Administration

The IoT Agent node library is not a standalone product and should be added as a dependency to package.json of the project is going to be used in. The library is published in the npm repository, so it can be added to the project by adding the following line to the package.json file:

...
"dependencies": {
    "iotagent-node-lib": "x.y.z",
}

wher x.y.z is an actual version number.

As alternative, you can use the master branch as dependency. In this case, you will be using the latest version of the code but note that some instability could exist (as the code in master is work in progress until the next version is closed).

...
"dependencies": {
    "iotagent-node-lib": "https://github.com/telefonicaid/iotagent-node-lib.git#master",
}

In order to use the library within your own IoT Agent, you must first you require it before use:

const iotagentLib = require('iotagent-node-lib');

Configuration

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 or from the environment variables. The configuration parameters work in the same way in both cases but the environment variables have precedence over the config.js file. The following sections describe the configuration parameters that can be used in the IoT Agent.

Configuration parameters:

These are the parameters that can be configured in the global section:

loglevel

It is the minimum log level to log. May take one of the following values: DEBUG, INFO, ERROR, FATAL. E.g.: 'DEBUG'.

contextBroker

It configures the connection parameters to stablish a connection 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' // or ['http://context1.json-ld','http://context2.json-ld'] if you need more than one
}

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 information.

  • If you want to support a "mixed" mode with both NGSI-v2 and NGSI-LD (experimental):
{
    host: '192.168.56.101',
    port: '1026',
    ngsiVersion: 'mixed',
    jsonLdContext: 'http://context.json-ld' // or ['http://context1.json-ld','http://context2.json-ld'] if you need more than one
}

Under mixed mode, NGSI v2 payloads are used for context broker communications by default, but this payload may also be switched to NGSI LD at service group or device provisioning time using the ngsiVersion field in the provisioning API. The ngsiVersion field switch may be added at either group or device level, with the device level overriding the group setting.

server

This parameter is 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 port attribute is required. If no baseRoot attribute is used, '/' is used by default. E.g.:

{
    baseRoot: '/',
    port: 4041
}

When connected to an NGSI-LD context broker, an IoT Agent is able to indicate whether it is willing to accept null values and also whether it is able to process the NGSI-LD datasetId metadata element. Setting these values to false will cause the IoT Agent to return a 400 Bad Request HTTP status code explaining that the IoT Agent does not support nulls or multi-attribute requests if they are encountered.

{
    baseRoot: '/',
    port: 4041,
    ldSupport : {
      null: true,
      datasetId: true
    }
}

stats

It configures the periodic collection of statistics. Use interval in milliseconds to set the time between stats writings.

stats: {
    interval: 100;
}

authentication

Stores the 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: keystone and oauth2. Authentication need to be enabled by setting the field enabled to true. In keystone based authentication, the trust associated to the device or deviceGroup is a token representing a specific user and his rights on a given domain (i.e. combination of fiware-service and fiware-servicepath). The authentication process use the trust delegation workflow to check if the trust provided is valid, in which case return a x-subject-token that can be used to authenticate the request to the Context Broker. Required parameters are: the url of the keystone to be used (alternatively host and port but if you use this combination, the IoT Agent will assume that the protocol is HTTP), the user and password to which it is delegated the trust verification. 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

Stores type of Device Registry to create. Currently, two values are supported: memory and mongodb. 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 the mongob section (as described bellow). E.g.:

{
    type: 'mongodb';
}

mongodb

It configures the MongoDB driver for those repositories with 'mongodb' type. If the host parameter is a list of comma-separated IPs, they will be considered to be part of a Replica Set. In that case, the optional property replicaSet should contain the Replica Set name. If the database requires authentication, username (user), password (password) and authSource (authSource) can be set. If the database requires TLS/SSL connection but any validation of the certificate chain is not mandatory, all you need is to set the ssl (ssl) option as true to connect the database. If you need to add more complex option(s) such as retryWrites=true or w=majority when connection database, extraArgs (extraArgs) can be used to perform it. For The MongoBD driver will retry the connection at startup time retries times, waiting retryTime seconds 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
}

{
  host: 'mongodb-0,mongodb-1,mongodb-2',
  port: '27017',
  db: 'iotagent',
  replicaSet: 'rs0',
  user: 'rootuser',
  password: 'password',
  authSource: 'admin',
  ssl: true,
  extraArgs: {
    retryWrites: true,
    readPreference: 'nearest',
    w: 'majority'
  },
  retries: 5,
  retryTime: 5
}

iotManager

This parameter 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, port and path indicated, with the information configured in the object. The IoTAgent URL that will be reported will be the providedUrl (described below) with the added agentPath:

{
    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.

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'.

iotaVersion

indicates the version of the IoTA that will be displayed in the about method (it should be filled automatically by each IoTA).

dieOnUnexpectedError

if this flag is activated, the IoTAgent will not capture global exception, thus dying upon any unexpected error.

timestamp

if this flag is activated:

  • For NGSI-v2, the IoT Agent will add a TimeInstant metadata attribute to all the attributes updated from device information. This flag is overwritten by timestamp flag in group or device
  • With NGSI-LD, the standard observedAt property-of-a-property is created instead.

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).

multiCore

When enabled, the IoT Agents runs in multi-thread environment to take advantage of multi-core systems. It allows two values true or false. 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.

fallbackTenant

For Linked Data Context Brokers which do not support multi-tenancy, this provides an alternative mechanism for supplying the NGSILD-Tenant header. Note that NGSILD-Tenant has not yet been included in the NGSI-LD standard (it has been proposed for the next update of the standard, but the final decision has yet been confirmed), take into account it could change. Note that for backwards compatibility with NGSI v2, the fiware-service header is already used as alternative if the NGSILD-Tenant header is not supplied.

fallbackPath

For Linked Data Context Brokers which do not support a service path, this provides an alternative mechanism for suppling the NGSILD-Path header. Note that for backwards compatibility with NGSI v2, the fiware-servicepath header is already used as alternative if the NGSILD-Path header is not supplied. Note that NGSILD-Path has not yet been included in the NGSI-LD standard (it has been proposed for the next update of the standard, but the final decision has yet been confirmed), take into account it could change

explicitAttrs

if this flag is activated, only provisioned attributes will be processed to Context Broker. This flag is overwritten by explicitAttrs flag in group or device provision. Additionally explicitAttrs can be used to define which meassures defined in JSON/JEXL array will be propagated to NGSI interface.

defaultEntityNameConjunction

the default conjunction string used to compose a default entity_name when is not provided at device provisioning time; in that case entity_name is composed by type + : + device_id. Default value is :. This value is overwritten by defaultEntityNameConjunction in group provision.

relaxTemplateValidation

if this flag is activated, objectId attributes for incoming devices are not validated, and may exceptionally include characters (such as semi-colons) which are forbidden according to the NGSI specification. When provisioning devices, it is necessary that the developer provides valid objectId-name mappings whenever relaxed mode is used, to prevent the consumption of forbidden characters.

Configuration using environment variables

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_LD_SUPPORT_NULL server.ldSupport.null
IOTA_LD_SUPPORT_DATASET_ID server.ldSupport.datasetId
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_USER mongodb.user
IOTA_MONGO_PASSWORD mongodb.password
IOTA_MONGO_AUTH_SOURCE mongodb.authSource
IOTA_MONGO_RETRIES mongodb.retries
IOTA_MONGO_RETRY_TIME mongodb.retryTime
IOTA_MONGO_SSL mongodb.ssl
IOTA_MONGO_EXTRAARGS mongodb.extraArgs
IOTA_POLLING_EXPIRATION pollingExpiration
IOTA_POLLING_DAEMON_FREQ pollingDaemonFrequency
IOTA_MULTI_CORE multiCore
IOTA_JSON_LD_CONTEXT jsonLdContext
IOTA_FALLBACK_TENANT fallbackTenant
IOTA_FALLBACK_PATH fallbackPath
IOTA_EXPLICIT_ATTRS explicitAttrs
IOTA_DEFAULT_ENTITY_NAME_CONJUNCTION defaultEntityNameConjunction
IOTA_RELAX_TEMPLATE_VALIDATION relaxTemplateValidation

Note:

  • If you need to pass more than one JSON-LD context, you can define the IOTA_JSON_LD_CONTEXT environment variable as a comma separated list of contexts (e.g. 'http://context1.json-ld,http://context2.json-ld')

Logs

This section describes the logs that can be generated by the IoT Agent library. The IoT Agent library uses the following log levels:

Level Description
DEBUG Used to log information useful for debugging.
INFO Used to log information about the normal operation of the IoT Agent library.
ERROR Used to log information about errors that may affect the IoT Agent library.
FATAL Used to log information about fatal errors that may affect the IoT Agent library.

Additionally, every error log has an associated error code that can be used to identify the error. The error codes are composed by a prefix and a number. The following table shows the prefixes used in the IoT Agent library:

Prefix Type of operation
MONGODB Errors related with the MongoDB repository
IOTAM Errors related with the IoTA Manager
KEYSTONE Errors related with trust token retrieval
ORION Errors in Context Broker access
VALIDATION-FATAL Errors related with management of the Validation templates

Errors

Error code Error name Description
GENERAL-001 Couldn't find callback in listDevices call. Implies that the callback function was not found in the listDevices call. This error is thrown when the callback function is not provided in the listDevices call.
MONGODB-001 Error trying to connect to MongoDB: %s Implies there has been an error connecting with the DB. The component will automatically retry from this error, but it may be a sign of connectivity problems between the DB and the component. If the connection cannot be restablished from this error, a MONGODB-002 error will be raised.
MONGODB-002 Error found after [%d] attempts: %s Indicates that it was impossible to establish a connection to the MongoDB cluster, even after retrying N times. This could be caused by a connectivity problem with the MongoDB machine, a problem in the MongoDB cluster, or a misconfiguration of the IoTA Manager. Check the conectivity, the state of the MongoDB cluster and the Mongo configuration data.
MONGODB-003 No host found for MongoDB driver. This error will thrown if MongoDB is selected as the configured repository for data but some information is missing in the configuration file. Check the configuration file and add all the required information.
MONGODB-004 MongoDB connection was lost. Indicates that it was impossible to reestablish the connection with the MongoDB server after retrying N times. This could be caused by a connectivity problem with the MongoDB machine or by changes on the configuration of the MongoDB server done while the IoT Agent was running. This error is only thrown when using a single MongoDB instance or when using sharding but just a single mongos proxy. When using MongoDB instances using replica sets or multiple mongos servers, the IoT Agent will retry connecting forever alternating between the different nodes.
IOTAM-001 Error updating information in the IOTAM. Status Code [%d] The IoT Agent could not contact the IoT Agent manager to update its information. This condition may indicate a lack of connectivity between machines or a problem in the IoT Agent Manager. The IoT Agent information in the IoT Agent Manager will be out-of-date until this problem is solved.
KEYSTONE-001 Error retrieving token from Keystone: %s There was connection error connecting with Keystone to retrieve a token. This condition may indicate a lack of connectivity between both machines or a problem with Keystone.
KEYSTONE-002 Unexpected status code: %d There was a problem retrieving a token from keystone that was not caused by connectivity errors. Check the Keystone log for errors and the security configuration in the IoTAgent. This may also be caused by a wrong trust token used by the user.
KEYSTONE-003 Token missing in the response headers. Authentication flow worked correctly, but the response headers did not include the expected header x-subject-token. Check the Keystone logs and configuration.
OAUTH2-001 Error retrieving token from OAuth2 provider: %s There was connection error connecting with OAuth2 provider to retrieve a token. This condition may indicate a lack of connectivity between both machines or a problem with OAuth2 provider.
OAUTH2-002 Unexpected status code: %d There was a problem retrieving a token from OAuth2 provider that was not caused by connectivity errors. Check the OAuth2 provider log for errors and the security configuration in the IoTAgent. This may also be caused by an invalid refresh_token used by the user.
OAUTH2-003 Token missing in the response body The JSON response body returned by the OAuth2 provider does not include a field access_token. Check the OAuth2 logs and configuration.
ORION-001 Connection error creating initial entity in the Context Broker: %s There was a connectivity error accessing Context Broker to create an initial entity (or the Context Broker was down). Check connectivity between the machines, the status of the remote Context Broker and the configuration of the IoTAgent.
ORION-002 Connection error sending registrations to the Context Broker: %s There was a connectivity error accessing Context Broker to register the IoTA as a Context Provider (or the Context Broker was down). Check connectivity between the machines, the status of the remote Context Broker and the configuration of the IoT Agent.
VALIDATION-FATAL-001 Validation Request templates not found Validation templates were not found. Check all the validation templates are properly located in the IoTAgent Library folder and that the file permissions are correct.

Alarms

The following table shows the alarms that can be raised in the IoTAgent library. All the alarms are signaled by a error log starting with the prefix "Raising [%s]:" (where %s is the alarm name). All the alarms are released by an info log with the prefix "Releasing [%s]". These texts appear in the msg= field of the generic log record format.

Alarm name Severity Description
MONGO-ALARM_XX Critical Indicates an error in the MongoDB connectivity
ORION-ALARM Critical Indicates a persistent error accesing the Context Broker
IOTAM-ALARM Critical Indicates a persistent error accessing the IoTAM

while the 'Severity' criterium is as follows:

  • Critical - The system is not working
  • Major - The system has a problem that degrades the service and must be addressed
  • Warning - It is happening something that must be notified

In order to identify the internal flow which origins a mongo alarm, there is a suffix _XX which identifies from 01 to 11 each flow.