Module: index

The Nx Devkit is the underlying technology used to customize Nx to support different technologies and custom use-cases. It contains many utility functions for reading and writing files, updating configuration, working with Abstract Syntax Trees(ASTs), and more.

As with most things in Nx, the core of Nx Devkit is very simple. It only uses language primitives and immutable objects (the tree being the only exception).

Table of contents

Project Graph Enumerations

• DependencyType

Utils Enumerations

• ChangeType

Project Graph Classes

• ProjectGraphBuilder

Utils Classes

• Hasher

Workspace Classes

• Workspaces

Commands Interfaces

• Target

Other Interfaces

• NxPlugin

Project Graph Interfaces

• FileData
• ProjectFileMap
• ProjectGraph
• ProjectGraphDependency
• ProjectGraphExternalNode
• ProjectGraphProcessorContext
• ProjectGraphProjectNode
• ProjectGraphV4

Tree Interfaces

• FileChange
• Tree

Utils Interfaces

• DefaultTasksRunnerOptions
• Hash
• JsonParseOptions
• JsonSerializeOptions
• RemoteCache
• StringDeletion
• StringInsertion

Workspace Interfaces

• ExecutorContext
• ExecutorsJson
• GeneratorsJson
• HasherContext
• ImplicitJsonSubsetDependency
• MigrationsJson
• NxAffectedConfig
• NxJsonConfiguration
• ProjectConfiguration
• TargetConfiguration
• TargetDependencyConfig
• Task
• TaskGraph
• Workspace
• WorkspaceJsonConfiguration

Generators Type aliases

• WorkspaceConfiguration

Other Type aliases

• ProjectTargetConfigurator

Package Manager Type aliases

• PackageManager

Project Graph Type aliases

• ProjectGraphNode

Utils Type aliases

• StringChange

Workspace Type aliases

• CustomHasher
• Executor
• Generator
• GeneratorCallback
• ImplicitDependencyEntry
• ProjectType
• TaskGraphExecutor

Logger Variables

• logger

Utils Variables

• appRootPath
• cacheDir
• output
• workspaceRoot

Functions

• addDependenciesToPackageJson
• addProjectConfiguration
• applyChangesToString
• convertNxExecutor
• convertNxGenerator
• createProjectGraphAsync
• defaultTasksRunner
• detectPackageManager
• formatFiles
• generateFiles
• getOutputsForTargetAndConfiguration
• getPackageManagerCommand
• getPackageManagerVersion
• getProjects
• getWorkspaceLayout
• getWorkspacePath
• installPackagesTask
• isStandaloneProject
• joinPathFragments
• moveFilesToNewDirectory
• names
• normalizePath
• offsetFromRoot
• parseJson
• parseTargetString
• readCachedProjectGraph
• readJson
• readJsonFile
• readNxJson
• readProjectConfiguration
• readTargetOptions
• readWorkspaceConfiguration
• removeDependenciesFromPackageJson
• removeProjectConfiguration
• reverse
• runExecutor
• serializeJson
• stripIndents
• stripJsonComments
• targetToTargetString
• toJS
• updateJson
• updateProjectConfiguration
• updateTsConfigsToJs
• updateWorkspaceConfiguration
• visitNotIgnoredFiles
• workspaceLayout
• writeJson
• writeJsonFile

Project Graph Enumerations

DependencyType

• DependencyType: Object

Utils Enumerations

ChangeType

• ChangeType: Object

Project Graph Classes

ProjectGraphBuilder

• ProjectGraphBuilder: Object

Utils Classes

Hasher

• Hasher: Object

Workspace Classes

Workspaces

• Workspaces: Object

Commands Interfaces

Target

• Target: Object

Other Interfaces

NxPlugin

• NxPlugin: Object

A plugin for Nx

Project Graph Interfaces

FileData

• FileData: Object

ProjectFileMap

• ProjectFileMap: Object

ProjectGraph

• ProjectGraph<T>: Object

Type parameters

ProjectGraphDependency

• ProjectGraphDependency: Object

ProjectGraphExternalNode

• ProjectGraphExternalNode: Object

ProjectGraphProcessorContext

• ProjectGraphProcessorContext: Object

ProjectGraphProjectNode

• ProjectGraphProjectNode<T>: Object

Type parameters

ProjectGraphV4

• ProjectGraphV4<T>: Object

Type parameters

Tree Interfaces

FileChange

• FileChange: Object

Tree

• Tree: Object

Utils Interfaces

DefaultTasksRunnerOptions

• DefaultTasksRunnerOptions: Object

Hash

• Hash: Object

JsonParseOptions

• JsonParseOptions: Object

JsonSerializeOptions

• JsonSerializeOptions: Object

RemoteCache

• RemoteCache: Object

StringDeletion

• StringDeletion: Object

StringInsertion

• StringInsertion: Object

Workspace Interfaces

ExecutorContext

• ExecutorContext: Object

ExecutorsJson

• ExecutorsJson: Object

GeneratorsJson

• GeneratorsJson: Object

HasherContext

• HasherContext: Object

ImplicitJsonSubsetDependency

• ImplicitJsonSubsetDependency<T>: Object

Type parameters

MigrationsJson

• MigrationsJson: Object

NxAffectedConfig

• NxAffectedConfig: Object

NxJsonConfiguration

• NxJsonConfiguration<T>: Object

Type parameters

ProjectConfiguration

• ProjectConfiguration: Object

TargetConfiguration

• TargetConfiguration: Object

TargetDependencyConfig

• TargetDependencyConfig: Object

Task

• Task: Object

TaskGraph

• TaskGraph: Object

Workspace

• Workspace: Object

WorkspaceJsonConfiguration

• WorkspaceJsonConfiguration: Object

Generators Type aliases

WorkspaceConfiguration

Ƭ WorkspaceConfiguration: Omit<WorkspaceJsonConfiguration, "projects"> & Partial<NxJsonConfiguration>

Other Type aliases

ProjectTargetConfigurator

Ƭ ProjectTargetConfigurator: (file: string) => Record<string, TargetConfiguration>

Type declaration

▸ (file): Record<string, TargetConfiguration>

Parameters

Returns

Record<string, TargetConfiguration>

Package Manager Type aliases

PackageManager

Ƭ PackageManager: "yarn" | "pnpm" | "npm"

Project Graph Type aliases

ProjectGraphNode

Ƭ ProjectGraphNode<T>: ProjectGraphProjectNode<T> | ProjectGraphExternalNode

Type parameters

Utils Type aliases

StringChange

Ƭ StringChange: StringInsertion | StringDeletion

Workspace Type aliases

CustomHasher

Ƭ CustomHasher: (task: Task, context: HasherContext) => Promise<Hash>

Type declaration

▸ (task, context): Promise<Hash>

Parameters

Returns

Promise<Hash>

Executor

Ƭ Executor<T>: (options: T, context: ExecutorContext) => Promise<Object> | AsyncIterableIterator<Object>

Type parameters

Type declaration

▸ (options, context): Promise<Object> | AsyncIterableIterator<Object>

Implementation of a target of a project

Parameters

Returns

Promise<Object> | AsyncIterableIterator<Object>

Generator

Ƭ Generator<T>: (tree: any, schema: T) => void | GeneratorCallback | Promise<void | GeneratorCallback>

Type parameters

Type declaration

▸ (tree, schema): void | GeneratorCallback | Promise<void | GeneratorCallback>

A function that schedules updates to the filesystem to be done atomically

Parameters

Returns

void | GeneratorCallback | Promise<void | GeneratorCallback>

GeneratorCallback

Ƭ GeneratorCallback: () => void | Promise<void>

Type declaration

▸ (): void | Promise<void>

A callback function that is executed after changes are made to the file system

Returns

void | Promise<void>

ImplicitDependencyEntry

Ƭ ImplicitDependencyEntry<T>: Object

Type parameters

Index signature

▪ [key: string]: T | ImplicitJsonSubsetDependency<T>

ProjectType

Ƭ ProjectType: "library" | "application"

TaskGraphExecutor

Ƭ TaskGraphExecutor<T>: (taskGraph: TaskGraph, options: Record<string, T>, overrides: T, context: ExecutorContext) => Promise<Record<string, Object>>

Type parameters

Type declaration

▸ (taskGraph, options, overrides, context): Promise<Record<string, Object>>

Implementation of a target of a project that handles multiple projects to be batched

Parameters

Returns

Promise<Record<string, Object>>

Logger Variables

logger

• logger: Object

Type declaration

Utils Variables

appRootPath

• appRootPath: string

cacheDir

• cacheDir: string

output

• output: CLIOutput

workspaceRoot

• workspaceRoot: string = appRootPath

Functions

addDependenciesToPackageJson

▸ addDependenciesToPackageJson(tree, dependencies, devDependencies, packageJsonPath?): GeneratorCallback

Add Dependencies and Dev Dependencies to package.json

For example:

1addDependenciesToPackageJson(tree, { react: 'latest' }, { jest: 'latest' });

This will add react and jest to the dependencies and devDependencies sections of package.json respectively.

Parameters

Returns

GeneratorCallback

Callback to install dependencies only if necessary. undefined is returned if changes are not necessary.

addProjectConfiguration

▸ addProjectConfiguration(tree, projectName, projectConfiguration, standalone?): void

Adds project configuration to the Nx workspace.

The project configuration is stored in workspace.json or the associated project.json file. The utility will update either files.

Parameters

Returns

void

applyChangesToString

▸ applyChangesToString(text, changes): string

Applies a list of changes to a string's original value.

This is useful when working with ASTs.

For Example, to rename a property in a method's options:

1const code = `bootstrap({
2  target: document.querySelector('#app')
3})`;
4
5const indexOfPropertyName = 13; // Usually determined by analyzing an AST.
6const updatedCode = applyChangesToString(code, [
7  {
8    type: ChangeType.Insert,
9    index: indexOfPropertyName,
10    text: 'element',
11  },
12  {
13    type: ChangeType.Delete,
14    start: indexOfPropertyName,
15    length: 6,
16  },
17]);
18
19bootstrap({
20  element: document.querySelector('#app'),
21});

Parameters

Returns

string

convertNxExecutor

▸ convertNxExecutor(executor): any

Convert an Nx Executor into an Angular Devkit Builder

Use this to expose a compatible Angular Builder

Parameters

Returns

any

convertNxGenerator

▸ convertNxGenerator<T>(generator, skipWritingConfigInOldFormat?): (generatorOptions: T) => (tree: any, context: any) => Promise<any>

Convert an Nx Generator into an Angular Devkit Schematic.

Type parameters

Parameters

Returns

fn

▸ (generatorOptions): (tree: any, context: any) => Promise<any>

Parameters

Returns

fn

▸ (tree, context): Promise<any>

Parameters

Returns

Promise<any>

createProjectGraphAsync

▸ createProjectGraphAsync(): Promise<ProjectGraph>

Computes and returns a ProjectGraph.

Nx will compute the graph either in a daemon process or in the current process.

Nx will compute it in the current process if:

• The process is running in CI (CI env variable is to true or other common variables used by CI providers are set).
• It is running in the docker container.
• The daemon process is disabled because of the previous error when starting the daemon.
• NX_DAEMON is set to false.
• useDaemon is set to false in nx.json

NX_DAEMON env variable takes precedence:

• If it is set to true, the daemon will always be used.
• If it is set to false, the graph will always be computed in the current process.

Tip: If you want to debug project graph creation, run your command with NX_DAEMON=false.

Nx uses two layers of caching: the information about explicit dependencies stored on the disk and the information stored in the daemon process. To reset both run: nx reset.

Returns

Promise<ProjectGraph>

defaultTasksRunner

▸ Const defaultTasksRunner(tasks, options, context?): any

Parameters

Returns

any

detectPackageManager

▸ detectPackageManager(dir?): PackageManager

Detects which package manager is used in the workspace based on the lock file.

Parameters

Returns

PackageManager

formatFiles

▸ formatFiles(tree): Promise<void>

Formats all the created or updated files using Prettier

Parameters

Returns

Promise<void>

generateFiles

▸ generateFiles(tree, srcFolder, target, substitutions): void

Generates a folder of files based on provided templates.

While doing so it performs two substitutions:

• Substitutes segments of file names surrounded by __
• Uses ejs to substitute values in templates

Examples:

1generateFiles(tree, path.join(__dirname, 'files'), './tools/scripts', {
2  tmpl: '',
3  name: 'myscript',
4});

This command will take all the files from the files directory next to the place where the command is invoked from. It will replace all __tmpl__ with '' and all __name__ with 'myscript' in the file names, and will replace all <%= name %> with myscript in the files themselves. tmpl: '' is a common pattern. With it you can name files like this: index.ts__tmpl__, so your editor doesn't get confused about incorrect TypeScript files.

Parameters

Returns

void

getOutputsForTargetAndConfiguration

▸ getOutputsForTargetAndConfiguration(task, node): any

Returns the list of outputs that will be cached.

Parameters

Returns

any

getPackageManagerCommand

▸ getPackageManagerCommand(packageManager?): PackageManagerCommands

Returns commands for the package manager used in the workspace. By default, the package manager is derived based on the lock file, but it can also be passed in explicitly.

Example:

1execSync(`${getPackageManagerCommand().addDev} my-dev-package`);

Parameters

Returns

PackageManagerCommands

getPackageManagerVersion

▸ getPackageManagerVersion(packageManager?): string

Returns the version of the package manager used in the workspace. By default, the package manager is derived based on the lock file, but it can also be passed in explicitly.

Parameters

Returns

string

getProjects

▸ getProjects(tree): Map<string, ProjectConfiguration>

Get a map of all projects in a workspace.

Use readProjectConfiguration if only one project is needed.

Parameters

Returns

Map<string, ProjectConfiguration>

getWorkspaceLayout

▸ getWorkspaceLayout(tree): Object

Returns workspace defaults. It includes defaults folders for apps and libs, and the default scope.

Example:

1{ appsDir: 'apps', libsDir: 'libs', npmScope: 'myorg' }

Parameters

Returns

Object

getWorkspacePath

▸ getWorkspacePath(tree): "/angular.json" | "/workspace.json" | null

Parameters

Returns

"/angular.json" | "/workspace.json" | null

installPackagesTask

▸ installPackagesTask(tree, alwaysRun?, cwd?, packageManager?): void

Runs npm install or yarn install. It will skip running the install if package.json hasn't changed at all or it hasn't changed since the last invocation.

Parameters

Returns

void

isStandaloneProject

▸ isStandaloneProject(tree, project): boolean

Returns if a project has a standalone configuration (project.json).

Parameters

Returns

boolean

joinPathFragments

▸ joinPathFragments(...fragments): string

Normalized path fragments and joins them

Parameters

Returns

string

moveFilesToNewDirectory

▸ moveFilesToNewDirectory(tree, oldDir, newDir): void

Analogous to cp -r oldDir newDir

Parameters

Returns

void

names

▸ names(name): Object

Util function to generate different strings based off the provided name.

Examples:

1names('my-name'); // {name: 'my-name', className: 'MyName', propertyName: 'myName', constantName: 'MY_NAME', fileName: 'my-name'}
2names('myName'); // {name: 'myName', className: 'MyName', propertyName: 'myName', constantName: 'MY_NAME', fileName: 'my-name'}

Parameters

Returns

Object

normalizePath

▸ normalizePath(osSpecificPath): string

Coverts an os specific path to a unix style path

Parameters

Returns

string

offsetFromRoot

▸ offsetFromRoot(fullPathToDir): string

Calculates an offset from the root of the workspace, which is useful for constructing relative URLs.

Examples:

1offsetFromRoot('apps/mydir/myapp/'); // returns "../../../"

Parameters

Returns

string

parseJson

▸ parseJson<T>(input, options?): T

Parses the given JSON string and returns the object the JSON content represents. By default javascript-style comments are allowed.

Type parameters

Parameters

Returns

T

Object the JSON content represents

parseTargetString

▸ parseTargetString(targetString): Target

Parses a target string into {project, target, configuration}

Examples:

1parseTargetString('proj:test'); // returns { project: "proj", target: "test" }
2parseTargetString('proj:test:production'); // returns { project: "proj", target: "test", configuration: "production" }

Parameters

Returns

Target

readCachedProjectGraph

▸ readCachedProjectGraph(): ProjectGraph

Synchronously reads the latest cached copy of the workspace's ProjectGraph.

throws {Error} if there is no cached ProjectGraph to read from

Returns

ProjectGraph

readJson

▸ readJson<T>(tree, path, options?): T

Reads a json file, removes all comments and parses JSON.

Type parameters

Parameters

Returns

T

readJsonFile

▸ readJsonFile<T>(path, options?): T

Reads a JSON file and returns the object the JSON content represents.

Type parameters

Parameters

Returns

T

Object the JSON content of the file represents

readNxJson

▸ readNxJson(path?): NxJsonConfiguration

Returns the contents of nx.json.

If nx.json extends another config file, it will be inlined here.

Parameters

Returns

NxJsonConfiguration

readProjectConfiguration

▸ readProjectConfiguration(tree, projectName): ProjectConfiguration

Reads a project configuration.

The project configuration is stored in workspace.json or the associated project.json file. The utility will read from either file.

throws If supplied projectName cannot be found

Parameters

Returns

ProjectConfiguration

readTargetOptions

▸ readTargetOptions<T>(__namedParameters, context): T

Reads and combines options for a given target.

Works as if you invoked the target yourself without passing any command lint overrides.

Type parameters

Parameters

Returns

T

readWorkspaceConfiguration

▸ readWorkspaceConfiguration(tree): WorkspaceConfiguration

Read general workspace configuration such as the default project or cli settings

This does not provide projects configuration, use readProjectConfiguration instead.

Parameters

Returns

WorkspaceConfiguration

removeDependenciesFromPackageJson

▸ removeDependenciesFromPackageJson(tree, dependencies, devDependencies, packageJsonPath?): GeneratorCallback

Remove Dependencies and Dev Dependencies from package.json

For example:

1removeDependenciesFromPackageJson(tree, ['react'], ['jest']);

This will remove react and jest from the dependencies and devDependencies sections of package.json respectively.

Parameters

Returns

GeneratorCallback

Callback to uninstall dependencies only if necessary. undefined is returned if changes are not necessary.

removeProjectConfiguration

▸ removeProjectConfiguration(tree, projectName): void

Removes the configuration of an existing project.

The project configuration is stored in workspace.json or the associated project.json file. The utility will update either file.

Parameters

Returns

void

reverse

▸ reverse(graph): ProjectGraph

Returns a new project graph where all the edges are reversed.

For instance, if project A depends on B, in the reversed graph B will depend on A.

Parameters

Returns

ProjectGraph

runExecutor

▸ runExecutor<T>(targetDescription, options, context): Promise<AsyncIterableIterator<T>>

Loads and invokes executor.

This is analogous to invoking executor from the terminal, with the exception that the params aren't parsed from the string, but instead provided parsed already.

Apart from that, it works the same way:

• it will load the workspace configuration
• it will resolve the target
• it will load the executor and the schema
• it will load the options for the appropriate configuration
• it will run the validations and will set the default
• and, of course, it will invoke the executor

Example:

1for await (const s of await runExecutor(
2  { project: 'myproj', target: 'serve' },
3  { watch: true },
4  context
5)) {
6  // s.success
7}

Note that the return value is a promise of an iterator, so you need to await before iterating over it.

Type parameters

Parameters

Returns

Promise<AsyncIterableIterator<T>>

serializeJson

▸ serializeJson<T>(input, options?): string

Serializes the given data to a JSON string. By default the JSON string is formatted with a 2 space intendation to be easy readable.

Type parameters

Parameters

Returns

string

the formatted JSON representation of the object

stripIndents

▸ stripIndents(strings, ...values): string

Removes indents, which is useful for printing warning and messages.

Example:

1stripIndents`
2 Options:
3 - option1
4 - option2
5`;

Parameters

Returns

string

stripJsonComments

▸ Const stripJsonComments(text, replaceCh?): string

Takes JSON with JavaScript-style comments and remove them. Optionally replaces every none-newline character of comments with a replaceCharacter

Parameters

Returns

string

targetToTargetString

▸ targetToTargetString(target): string

Returns a string in the format "project:target[:configuration]" for the target

Parameters

Returns

string

toJS

▸ toJS(tree): void

Rename and transpile any new typescript files created to javascript files

Parameters

Returns

void

updateJson

▸ updateJson<T, U>(tree, path, updater, options?): void

Updates a JSON value to the file system tree

Type parameters

Parameters

Returns

void

updateProjectConfiguration

▸ updateProjectConfiguration(tree, projectName, projectConfiguration): void

Updates the configuration of an existing project.

The project configuration is stored in workspace.json or the associated project.json file. The utility will update either files.

Parameters

Returns

void

updateTsConfigsToJs

▸ updateTsConfigsToJs(tree, options): void

Parameters

Returns

void

updateWorkspaceConfiguration

▸ updateWorkspaceConfiguration(tree, workspaceConfig): void

Update general workspace configuration such as the default project or cli settings.

This does not update projects configuration, use updateProjectConfiguration or addProjectConfiguration instead.

Parameters

Returns

void

visitNotIgnoredFiles

▸ visitNotIgnoredFiles(tree, dirPath?, visitor): void

Utility to act on all files in a tree that are not ignored by git.

Parameters

Returns

void

workspaceLayout

▸ workspaceLayout(): Object

Returns information about where apps and libs will be created.

Returns

Object

writeJson

▸ writeJson<T>(tree, path, value, options?): void

Writes a JSON value to the file system tree

Type parameters

Parameters

Returns

void

writeJsonFile

▸ writeJsonFile<T>(path, data, options?): void

Serializes the given data to JSON and writes it to a file.

Type parameters

Parameters

Returns

void