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Zebrunner MCloud

Zebrunner MCloud is a Device Farm for automated test execution (Appium) and remote web access by humans to physical devices (Android and iOS) including phones, tablets, and TVs. It is fully integrated into the Zebrunner (Community Edition) ecosystem and can be used both for manual and automated testing.

This repository is the server side of the farm: the docker compose services of STF (a fork of DeviceFarmer/stf with iOS devices and the Zebrunner sign-in), the Selenium/Appium hub mcloud-grid and the nginx in front of them, managed by zebrunner.sh. The devices are connected by mcloud-agent.

Feel free to support the development with a donation for the next improvements.

Zebrunner

System requirements

Requirement Value
Operating System Ubuntu 24.04, macOS
CPU 4+ Cores
Memory 16 Gb RAM
Free space SSD 32Gb+ of free space
  • Docker v27+ with the Docker compose plugin
  • git 2.20.0+
  • openssl with X25519 (OpenSSL 1.1.1+) or Python 3: the setup makes the CURVE keys with them (the LibreSSL of macOS has no X25519, Python 3 is used there)

Run

  1. Clone mcloud and set it up, provide valid protocol, hostname and port:

    git clone https://github.com/zebrunner/mcloud.git && cd mcloud && ./zebrunner.sh setup
  2. Start the services: the setup offers it, otherwise ./zebrunner.sh start.

  3. Open http://hostname:80/stf (the protocol, host and port of the setup).

  4. Sign in: the default mock sign-in asks the user and the password the setup printed (STF_AUTH_MOCK_BASIC_AUTH_* of variables.env), then any name and email; the setup also offers OAuth2 and LDAP, see Sign-in.

  5. Go to Settings, Keys and generate a new Access Token.

  6. Paste the generated token into variables.env as STF_TOKEN.

  7. Restart the services: ./zebrunner.sh restart.

  8. Set up the servers with Android and iOS devices according to mcloud-agent, the same on Linux and macOS. Set STF_STORAGE_TOKEN of mcloud-agent to the STF_STORAGE_TOKEN of variables.env: the STF storage accepts the uploads of the devices with this token only. Set STF_ZMQ_CURVE_SERVER_PUBLIC_KEY and NODE_REGISTRATION_TOKEN of mcloud-agent to the ones of variables.env and add the public key of every device host to STF_ZMQ_CURVE_CLIENT_KEYS, see Authentication of the device hosts.

  9. Use http://hostname:80/mcloud/grid/console to see the connected devices and http://hostname:80/mcloud/wd/hub as the Selenium/Appium hub URL for test automation.

Follow the installation and configuration guide in Zebrunner CE to reuse MCloud components effectively for Test Automation.

The commands of ./zebrunner.sh:

Command What it does
setup writes .env, variables.env and configuration/stf-proxy/nginx.conf from their *.original files, then offers to start the services; the values of the previous setup are kept
start starts the services and shows their URLs, warns while STF_TOKEN is empty; the first start runs setup
stop stops the services, the containers are kept
restart down and start
down stops and removes the containers, the data is kept
shutdown removes the containers, the data and the settings
backup, restore the settings to *.bak and the database to backup/rethinkdb.tar.gz, and back; backup stops the database and the STF units for the copy (the UI and the devices are unavailable meanwhile) and starts them again, a database being written is not copied consistently
version the version of MCloud, the tag of the STF image

Configuration

./zebrunner.sh setup writes the settings from the *.original files, ./zebrunner.sh restart applies their changes. The next setup writes .env again and keeps the values of the variables of variables.env.original in variables.env (but STF_URL and the ZEBRUNNER_* URLs, which come from the protocol, host and port); the other variables added to variables.env are added again after it.

.env, the settings of docker-compose.yml:

Variable Default Description
STF_URL http://localhost:8082 the public URL of MCloud: the protocol, host and port of the setup
STF_PORT 8082 the port of stf-proxy on the host
AGENTS_ADDRESS 0.0.0.0 the host address of the ports the device hosts connect to: ZeroMQ of STF and the grid, see Firewall; the value of the previous setup is kept
AGENT_HOSTS the device hosts (STF_PROVIDER_HOST of mcloud-agent) separated by commas, see Screens of the devices; the setup asks it, the value of the previous setup is kept
LOG_MAX_SIZE, LOG_MAX_FILE 50m, 5 the rotation of the logs of every service (the json-file driver of docker): the size of a file and the number of the files; the values of the previous setup are kept
TAG_NGINX 1.31.7 the tag of nginx
TAG_SELENIUM_HUB 3.1 the tag of public.ecr.aws/zebrunner/mcloud-grid
TAG_RETHINKDB 2.4.3 the tag of rethinkdb
TAG_STF 3.1 the tag of public.ecr.aws/zebrunner/stf
AUTH_SYSTEM auth-mock the sign-in unit of STF: auth-mock, auth-oauth2 or auth-ldap of the setup, auth-zebrunner in Zebrunner CE by default
AUTH_URL auth/mock/ the path of the sign-in: auth/mock/, auth/oauth/, auth/ldap/, auth/zebrunner/

variables.env, the settings of the STF units and of the grid:

Variable Default Description
SECRET generated the secret of the sessions and the access tokens of STF; the setup generates it once, a change of it ends the sessions and invalidates the access tokens (STF_TOKEN too)
STF_STORAGE_TOKEN generated the token of the STF units for the storage routes, the same value as STF_STORAGE_TOKEN of mcloud-agent
STF_TOKEN the access token of the STF user the grid reserves the devices with
NODE_REGISTRATION_TOKEN generated the secret the Appium nodes of the device hosts register in the grid with, the same value as NODE_REGISTRATION_TOKEN of mcloud-agent
STF_URL http://localhost:8082 the public URL of MCloud
STF_ROOT_GROUP_NAME MCloud the root group of STF
STF_ADMIN_NAME, STF_ADMIN_EMAIL admin, admin@zebrunner.com the administrator of STF, the owner of the root group
ZEBRUNNER_LOGIN_URL, ZEBRUNNER_USERINFO_URL the endpoints of Zebrunner IAM for auth-zebrunner, set by the setup of Zebrunner CE
STF_AUTH_MOCK_USE_BASIC_AUTH, STF_AUTH_MOCK_BASIC_AUTH_USERNAME, STF_AUTH_MOCK_BASIC_AUTH_PASSWORD true, mcloud, generated the shared user and password in front of the mock sign-in
OAUTH_AUTHORIZATION_URL, OAUTH_TOKEN_URL, OAUTH_USERINFO_URL, OAUTH_CLIENT_ID, OAUTH_CLIENT_SECRET, OAUTH_SCOPE, OAUTH_DOMAIN the OAuth2 sign-in, asked by the setup; OAUTH_CALLBACK_URL is <STF_URL>/auth/oauth/callback
LDAP_URL, LDAP_BIND_DN, LDAP_BIND_CREDENTIALS, LDAP_SEARCH_DN, LDAP_SEARCH_FIELD the LDAP sign-in, asked by the setup
RETHINKDB_PORT_28015_TCP tcp://rethinkdb:28015 the database of STF
RETHINKDB_ENV_AUTHKEY generated the password of the admin of RethinkDB the STF units connect with, stf-migrate sets it in the database
STF_ZMQ_CURVE_SERVER_SECRET_KEY, STF_ZMQ_CURVE_SERVER_PUBLIC_KEY generated the CURVE key pair of the triproxies of STF, the public key goes to mcloud-agent
STF_ZMQ_CURVE_SECRET_KEY generated the CURVE key of the STF units
STF_ZMQ_CURVE_CLIENT_KEYS the public keys of the device hosts (mcloud-agent) separated by commas: the triproxies accept them only

More settings of STF (e.g. STF_SESSION_TTL_SECONDS, the lifetime of a session, or STF_STORAGE_TEMP_DOWNLOAD_ALLOW, the private networks the apps may be installed from by URL) are described in ZEBRUNNER.md of STF. The settings of the grid (e.g. NODE_ALLOWED_NETWORKS, MAX_NEW_COMMAND_TIMEOUT, MCLOUD_LOG_LEVEL) are described in mcloud-grid, they go to environment of mcloud-grid in docker-compose.yml.

Sign-in

The interactive setup asks the sign-in of STF; Zebrunner CE signs in through Zebrunner IAM (auth-zebrunner) by default, see Zebrunner CE. The values the setup asks are written quoted into variables.env (quotes and backslashes are not supported) and are the defaults of the next setup.

Sign-in Who is the user The setup asks
mock (default) anyone who knows the shared user and password (basic authentication) types a name and an email: whoever knows the name and the email of the admin (STF_ADMIN_*) signs in as the admin, so share the password with the trusted users only nothing, the password is generated and printed
oauth2 the user of an OpenID Connect / OAuth2 provider (Google, Azure AD, Keycloak, GitLab, ...): an email of OAUTH_DOMAIN that the provider does not report as unverified; the admin is the user with the email STF_ADMIN_EMAIL the authorization, token and user info URLs, the client of MCloud at the provider (its redirect URL is <STF_URL>/auth/oauth/callback), the scope (openid email), the domain
ldap the user of the directory with its password the URL, the bind DN and password (empty for an anonymous search), the search DN and the attribute of the user name (uid)

https

./zebrunner.sh setup with the https protocol turns on the ssl of stf-proxy with the certificate of the host: put it into configuration/stf-proxy/ssl/ssl.crt and its key into configuration/stf-proxy/ssl/ssl.key before the setup, which fails without them, for a key of another certificate and for the self-signed pair the repository had (its private key is public). Zebrunner CE gives its own certificate (nginx/ssl of Zebrunner CE, its nginx is in front of stf-proxy): the setup copies it and warns when it is the self-signed one of the repository of Zebrunner CE. shutdown keeps the certificate. stf-proxy passes the scheme of the client to STF (X-Forwarded-Proto, the one of a proxy in front of it when there is one), so the session cookie is Secure behind https. The ssl settings allow TLS 1.2 and 1.3 only.

Zebrunner CE

Zebrunner CE runs ./zebrunner.sh setup of its mcloud folder with ZBR_INSTALLER=1 and its settings: the URL of Zebrunner CE, its nginx is in front of stf-proxy (its port STF_PORT is 8082, the port of Zebrunner CE belongs to its nginx), its certificate, the sign-in through Zebrunner IAM. ./zebrunner.sh setup run in the mcloud folder of Zebrunner CE keeps them (from backup/settings.env of the last setup of Zebrunner CE) and asks only the admin and the sign-in: zebrunner (Zebrunner IAM), mock, oauth2 or ldap; the setup of Zebrunner CE keeps that sign-in. Restart the services after it: ./zebrunner.sh restart.

Security headers

stf-proxy adds Referrer-Policy: no-referrer, X-Content-Type-Options: nosniff, X-Frame-Options: SAMEORIGIN and Content-Security-Policy: frame-ancestors 'self' to every response and removes X-Powered-By: MCloud is not embedded into the pages of other sites. A site that frames MCloud (e.g. another host of Zebrunner) needs frame-ancestors 'self' https://<host> instead and no X-Frame-Options in configuration/stf-proxy/nginx.conf.

Authentication of the device hosts

The device hosts (mcloud-agent) connect to ZeroMQ of STF (the triproxies), their Appium nodes register in the grid. Neither has an authentication of its own: anyone who reaches their ports reads the events of all the devices or sends commands to them, and a node registered in the grid gets the sessions of its device with their capabilities (the personal zebrunner:STF_TOKEN too). So ./zebrunner.sh setup turns the authentication on:

  • the triproxies accept only the clients with a known CURVE key (ZeroMQ of STF): the STF units and the device hosts of STF_ZMQ_CURVE_CLIENT_KEYS, the traffic is encrypted. ./zebrunner.sh setup makes the keys (X25519, as stf curve-keygen) with openssl or, where it has no X25519, with patch/curve_keygen.py, the same as of mcloud-agent;
  • RethinkDB has a password, RETHINKDB_ENV_AUTHKEY, its web console is off and its port is not published: only the STF units of the server use the database;
  • the grid registers only the Appium nodes with NODE_REGISTRATION_TOKEN of variables.env, which the setup generates (Node registration of mcloud-grid), and sends it with its requests to them: the Appium of a device answers the grid only, the devices are used through /mcloud/wd/hub and reserved in STF. Set it as NODE_REGISTRATION_TOKEN of every mcloud-agent.

A device host makes its own key pair (mcloud-agent prints its public key): add the public key to STF_ZMQ_CURVE_CLIENT_KEYS of variables.env, separated by commas, and run ./zebrunner.sh restart. The removal of a key disconnects its device host.

The device hosts need mcloud-agent of the same MCloud release with STF_ZMQ_CURVE_SERVER_PUBLIC_KEY, NODE_REGISTRATION_TOKEN and STF_STORAGE_TOKEN; the others cannot connect.

Screens of the devices

The screen of a device is a WebSocket of its STF provider on the device host, which the browser opens through stf-proxy: /d/<device host>/<serial>/<port>/. stf-proxy serves it only:

  • for a device host of AGENT_HOSTS of .env (the STF_PROVIDER_HOST of every mcloud-agent), any other host gets 403; without AGENT_HOSTS no screen is served;
  • on a port 1024-65535;
  • for a signed-in user of STF: stf-proxy asks stf-api about the session cookie (or an access token) of the request, 401 without one.

The setup asks AGENT_HOSTS and writes configuration/stf-proxy/agent-hosts.conf from it, so does ./zebrunner.sh start: change AGENT_HOSTS of .env and run ./zebrunner.sh restart for a new device host (also in Zebrunner CE).

Firewall

The ports of the host and who needs them; close the others:

Port Service Clients
STF_PORT stf-proxy the users, the tests, the device hosts (the storage, the screens)
7160, 7250, 7260, 7270 (AGENTS_ADDRESS) ZeroMQ of STF (stf-triproxy-app, stf-triproxy-dev) the device hosts
4446 (AGENTS_ADDRESS) mcloud-grid the device hosts (Appium registers to the grid); the tests use /mcloud/wd/hub of STF_PORT

AGENTS_ADDRESS publishes these ports on one address of the host, e.g. the one of the network of the device hosts. A device host publishes the ports of its devices for the server (stf-proxy serves the screens to the users) and for the remote ADB of the users, see mcloud-agent.

Basic authentication of the grid

See configuration/stf-proxy/htpasswd.

Files and secrets

variables.env, backup/settings.env, the key of the certificate (configuration/stf-proxy/ssl/ssl.key), the archive of the database (backup/rethinkdb.tar.gz) and their backups hold the secrets of the deployment: setup, start, backup and restore keep them readable for their owner only (600). Run zebrunner.sh as the user of the deployment; a sudo ./zebrunner.sh gives the files it writes back to the owner of the folder.

Services

All the services are in the external docker network infra, which ./zebrunner.sh start creates.

Service Image What it does
stf-proxy nginx the entry point on STF_PORT: STF, the grid under /mcloud, the static files of the grid console
mcloud-grid public.ecr.aws/zebrunner/mcloud-grid the Selenium/Appium hub of the devices, also on the port 4446 of the host (AGENTS_ADDRESS)
rethinkdb rethinkdb the database of STF, the volume stf-db-volume, with the password RETHINKDB_ENV_AUTHKEY and without its web console, not published on the host
stf-migrate public.ecr.aws/zebrunner/stf creates and updates the tables of the database, the other STF units start after it
stf-app, stf-auth, stf-api, stf-websocket public.ecr.aws/zebrunner/stf the UI, the sign-in, the REST API and the websocket of STF
stf-processor001, stf-reaper, stf-api-groups-engine public.ecr.aws/zebrunner/stf the device events, the heartbeats and the groups of STF
stf-triproxy-app, stf-triproxy-dev public.ecr.aws/zebrunner/stf the message brokers of the STF units and of the devices, the ports 7160 and 7250-7270 of the host (AGENTS_ADDRESS)
stf-storage-temp, stf-storage-plugin-apk, stf-storage-plugin-image public.ecr.aws/zebrunner/stf the storage of the apps and screenshots, the volume stf-temp-volume; protected by STF_STORAGE_TOKEN

Every service has a healthcheck (docker ps shows unhealthy for one that stopped answering): the STF units with an HTTP port and the triproxies (a TCP connection), stf-proxy, rethinkdb, mcloud-grid (the one of its image), and the units without a port, stf-processor001, stf-reaper and stf-api-groups-engine: they are healthy while they are connected to their ZeroMQ brokers and to RethinkDB (stf-migrate runs once); stf-proxy starts once stf-app is healthy. Docker restarts a service when it exits, not when it is unhealthy. The logs of every service are rotated (LOG_MAX_SIZE, LOG_MAX_FILE).

Endpoints

Endpoint Content
/stf the UI of STF
/api/v1/ the REST API of STF, with an access token
/mcloud/wd/hub the Selenium/Appium hub URL
/mcloud/grid/console the grid console with the devices
/mcloud/grid/admin/DevicesServlet the devices of the grid as JSON: their status and sessions
/mcloud/grid/admin/AllSessionsServlet the active sessions as JSON
/mcloud/grid/admin/MetricsServlet the Prometheus metrics of the grid
POST /mcloud/grid/admin/TerminateSessionServlet terminates the session of a device, see mcloud-grid

Upgrade

An MCloud release works with mcloud-agent of the same release only (the images of the device hosts, the authentication of the device hosts): update the server and all the device hosts together.

  1. Update the repository: git pull.
  2. Run ./zebrunner.sh setup: it keeps the settings of the previous setup and generates the missing ones, check the settings of mcloud-agent it prints.
  3. Update mcloud-agent of every device host to the same release, see its README.
  4. Restart the services: ./zebrunner.sh restart; stf-migrate updates the tables of the database.

Troubleshooting

docker logs <service> shows the log of a service, docker ps the unhealthy ones (see Services).

Symptom Cause and fix
./zebrunner.sh start fails to pull: denied: Your authorization token has expired or 403 Forbidden from public.ecr.aws an expired login to public.ecr.aws in ~/.docker/config.json of the user: the images are public, docker logout public.ecr.aws (or log in again: aws ecr-public get-login-password --region us-east-1 | docker login --username AWS --password-stdin public.ecr.aws)
the pull fails with manifest unknown the tag of TAG_* of .env is not published: the tags of .env.original of the current MCloud
the devices are in STF, not in /mcloud/grid/console; mcloud-grid logs Could not get the device '<udid>' from STF (HTTP 401), the node is not registered. STF_TOKEN of variables.env is empty or not an access token of STF: generate one (STF, Settings, Keys), set it and ./zebrunner.sh restart (start warns while it is empty)
mcloud-grid logs Node <url> has no or another NODE_REGISTRATION_TOKEN than the hub, so it is not registered. NODE_REGISTRATION_TOKEN of the device host differs from variables.env: set the one of variables.env in mcloud-agent and run its ./zebrunner.sh ansible, zebrunner-farm restart
mcloud-grid logs Node <url> is not reachable from the hub the hub does not reach the Appium port of the device host: STF_PROVIDER_HOST of mcloud-agent and the firewall of the device host
the device host is up, its devices are not in STF (the stf container of an Android device restarts after Providing all 0 of 1 device(s)); stf-triproxy-app or stf-triproxy-dev logs Refused the ZeroMQ client <address> with the unknown key "<key>" the public key of the device host is not in STF_ZMQ_CURVE_CLIENT_KEYS of the running services: add the one ./zebrunner.sh curve-key of mcloud-agent prints to variables.env and ./zebrunner.sh restart (a change of variables.env needs it), then zebrunner-farm restart on the device host for its iOS devices; a device host with another STF_ZMQ_CURVE_SERVER_PUBLIC_KEY than variables.env is not let in either, see Authentication of the device hosts
the screen of a device stays gray, /d/<device host>/... answers 403 the device host is not in AGENT_HOSTS of .env: add it and ./zebrunner.sh restart, see Screens of the devices (401: the user is not signed in)
the screenshots or the app installs of the devices fail with 401 / 403 STF_STORAGE_TOKEN of the device host differs from variables.env
configuration/stf-proxy/agent-hosts.conf is not writable (Permission denied) the file was written by root (sudo ./zebrunner.sh ...): rm -f configuration/stf-proxy/agent-hosts.conf and ./zebrunner.sh restart; run zebrunner.sh as the user of the deployment
The certificate of Zebrunner CE (../nginx/ssl/ssl.crt and ssl.key) cannot be copied the key of Zebrunner CE is readable for root only (e.g. written by certbot): make it readable for the user of the setup (its group and chmod 640) instead of sudo ./zebrunner.sh setup
a device of a gone device host is not removed by Settings, Devices of STF (nothing happens) the removing filters of the page skip the devices that are controlled, booked or annotated, and a device whose host went away during a session stays controlled: set Controlled (and the others) of the filters to Any
macOS (Docker Desktop): ./zebrunner.sh start hangs, stf-proxy stays Created, docker inspect stf-proxy does not answer the port forwarding of Docker Desktop hangs (seen after a failed start): docker desktop restart (or quit and start Docker Desktop), then ./zebrunner.sh start
stf-processor001, stf-reaper or stf-api-groups-engine is unhealthy the unit lost its ZeroMQ brokers (stf-triproxy-*) or RethinkDB, docker does not restart an unhealthy unit: see the state and the logs of the brokers and of rethinkdb, then ./zebrunner.sh restart

Components

  • mcloud-agent - Device Farm agent for connecting Android and iOS devices including phones, tablets, and TVs over USB or Wi-Fi, Android emulators and iOS / tvOS simulators (macOS) via Linux or macOS.
  • mcloud-device - Dockerized STF provider image for Android and iOS devices.
  • mcloud-grid - Enhanced Selenium Grid for automating physical devices and emulators/simulators via Appium.
  • stf - the STF of MCloud with iOS devices and the Zebrunner sign-in.
  • appium - Enhanced Appium image with low-level video recording and local storage for ipa/apk artifacts.

Development

Target What it checks Needs
make check everything below, as CI runs it
make lint tests/lint.sh: yamllint, actionlint, pymarkdown, shellcheck, shfmt, ruff, the text files, docker compose config with the *.original settings Python 3; on macOS brew install hadolint
make test tests/zebrunner_test.sh and tests/utility_test.sh: the commands of zebrunner.sh on a copy of the repository with a docker stub bash
make docker tests/compose_test.sh: the setup, the start and the endpoints of the services, then their shutdown; TAG_STF=<tag> TAG_SELENIUM_HUB=<tag> make docker checks other images Docker, no other MCloud on the machine

The tests write JUnit XML into $JUNIT_DIR when it is set. CI (.github/workflows/ci.yml) runs the jobs lint, tests (Linux and macOS) and docker on the pushes and pull requests.

The end-to-end test of the farm (.github/workflows/e2e.yml, on the pushes and pull requests, every night and on demand) runs on a GitHub runner with KVM:

  1. tests/e2e/build-images.sh builds the images of the farm with an Android device from the develop branches of their repositories with the tags of .env.original and of mcloud-agent; only the uploader is pulled from public.ecr.aws/zebrunner (artifacts-uploader is private). The inputs ref (all the repositories) and refs (single ones: STF_REF=fix/x MCLOUD_AGENT_REF=feat/y) of a manual run take other branches, as E2E_REF and E2E_REFS or <REPOSITORY>_REF of the script.
  2. tests/e2e/emulator.sh starts with an Android emulator (android-emulator-runner) and relays its adb to the containers.
  3. tests/e2e/farm_test.sh sets up and starts MCloud of this checkout, MinIO for the artifacts and a device host of mcloud-agent with the emulator, then checks the containers, the device in STF and in the grid, an Appium session with an app, the screen of the device in STF, the upload of a file to STF and the artifacts of the session (the video too) in S3.

The logs of every container and of the emulator are the artifact e2e of the run (with JUnit XML). tests/e2e/farm_test.sh changes the machine (the ports, udev, zebrunner-farm), run it only on disposable machines.

The conventions of the style, the formatting and the tooling of this repository are in CONVENTIONS.md, the same in all the MCloud repositories. The rules of this repository:

  • docker-compose.yml takes the image tags (TAG_*) and the ports from .env, the settings of the services from variables.env; ./zebrunner.sh setup writes both from .env.original and variables.env.original, which keep the defaults. make lint checks docker compose config with the *.original files.
  • Every image is pinned by its TAG_* in .env.original, the table of .env shows the same default (both checked by make lint).
  • zebrunner.sh and patch/*.sh are host scripts: the interface of Zebrunner CE (ZBR_INSTALLER, the ZBR_* settings, SHUTDOWN_CONFIRMED, .disabled) and the commands stay compatible.
  • The static files of the Selenium grid console (configuration/stf-proxy/grid/) are kept byte for byte: generated of tests/lint_project.sh and unset formatting in .editorconfig.
  • A test of the services goes to tests/compose_test.sh (DOCKER_TESTS), a test of the commands of zebrunner.sh without docker to tests/zebrunner_test.sh.

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Apache License 2.0

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