Golem Application Manifest Reference
JSON schema
For the application manifest format we also publish JSON schemas. The current version (1.1.1) is available here (opens in a new tab).
The JSON schema is intended to be used with editors and IDEs, to help with base validation and code completion.
Use the following YAML comments at the start of your golem.yaml documents to enable schema support:
# $schema: https://schema.golem.cloud/app/golem/1.1.1/golem.schema.jsonNote that on top of the above schema there are other checks performed by golem-cli, see the field reference below for details.
Loading of Application Manifest documents
The Golem CLI commands that use Application Manifest start by searching for golem.yaml documents in the current and the parent directories. Once the top level manifest document is found, more manifests are searched based on the includes fields.
After resolving relative paths in the documents they are merged, then component selection happens: this can be either explicit, by using --component-name CLI flags, or implicit, in which case only components defined in the directory - including subdirectories - from where the Golem CLI was executed are used.
Application Manifest documents can also be explicitly passed to the CLI, using the --app flag. Note that when using explicit documents the includes field is not used, it is expected that all relevant documents are provided for the CLI.
Build steps performed by the App Build command
The golem-cli app build command can be used to create Golem components. The command relies on build steps implemented partially in golem-cli and partially defined by the component specific build properties.
There are three main build steps.
gen-rpc:
- Generates required client WIT packages for Worker to Worker communication based on
components.<component-name>.sourceWitanddependencies. - In case of
static-wasm-rpcdependencies it also generates and builds the required client components. - Generates
components.<component-name>.generatedWit. usingcomponents.<component-name>.sourceWit,dependenciesandwitDeps.
componentize:
Builds the component using steps defined in components.<component-name>.build.
The final binary should be created at components.<component-name>.componentWasm.
Usually the steps involve binding generation from
link-rpc:
Links the componentized WASM binary with required client components. For static-wasm-rpc this means the client
components generated during gen-rpc, for wasm-rpc these will be skipped, as the clients are generated dynamically
on the server-side.
By default, all the above three steps are executed when using golem-cli app build, but they can be selected by using the
--step flag. This is intended to be used for more complex setups, when one would like to integrate golem-cli app build
into another build tool.
Template variables and functions
The Application Manifest has some fields which are used as templates, these fields are marked as Templated in the field reference below. The templates are using minijinja (opens in a new tab), which is a minimal templating engine based on Jinja2 syntax.
Available template variables:
component_name: contains the current component name in which the template is used
Available naming related string transforming functions:
to_snake_caseto_kebab_caseto_lower_camel_caseto_pascal_caseto_shouty_kebab_caseto_shouty_snake_caseto_snake_caseto_title_caseto_train_caseto_upper_camel_case
build: tool-name build {{ component_name | to_snake_case }}.wasmField reference
includes
Optional list of glob patterns that are used for adding search patterns for other Application Manifests when using auto discovery of them. The patterns are relative to the manifest document in which they are defined.
The default search pattern is **/golem.yaml, which searches for golem.yaml documents in every subdirectory
recursively. Templates and examples provided by Golem usually use more specific search patterns to make the lookups
more efficient.
The includes fields can be defined in one manifest only, usually in the project root directory.
Defining it multiple times results in validation error.
includes:
- components-dir/*/golem.yaml
- custom-templates/golem-*.yamltempDir
Optional path that overrides the default path of the default temporary directory (golem-temp) which is
used
for storing various intermediate artifacts.
The path is relative to the manifest document in which they are defined.
tempDir: target/golem-tempwitDeps
Optional list of paths of directories where WIT dependency packages can be stored. The paths are relative to the manifest document in which they are defined.
During component WIT generation these paths are checked for resolving missing dependencies. It is intended to be used for eliminating duplication of common dependencies and interfaces.
The witDeps fields can be defined in one manifest only, usually in the project root directory.
Defining it multiple times results in validation error.
witDeps:
- wit-common/depscomponents
Optional map of Golem components indexed by component-name-s used for defining components.
The components field can be defined in multiple manifest documents, but the used component-name-s must be
unique across all the used manifest documents. Using the same component-name more then once results in
validation error.
components:
pack-ns:component-name:
sourceWit: # ...
# ...
pack:comp-b:
sourceWit: # ...
# ...components.<component-name>.template
Optional template name which will be used for creating the component fields.
The template name must be one of that are defined in templates.
See templates and Template variable and functions
for defining templates.
components.<component-name>.componentType
Optional string enum of component types, accepted values:
durable(default value)available sinceJSON Schema:1.1.0|OSS CLI: 1.1.0|Cloud CLI: 1.1.0ephemeralavailable sinceJSON Schema:1.1.0|OSS CLI: 1.1.0|Cloud CLI: 1.1.0
See Ephemeral vs Durable Workers for more information about component types.
components:
pack-ns:component-name:
# ...
componentType: durable
pack-ns:component-name:
# ...
componentType: ephemeralcomponents.<component-name>.files
Optional list of files entries, which can be used for defining the Initial File System for the component.
components:
pack-ns:component-name:
# ...
files:
- sourcePath: ./files/foo.txt
targetPath: /files/foo.txt
permissions: read-only
- sourcePath: ./files/bar.txt
targetPath: /files/bar.txt
permissions: read-writecomponents.<component-name>.files[*].sourcePath
Required source path of the file to be added to the Initial File System. The path can be a file path relative to the manifest document or an URL.
components.<component-name>.files[*].targetPath
Required target path of the file in the Initial File System. The path must be an absolute path.
components.<component-name>.files[*].permissions
Optional string enum which controls file permissions. Accepted values:
read-only(default value)available sinceJSON Schema:1.1.0|OSS CLI: 1.1.0|Cloud CLI: 1.1.0read-writeavailable sinceJSON Schema:1.1.0|OSS CLI: 1.1.0|Cloud CLI: 1.1.0
components.<component-name>.sourceWit
Required directory path for the user defined component WIT directory.
The path is relative to the manifest document in which the field is defined.
The WIT directory can omit the deps folder if the required dependencies are
available in some of the folders defined in witDeps.
components:
pack-ns:component-name:
# ...
sourceWit: witcomponents.<component-name>.generatedWit
Required directory path for the generated WIT directory created by the golem tooling, which handles exported interface extraction and includes resolved package and client dependencies.
This directory is intended to be used as source for binding generation.
The path is relative to the manifest document in which the field is defined.
This folder is usually added to .gitignore, as it is generated as part of build.
components:
pack-ns:component-name:
# ...
generatedWit: wit-generatedcomponents.<component-name>.componentWasm
Required file path which should point to the built component WASM file before linking.
The path is relative to the manifest document in which the field is defined.
This file is usually added to .gitignore, as it is created as part of build.
components:
pack-ns:component-name:
# ...
componentWasm: build/component.wasmcomponents.<component-name>.linkedWasm
Optional file path which should point to the built component WASM file after linking.
Defaults to golem-temp/linked-wasm/component-name.wasm, see tempDir.
The path is relative to the manifest document in which the field is defined.
This file is usually added to .gitignore, as it is created as part of build.
components:
pack-ns:component-name:
# ...
linkedWasm: golem-temp/component/component.wasmcomponents.<component-name>.build
Optional list of build commands that creates components.<component-name>.componentWasm.
components:
pack-ns:component-name:
build:
- command: bindgen-tool wit-generated
- command: build-tool wit-generated component.wasmcomponents.<component-name>.build[*].command
Required external command that will be used as a build step for creating
components.<component-name>.componentWasm.
components.<component-name>.build[*].dir
Optional directory path which will be used as working directory when executing
components.<component-name>.build[*].command.
The path is relative to the manifest document, and defaults to ..
components.<component-name>.build[*].rmdirs
Optional list of directory paths which will be deleted before executing the command.
The path is relative to components.<component-name>.build[*].dir.
The rmdirs field is useful when a binding generator does not automatically clean stale bindings.
Directories are not removed if the command is skipped because of up-to-date checks, see
components.<component-name>.build[*].sources and
components.<component-name>.build[*].targets.
Directories are removed before executing components.<component-name>.build[*].mkdirs.
components.<component-name>.build[*].mkdirs
Optional list of directory paths which will be created before executing the command if they do not exists.
The path is relative to components.<component-name>.build[*].dir.
The mkdirs field is useful when a build of binding generator tool does not automatically create
required nested folders.
Directories are not created if the command is skipped because of up-to-date checks, see
components.<component-name>.build[*].sources and
components.<component-name>.build[*].targets.
Directories are created after executing components.<component-name>.build[*].rmdirs.
components.<component-name>.build[*].sources
Optional list of paths and globs which are used as sources for performing up-to-date checks.
If defined then components.<component-name>.build[*].targets also have to be used.
The up-to-date check
- skips executing
components.<component-name>.build[*].command - if all matching files defined by
components.<component-name>.build[*].targets - are newer then the matched files defined by
sources.
components:
pack-ns:component-name:
# ...
build:
- command: build-tool src-dir out.wasm
sources:
- src-dir/*
targets:
- out.wasmcomponents.<component-name>.build[*].targets
Optional list of paths and globs which are used as targets for performing up-to-date checks.
If defined then components.<component-name>.build[*].sources also have to be used.
See components.<component-name>.build[*].sources for up-to-date check details.
components.<component-name>.customCommands
Optional map of component specific external commands, which are useful for defining e.g. one time installation or update related commands for the component.
The commands can be executed using:
golem-cli app command-nameMultiple components can use the same command-name, the above command will execute all matching
commands in this case, both component specific and project ones.
For defining project level custom commands see customCommands.
The following command names cannot be used, as they are used by golem-cli app itself:
buildclean
components:
pack-ns:component-name:
# ...
customCommands:
npm-install:
- command: npm installcomponents.<component-name>.customCommands.<command-name>[*].dir
Component specific customCommands.<command-name>[*].dir.
components.<component-name>.customCommands.<command-name>[*].rmdirs
Component specific customCommands.<command-name>[*].rmdirs.
components.<component-name>.customCommands.<command-name>[*].mkdirs
Component specific customCommands.<command-name>[*].mkdirs.
components.<component-name>.customCommands.<command-name>[*].mkdirs
Component specific customCommands.<command-name>[*].mkdirs.
components.<component-name>.customCommands.<command-name>[*].sources
Component specific customCommands.<command-name>[*].sources.
components.<component-name>.customCommands.<command-name>[*].targets
Component specific customCommands.<command-name>[*].targets.
components.<component-name>.clean
components.<component-name>.profiles
Optional map of profiles, which can be used to provide multiple build profiles for a component, typically used for debug and release configurations.
A profile contains the same fields as a component, expect for defaultProfile and profile itself.
When profiles are defined for a component:
components.<component-name>.defaultProfilemust be defined,- non-profile component fields should not be used on the component, apart from
defaultProfile.
When building, by default golem-cli will use defaultProfile, unless a specific profile is requested and_
the component has a matching profile. E.g. the following command:
golem-cli app --build-profile release build- will build components that have no profiles by using the non-profile component fields
- will use the
releaseprofile for components that are usingprofilesand have a profile namedrelease - will use the
defaultProfilefor components that usingprofiles, but do not have a profile namedrelease
components:
pack-ns:component-name:
profiles:
debug:
build:
- command: build-tool --debug out.wasm
release:
build:
- command: build-tool --release out.wasm
defaultProfile: releasecomponents.<component-name>.defaultProfile
Optional profile name that defines which profile should be used.
It must be defined when using components.<component-name>.profiles, and must be one of the
profile names defined there.
components.<component-name>.profiles.<profile-name>.componentType
Profile specific components.<component-name>.componentType.
components.<component-name>.profiles.<profile-name>.files
Profile specific components.<component-name>.files.
components.<component-name>.profiles.<profile-name>.files[*].sourcePath
Profile specific components.<component-name>.files[*].sourcePath.
components.<component-name>.profiles.<profile-name>.files[*].targetPath
Profile specific components.<component-name>.files[*].targetPath.
components.<component-name>.profiles.<profile-name>.files[*].permissions
Profile specific components.<component-name>.files[*].permissions.
components.<component-name>.profiles.<profile-name>.sourceWit
Profile specific components.<component-name>.sourceWit.
components.<component-name>.profiles.<profile-name>.generatedWit
Profile specific components.<component-name>.generatedWit.
components.<component-name>.profiles.<profile-name>.componentWasm
Profile specific components.<component-name>.componentWasm.
components.<component-name>.profiles.<profile-name>.linkedWasm
Profile specific components.<component-name>.linkedWasm.
components.<component-name>.profiles.<profile-name>.build
Profile specific components.<component-name>.build.
components.<component-name>.profiles.<profile-name>.build[*].command
Profile specific components.<component-name>.build[*].command.
components.<component-name>.profiles.<profile-name>.build[*].dir
Profile specific components.<component-name>.build[*].dir.
components.<component-name>.profiles.<profile-name>.build[*].rmdirs
Profile specific components.<component-name>.build[*].rmdirs.
components.<component-name>.profiles.<profile-name>.build[*].mkdirs
Profile specific components.<component-name>.build[*].mkdirs.
components.<component-name>.profiles.<profile-name>.build[*].sources
Profile specific components.<component-name>.build[*].sources.
components.<component-name>.profiles.<profile-name>.build[*].targets
Profile specific components.<component-name>.build[*].targets.
components.<component-name>.profiles.<profile-name>.customCommands
Profile specific components.<component-name>.customCommands.
components.<component-name>.profiles.<profile-name>.customCommands.<command-name>[*].dir
Profile specific components.<component-name>.customCommands.<command-name>[*].dir.
components.<component-name>.profiles.<profile-name>.customCommands.<command-name>[*].rmdirs
Profile specific components.<component-name>.customCommands.<command-name>[*].rmdirs.
components.<component-name>.profiles.<profile-name>.customCommands.<command-name>[*].mkdirs
Profile specific components.<component-name>.customCommands.<command-name>[*].mkdirs.
components.<component-name>.profiles.<profile-name>.customCommands.<command-name>[*].mkdirs
Profile specific components.<component-name>.customCommands.<command-name>[*].mkdirs.
components.<component-name>.profiles.<profile-name>.customCommands.<command-name>[*].sources
Profile specific components.<component-name>.customCommands.<command-name>[*].sources.
components.<component-name>.profiles.<profile-name>.customCommands.<command-name>[*].targets
Profile specific components.<component-name>.customCommands.<command-name>[*].targets.
components.<component-name>.profiles.<profile-name>.clean
Profile specific components.<component-name>.clean.
dependencies
Optional map of list of component dependencies, which can be used for defining WASM RPC connections between components.
components:
pack-ns:component-a:
# ...
pack-ns:component-b:
# ...
pack-ns:component-c:
# ...
dependencies:
pack-ns:component-a:
- target: pack-ns:component-b
type: wasm-rpc
- target: pack-ns:component-c
type: wasm-rpc
pack-ns:component-b:
- target: pack-ns:component-a
type: wasm-rpc
- target: pack-ns:component-b
type: wasm-rpcdependencies.<component-name>[*].type
Required string enum, accepted values:
wasm-rpcavailable sinceJSON Schema:1.1.0|OSS CLI: 1.1.0|Cloud CLI: 1.1.0Dynamic WASM RPC linking. The preferred method for linking.
With this dependency type the linking happens on servers side, so there is no need for generating and creating WAM RPC clients.
static-wasm-rpcavailable sinceJSON Schema:1.1.2|OSS CLI: 1.1.12|Cloud CLI: 1.1.2Static WASM RPC linking.
With this dependency type the linking happens locally, so it requires Rust tooling.
dependencies.<component-name>[*].target
Required component-name, which defines the target of the dependency.
Must be a defined component name.
clean
Optional list of paths which are added as targets to the golem-cli app clean command.
The paths are relative to the manifest document.
The clean command deletes the following paths:
-
tempDir -
components.<component-name>.generatedWit -
components.<component-name>.linkedWasm - build and custom command
targets - the paths defined in common and component specific
cleanfields.
Related fields:
customCommands
Optional map of custom external commands, which are useful for defining e.g. one time installation or update related project commands.
The commands can be executed using:
golem-cli app command-nameComponents specific custom commands can use the same command-name, the above command will execute all matching
commands in this case, both component specific and project ones.
For defining component specific custom commands see components.<component-name>.customCommands.
The following command names cannot be used, as they are used by golem-cli app itself:
buildclean
customCommands:
npm-install:
- command: npm installcustomCommands.<command-name>[*].dir
Optional directory path which will be used as working directory when executing
customCommands.<command-name>[*].command.
The path is relative to the manifest document, and defaults to ..
customCommands.<command-name>[*].rmdirs
Optional list of directory paths which will be deleted before executing the command.
The path is relative to customCommands.<command-name>[*].dir.
The rmdirs field is useful when a binding generator does not automatically clean stale bindings.
Directories are not removed if the command is skipped because of up-to-date checks, see
customCommands.<command-name>[*].sources and
customCommands.<command-name>[*].targets.
Directories are removed before executing customCommands.<command-name>[*].mkdirs.
customCommands.<command-name>[*].mkdirs
Optional list of directory paths which will be created before executing the command if they do not exists.
The path is relative to customCommands.<command-name>[*].dir.
The mkdirs field is useful when a build of binding generator tool does not automatically create
required nested folders.
Directories are not created if the command is skipped because of up-to-date checks, see
customCommands.<command-name>[*].sources and
customCommands.<command-name>[*].targets.
Directories are created after executing customCommands.<command-name>[*].rmdirs.
customCommands.<command-name>[*].sources
Optional list of paths and globs which are used as sources for performing up-to-date checks.
If defined then customCommands.<command-name>[*].targets also have to be used.
The up-to-date check
- skips executing
customCommands.<command-name>[*].command - if all matching files defined by
customCommands.<command-name>[*].targets - are newer then the matched files defined by
sources.
customCommands.<command-name>[*].targets
Optional list of paths and globs which are used as targets for performing up-to-date checks.
If defined then customCommands.<command-name>[*].sources also have to be used.
See customCommands.<command-name>[*].sources for up-to-date check details.
templates
Optional map of named templates, which can be used in components.<component-name>.template.
Templates help in extracting common build patterns and reuse them for multiple components.
The templates field can be defined in multiple application manifest documents, but the template names must be
unique.
See Template variable and functions for more information about templating.
templates:
my-template:
sourceWit: wit
componentWasm: build/{{component_name | to_snake_case}}
# ...
my-template-with-profiles:
profiles:
debug:
# ...
release:
# ...
components:
pack-ns:component-a:
template: my-template
pack-ns:component-b:
template: my-template
sourceWit: custom-wit # override
pack-ns:component-c:
template: my-template-with-profiles
profiles:
debug:
sourceWit: custom-wit # overridetemplates.<template-name>.componentType
Templated components.<component-name>.componentType.
templates.<template-name>.files
Templated components.<component-name>.files.
templates.<template-name>.files[*].sourcePath
templates.<template-name>.files[*].targetPath
templates.<template-name>.files[*].permissions
templates.<template-name>.sourceWit
Templated components.<component-name>.sourceWit.
templates.<template-name>.generatedWit
Templated components.<component-name>.generatedWit.
templates.<template-name>.componentWasm
Templated components.<component-name>.componentWasm.
templates.<template-name>.linkedWasm
Templated components.<component-name>.linkedWasm.
templates.<template-name>.build
Templated components.<component-name>.build.
templates.<template-name>.build[*].command
Templated components.<component-name>.build[*].command.
templates.<template-name>.build[*].dir
Templated components.<component-name>.build[*].dir.
templates.<template-name>.build[*].rmdirs
Templated components.<component-name>.build[*].rmdirs.
templates.<template-name>.build[*].mkdirs
Templated components.<component-name>.build[*].mkdirs.
templates.<template-name>.build[*].sources
Templated components.<component-name>.build[*].sources.
templates.<template-name>.build[*].targets
Templated components.<component-name>.build[*].targets.
templates.<template-name>.customCommands
Templated components.<component-name>.customCommands.
templates.<template-name>.customCommands.<command-name>[*].dir
Templated components.<component-name>.customCommands.<command-name>[*].dir.
templates.<template-name>.customCommands.<command-name>[*].rmdirs
Templated components.<component-name>.customCommands.<command-name>[*].rmdirs.
templates.<template-name>.customCommands.<command-name>[*].mkdirs
Templated components.<component-name>.customCommands.<command-name>[*].mkdirs.
templates.<template-name>.customCommands.<command-name>[*].mkdirs
Templated components.<component-name>.customCommands.<command-name>[*].mkdirs.
templates.<template-name>.customCommands.<command-name>[*].sources
Templated components.<component-name>.customCommands.<command-name>[*].sources.
templates.<template-name>.customCommands.<command-name>[*].targets
Templated components.<component-name>.customCommands.<command-name>[*].targets.
templates.<template-name>.clean
Templated components.<component-name>.clean.
templates.<template-name>.profiles
Templated components.<component-name>.profiles.
templates.<template-name>.profiles.<profile-name>
Templated components.<component-name>.profiles.<profile-name>.
templates.<template-name>.profiles.<profile-name>.componentType
Templated and profile specific components.<component-name>.componentType.
templates.<template-name>.profiles.<profile-name>.files
Templated and profile specific components.<component-name>.files.
templates.<template-name>.profiles.<profile-name>.files[*].sourcePath
Templated and profile specific components.<component-name>.files[*].sourcePath.
templates.<template-name>.profiles.<profile-name>.files[*].targetPath
Templated and profile specific components.<component-name>.files[*].targetPath.
templates.<template-name>.profiles.<profile-name>.files[*].permissions
Templated and profile specific components.<component-name>.files[*].permissions.
templates.<template-name>.profiles.<profile-name>.sourceWit
Templated and profile specific components.<component-name>.sourceWit.
templates.<template-name>.profiles.<profile-name>.generatedWit
Templated and profile specific components.<component-name>.generatedWit.
templates.<template-name>.profiles.<profile-name>.componentWasm
Templated and profile specific components.<component-name>.componentWasm.
templates.<template-name>.profiles.<profile-name>.linkedWasm
Templated and profile specific components.<component-name>.linkedWasm.
templates.<template-name>.profiles.<profile-name>.build
Templated and profile specific components.<component-name>.build.
templates.<template-name>.profiles.<profile-name>.build[*].command
Templated and profile specific components.<component-name>.build[*].command.
templates.<template-name>.profiles.<profile-name>.build[*].dir
Templated and profile specific components.<component-name>.build[*].dir.
templates.<template-name>.profiles.<profile-name>.build[*].rmdirs
Templated and profile specific components.<component-name>.build[*].rmdirs.
templates.<template-name>.profiles.<profile-name>.build[*].mkdirs
Templated and profile specific components.<component-name>.build[*].mkdirs.
templates.<template-name>.profiles.<profile-name>.build[*].sources
Templated and profile specific components.<component-name>.build[*].sources.
templates.<template-name>.profiles.<profile-name>.build[*].targets
Templated and profile specific components.<component-name>.build[*].targets.
templates.<template-name>.profiles.<profile-name>.customCommands
Templated and profile specific components.<component-name>.customCommands.
templates.<template-name>.profiles.<profile-name>.customCommands.<command-name>
Templated and profile specific components.<component-name>.customCommands.<command-name>.
templates.<template-name>.profiles.<profile-name>.customCommands.<command-name>[*].dir
Templated and profile specific components.<component-name>.customCommands.<command-name>[*].dir.
templates.<template-name>.profiles.<profile-name>.customCommands.<command-name>[*].rmdirs
Templated and profile specific components.<component-name>.customCommands.<command-name>[*].rmdirs.
templates.<template-name>.profiles.<profile-name>.customCommands.<command-name>[*].mkdirs
Templated and profile specific components.<component-name>.customCommands.<command-name>[*].mkdirs.
templates.<template-name>.profiles.<profile-name>.customCommands.<command-name>[*].mkdirs
Templated and profile specific components.<component-name>.customCommands.<command-name>[*].mkdirs.
templates.<template-name>.profiles.<profile-name>.customCommands.<command-name>[*].sources
Templated and profile specific components.<component-name>.customCommands.<command-name>[*].sources.
templates.<template-name>.profiles.<profile-name>.customCommands.<command-name>[*].targets
Templated and profile specific components.<component-name>.customCommands.<command-name>[*].targets.
templates.<template-name>.profiles.<profile-name>.clean
Templated and profile specific components.<component-name>.clean.
templates.<template-name>.defaultProfile
String which selects the default profile for the template. Required if profiles are used. Must be one
of the defined profile names in templates.<template-name>.profiles.
templates:
rust:
profiles:
debug:
# ...
release:
# ...
defaultProfile: debugFields and changes by releases
static-wasm-rpc todependencies.<component-name>[*].type