IO mobile backend

This repository contains the code of the backend used by the mobile applications of the IO project.

Table of content

• IO mobile backend
  • Table of content
  • What is this?
  • Authentication process
    • Token authentication
  • How to run the application
    • Dependencies
    • Installation steps
    • Container description
    • Environment variables
    • Logs
  • API Monitoring
  • Redis Database
    • Data Structure
  • Mobile App compatibility
    • Backend
    • PagoPa
  • How to contribute
    • Dependencies
    • Starting steps
    • Architecture decision records
  • Troubleshooting

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What is this?

This is the backend that supports the io-app mobile application.

This project is part of the Italian Digital Citizenship initiative, see the main repository for further information.

Authentication process

The io-app application will authenticate using the APIs exposed by the service Session Manager in IO Auth monorepo.

Once the token is obtained it can be used to call authenticated APIs of this repository.

Token authentication

All API requests sent by the client to the backend must have an Authorization: Bearer header with the value of the token obtained from the SPID authentication process. The token is used to retrieve the User object from the SessionStorage service.

The code that manage this flow are in the src/strategies/bearerSessionTokenStrategy.ts file.

How to run the application

Dependencies

• Docker and Docker Compose

A Linux/macOS environment is required at the moment.

Installation steps

1. clone the project in a folder called io-backend

2. go to the project's folder

3. run scripts/build-tools.sh to build the tools Docker image

4. run scripts/yarn.sh to install backend dependencies

5. run scripts/generate-proxy-api-models.sh to generate the models defined in api_proxy.yaml and api_notifications.yaml

6. run scripts/build.sh to compile the Typescript files

7. run scripts/generate-test-certs.sh to create certificates needed to start the HTTPS server in DEV mode

8. edit your /etc/hosts file by adding:

   127.0.0.1    io-backend
   

9. copy .env.example to .env and fill the variables with your values

10. run docker compose --env-file .env up -d to start the containers

11. point your browser to https://io-backend/info to check that the server is started

If you are using Docker with a Docker Machine replace localhost with the IP of the Docker Machine (More details here).

Container description

• backend: the backend Node application that serves the web and mobile applications

Nginx is reachable at https://io-backend \

Environment variables

Those are all Environment variables needed by the application:

Variable name	Description	type
API_KEY	The key used to authenticate to the io-functions-app API	string
API_URL	The io-functions-app URL	string
API_BASE_PATH	The root path for the backend api endpoints	string
BONUS_API_KEY	The key used to authenticate to the io-functions-bonus API	string
BONUS_API_URL	The io-functions-bonus URL	string
BONUS_API_BASE_PATH	The root path for the backend bonus api endpoints	string
CGN_API_KEY	The key used to authenticate to the io-functions-cgn API	string
CGN_API_URL	The io-functions-cgn URL	string
CGN_API_BASE_PATH	The root path for the backend cgn api endpoints	string
PORT	The HTTP port the Express server is listening to	int
REDIS_URL	The URL of a Redis instance	string
PRE_SHARED_KEY	The key shared with the API backend to authenticate the webhook notifications	string
ALLOW_NOTIFY_IP_SOURCE_RANGE	The range in CIDR form of allowed IPs for the webhook notifications	string
NOTIFICATIONS_STORAGE_CONNECTION_STRING	Connection string to Azure queue storage for notification hub messages	string
NOTIFICATIONS_QUEUE_NAME	Queue name of Azure queue storage for notification hub messages	string
ALLOW_MYPORTAL_IP_SOURCE_RANGE	The range in CIDR form of allowed IPs for the MyPortal API	string
ALLOW_SESSION_HANDLER_IP_SOURCE_RANGE	The range in CIDR form of IPs of service allowed to handle user sessions	string
AUTHENTICATION_BASE_PATH	The root path for the authentication endpoints	string
PAGOPA_API_URL_PROD	The url for the PagoPA api endpoints in prod mode	string
PAGOPA_API_KEY_PROD	The api-key needed to call the pagopa proxy API	string
PAGOPA_API_URL_TEST	The url for the PagoPA api endpoints in test mode	string
PAGOPA_API_KEY_UAT	The api-key needed to call the pagopa proxy API for UAT instance	string
MYPORTAL_BASE_PATH	The root path for the MyPortal endpoints	string
CACHE_MAX_AGE_SECONDS	The value in seconds for duration of in-memory api cache	int
APICACHE_DEBUG	When is true enable the apicache debug mode	boolean
GITHUB_TOKEN	The value of your Github Api Key, used in build phase	string
FETCH_KEEPALIVE_ENABLED	When is true enables keepalive agent in the API client (defaults to false)	boolean
FETCH_KEEPALIVE_MAX_SOCKETS	(Optional) See agentkeepalive
FETCH_KEEPALIVE_FREE_SOCKET_TIMEOUT_MS	(Optional) See agentkeepalive
FETCH_KEEPALIVE_KEEPALIVE_MSECS	(Optional) See agentkeepalive
FETCH_KEEPALIVE_MAX_FREE_SOCKETS	(Optional) See agentkeepalive
FETCH_KEEPALIVE_TIMEOUT	(Optional) See agentkeepalive
FETCH_KEEPALIVE_SOCKET_ACTIVE_TTL	(Optional) See agentkeepalive
FF_CGN_ENABLED	When is true (namely 1) enables CGN API to be registered into backend app	boolean
FF_CGN_ENABLED	When is true (namely 1) enables CGN API to be registered into backend app	boolean
APP_MESSAGES_API_KEY	The key used to authenticate to the io-functions-app-messages API	string
APP_MESSAGES_API_URL	The io-functions-app-messages URL	string
THIRD_PARTY_CONFIG_LIST	(Optional, default empty) A list of ThirdParty Configuration	stringified JSON
IS_APPBACKENDLI	(Optional, default false) Enables notify and session lock endpoints working only on appbackendli	boolean
FF_PN_ACTIVATION_ENABLED	(Optional) Enable the integration with PN for Service Activation (1 enabled)	int
PN_ACTIVATION_BASE_PATH	(Required if FF_PN_ACTIVATION_ENABLED = 1) base path for activation endpoint	string
PN_API_KEY	(Required if FF_PN_ACTIVATION_ENABLED = 1) PN API key for production environment	string
PN_API_KEY_UAT	(Required if FF_PN_ACTIVATION_ENABLED = 1) PN API key for UAT environment	string
PN_API_URL	(Required if FF_PN_ACTIVATION_ENABLED = 1) PN API base url for production	string
PN_API_URL_UAT	(Required if FF_PN_ACTIVATION_ENABLED = 1) PN API base url for UAT environment	string
FF_IO_SIGN_ENABLED	When is true (namely 1) enables IO SIGN API to be registered into backend app	boolean
IO_SIGN_API_BASE_PATH	The root path for the backend io-sign api endpoints	string
IO_SIGN_API_KEY	The key used to authenticate to the io-func-sign-user API	string
IO_SIGN_API_URL	The io-func-sign-user URL	string
LOLLIPOP_API_KEY	The key used to authenticate to the io-function-lollipop API	string
LOLLIPOP_API_URL	The io-function-lollipop URL	string
LOLLIPOP_API_BASE_PATH	The io-function-lollipop api base path	string
LOLLIPOP_REVOKE_STORAGE_CONNECTION_STRING	Connection string to Azure queue storage for revoke Users lollipop PubKeys	string
LOLLIPOP_REVOKE_QUEUE_NAME	Queue name of Azure queue storage for revoke Users lollipop PubKeys	string
LOCKED_PROFILES_STORAGE_CONNECTION_STRING	Connection string to Azure queue storage for locked profiles table	string
LOCKED_PROFILES_TABLE_NAME	The locked profiles table name	string
FF_UNIQUE_EMAIL_ENFORCEMENT	(Optional) Enable the unique email enforcement policy. Default: NONE	string (enum: NONE, BETA, ALL)
UNIQUE_EMAIL_ENFORCEMENT_USERS	(Optional) Comma separated list of UNIQUE_EMAIL_ENFORCEMENT beta testers. Default: empty array	string
SERVICES_APP_BACKEND_BASE_PATH	New Service APIs(include search engine) basepath	string
SERVICES_APP_BACKEND_API_URL	Services App Backend FunctionApp Url	string
SERVICES_APP_BACKEND_API_BASE_PATH	Services App Backend FunctionApp Api Basepath	string
FF_TRIAL_SYSTEM_ENABLED	(Optional) enables Trial System API to be registered into backend app - default false	string
TRIAL_SYSTEM_API_BASE_PATH	Trial System Api Base path	string
TRIAL_SYSTEM_API_URL	Trial System FunctionApp Api url	string
TRIAL_SYSTEM_API_KEY	The key used to authenticate to the Trial System API	string

Notes:

• FETCH_KEEPALIVE_ENABLED should be enabled when deploying on Azure App Service to avoid SNAT Exhaustion
• FETCH_KEEPALIVE_MAX_SOCKETS depends on the number of node processes running on the VM, see this article and this issue
• FETCH_KEEPALIVE_SOCKET_ACTIVE_TTL should be set at around 100 seconds when deploying on Azure, see this comment

If you are trying to run the docker images on your local environment (through the docker-compose) you must set the following variables:

• NOTIFICATIONS_STORAGE_CONNECTION_STRING
• PUSH_NOTIFICATIONS_STORAGE_CONNECTION_STRING
• LOLLIPOP_REVOKE_STORAGE_CONNECTION_STRING With this connection string as value:
• DefaultEndpointsProtocol=http;AccountName=devstoreaccount1;AccountKey=Eby8vdM02xNOcqFlqUwJPLlmEtlCDXJ1OUzFT50uSRZ6IFsuFq2UVErCz4I6tq/K1SZFPTOtr/KBHBeksoGMGw==;BlobEndpoint=http://127.0.0.1:20003/devstoreaccount1;QueueEndpoint=http://127.0.0.1:20004/devstoreaccount1;TableEndpoint=http://127.0.0.1:20005/devstoreaccount1;

The connection string has a default value needed to connect to Azurite, a local emulator used to provide a free local environment for testing an Azure Blob, Queue Storage, and Table Storage application. As for docker-compose instructions, the Azurite docker image runs the Blob service on port 20003, the Queue service on port 20004 and the Table service on port 20005. If Azurite is executed on different address or ports, the connection string must be changed according to the service.

You must also set the following variables:

• REDIS_URL
• REDIS_PORT
• REDIS_PASSWORD

With the same values defined in the docker-compose.yml file.

Logs

Application logs are saved into the logs folder.

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API Monitoring

Is possible link the API to AppInsignts service by setting the ENV variable APPINSIGHTS_INSTRUMENTATIONKEY. Stats of API CPU and RAM usage, API call execution time, success or failure of API calls are collected. Realtime data collection is enabled.

Redis Database

Data Structure

Redis Database stores data required only by application side functionalities. Below a table with an example of data for an hypothetical user with fiscal code MRARSS80A01H501T and with session token HexToken.

Key	Value	type	expire in
SESSION-HexToken	a JSON representing the user object	User	TOKEN_DURATION_IN_SECONDS
WALLET-WalletHexToken	"SESSION-HexToken"	String	TOKEN_DURATION_IN_SECONDS
SESSIONINFO-HexToken	a JSON representing the SessionInfo object	SessionInfo	TOKEN_DURATION_IN_SECONDS
USERSESSIONS-MRARSS80A01H501T	a Set of SessionInfo Keys	Set<SessionInfoKey>	never

Mobile App compatibility

Backend

To handle Backend compatibility with several Mobile App versions, the oldest mobile app version supported by the backend is stored into the property min_app_version inside the package.json. This value is provided to the app through the /info API. If the mobile app version is lower an upgrade is required.

PagoPa

To handle the mobile app compatibility with the latest implementation of PagoPA APIs, the backend exposes through the /info API a property called min_app_version_pagopa defined into package.json file. If the mobile app version is lower of this value, all the functions that require PagoPa are disabled to avoid compatibility issues.

How to contribute

Dependencies

• nodenv
• YARN
• Docker (optional)

A Linux/macOS environment is required at the moment.

Starting steps

• use nodenv to run the correct version of Nodejs as specified in app/.node-version
• run Jest tests directly or with scripts/test.sh

In general follow the Node Best Practices.

Architecture decision records

In a world of evolutionary architecture, it's important to record certain design decisions for the benefit of future team members as well as for external oversight. Architecture Decision Records is a technique for capturing important architectural decisions along with their context and consequences. We store these details in source control, along with code, as then they can provide a record that remains in sync with the code itself.

We use ADRs to track architectural decisions of this initiative.

This repository is configured for Nat Pryce's adr-tools.

Here's the decisions we taken so far:

ADR	Title	PR (discussion)
1	Record architecture decisions
2	Backend runs on Docker on local environments
3	Use OpenAPI to defined the API specs
4	Use a dependency injection container
5	Use a GUID as Installation ID
6	Backend is deployed on more than one instance

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Troubleshooting

I installed on my mac but seems that https://io-backend is not working (ping io-backend return a host error)

Check out /etc/hosts Remember that in some cases you need to use your docker-machine ip (get it from >docker-machine ip) instead of localhost.

I followed all the steps but when i go to https://io-backend it shows me the same as https://io-backend:8080

This problem seems to be dependent on how Docker for Mac (doesn't) manage well the /etc/hosts file. If you install Docker Toolbox it works fine (and can coexist) (Read more at https://medium.com/@itseranga/set-hosts-in-docker-for-mac-2029276fd448)