, through the usual help menu, bosh exec launch -h.

Test Your Tool

You may now want to write a test for your descriptor, so that everyone using it could check that it produces correct results. This can be done by extending the tool descriptor with a tests property. For instance, the description below would test if the execution of the specified invocation returns with exit code 0 and produces a file in output logfile with the right MD5 hash.

"tests": [
        {
         "name": "test1",
         "invocation": {
                "config_num": 4,
                "enum_input": "val1",
                "file_input": "/tests/image.nii.gz",
                "list_int_input": [
                    1,
                    2,
                    3
                ],
                "str_input": [
                    "foo",
                    "bar"
                ]
            },
            "assertions": {
                "exit-code": 0,
                "output-files": [
                    {
                        "id": "logfile",
                        "md5-reference": "0868f0b9bf25d4e6a611be8f02a880b5"
                    }
                ]
            }
    }
]

You can then test your descriptor by simply typing:

$ bosh test descriptor.json

Evaluate Your Usage

If you’ve been using your tool and forget what exactly that output file will be named, or if it’s optional, but find re-reading the descriptor a bit cumbersome, you should just evaluate your invocation! If we wanted to check the location of our output corresponding to the id my_batmobile, or which of our inputs are numbers and optional, we could do the following two queries, respectively:

$ bosh evaluate descriptor.json invocation.json output-files/id=my_batmobile inputs/type=Number,optional=True
[{"my_batmobile": "/the/batcave/batmobile.car"}, {"bad_guys": "0", "times_saved_gotham": "5000"}]

Publish Your Tool

Congratulations on successfully running your analysis! So excited about your tool, you now want to share this descriptor with the world. This is the step which requires our GitHub libraries for Python which you got in the installation above - we’re going to make a fork of the NeuroLinks repository, add your tool, and get everying queued up for you to submit a Pull Request back with the brand new addition. There is a fair bit of metadata we’ll collect here, but the basics will be run with the following, assuming your descriptor lives in a Git-repo available at /utility/belt/, your name is Batman, and your tool lives at the url http://thebatcave.io (sorry to anyone who owns this url…):

$ bosh publish /utility/belt/ Batman http://thebatcave.io

Your tool is now being shared in a packaged and fully described fashion, making it easier than ever to reproduce and extend your work! As always, learn more about this feature with bosh publish -h.