Chrome OS Factory Shopfloor Service Specification

History

Version	Date	Summary
1.0 r1	2017/06/20	Initial release
1.0 r2	2018/03/28	Define the format of component domain of DeviceData

Introduction

The Chrome OS Factory Software Platform provides a complete solution for manufacturing flow but there are some data that only the ODM (or CM, contracted manufacturer) can provide, for example serial number, assigned MAC address, SKU information, or the tracking of if a device is ready for shipment. These are usually controlled by the proprietary “shopfloor system” developed by ODM and installed only in manufacturing line. As a result, this must be integrated with the Chrome OS Factory Software Platform.

Different ODMs may implement the shopfloor system in totally different technology, for example using SQL database, web service, or data exchange via CIFS. In order to minimize integration effort and allow most flexibility for partners to choose how the shopfloor system is implemented, Chrome OS Factory Software Platform has defined one virtualized layer of shopfloor, named as “Chrome OS Factory Shopfloor Service” (abbreviated as “Shopfloor Service” in this document).

ODM or CM should implement and maintain the Shopfloor Service to support the interface defined in this document. The service does not need to be open-source nor uploaded to Chrome OS private board overlays source repository. The host running service can be a dedicated server running any OS (Windows, Linux, etc) or simply the one running Chrome OS Factory Server (can be either the legacy server or Umpire & Dome servers). DUTs (Device Under Test) will reach the Shopfloor Service via a bridge inside Chrome OS Factory Server.

Network Topology

A typical setup includes 4 components:

• Device Under Test (DUT, a Chrome OS Device being manufactured)
• Google Chrome OS Factory Server (a server program running on Linux machine)
• Chrome OS Factory Shopfloor Service (A web service maintained by ODM or CM)
• ODM or CM's Shopfloor Backend (The real shopfloor system by ODM or CM).

DUT and Google Chrome OS Factory Server (elements in blue color in diagram) are running code maintained in Google Chrome OS source tree, while Chrome OS Factory Shopfloor Service and Shopfloor Backend (elements in orange color in diagram) are running code maintained by ODM or CM.

For deployment, partner may choose to run Shopfloor Service on same machine running Google Chrome OS Factory Server, on a dedicated Windows or Linux machine, or even directly on the backend. The Google ChromeOS Factory Server just needs to know the URL to Shopfloor Service.

Setting shopfloor service URL for factory server

After Factory Server is properly installed, open the Dome web interface to setup shopfloor service URL for Umpire:

1. Open Dome UI (for example, browser http://<dome_host>:8000).
2. Login and select your project.
3. In Dashboard, find shopFloor in Services list.
4. Change the serviceUrl to the right value.
5. Click DEPLOY.

Umpire will automatically translate localhost to Docker host IP when Docker environment is detected. Otherwise, it would keep its original meaning (usually solved to 127.0.0.1). However, Umpire doesn't translate URLs using numeric IPs like http://127.0.0.1:8000, so that can be used to refer to Docker container itself (if you really want to do this, although that is usually wrong).

Shopfloor Service API

The “Chrome OS Factory Shopfloor Service” must be implemented as a web service using XML-RPC protocol with Nil Extension.

The default recommended port is 8090.

An example implementation of Shopfloor Service in Python can be found here.

An example for how to access Shopfloor Service in Python:

  import xmlrpclib

  service = xmlrpclib.ServerProxy('http://localhost:8090', allow_none=True)
  print('Service Version: %s' % service.GetVersion())

  service.NotifyStart({'serials.mlb_serial_number': '123'}, 'SMT')

We also support Shopfloor Service implemented in JSON-RPC or SOAP via WSDL.

To use JSON-RPC service, add a jsonrpc: prefix when you setup the URL in Chrome OS Factory Software, for example json:http://192.168.0.1:8090. To use WSDL, prefix wsdl:, or make sure your URL ends with wsdl, for example http://192.168.0.1:8070?wsdl.

To verify the server is working properly, use the webservice_utils module:

  import factory_common
  from cros.factory.utils import webservice_utils

  url = 'jsonrpc:http://192.168.0.1:8090'
  service = webservice_utils.CreateWebServiceProxy(url)
  print(service.GetDeviceInfo({}))

If you implement the Shopfloor Service in WSDL+SOAP and found that it is pretty difficult to describe the data structure in parameter and return value (because they are actually Generic Compound Types), there is a special way to implement your service to apply JSON serialization for all input arguments and return value. To do that, prefix a json: in your shopfloor service URL and use webservice_utils to verify. For example:

  import xmlrpclib
  import factory_common
  from cros.factory.utils import webservice_utils

  # Assume your real shopfloor service is here, and all its input and output
  # must be JSON strings:
  real_url = 'http://192.168.0.1:8090'
  proxy = xmlrpclib.ServerProxy(real_url)

  # The input is a JSON string. The output is also JSON, for example
  # '{"vpd.ro.region": "us"}'
  print(proxy.GetDeviceInfo('{}'))

  # The webservice_utils provides 'json:' prefix to filter that.
  url = 'json:http://192.168.0.1:8090'
  service = webservice_utils.CreateWebServiceProxy(url)

  # Input is real variable, and output is real dict, for example
  # {'vpd.ro.region': 'us'}
  print(service.GetDeviceInfo({}))

Data Format: FactoryDeviceData

Most Shopfloor Service functions need a special mapping data structure (struct in XML-RPC, or dict in Python) named FactoryDeviceData. All members should be scalar values.

The member names (or keys of dict) are made in hierarchy like “domain names” - i.e., built with multiple components and concatenated by period “.”. For example, factory.end_SMT is a valid key name with factory as its top domain and end_SMT is the component name for member.

The FactoryDeviceData contains only following members:

• serials: A domain with serial numbers for different components. A typical Chromebook should at least support:
  • serials.serial_number: Serial number of device (printed on case).
  • serials.mlb_serial_number: Serial number of main logic board (mainboard).
• hwid: A value for system HWID if already provisioned.
• factory: A domain with all manufacturing flow generated data. This can be used by shopfloor backend to add its own needed data for flow control. Most Shopfloor Service APIs will also track what has been invoked here, for example:
  • factory.end_SMT: Set to true to indicate the SMT tests are done.

Other fields are not included on purpose, for reducing unnecessary traffic, security and privacy concern. For example, VPD values (especially ECHO codes or registration codes) should never be included.

Data Format: DeviceData

The DeviceData is the structure for return value of Shopfloor Service function calls. The DUT Software will update Device Data (a special dictionary style storage maintained by cros.factory.test.device_data using GetDeviceData and UpdateDeviceData calls).

It is based on FactoryDeviceData, plus few extra domains that DUT won't send back to Shopfloor Service for privacy and performance issues:

• vpd: A domain for setting Vital Product Data. There are two sub domains - ro and rw. For example, vpd.ro.region should be set to the region code of shipping country. Chrome OS devices should follow VPD Field Requirements to setup required VPD values, including:
  • vpd.ro.region: The region code (combination of locale, timezone and keyboard layout, also used for WiFi regulatory) as specified from Chrome OS region database.
  • vpd.rw.ubind_attribute: “User” registration code.
  • vpd.rw.gbind_attribute: “Group” registration code.
• component: An optional domain to specify the SKU information. To specify the number of the specific installed hardware peripheral, use a field in below format:

  component.has_<peripheral_name> = True |  # The DUT has exactly one that
                                            # peripheral.
                                    False |  # The DUT doesn't have that
                                             #     peripheral.
                                    <number>
  

  For example, if the DUT has two cameras (rear camera + front camera), the device data should contain component.has_camera = 2. If the DUT has only one single camera, both component.has_camera = 1 and component.has_camera = True are valid.

**Note: There is no need to specify “device serial number” in vpd domain (ro.vpd.serial_number) because that will be automatically derived from serials.serial_number.

Method: GetVersion

Returns the version of supported protocol.

Parameters:
  None

Returns:
  A string for protocol version. "1.0" for current specification.

Example:
  GetVersion() # Returns "1.0"

All Shopfloor Service implementations following this specification should return string 1.0.

Method: NotifyStart

Notifies shopfloor backend that DUT is entering a manufacturing station.

Parameters:
  - data: A struct FactoryDeviceData representing DUT information.
  - station: A string (case-sensitive) as name of station.

Returns:
  A struct DeviceData for values to update in the device_data.GetDeviceData.

Example:
  NotifyStart({'serials.mlb_serial_number': 'C123'}, 'SMT')
  # Returns {} and device_data.GetDeviceData('factory.start_SMT') is True.

A Shopfloor Service implementation for typical Chromebook usually need to support at least following stations, which is defined by reference test lists:

• SMT: Test in Surface Mount Technology station, to verify main board.
• FAT: Final Assembly Test.
• RUNIN: Run-In Test.
• FFT: Final Functional Test.
• GRT: Google required Test.

For projects that don't plan to do some of the test stations above, they can simply pass and return empty data for that station. Some projects may also choose to add additional stations, but then they have to modify and maintain their own test lists.

When success, DUT software calling this API should automatically set a factory.start_<station> value in DeviceData to True.

Method: NotifyEnd

Notifies shopfloor backend that DUT is leaving a manufacturing station.

Parameters:
  - data: struct FactoryDeviceData
  - station: string (case-sensitive)

Returns:
  A struct DeviceData for values to update in the device_data.GetDeviceData.

Example:
  NotifyEnd({'serials.serial_number': 'A123'}, 'FAT')
  # Returns {} and device_data.GetDeviceData('factory.end_FAT') is True.

Similar to NotifyStart - see that for details about station names.

When success, DUT software calling this API should automatically set a factory.end_<station> value in DeviceData to True.

Note: we've explicitly restricted this function to not sending extra arguments about test results. Ideally test result collection should be done by logging systems (for example, the TestLog in Chrome OS Factory Software) and analyzed separately. If you need to change test flow according to test results, see UpdateTestResult.

Method: NotifyEvent

Notifies shopfloor backend that the DUT has performed an event, usually a check point.

Parameters:
  - data: struct FactoryDeviceData
  - event: string (case-sensitive)

Returns:
  A struct DeviceData for values to update in the device_data.GetDeviceData.

Example:
  NotifyEvent({'serials.serial_number': 'A123'}, 'Finalize')

  Returns {} and device_data.GetDeviceData('factory.event_Finalize') is
  True.

When success, DUT software calling this NotifyEvent should automatically set a factory.event_<event> value in DeviceData to True.

A Shopfloor Service implementation for typical Chromebook need to accept at least following events:

Finalize

Indication that DUT has been finalized, wiped and ready for shipment.

The data argument should not contain fields with privacy concern, for example MAC address or registration codes. If you need to verify those values, write a dedicated test for it.

Refinalize

Indication that DUT has been sent to Outgoing Quality Control (OQC) and now back for reset and wipe.

The data argument should not contain fields with privacy concern, for example MAC address or registration codes. If you need to verify those values, write a dedicated test for it.

Method: GetDeviceInfo

Gets information about the expected configuration for a DUT.

Parameters:
  - data: struct FactoryDeviceData

Returns:
  A struct DeviceData for values to update in the device_data.GetDeviceData.

Example:
  GetDeviceInfo({'serials.mlb_serial_number': 'C123'})
  # Returns {'serials.serial_number': 'A1234', 'vpd.ro.region': 'us'}

Communicates with the backend shopfloor server, and obtains information about the expected configuration of the device, for example VPD values or SKU and component information.

Method: ActivateRegCode

Notifies shopfloor backend that the DUT has deployed a registration code (also known as ECHO codes) successfully.

Parameters:
  - ubind_attribute: A string for user registration code.
  - gbind_attribute: A string for group registration code.
  - hwid: A string for HWID of the DUT.

Returns:
  A struct DeviceData for values to update in the device_data.GetDeviceData.

Example:
  ActivateRegCode('uuu', 'ggg', 'LINK A2C-B3D')

  Returns {} and device_data.GetDeviceData('factory.activate_reg_code') is
  True.

This registration code should be marked as “used” and logged on shopfloor backend, then sent back to Google CPFE for being activated. Due to privacy concern, this code should be NEVER associated with serial number and any other data, so this function is designed very differently - no FactoryDeviceData.

When success, DUT software calling this API should set a factory.activate_reg_code value in DeviceData to True.

Method: UpdateTestResult

Sends the specified test result to shopfloor backend.

Parameters:
  - data: struct FactoryDeviceData
  - test_id: A string as identifier of the given test.
  - status: A string from TestState (case sensitive).
  - details: (optional) A struct to provide more details test results,
    including at least one string member 'error_message' as message
    reported from the error.

Returns:
  A struct DeviceData for values to update in the device_data.GetDeviceData.
  If a member 'action' is included, its value will be used to decide
  how to proceed with testing flow.

Example:
  UpdateTestResult(data, 'smt.type_c_left', 'PASSED') # Returns {}
  UpdateTestResult(data, 'smt.type_c_left', 'FAILED',
                   {'error_msg': 'Unknown'})
  # Returns {'action': 're-run'}

TestState is defined in cros.factory.test.state and the status parameter should be one of the following values: PASSED, FAILED, SKIPPED, or FAILED_AND_WAIVED.

Shopfloor may use this function to indicate what DUT should do next using the action member in returned DeviceData struct. For example to re-run the test, skip, or abort for fault analysis.

For most projects this can be implemented as a dummy function returning empty dict.