About domino.yaml

domino.yaml is a file that defines Dataset configurations. It isn’t there by default, and should be created at the root of your project.

A Dataset configuration controls:

Existing Dataset Snapshots and how those Snapshots are mounted for input.
New directories that can become Snapshots and how those directories are mounted for output.

Schema

The domino.yaml file respects the following schema. Spaces matter.

datasetConfigurations: # contains array of configurations
 - name: string # identifier for this configuration
   inputs: # contains array of datasets to mount for input
     - path: string # path appended to /domino/datasets
       dataset: string # name of the dataset to mount as input
   outputs: # contains array of datasets to mount for input
     - path: string # path appended to /domino/datasets
       dataset: string # name of the dataset to mount for output

Valid fields in the YAML object are:

datasetConfigurations

This is a required field. It must be the first very first field on the first line. Only one of these fields can exist in the YAML file. This will contain an array of individual Dataset configurations.
name

Identifier for a specific configuration.
path

Desired mount path for Dataset Snapshot or new Snapshot directory.
dataset

Name of dataset. If configured as input, the latest Snapshot of the Dataset will be mounted by default. A different tagged Snapshot can be specified using a colon, like {dataset-name}:{tag}. For example: iris:test
inputs

Contains array of one or more [path, dataset] specifications to be mounted for input.
outputs

Contains array of one or more [path, dataset] specifications.

Error Handling

If you attempt to use an invalid domino.yaml, you may see one of these categories of error.

Invalid field that Domino does not recognize in a particular position

The error indicates the field found and shows valid field options for that position.

Example
```
Found invalid field in domino.yaml: “output”.
Valid field options: “inputs”, “outputs”, “name”
```
Valid field that Domino recognizes in a particular position, but there is an error.

An example of this is two outputs fields in one name block.

Example
```
There is an error in domino.yaml encountered while processing field “outputs”.
Please check all your “outputs” fields.
```

Valid field that Domino recognizes in an incorrect position.

An example of this is a valid field with the wrong indentation.

Example

There is a formatting error in domino.yaml encountered while processing field
“dataset”. Please check all your “dataset” fields.

Syntax error

An example of this is a missing quote. In some cases, we can identify the region the error occurs.

Example
```
There is a formatting error in domino.yaml in the block near 12.
```

Catch all

We are having trouble parsing domino.yaml.
Please see the support article linked above. If you still cannot identify
the problem, please email support@dominodatalab.com about your problem and include your domino.yaml.