Snappy

Grab attestable snapshots of API responses

Snappy is a simple tool that grabs snapshots of API response data to be able to fix it in a signed attestation.

The API call is contructed according to a spec file, to generate a snapshot you simply call snappy and pass it a spec:

snappy snap spec.yaml

Snapshot Spec

The API snapshots are controlled through a spec file written in yaml. The spec describes some basic metadata about the object being queried, and the API endpoint to hit.

In order to avoid leaking snesitive data, only data specifically configured in the spec will be written in the resulting snapshot.

An example spec YAML file looks like this:

---
id: https://github.com/{$ORG}/{$REPO}
type: http://github.com/carabiner-dev/snapi/specs/repo.yaml
endpoint: repos/{$ORG}/{$REPO}
method:  GET
mask:
  - id
  - node_id
  - name
  - full_name
  - html_url
  - git_url
  - license
  - has_discussions
  - has_issues
  - homepage
  - fork
  - visibility
  - security_and_analysis
  - web_commit_signoff_required

From the resulting data structure, only those fields named in the field mask will be transferred to the resulting snapshot.

Variable Support

As seen in the example above, the snapshot spec can have variables that can be substituted when invoking snappy:

id: https://github.com/{$ORG}/{$REPO}
type: http://github.com/carabiner-dev/snapi/specs/repo.yaml
endpoint: repos/{$ORG}/{$REPO}

To define a value for the $ORG and $REPO variables, simply pass them in the command line invocation:

snappy snap --var ORG=myorg --var REPO=myrepo spec.yaml

Install

TBD