The activate() function that starts the IoT Agent receives as single parameter with the configuration for the IoT
Agent. The Agent Console reads the same configuration from the config.js file.
These are the parameters that can be configured in the global section:
- logLevel: minimum log level to log. May take one of the following values: DEBUG, INFO, ERROR, FATAL. E.g.: 'DEBUG'.
- contextBroker: connection data to the Context Broker (host and port). E.g.:
{
host: '192.168.56.101',
port: '1026'
}- If you want to use NGSI v2:
{
host: '192.168.56.101',
port: '1026',
ngsiVersion: 'v2'
}- If you want to use NGSI-LD (experimental):
{
host: '192.168.56.101',
port: '1026',
ngsiVersion: 'ld',
jsonLdContext: 'http://context.json-ld''
}Where http://context.json-ld is the location of the NGSI-LD @context element which provides additional information allowing the computer to
interpret the rest of the data with more clarity and depth. Read the JSON-LD specification for more informtaion.
- server: configuration used to create the Context Server (port where the IoT Agent will be listening as a Context
Provider and base root to prefix all the paths). The
portattribute is required. If nobaseRootattribute is used, '/' is used by default. E.g.:
{
baseRoot: '/',
port: 4041
}- stats: configure the periodic collection of statistics. Use
intervalin milliseconds to set the time between stats writings.
stats: {
interval: 100;
}- authentication: authentication data, for use in retrieving tokens for devices with a trust token (required in
scenarios with security enabled in the Context Broker side). Currently, two authentication provider are supported:
keystoneandoauth2. Authentication need to be enabled by setting the fieldenabledtotrue. Inkeystonebased authentication, thetrustassociated to thedeviceordeviceGroupis a token representing a specific user and his rights on a given domain (i.e. combination offiware-serviceandfiware-servicepath). The authentication process use the trust delegation workflow to check if the trust provided is valid, in which case return ax-subject-tokenthat can be used to authenticate the request to the Context Broker. Required parameters are: theurlof the keystone to be used (alternativelyhostandportbut if you use this combination, the IoT Agent will assume that the protocol is HTTP), theuserandpasswordto which it is delegated thetrustverification. E.g.:
{
enabled: true,
url: 'https://localhost:5000',
type: 'keystone',
user: 'iotagent',
password: 'iotagent'
}In oauth2 based authentication, two types of tokens can be used depending on the availability in the IDM to be used.
On one hand, the trust associated to the device or deviceGroup is a refresh_token issued by a specific user for
the Context Broker client. The authentication process uses the
refresh_token grant type to obtain an access_token that can be
used to authenticate the request to the Context Broker. At the time being the assumption is that the refresh_token is
a not expiring offline_token (we believe this is the best solution in the case of IoT Devices, since injecting a
refresh token look may slow down communication. Still, the developer would be able to invalidate the refresh token on
the provider side in case of security issues connected to a token). The code was tested using
Keycloak, Auth0 and FIWARE Keyrock
(it may require customisation for other providers - while OAuth2 is a standard, not all implementations behave in the
same way, especially as regards status codes and error messages). Required parameters are: the url of the OAuth 2
provider to be used (alternatively host and port but if you use this combination, the IoT Agent will assume that the
protocol is HTTP), the tokenPath to which the validation request should be sent
(/auth/realms/default/protocol/openid-connect/token for Keycloak and Auth0, /oauth2/token for Keyrock), the
clientId and clientSecret that identify the Context Broker, and the header field that should be used to send the
authentication request (that will be sent in the form Authorization: Bearer <access_token>). E.g.:
{
enabled: true,
type: 'oauth2',
url: 'http://localhost:3000',
header: 'Authorization',
clientId: 'context-broker',
clientSecret: 'c8d58d16-0a42-400e-9765-f32e154a5a9e',
tokenPath: '/auth/realms/default/protocol/openid-connect/token'
}Nevertheless, this kind of authentication relying on refresh_token grant type implies that when the acces_token
expires, it is needed to request a new one from the IDM, causing some overhead in the communication with the Context
Broker. To mitigate this issue, FIWARE KeyRock IDM implements permanent tokens that can be retrieved using
scope=permanent. With this approach, the IOTA does not need to interact with the IDM and directly include the
permanent token in the header. In order to use this type of token, an additional parameter permanentToken must be
set to true in the authentication configuration. An environment variable IOTA_AUTH_PERMANENT_TOKEN can be also
used for the same purpose. For instance:
{
type: 'oauth2',
url: 'http://localhost:3000',
header: 'Authorization',
clientId: 'context-broker',
clientSecret: '0c2492e1-3ce3-4cca-9723-e6075b89c244',
tokenPath: '/oauth2/token',
enabled: true,
permanentToken: true
}- deviceRegistry: type of Device Registry to create. Currently, two values are supported:
memoryandmongodb. If the former is configured, a transient memory-based device registry will be used to register all the devices. This registry will be emptied whenever the process is restarted. If the latter is selected, a MongoDB database will be used to store all the device information, so it will be persistent from one execution to the other. Mongodb databases must be configured in themongobsection (as described bellow). E.g.:
{
type: 'mongodb';
}- mongodb: configures the MongoDB driver for those repositories with 'mongodb' type. If the
hostparameter is a list of comma-separated IPs, they will be considered to be part of a Replica Set. In that case, the optional propertyreplicaSetshould contain the Replica Set name. The MongoBD driver will retry the connection at startup timeretriestimes, waitingretryTimeseconds between attempts, if those attributes are present (default values are 5 and 5 respectively). E.g.:
{
host: 'localhost',
port: '27017',
db: 'iotagent',
retries: 5,
retryTime: 5
}- iotManager: configures all the information needed to register the IoT Agent in the IoTManager. If this section
is present, the IoTA will try to register to a IoTAM in the
host,portandpathindicated, with the information configured in the object. The IoTAgent URL that will be reported will be theprovidedUrl(described below) with the addedagentPath:
{
host: 'mockediotam.com',
port: 9876,
path: '/protocols',
protocol: 'GENERIC_PROTOCOL',
description: 'A generic protocol',
agentPath: '/iot'
}- types: See Type Configuration in the Configuration API section below.
- eventType: Default type for the Events (useful only with the
addEventsplugin). - service: default service for the IoT Agent. If a device is being registered, and no service information comes with the device data, and no service information is configured for the given type, the default IoT agent service will be used instead. E.g.: 'smartGondor'.
- subservice: default subservice for the IoT Agent. If a device is being registered, and no subservice information comes with the device data, and no subservice information is configured for the given type, the default IoT agent subservice will be used instead. E.g.: '/gardens'.
- providerUrl: URL to send in the Context Provider registration requests. Should represent the external IP of the deployed IoT Agent (the IP where the Context Broker will redirect the NGSI requests). E.g.: 'http://192.168.56.1:4041'.
- deviceRegistrationDuration: duration of the registrations as Context Providers and the subscriptions done by bidirectional plugin, in ISO 8601 standard format. E.g.: 'P1M'. Only used if agent is configured in NGSI v1 mode. In NGSI v2 mode the setting is ignored (registrations and subscriptions are non-expirable and the IOTA manages its removal explicitely).
- iotaVersion: indicates the version of the IoTA that will be displayed in the about method (it should be filled automatically by each IoTA).
- appendMode: if this flag is activated, the update requests to the Context Broker will be performed always with
APPEND type, instead of the default UPDATE. This have implications in the use of attributes with Context Providers,
so this flag should be used with care. This flag is overwritten by
autoprovisionflag in group or device provision. - dieOnUnexpectedError: if this flag is activated, the IoTAgent will not capture global exception, thus dying upon any unexpected error.
- singleConfigurationMode: enables the Single Configuration mode for backwards compatibility (see description in the Overview). Default to false.
- timestamp: if this flag is activated, the IoT Agent will add a 'TimeInstant' metadata attribute to all the
attributes updated from device information. This flag is overwritten by
timestampflag in group or device provision. - defaultResource: default string to use as resource for the registration of new Configurations (if no resource is provided).
- defaultKey: default string to use as API Key for devices that do not belong to a particular Configuration.
- componentName: default string identifying the component name for this IoT Agent in the logs.
- pollingExpiration: expiration time for commands waiting in the polling queue in miliseconds. If a command has been in the queue for this amount of time without being collected by the device, the expiration daemon will reclaim it. This attribute is optional (if it doesn't exist, commands won't expire).
- pollingDaemonFrequency: time between collection of expired commands in milliseconds. This attribute is optional (if this parameter doesn't exist the polling daemon won't be started).
- autocast: When enabled, the IoT Agents will try to cast attribute's values considering the JSON native type (only for NGSI v2).
- multiCore: When enabled, the IoT Agents runs in multi-thread environment to take advantage of multi-core
systems. It allows two values
trueorfalse. This attribute is optional with default to false, which means that the IoTAgent runs in a single thread. For more details about multi-core functionality, please refer to the Cluster module in Node.js and this section of the library documentation.
Some of the configuration parameters can be overriden with environment variables, to ease the use of those parameters with container-based technologies, like Docker, Heroku, etc...
The following table shows the accepted environment variables, as well as the configuration parameter the variable overrides.
| Environment variable | Configuration attribute |
|---|---|
| IOTA_CB_URL | contextBroker.url |
| IOTA_CB_HOST | contextBroker.host |
| IOTA_CB_PORT | contextBroker.port |
| IOTA_CB_NGSI_VERSION | contextBroker.ngsiVersion |
| IOTA_NORTH_HOST | server.host |
| IOTA_NORTH_PORT | server.port |
| IOTA_PROVIDER_URL | providerUrl |
| IOTA_AUTH_ENABLED | authentication.enabled |
| IOTA_AUTH_TYPE | authentication.type |
| IOTA_AUTH_HEADER | authentication.header |
| IOTA_AUTH_URL | authentication.url |
| IOTA_AUTH_HOST | authentication.host |
| IOTA_AUTH_PORT | authentication.port |
| IOTA_AUTH_USER | authentication.user |
| IOTA_AUTH_PASSWORD | authentication.password |
| IOTA_AUTH_CLIENT_ID | authentication.clientId |
| IOTA_AUTH_CLIENT_SECRET | authentication.clientSecret |
| IOTA_AUTH_TOKEN_PATH | authentication.tokenPath |
| IOTA_AUTH_PERMANENT_TOKEN | authentication.permanentToken |
| IOTA_REGISTRY_TYPE | deviceRegistry.type |
| IOTA_LOG_LEVEL | logLevel |
| IOTA_TIMESTAMP | timestamp |
| IOTA_IOTAM_URL | iotManager.url |
| IOTA_IOTAM_HOST | iotManager.host |
| IOTA_IOTAM_PORT | iotManager.port |
| IOTA_IOTAM_PATH | iotManager.path |
| IOTA_IOTAM_AGENTPATH | iotManager.agentPath |
| IOTA_IOTAM_PROTOCOL | iotManager.protocol |
| IOTA_IOTAM_DESCRIPTION | iotManager.description |
| IOTA_MONGO_HOST | mongodb.host |
| IOTA_MONGO_PORT | mongodb.port |
| IOTA_MONGO_DB | mongodb.db |
| IOTA_MONGO_REPLICASET | mongodb.replicaSet |
| IOTA_MONGO_RETRIES | mongodb.retries |
| IOTA_MONGO_RETRY_TIME | mongodb.retryTime |
| IOTA_SINGLE_MODE | singleConfigurationMode |
| IOTA_APPEND_MODE | appendMode |
| IOTA_POLLING_EXPIRATION | pollingExpiration |
| IOTA_POLLING_DAEMON_FREQ | pollingDaemonFrequency |
| IOTA_AUTOCAST | autocast |
| IOTA_MULTI_CORE | multiCore |
| IOTA_JSON_LD_CONTEXT | jsonLdContext |