Defining Images

# Defining Images Tom Gundersen Image Builder @ Red Hat slides: https://bit.ly/3yQAmpd --- ## Building Images --- ## osbuild - anyone can build images - we can build the same image twice  - comparable to an assembler - not a compiler - reproducible - low-level - pluggable - extensible - policy-less https://github.com/osbuild/osbuild ---- ### manifests - input to osbuild in JSON format - defines a set of filesystem trees  - e.g., one tree containing an image - same manifest produces the same* image - defined in terms of - a set of 'sources' and - a set of 'pipelines' ---- ### pipelines - defines a single filesystem tree - may consume other trees as input - defined as a sequence of 'stages' ---- ### stages - defines a modification to a filesystem tree - declarative - policy-less - reproducible - isolated from the host - scoped to one tool - sandboxes and unifies existing tools ---- ### example ```json { "version": "2", "pipelines": [ { "name": "os", "stages": [ { "type": "org.osbuild.rpm", ... }, ... ] }, ... ] } ``` --- ## Defining Images --- ## osbuild-composer - uniformly define all the images - one services to build everything for everyone everywhere - distros: - Fedora, CentOS Stream, RHEL - footprints: - Bare metal, Cloud, Virt, Edge - architectures: - x86_64, aarch64, ppc64le, s390x - available: on-prem, hosted, soon through koji https://github.com/osbuild/osbuild-composer ---- ### Public API - stable - very high-level - all artefacts end-to-end tested ---- ### Private API - unstable - not end-to-end tested - declarative - policy-rich - reproducible --- ## Image Kind ```go type ImageKind interface { InstantiateManifest(m *manifest.Manifest, ...) error ... } ``` ```go type OSTreeArchive struct { Platform platform.Platform OSCustomizations manifest.OSCustomizations Environment environment.Environment Workload workload.Workload OSTreeParent manifest.OSTree OSTreeRef string ... } ```  ---- ## Manifest ```go func (m Manifest) GetPackageSetChains() map[string][]rpmmd.PackageSet {...} func (m Manifest) Serialize( packageSets map[string][]rpmmd.PackageSpec) ([]byte], error) {...} ``` ---- ### Pipeline ```go type Pipeline interface { Name() string getBuildPackages() []string getPackageSetChain() []rpmmd.PackageSet serialize([]rpmmd.PackageSpec) osbuild2.Pipeline ... } ``` ---- ### Build Pipeline ```go func NewBuild(m *Manifest, runner runner.Runner, repos []rpmmd.RepoConfig) *Build {...} ``` ---- ### OS Pipeline ```go func NewOS(m *Manifest, buildPipeline *Build, platform platform.Platform, repos []rpmmd.RepoConfig) *OS {...} ``` ---- ### Hardware Platform ```go type Platform interface { GetArch() Arch GetBIOSPlatform() string GetUEFIVendor() string GetPackages() []string GetBuildPackages() []string ... } ``` ```go type X86 struct { BasePlatform BIOS bool UEFIVendor string } ```  ```go type Aarch64 struct { UEFIVendor string } ```  ---- ### RawImage Pipeline ```go func NewRawImage(m *Manifest, buildPipeline *Build, treePipeline *OS) *RawImage {...} ``` ---- ### Customizing Pipelines ```go type OS struct { PartitionTable *disk.PartitionTable Environment environment.Environment Workload workload.Workload ... } ``` ---- ### Environment ```go type Environment interface { GetPackages() []string GetServices() []string } ``` ```go type Azure struct {...} func (p *Azure) GetPackages() []string { return []string{"WALinuxAgent"} } func (p *Azure) GetServices() []string { return []string{"waagent"} } ```  ---- ### Workload ```go type Workload interface { GetPackages() []string GetServices() []string ... } ``` ```go type Custom struct { Packages []string Services []string ... } ```  ```go type MicroShift struct {} ```  ```go type Anaconda struct {} ```  --- ### Demo! :banana: ```sh go run ./cmd/osbuild-playground ``` <div style="text-align: right; color: grey; font-size: 0.5em"> using upstream VSCode devcontainer</div>