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.
5. downloads resources from a parent devfile if specified in the devfile.yaml

Private repository support

Tokens are required to be set in the following cases:

1. parsing a devfile from a private repository
2. parsing a devfile containing a parent devfile from a private repository [1]
3. parsing a devfile from a private repository containing a parent devfile from a public repository [2]

Set the token for the repository:

parser.ParserArgs{
	...
	// URL must point to a devfile.yaml
	URL: <url-to-devfile-on-supported-git-provider-repo>/devfile.yaml
	Token: <repo-personal-access-token>
	...
}

Note: The url must also be set with a supported git provider repo url.

Minimum token scope required:

1. GitHub: Read access to code
2. GitLab: Read repository
3. Bitbucket: Read repository

Note: To select token scopes for GitHub, a fine-grained token is required.

For more information about personal access tokens:

1. GitHub docs
2. GitLab docs
3. Bitbucket docs

[1] Currently, this works under the assumption that the token can authenticate the devfile and the parent devfile; both devfiles are in the same repository.

[2] In this scenario, the token will be used to authenticate the main 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,
    	ConvertKubernetesContentInUri:  &convertKubernetesContentInUri
    	RegistryURLs:                   registryURLs,
    	DefaultNamespace:               defaultNamespace,
    	Context:                        context,
    	K8sClient:                      client,
   		ExternalVariables:              externalVariables,
    }
   
   // 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 override the HTTP request and response timeouts for a devfile with a parent reference from a registry URL, specify the HTTPTimeout value in the parser arguments

      // specify the timeout in seconds  
      httpTimeout := 20 
      parserArgs := parser.ParserArgs{
         HTTPTimeout: &httpTimeout
      }

3. 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,
    	},
   })

4. 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)

5. 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)

6. 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()

7. To parse the outerloop Kubernetes/OpenShift component's uri or inline content, call the read and parse functions

   // Read the YAML content
   values, err := ReadKubernetesYaml(src, fs)
   
   // Get the Kubernetes resources
   resources, err := ParseKubernetesYaml(values)

8. By default, the parser will set all unset boolean properties to their spec defined default values. Clients can override this behaviour by specifiying the parser argument SetBooleanDefaults to false

   setDefaults := false
   parserArgs := parser.ParserArgs{
    	SetBooleanDefaults:               &setDefaults,
   }

9. When parsing a devfile that contains a parent reference, if the parent uri is a supported git provider repo url with the correct personal access token, all resources from the parent git repo excluding the parent devfile.yaml will be downloaded to the location of the devfile being parsed. Note: The URL must point to a devfile.yaml

   schemaVersion: 2.2.0
   ...
   parent:
      uri: <uri-to-parent-devfile>/devfile.yaml
   ...

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.

Contributing

Please see our contributing.md.