Processing signed contracts in a state machine: Open Vote example

The LegalLab repository contains a new example that illustrates how Neuro-Feature token state machines can be used to process signed smart contracts. The example implements a simple open voting system that tokenizes each vote, counting ballots within a given time frame, as they are cast. Each ballot is a smart contract signed by a participant. The state-machine of the vote counts accepted ballots, rejects incorrect ballots, and logs events to the Neuro-Ledger for transparency and auditability.

Note: The same architecture as exemplified by the Open Vote set of contracts (Vote + Ballot contracts) can be used in many technically similar (albeit conceptually different) cases. One such example is the tokenization of agriculture, for example, where each cultivation can be tokenized, and it can keep track of its current state transparently (for the end consumer) by processing observations, each observation recorded as a signed smart contract with information about what has occurred. Another example can be the tokenization of medical journals, for interoperability and privacy protection. The journal observes diagnoses and tests being performed, each one recorded as a signed smart contract with the appropriate information.

Vote Contract

The first contract in the Open Voting model (OpenVoteYesNoAbstain.xml), contains the state-machine Neuro-Feature token definition and contract. It defines the basic states of ballot processing. It assumes each ballot contains machine-readable information, as defined by the schema OpenVote.xsd, also downloadable online via its target namespace: https://paiwise.tagroot.io/Schema/OpenVote.xsd.

Note: Each contract containing machine-readable instructions will only be accepted if each Neuron® can validate the XML it contains. This is done by downloading the schema files from the corresponding target namespaces and using these schemas for validation. If the validation does not complete successfully, the contract is automatically rejected.

The states defined in the contract can be illustrated with the following state diagram:

The voting contract allows the creator to pose a question, define if participants are allowed to change their votes, and between what times the vote will be active. Times are defined in UTC. Participants need personal digital IDs with at least a validated country code, personal number and full name. Only one ballot per (Country, Country Code) will be counted. Apart from a Creator, the contract also requires a Certifier, which can be the same as the creator. The Certifier are given rights to cancel (invalidate) an election.

The states a voting procedure passes through are:

• During the Preparing state, the state machine checks if it is paired with a Ballot template that points to it. The Ballot template needs to define a contract reference parameter to the vote, and it needs to enforce the template of the vote to match the template used to create the vote. If one such Ballot template is found, it progresses automatically to the next state. If one is not found, it awaits until such a template is approved on the Neuron®.

• The Pending state, is a state where the vote is prepared, but has not commenced yet. During this state, the present view can be displayed, and links to the vote can be distributed. Any ballots cast during this state will be automatically rejected. Once the time to open the vote has been reached, the state-machine progresses to the next state.

• The Open state is where participants can vote by signing Ballot contracts. If they are signed using the appropriate template, and pointing to the vote, the state-machine will process the ballots. If any errors are encountered, the corresponding ballot is rejected, and error logged. When the finishing time has been reached, the state-machine progresses to the next state.

• The last state is the Closed state. Here, the voting machine is kept alive, to present results, but no ballots are processed, so the tally cannot be changed. Once the expiry time is reached, the state-machine is ended.

During state changes, the creator is notified by XMPP (Instant Chat Message) and e-Mail about the state of the vote. The messages contain links to the vote. These can be distributed to participants of the vote. The vote can also be shown in a browser. If published, voters and other participants can follow the results in real-time.

Ballot Contract

The second contract template is the OpenBallotYesNoAbstain.xml contract. It defines the ballot contract that can be used to participate in any votes generated by the corresponding voting template. The two templates must be paired. So, once the voting template has been proposed and apporved, its ID must be set into the Ballot template contract, before it can be proposed. Once this has been done, it can be proposed and approved accordingly. Then, the pair can be used with as many votes as desired.

The Ballot template defines the Boolean parameters necessary to be able to select Yes, No or Abstain. The Machine-readable part (defined by the https://paiwise.tagroot.io/Schema/OpenVote.xsd namespace) instructs the vote state-machine how the ballot is to be interpreted. The Ballot template has a contract reference parameter of a given name, and it must require a contract reference having a template ID restriction equal to the ID of the voting template. Once the voting state-machine is running, it will provide links to the corresponding Ballot contract template, with these references pre-set, so the user does not need to worry about providing the values for thse references. The user will only scan a QR code to vote.

Approved templates for experimentation

If you want to experiment with the open voting solution described, you can use the following approved contract templates. You can either copy the contract IDs and use in your application, or if you use an App, scan the corresponding QR code to access it.

To create a vote, i.e. define a question partiticpants will vote on, use the following template by scanning the code or entering its ID in the appropriate interface:

The matching Ballot template (which you will not need to scan here directly, as it will be presented pre-filled for you, see below), is:

After scanning the code, a new vote contract will be displayed. Fill in the details (question, if votes can be changed and the time interval the vote will be open; remember the times need to be provided in Universal Time Coordinates, or UTC). Sign the contract, both as Creator and Certifier (unless you want another person to sign as Certifier). Once the vote has been created and been properly signed, a Neuro-Feature token will be created. It will send you an e-mail with a link to the voting results page. The vote only passes slightly the preparation state, as an approved ballot template already exists. The vote page will look something as follows. Note the QR code to the right. It will point to the ballot contract template to use to cast a ballot, and also contain the reference to the current vote pre-filled. All you need to do after scanning the QR-code, is to select how you want to vote.

Note: The vote token is defined to be unique. This means, you can only create one token (one vote) with the same set of parameters. This means, you need to change any of the parameters from previous versions, including the question or time parameters, before you can create additional votes.

Vote Count & real-time presentation

The token that is generated by the vote contract has a present report that displays the current state of the vote. The creator can access the present report from the client used to create the vote contract, and by extension the token. The creator will also get an Instant Chat Message and an e-Mail, containing the present report and current vote count (which would be zero and pending, before the count starts). There will also be a web URL which can be distributed, that will show the vote to any online viewer. The URL will have a format similar to https://sa.id.tagroot.io/NF/a86d6033-b694-7b5e-c8d3-42d5200ec85c@edaler.sa.id.tagroot.io. The ID in the URL corresponds to the ID of the Vote. You can match this ID with the ID displayed for the vote (see below). The present report can be projected and displayed in kiosk mode as well. It will be updated in real-time as votes are counted. The initial view may be something as follows:

Note The QR code in the report can be scanned by participants, and will point to the ballot template, with the vote reference pre-filled in. All the participant needs to do, is vote, and sign the ballot and the vote will be counted. Once the vote closes, the report will be updated accordingly also.

Note: Once the vote closes, the QR code changes. It is no longer pointing to the ballot template, but instead to the token that performed the count. Scanning it will give access to the token, and the reports it publishes.

Presentation Layout

The layout presenting the vote count is generated by the voting token itself, and is part of the vote contract template, and can therefore be reviewed as well. It is an XML Layout format, availble in the OpenVoteResultLayout.xml file. You can edit such XML files and preview the layout using LegalLab as follows:

The variables and script functions used in the layout need to be initialized. This can be done in the Script tab. You can use the initialization script published in the repository: OpenVoteResultLayoutInit.script to generate the view above.

Neuro-Ledger entries recorded

Apart from all entries recorded regarding Digital Identities, Smart Contracts, Tokens and State-Machines, the Open Vote example records several entries by itself. These include:

Entry	Description
BallotCounted	A ballot has been counted.
BallotRejected	A ballot has been rejected.
BallotRevoked	When an older ballot has been revoked because the participant submits a new ballot.
CommentReceived	A comment by a participant has been received.

Note: The vote contract defining the vote, also defines the Neuro-Ledger Collection these entries are recorded in.

The other common Neuro-Ledger collections annotating entries are:

Neuro-Ledger Collections
LegalIdentities	Contains entries related to digital identities, including Neuro-Access digital identities.
Contracts	Contains entries related to smart contracts, including the voting contract and the ballot contracts used during voting.
NeauroFeatureTokens	Contains information regarding Neuro-Feature tokens, including the token definition of the open voting logic.
StateMachines	State-Machine information is recorded in this collection. This includes the open voting process performing the ballot counting and presentation.
StateMachineCurrentStates	Contains current states of different State-Machines.
StateMachineSamples	Contains variable changes as they are persisted by State-Machines. These samples can be used to track the counting process.

#tutorial, #example, #legallab, #contracts, #neuro-feature, #neuro-ledger, #state-machine

New setup tools

A new set of installation tools for the Neuro-Ledger® and Neuron® are available. The old setup files have been obsoleted and will not be updated. The old tools were build using the Wix toolset, which deprecated the version that was used, and upgrading to a newer version was not trivial. Instead, a new set of custom installers have been made. These are all simple executable files, but they can do things that traditional setup tools cannot. They are build around a custom installer available in the IoTGateway repository. It is built around *.package and *.manifest files which are easier to manage and distribute. They are already used through for distributing packages, and so there is little additional work required to build a custom installer. It is furthermore an easy task to build new custom installers, as all you need to do is provide the .package files you want to be installed, and change the installation folder and application name, and you’re done.

The new custom installers have an additional new feature that was difficult when using the old installer: You can install multiple instances of the software (or softwares) on the same machine. You can also individually manage, repair or uninstall them, as required. Each individual instance is its own service, with its own service packages, databases, application data, etc. This also means it is easier to test an installation, as you can do it on your development machine, without it interfering with your other instances or development environments. You can also have multiple development environments in parallel.

Other changes:

• The old name of the Neuron® installer was IoTBrokerSetup.exe and IoTBrokerNoJavaSetup.exe. There is now only one setup file called NeuronSetup.exe. It does not install Java. If Java is necessary for integrations with Java-software, it must be installed separately.

• The old installer installed additional software, such as GraphViz and PlantUML for integration with graphs in Markdown. Such integrations are still possible, but you need to install these softwares separately. They are no longer included by default when installing the Neuron® using the new installer.

You can download the new Windows installers following these links:

• NeuronSetup.exe installs the Neuron®, together with the Neuro-Ledger® and IoT Gateway.
• NeuroLedgerSetup.exe installs the Neuro-Ledger® and IoT Gateway.
• IoTGatewaySetup.exe installs only the IoT Gateway.

Note: For historical reasons, the Neuron® package, when being updated, is still called IoTBroker.package when diseminated in the Neuron® network as an update. The Neuron® consists of the IoTGateway.package, the NeuroLedger.package and the Neuron.package files, joined together as the IoTBroker.package file.

#new, #neuron, #neuro-ledger, #install, #features