parameter-store-task

This lambda function is designed to get and put parameters from AWS Parameter Store for AWS Step Functions. The step functions will invoke the lambda based on the input event and state machine definition. This function should allow for

1. Getting a parameter, multiple parameters or parameters by path
2. Putting a single parameter or multiple parameters

Required AWS Resources

AWS Parameter Store

Required Permissions

• ssm:GetParameter
• ssm:GetParameters
• ssm:GetParametersByPath
• ssm:PutParameter

Request Syntax

The event is passed in as a JSON object. Examples:

{
  "GetParameter": {
    "Name": "string",
    "ResultFormat": "string"
  }
}

{
  "GetParameters": {
    "Names": ["string"],
    "ResultFormat": "string"
  }
}

{
  "GetParametersByPath": {
    "Path": "string",
    "Recursive": boolean,
    "RelativePath": boolean,
    "ResultFormat": "string"
  }
}

{
  "PutParameter": {
    "Name": "string",
    "Value": "string" | ["string"],
    "Description": "string",
    "Secure": booleran,
    "KeyId": "string",
    "Overwrite": boolean,
  }
}

GetParameter

Name:	The name of the parameter to get. REQUIRED
ResultFormat:	The format of the result. VALUE_ONLY, NAME_VALUE, or NESTED_MAP. OPTIONAL, defaults to NAME_VALUE.

GetParameters

Names:	The names of the parameter to get. REQUIRED
ResultFormat:	The format of the result. NAME_VALUE or NESTED_MAP. OPTIONAL, defaults to NAME_VALUE.

GetParametersByPath

Path:	The path of the parameters to get. REQUIRED
Recursive:	Whether to recurse through the parameter tree, starting at Path. OPTIONAL - defaults to false
RelativePath:	If true, will remove the path provided from the names returned. OPTIONAL, defaults to false.
ResultFormat:	The format of the result. NAME_VALUE, NESTED_MAP. OPTIONAL, defaults to NAME_VALUE.

PutParameter

Name:	The name of the parameter to put. REQUIRED
Value:	The value of the parameter to put. If this is an [] then the type StringList will be used. REQUIRED
Description:	The description of the parameter. OPTIONAL, defaults to empty string.
Secure:	true if this parameter should be a SecureString. OPTIONAL, defaults to false.
KeyId:	The AWS KMS Key Id to use to encrypt the parameter if Secure=true. OPTIONAL, defaults to the account key for parameter encryption.
Overwrite:	true if existing parameters should be overwritten. OPTIONAL, defaults to false.

Result Formats

VALUE_ONLY

Only the value of the parameter will be returned. For example:

"MyValue"

NAME_VALUE

The name and value of the parameter(s) will be returned in a flat map. For example:

{
  "MyName": "MyValue",
  "path/to/MyName": "MyValue"
}

NESTED_MAP

The names of the parameters will be split by /, with each sub-name becoming a map in the nested map returned. For example:

{
  "MyName": "MyValue",
  "path": {
    "to": {
      "MyName": "MyValue"
    }
  }
}

Behavior

GetParameter, GetParameters, GetParametersByPath

• If the parameter value is of type StringList then a ["string"] will be returned.

GetParameters, GetParametersByPath

• If the path contains a node that both has a value and has children and the ResultFormat is NESTED_MAP then a ValueError is raised.

GetParametersByPath

• If RelativePath is set to true the the path removed will be up to and including the last occurance of /.

PutParameter

• If Value is a ["string"] then a StringList will be created unless Secure is true, in which case a SecureString will be created.

Response Syntax

For GetParameter and GetParameters and GetParametersByPath see Result Formats above.

For PutParameter, the version number is returned:

123

License: APL2