container-diff | container-diff : Diff your Docker containers | Continuous Deployment library

To use container-diff analyze to perform analysis on a single image, you need one Docker image (in the form of an ID, tarball, or URL from a repo). Once you have that image, you can run any of the following analyzers:. By default, with no --type flag specified, container-diff will run image size analysis.
In order to quickly make your own analyzer, follow these steps:. The image arguments passed to your analyzer contain the path to the unpacked tar representation of the image, as well as certain configuration information (e.g. environment variables upon image creation and image history). If using existing package tools, you should create the appropriate structs (e.g. SingleVersionPackageAnalyzeResult or SingleVersionPackageDiffResult) to analyze or diff. Otherwise, create your own structs which should yield information to fill an AnalyzeResult or DiffResult as the return type for Analyze() and Diff(), respectively, and should implement the Result interface, as in the next step. This is where you define how your analyzer should output for a human readable format (OutputText) and as a struct which can then be written to a .json file. See util/diff_output_utils.go and util/analyze_output_utils.go.
Determine if you can use existing analyzing or diffing tools. If you can make use of existing tools, you then need to construct the structs to feed into the tools by getting all of the packages for each image or the analogous quality to be analyzed. To determine if you can leverage existing tools, think through these questions:
Are you trying to analyze packages? Yes: Does the relevant package manager support different versions of the same package on one image? Yes: Implement getPackages to collect all versions of all packages within an image in a map[string]map[string]util.PackageInfo. Use GetMultiVersionMapDiff to diff map objects. See differs/node_diff.go or differs/pip_diff.go for examples. No: Implement getPackages to collect all versions of all packages within an image in a map[string]util.PackageInfo. Use GetMapDiff to diff map objects. See differs/apt_diff.go. No: Look to History and File System differs as models for diffing.
Write your analyzer driver in the differs directory, such that you have a struct for your analyzer type and two methods for that analyzer: Analyze for single image analysis and Diff for comparison between two images:
Create a struct following the Result interface by implementing the following two methods.
Add your analyzer to the Analyzers map in differs/differs.go with the corresponding Analyzer struct as the value.