@smartthings/dynamodb-context-store

    2.1.1 • Public • Published

    Javascript DynamoDB Context Store

    Used by the SmartApp SDK to store IDs and access tokens for an installed instance of a SmartApp and retrieves that information for use in asynchronous API calls. The use of a context store is only needed when SmartApps have to call the SmartThings API in response to external events. SmartApps that only response to lifecycle events from the SmartThings platform will automatically have the proper context without the app having to store it.

    The context stored by this module consists of the following data elements:

    • installedAppId: the UUID of the installed app instance. This is the primary key of the table.
    • locationId: the UUID of the location in which the app is installed
    • authToken: the access token used in calling the API
    • refreshToken: the refresh token used in generating a new access token when one expires
    • config: the current installed app instance configuration, i.e. selected devices, options, etc.

    Note: Version 2.X.X is a breaking change to version 1.X.X as far as configuring the context store is concerned, but either one can be used with any version of the SmartThings SDK.

    Installation

    npm install @smartthings/dynamodb-context-store

    Usage

    Create a DynamoDBContextStore object and pass it to the SmartApp connector to store the context in a table named "smartapp" in the us-east-1 AWS region. If the table does not exist it will be created.

    smartapp.contextStore(new DynamoDBContextStore())

    The more extensive set of options are shown in this example:

    smartapp.contextStore(new DynamoDBContextStore(
        {
            table: {
                name: 'custom-table',   // defaults to 'smartapp'
                hashKey: 'key1',        // defaults to 'id'
                prefix: 'context',      // defaults to 'ctx'
                readCapacityUnits: 10,  // defaults to 5, applies to automatic creation only
                writeCapacityUnits: 10  // defaults to 5, applies to automatic creation only
            },
            AWSRegion: 'us-east-2',     // defaults to 'us-east-1'
            autoCreate: true            // defaults to true
        }
    ))

    The table configuration options are:

    • name -- The name of the DynamoDB table storing the context
    • hashKey -- The name of the partition key of the table
    • prefix -- A string pre-pended to the installed app ID and used as the partition key for the entry
    • readCapacityUnits -- Number of consistent reads per second. Used only when table is created
    • writeCapacityUnits -- Number of writes per second. Used only when table is created
    • sortKey -- Optional sort key definition (see below for more details)

    Other configuration options are:

    • AWSRegion -- The AWS region containing the table
    • AWSConfigPath -- The location of the AWS configuration JSON file
    • AWSConfigJSON -- The AWS credentials and region
    • autoCreate -- Controls whether table is created if it doesn't already exist

    Note that only one of the AWS options should be specified or behavior will be inconsistent

    AWS Configuration Options

    By default, the AWS credentials are picked up from the environment. If you prefer you can read the credentials from a file with this configuration:

    smartapp.contextStore(new DynamoDBContextStore(
        {
            AWSConfigPath: './path/to/file.json'
        }
    ))

    You can also explicitly set the credentials in this way:

    smartapp.contextStore(new DynamoDBContextStore(
        {
            AWSConfigJSON: {
                accessKeyId: '<YOUR_ACCESS_KEY_ID>',
                secretAccessKey: '<YOUR_SECRET_ACCESS_KEY>',
                region: 'us-east-2'
            }
        }
    ))

    Sort Key Configuration

    In order to support single table schemas, the context store can be configured to use a table with a sort key. The simplest way to do that is by specifying the sort key name:

    smartapp.contextStore(new DynamoDBContextStore(
        {
            table: {
                name: 'my-application',
                hashKey: 'pk', 
                sortKey: 'sk'
            }
        }
    ))

    More control over the sort key can be exercised using this form, which is configured with the default values used when just the sort key name is specified:

    smartapp.contextStore(new DynamoDBContextStore(
        {
            table: {
                name: 'my-application',
                hashKey: 'pk', 
                sortKey: {
                    AttributeName: 'sk',
                    AttributeType: 'S',
                    AttributeValue: 'context',
                    KeyType: 'RANGE'
                }
            }
        }
    ))

    Install

    npm i @smartthings/dynamodb-context-store

    DownloadsWeekly Downloads

    11

    Version

    2.1.1

    License

    Apache-2.0

    Unpacked Size

    35.7 kB

    Total Files

    15

    Last publish

    Collaborators

    • john-u
    • dianoga
    • workmonk
    • xres
    • bflorian
    • erode
    • smartthingspi
    • rossiam
    • jodyalbritton