Devfile Library

About

The Devfile Parser library is a Golang module that:

1. parses the devfile.yaml as specified by the api & schema.
2. writes to the devfile.yaml with the updated data.
3. generates Kubernetes objects for the various devfile resources.
4. defines util functions for the devfile.

Usage

The function documentation can be accessed via pkg.go.dev.

1. To parse a devfile, visit parse.go source file

   // ParserArgs is the struct to pass into parser functions which contains required info for parsing devfile.
   parserArgs := parser.ParserArgs{
    	Path:              path,
    	FlattenedDevfile:  &flattenedDevfile,
    	RegistryURLs:      registryURLs,
    	DefaultNamespace:  defaultNamespace,
    	Context:           context,
    	K8sClient:         client,
    }
   
   // Parses the devfile and validates the devfile data
   // if top-level variables are not substituted successfully, the warnings can be logged by parsing variableWarning
   devfile, variableWarning, err := devfilePkg.ParseDevfileAndValidate(parserArgs)

2. To get specific content from devfile

   // To get all the components from the devfile
   components, err := devfile.Data.GetComponents(DevfileOptions{})
   
   // To get all the components from the devfile with attributes tagged - tool: console-import
   // & import: {strategy: Dockerfile}
   components, err := devfile.Data.GetComponents(DevfileOptions{
      Filter: map[string]interface{}{
    		"tool": "console-import",
    		"import": map[string]interface{}{
    			"strategy": "Dockerfile",
    		},
    	},
   })
   
   // To get all the volume components
   components, err := devfile.Data.GetComponents(DevfileOptions{
    	ComponentOptions: ComponentOptions{
    		ComponentType: v1.VolumeComponentType,
    	},
   })
   
   // To get all the exec commands that belong to the build group
   commands, err := devfile.Data.GetCommands(DevfileOptions{
    	CommandOptions: CommandOptions{
    		CommandType: v1.ExecCommandType,
    		CommandGroupKind: v1.BuildCommandGroupKind,
    	},
   })

3. To get the Kubernetes objects from the devfile, visit generators.go source file

    // To get a slice of Kubernetes containers of type corev1.Container from the devfile component containers
    containers, err := generator.GetContainers(devfile)
   
    // To generate a Kubernetes deployment of type v1.Deployment
    deployParams := generator.DeploymentParams{
    	TypeMeta:          generator.GetTypeMeta(deploymentKind, deploymentAPIVersion),
    	ObjectMeta:        generator.GetObjectMeta(name, namespace, labels, annotations),
    	InitContainers:    initContainers,
    	Containers:        containers,
    	Volumes:           volumes,
    	PodSelectorLabels: labels,
    }
    deployment := generator.GetDeployment(deployParams)

4. To update devfile content

   // To update an existing component in devfile object
   err := devfile.Data.UpdateComponent(v1.Component{
   	    Name: "component1",
   	    ComponentUnion: v1.ComponentUnion{
   	    	Container: &v1.ContainerComponent{
   	    		Container: v1.Container{
   	    			Image: "image1",
                },
            },
        },
   })
   
   // To add a new component to devfile object
   err := devfile.Data.AddComponents([]v1.Component{
        {
           Name: "component2",
           ComponentUnion: v1.ComponentUnion{
               Container: &v1.ContainerComponent{
                   Container: v1.Container{
                       Image: "image2",
                   },
               },
           },
        },
   })
   
   // To delete a component from the devfile object
   err := devfile.Data.DeleteComponent(componentName)

5. To write to a devfile, visit writer.go source file

   // If the devfile object has been created with devfile path already set, can simply call WriteYamlDevfile to writes the devfile
   err := devfile.WriteYamlDevfile()
   
   
   // To write to a devfile from scratch
   // create a new DevfileData with a specific devfile version
   devfileData, err := data.NewDevfileData(devfileVersion)
   
   // set schema version
   devfileData.SetSchemaVersion(devfileVersion)
   
   // add devfile content use library APIs
   devfileData.AddComponents([]v1.Component{...})
   devfileData.AddCommands([]v1.Commands{...})
   ......
   
   // create a new DevfileCtx
   ctx := devfileCtx.NewDevfileCtx(devfilePath)
   err = ctx.SetAbsPath()
   
   // create devfile object with the new DevfileCtx and DevfileData
   devfile := parser.DevfileObj{
    	Ctx:  ctx,
    	Data: devfileData,
   }
    
   // write to the devfile on disk
   err = devfile.WriteYamlDevfile()

Projects using devfile/library

The following projects are consuming this library as a Golang dependency

• odo
• OpenShift Console

Tests

To run unit tests and api tests. Visit library tests to find out more information on tests

make test

Issues

Issues are tracked in the devfile/api repo with the label area/library

Releases

For devfile/library releases, please check the release page.