ssmvars

README

ssmvars

Utility library to store app configuration secrets using AWS SSM Parameter Store backend.

The concept behind this library is that the VariableRepository takes "exclusive ownership" of a variable prefix, and then allows setting up multiple namespaces as well as individual variables in them.

Resulting variables thus constructed like this in Parameter Store:

/${prefix}/variables/${namespace}/${variable}

There are two types of variables - plain (read-write) and secret (write-only). The latter type is implemented using SecureString - to manage those, you will need to provide a valid KMS key ID for the library to use.

Documentation

Index

• func Environment(ctx context.Context, reader Reader, namespace string) ([]string, error)
• type ReadWriter
  • func New(client ssmiface.SSMAPI, prefix, kmsKeyID string) ReadWriter
• type Reader
  • func NewReader(client ssmiface.SSMAPI, prefix string) Reader
• type Variable
• type Writer
  • func NewWriter(client ssmiface.SSMAPI, prefix, kmsKeyID string) Writer

Functions

func Environment

func Environment(ctx context.Context, reader Reader, namespace string) ([]string, error)

Environment is a convenience function presenting the content of a Reader in a way that's compatible with operations that expect os.Environment.

Types

type ReadWriter

type ReadWriter interface {
	Reader
	Writer
}

ReadWriter is a 'read-write' proxy to variables stored in SSM.

func New

func New(client ssmiface.SSMAPI, prefix, kmsKeyID string) ReadWriter

New returns a Variables ReadWriter backed by SSM Parameter Store.

type Reader

type Reader interface {
	// ShowVariable retrieves an individual variable by its name.
	ShowVariable(ctx context.Context, namespace, name string) (*Variable, error)

	// ListVariables lists all variables for a given namespace. It does
	// pagination automatically, with 10 entries per page. In pathological
	// cases, this operation could take a while.
	ListVariables(ctx context.Context, namespace string) ([]*Variable, error)
}

Reader provides are 'read-only' proxy to variables stored in SSM.

func NewReader

func NewReader(client ssmiface.SSMAPI, prefix string) Reader

NewReader returns a Variables Reader backed by SSM Parameter Store.

type Variable

type Variable struct {
	// Name of the variable.
	Name string

	// Value of the variable.
	Value string

	// Whether the variable should be readable from the UI.
	WriteOnly bool
}

Variable represents a single configuration variable.

type Writer

type Writer interface {
	// CreateVariable creates or updates an existing variable.
	CreateVariable(ctx context.Context, namespace string, variable *Variable) (*Variable, error)

	// DeleteVariable deletes an existing variable.
	DeleteVariable(ctx context.Context, namespace, name string) (*Variable, error)

	// Reset removes all variables for a given namespace.
	Reset(ctx context.Context, namespace string) error
}

Writer provides are 'write-only' proxy to variables stored in SSM.

func NewWriter

func NewWriter(client ssmiface.SSMAPI, prefix, kmsKeyID string) Writer

NewWriter returns a Variables Writer backed by SSM Parameter Store.