Exposure Notifications Express (EN Express) Configuration

Overview

EN Express apps can be configured by providing a JSON configuration file with the following format.

{
  "config": {
    FIELDS BELOW...
  }
}

Each name.json config file placed in the app/config/ directory will add a Gradle build flavor, introducing additional tasks:

assembleName - build an APK for this config.
bundleName - build an AAB for this config.
publishListingName - push a listing to the Play Store.
publishAppName - push an app bundle to the Play Store.
publishConsentName - create a consent.json with consent fields.

Android Specific Fields

Due to platform differences, there are several fields only relevant to Android. Most will be available in Apple Business Registry (ABR), except where noted.

Play Store Related

These fields influence how the EN Express app will appear in Play Store.

playStoreAppTitle

ABR Field: (tentative: Play Store app title)
Data Type: String
Limit: 50 chars
Localizable

Your app's name on Google Play. Recommended 30 or less.

Optional field, defaults to appTitle if blank.

playStoreShortDescription

ABR Field: (tentative: Play Store short description)
Data Type: String
Limit: 80 chars
Localizable

Short description of the app for the Play Store. The first text users see when looking at your app's detail page on the Play Store app.

Users can expand this text to view your app's full description.

Optional field, defaults to agencyDisplayName if blank.

playStoreFullDescription

ABR Field: (tentative: Play Store full description)
Data Type: String
Limit: 4000 chars
Localizable

Your app's description on Google Play. Users can expand this text to view your app's full description.

Optional field, defaults to agencyDisplayName if blank.

playStoreAppIcon

ABR Field: (tenatative: Play Store icon)
Data Type: URL

URL for the Play Store Hi-Res Icon.

Must in PNG format. 512 x 512 pixel

Used for store listing.

Optional field, defaults to app icon if blank.

agencyPrivacyPolicy

ABR Field: (tentative: Privacy Policy)
Data Type: URL

Link to your app's Privacy Policy.

The privacy policy must, together with any in-app disclosures, comprehensively disclose how your app collects, uses, and shares user data, including the types of parties with whom it’s shared. You should consult your own legal representative to advise you of what is required.

playStoreEmailContact

ABR Field: (tentative: Admin contact for Play Store)
Data Type: String

Administrative contact for Play Store. This contact email address will be publicly displayed as part of the Play Store listing.

playStoreDefaultLocale

ABR Field: (tentative: Default locale for Play Store)
Data Type: String

Default locale for Play Store listing.

Optional, if absent, will auto-select based on provided locales.

Android App Specific

appTitle

ABR Field: Title for the PHA app.
Data Type: String
Limit: 50 chars Localizable

Title for the PHA app. Recommended 30 or less. As the app title may be clipped when long, 12 characters or less for visibility.

Optional field, defaults to agencyDisplayName if blank

appLinkHost

ABR Field: (unknown)
Data Type: String\

Hostname to use to create an App Link association for SMS redirection.

Required Field

agencyIconForeground

ABR Field: URL for foreground portion of icon.
Data Type: URL

URL for the foreground portion of an Android Adaptive Icon.

Must be in either SVG or PNG. SVG Recommended.

Should be sized to be laid out at 108dp x 108dp with the center 72dp x 72dp region visible with either a square, round, or other adaptive stencils. May require padding with a transparent reference square.

Optional field, defaults to automatic layout of agencyImage if blank.

agencyIconBackground

ABR Field: URL for background portion of icon.
Data Type: URL

URL for the background portion of an Android Adaptive Icon.

Must be in either SVG or PNG. SVG Recommended.

Should be sized to be laid out at 108dp x 108dp with the center 72dp x 72dp region visible with either a square, round, or other adaptive stencils. May require padding with a transparent reference square.

Optional field, defaults to solid agencyColor background if blank.

tekRoamingURLs

ABR Field: (unavailable)
Data Type: URL

Mapping from ISO-3166-1 to an additional list of base and index URLs for download when the user has roamed to that country. Includes base and index URLs. Indexes are de-duped before download.

Typically provided by your roaming federation.

Example:

{
  "US": [
   {"index": "https://my-key-server/exposureKeyExport-US/index.txt"
                     "base": "https://my-key-serrver/exposureKeyExport-US"},
   {"index": "https://my-key-server/exposureKeyExport-TRAVEL/index.txt"
                     "base": "https://my-key-server/exposureKeyExport-TRAVEL"},
           ],
  "DE": [
   {"index": "https://my-key-server/exposureKeyExport-DE/index.txt"
                     "base": "https://my-key-server/exposureKeyExport-DE"},
   {"index": "https://my-key-server/exposureKeyExport-TRAVEL/index.txt"
                     "base": "https://my-key-server/exposureKeyExport-TRAVEL"},
        ],
}

Optional field, defaults to no roaming if blank.

ENPA Specific Fields

Exposure Notifications Private Analytics (ENPA) has some additional configuration fields.

enableENPA

ABR Field: (unknown)
Data Type: Boolean\

This field is true to enable ENPA.

enpaConsentText

ABR Field: ENPA Consent Text
Data Type: String
Required
Localizable

A string that contains the plain text end-user consent document provided by the PHA for ENPA.

enpaConsentVersion

ABR Field: ENPA Consent Version
Data Type: String
Limit: 25 chars
Required
Localizable

A string that contains the semantic version or monotonically increasing number of the consent text for ENPA.

General Fields

These fields are relevant both to Android and iOS.

Health Authority Identification

healthAuthorityID

ABR Field: (tenatative)
Data Type: String
Limit: 256 chars
Required

String used to identify the PHA to the upload key server.

On Android, this also sets the app package name. Once set, it cannot be changed.

agencyDisplayName

ABR Field: PHA Name
Data Type: String
Limit: 50 chars
Required
Localizable

Name of the PHA. Used in the colored header during onboarding, in EN settings and in Exposure Notifications details.

agencyRegionName

ABR Field: Region
Data Type: String
Limit: 50 chars
Required
Localizable

Name of the region the PHA manages. Used as the subtitle in the onboarding header and in various places in Settings. PHA must provide this field.

agencyWebsiteURL

ABR Field: Agency Website URL
Data Type: URL
Limit: 500 chars

The URL for the agency's website. Presented to the user in the region’s detail view in Settings.

agencyHeaderStyle

ABR Field: Header Style
Data Type: UInt8
Default: 0

An integer used to customize the appearance of the header used in Exposure Notifications Express when presenting region-specific information to the user. Acceptable values are: 0 for standard appearance with name and icon, 1 for icon-only centered, 2 for icon-only on the left, and 3 for icon-only on the right.

agencyHeaderTextColor

ABR Field: Text Color
Data Type: [Float]
Default: [1.0, 1.0, 1.0]

An array of RGB values ranging from 0.0 to 1.0 representing the text color for the text in the header (for example, [1.0, 0.75, 0.75]).

agencyColor

ABR Field: Header Color
Data Type: [Float]
Default: [0.0, 0.0, 0.0]

An array of RGB values ranging from 0.0 to 1.0 representing the accent color to use as the background for the PHA-branded header above PHA-provided content (for example, [1.0, 1.0, 0.0]).

agencyImage

ABR Field: Image URL
Data Type: URL/String

The URL of an image file for the agency logo, displayed in the PHA-branded header above PHA-provided content.

agencyMessage

ABR Field: Message Body
Data Type: String
Limit: 3000 chars
Required
Localizable

Summary text that appears during onboarding and in settings below the branded header.

regionIdentifier

ABR Field: MCC Code in v1, ISO Country Code in v2
Data Type: String
Default: N/A

Either the ISO-3166-1 two letter country code, or the ISO-3166-1 alpha-2 country + state code.

Example:

US-CA (United States, California)
DE (Germany)

MCC Code in v1, Apple only

Legal Consent

legalConsentText

ABR Field: Legal Consent Text
Data Type: String
Required
Localizable

A string that contains the plain text end-user consent document provided by the PHA.

legalConsentVersion

ABR Field: Legal Consent Version
Data Type: String
Limit: 25 chars
Required
Localizable

A string that contains the semantic version or monotonically increasing number of the consent text.

Risk Score -- Overview

The risk score for a given exposure is computed using:

ERV = (Attenuation Weight) x (Infectiousness Weight) x (Report Type Weight)

It combines the seconds below.

Risk Score -- Attenuation Weight

attenuationImmediateWeight

ABR Field: Attenuation Immediate Weight (0-250%)
Data Type: Uint16
Range: 0 - 250
Default: 150

IMMEDIATE attenuation bucket weight.

attenuationNearWeight

ABR Field: Attenuation Near Weight (0-250%)
Data Type: Uint16
Range: 0 - 250
Default: 100

NEAR attenuation bucket weight.

attenuationMedWeight

ABR Field: Attenuation Medium Weight (0-250%)
Data Type: Uint16
Range: 0 - 250
Default: 50

MEDIUM attenuation bucket weight.

attenuationOtherWeight

ABR Field: Attenuation Other Weight (0-250%)
Data Type: Uint16
Range: 0 - 250
Default: 0

OTHER attenuation bucket weight.

attenuationImmediateNearThreshold

ABR Field: Attenuation Immediate Near Threshold (0-255)
Data Type: Uint8
Range: 0 - 255
Default: 30

IMMEDIATE-NEAR attenuation threshold.

attenuationNearMedThreshold

ABR Field: Attenuation Immediate Med Threshold (0-255)
Data Type: Uint8
Range: 0 - 255
Default: 50

NEAR-MEDIUM attenuation threshold.

attenuationMedFarThreshold

ABR Field: Attenuation Med Far Threshold (0-255)
Data Type: Uint8
Range: 0 - 255
Default: 60

MEDIUM-FAR (OTHER) attenuation threshold.

Risk Score -- Infectiousness Weight

symptomOnsetToInfectiousnessMap

ABR Field: Infectiousness to Symptom Onset Map
Data Type: Uint64
Range: 0 - 0xFFFFFFFF
Default: 0x0401555AA9400000

Map from days-since-symptoms-onset in TEK to infectiousness bucket.

Three possible values per entry (in binary):

00 - Drop
01 - Standard infectiousness (infectiousnessStandardWeight)
10 - High infectiousness (infectiousnessHighWeight)

Stored Least Significant Bit first: -14,-13 …. 13, 14 / None.

NOTE: Currently this is stored inside a string to ensure Uint64 size.

infectiousnessStandardWeight

ABR Field: Infectiousness Standard Weight (0-250%)
Data Type: Uint16
Range: 0 - 250
Default: 100

Weight value for onset dates deemed normal risk.

infectiousnessHighWeight

ABR Field: Infectiousness High Weight (0-250%)
Data Type: Uint16
Range: 0 - 250
Default: 100

Weight value for onset dates deemed high risk.

Risk Score -- Report Type Weight

reportTypeConfirmedTestWeight

ABR Field: Report Type Confirmed Test Weight (0-250%)
Data Type: Uint16
Range: 0 - 250
Default: 100

Weight to apply to report type CONFIRMED_TEST.

Risk Score -- Report Type Weights

reportTypeConfirmedClinicalDiagnosisWeight

ABR Field: Report Type Confirmed Clinical Diagnosis Weight (0-250%)
Data Type: Uint16
Range: 0 - 250
Default: 100

Weight to apply to report type CLINICAL_DIAGNOSIS.

reportTypeSelfReportWeight

ABR Field: Report Type Self Report Weight (0-250%)
Data Type: Uint16
Range: 0 - 250
Default: 100

Weight to apply to report type SELF_REPORT.

reportTypeNoneMap

ABR Field: Report Type None Map
Data Type: Uint8
Range: 0 - 3
Default: 3

This value selects what to map report types to that don't have a report type attached:

0 = DROP
1 = CONFIRMED_TEST
2 = CLINICAL_DIAGNOSIS
3 = SELF_REPORT

Risk Score -- General Thresholds

daysSinceExposureThreshold

ABR Field: Days Since Exposure Threshold (0-14)
Data Type: Uint8
Range: 0 - 14
Default: 14

Limit of how many days of exposure will be considered when evaluating the user’s total exposure.

For example, 10 means only the past 10 days of history is considered.

Exposure Classifications

These keys define values that set the thresholds and messaging for up to 4 exposure classifications (numbered 1-4). Classifications with the lowest number have the highest priority, if multiple classifications apply to a user.

Replace the trailing X in the key name with 1-4 for each classification.

classificationName_X

ABR Field: Classification Name
Data Type: String
Limit: 25 chars

Unique name of this classification configuration. This name must change when the thresholds for this classification change.

exposureDetailsBodyText_X

ABR Field: Exposure Details Body
Data Type: String
Limit: 1500 chars
Localizable

Body text presented to user when navigating to their latest exposure details in Settings.

notificationSubject_X

ABR Field: Notification Subject
Data Type: String
Limit: 50 chars
Localizable

Bolded subject of the notification presented to user when transitioning to this exposure state. Also presented as the heading in Settings when a user browses to their latest exposure information. This field is required.

notificationBody_X

ABR Field: Notification Body
Data Type: String
Limit: 256 chars
Localizable

Body text of notification presented to user when transitioning to this exposure state.

classificationURL_X

ABR Field: Classification URL
Data Type: URL
Limit: 500 chars

URL used to link to PHA website for further guidance when user navigates to their latest exposure details in Settings.

confirmedTestPerDaySumERVThreshold_X

ABR Field: Recursive Per Day Sum ERV Threshold
Data Type: Uint32
Range: 0 - 0xFFFFFFFF
Default: 0

Confirmed test report type threshold in ERV of when an OS notification is raised.