Iroha 2 requirements

• List of preconditions which must be satisfied before the use case can be applied
• Each precondition should be defined as the point in the list

Use case flow

1. The enumerated list of actions, which describes the interaction between actors step by step
2. Each step should involve a single actor as an object of the action
3. Each step can involve one or more actors as a subject of the action
4. Each use case can involve other use cases as dependencies by include or extend relationships

• One or more results of successfully finished use case

• List of alternative flows that can happen with the use case.
• Each entry should have the link to the step of the main use case flow when the alternative can occur
  • If needed, each entry can contain sub-entries
• Each entry should describe the consequences of the alternative flow

• List of exceptions that can happen during the use case flow, which can prevent it to be successfully finished
• Each entry should have the link to the step of the main use case flow when the exception can occur
  • If needed, each entry can contain sub-entries
• Each entry should describe the consequences of the exception

• The administrator has configured environment for running Iroha executables
• The administrator has prepared the genesis block

Use case flow

1. The administrator launches the command to run Iroha peer and providing the path to the genesis block description
2. The Iroha peer read and validates the genesis block configuration
3. The Iroha peer starts the Iroha network according to the configuration in the genesis block
4. The Iroha peer provides "successfully started" report to the administrator

• The Iroha network is running
• The administrator has access to the root account of the network

N/A

• At step 2, in case of the invalid genesis block, the Iroha peer shows corresponding error messages to the administrator and halts the network creation process

• The Iroha network is running
• The administrator has access to the account with permissions of adding peers to the network

Use case flow

1. The administrator configures and starts the new peer
2. The administrator prepares the transaction with instruction to add the new peer
3. The administrator sends the prepared transaction to the existing Iroha peer (<<include>> FR0100)
4. The existing Iroha peer initiates connection with the new Iroha peer
5. The new Iroha peer synchronizes the block-storage with existing Iroha peers
6. The new Iroha peer start functioning as fully functional peer in the current Iroha network

• The new peer is added into the network

• On step 5, if the synchronization cannot be finished for some reason, the new Iroha peer cannot join the network; use case stops

• The administrator has access to the account with permission of removing peers form the network

Use case flow

1. The administrator prepares the instruction to remove the peer from the Iroha network
2. The administrator sends the transaction with the prepared instruction to the Iroha peer
3. The Iroha peer confirms the execution of the instruction

• The target peer is removed from the current Iroha network and all processes in consensus continues without it

Use case flow

• The administrator has access to account with permissions to change the network configuration by sending the corresponding instruction

Use case flow

1. The administrator prepares the data for the instruction for changing the overall Iroha network configuration
2. The administrator sends the transaction with prepared instruction to the Iroha peer (<<include>> FR0100)
3. The Iroha peer return the results of instruction execution to the administrator.

• The network configuration is changed correspondingly

N/A

• The administrator has access to the maintenance endpoint of the target Iroha peer

Use case flow

1. The administrator connects to the maintenance endpoint of the target Iroha peer
2. The administrator performs requests to change required parameters of the target Iroha peer
3. The Iroha peer returns result of change operation to the administrator

• The configuration of the target Iroha peer was changed

• On step 3, if the value of changed configuration parameter is out of the limit, the Iroha peer will return "wrong parameter value" error status to the administrator; use case flow stops.

• The user has an account in the Iroha network
• The user has prepared the transaction for sending; transactions can consist of several instructions
• The user has permissions to execute all instruction included in the transaction
• The Iroha network is working in normal condition

Use case flow

1. The user sends the transaction to the Iroha peer through the API
2. The Iroha peer receives the transaction and validates its contents
3. The Iroha peer checks that the user's account have enough permissions to run all instructions included in the transaction
4. The Iroha peer executes the transaction by applying it to the current block
5. The Iroha peer returns the result of the operation to the user

• The transaction is successfully executed and applied to the network state

• On step 4, if the current user's account is multi-signature, the result of the transaction will be applied to the block-store only when the number of signatures will reach the current quorum value. In other cases, the Iroha peer will return "pending" status as a response on step 5.

• On step 2, one of the instructions has invalid structure, the Iroha peer returns an error message with description to the user and stops the flow
• On step 3, if the user's account does not have required permissions to execute one of the instructions, the Iroha peer returns information about that error and stops the flow
• On step 3, in case of a multi-signature transaction, if the instruction signed using the key pair, which was already used for signing that instruction, the Iroha peer will return "already signed" error status and stop the flow

• The user has permission to create accounts

Use case flow

1. The user prepares information about the account that should be created, which includes name, domain, the public key and permissions list
2. The user prepares instruction to send to the Iroha network according to the prepared information
3. The user sends the transaction with the instruction to the Iroha peer (<<include>> FR0100)
4. The Iroha peer returns the result of the instruction execution to the user

• The new account in the Iroha network is created

• On step 3, if the account with the provided name or public key already exists in the network, the Iroha peer will return "already exists" error status; user case flow will stop.

• The user has access to the Iroha account with permissions to change permissions of the target account

Use case flow

1. The user prepares information about set of permissions, which should be enabled or disabled for the target account
2. The user prepares instruction to send to the Iroha network according to the prepared information
3. The user sends the transaction with the instruction to the Iroha peer (<<include>> FR0100)
4. The Iroha peer returns the result of the instruction execution to the user

• The permissions of the target account was changed correspondingly

• On step 4, if the user disables the permission which is not enables on the target account, the Iroha peer return "Permission is not enabled" error status; use case flow stops
• On step 4, if the user enables the permission which is already enabled on the target account, the Iroha peer return "Permission already enabled" error status; use case flow stops

• The user has access to his/her account in the Iroha network
• The user's account has permissions to provide grantable permissions

Use case flow

1. The user prepares the instruction to grant one or more permissions to another account
2. The user sends the transaction with the prepared instruction to the Iroha peer (<<includes>> FR0100)
3. The Iroha peer returns the result of the instruction to the user

• The permission was granted to another account

• On step 3, if the user does not have permission to grant permissions to other accounts, the Iroha peer will return "Not permitted" error status; use case flow stops

• The user has permissions to send complex instructions with DSL sequence inside
• The user has permissions to execute each instruction inside the list of DSL sequence

Use case flow

1. The user builds the DSL sequence for the complex instruction
2. The user prepares the complex instruction to send to the Iroha peer
3. The user sends the complex instruction to the Iroha peer (<<include>> FR0100)
4. The Iroha peer returns the results of complex instruction execution to the user

• The complex instruction was executed and applied to the Iroha network

• On step 4, of there is not enough permissions to execute whole DSL sequence, the Iroha peer will return "not enough permissions" error status; use case flow stops.

• The user has permissions to execute requested instruction

Use case flow

1. The user prepares the instruction parameters according to his/her needs
2. The user sends the transaction with the instruction into the Iroha peer (<<includes>> FR0100)
3. The user uses the same connection for obtaining the status of the instruction finalization
4. The Iroha peer sends updates about the instruction finalization status to the user
5. The user receives the "successfully finalized" status about the instruction

• The instruction is accepted and finalized in the block-storage
• The user did not spend additional resources for redundant network connections and requests

• At step 4 if the instruction cannot pass the validation, the user would not get the "successfully finalized" status; instead, he/she will get the "invalid instruction" status.
• At step 4 if the network is in "bad" condition, the user would get the "successfully finalized" status eventually, when the network will return in a "good" state.

• The user have permission to create new MST accounts

Use case flow

1. The user prepares information about new account, including list of signatories and quorum of signatures
2. The user creates new account in the Iroha network (<<include>> FR0101)
3. The user receives result of new account creation from the Iroha peer

• The new MST account with defined list of signatories and quorum is created

• On step 3, if amount of signatories in the list is lower, than quorum, the Iroha peer returns "Not enough signatories" error; use case flow stops

• The user have access to the account with permissions to control the target MST account

Use case flow

1. The user prepares the instruction with needed parameters for changing the quorum value
2. The user sends the transaction to the Iroha peer (<<include>> FR0100)
3. The Iroha peer returns the results of instruction execution

• The quorum for the target MST account was changed

• If the new quorum is higher than amount of signatories, the Iroha peer will return "Not enough signatories" error message; use case flow stops.

• The user has permissions to change the list of signatories to the required account
• The user has key pair for adding/deleting a signatory to/from the selected account

Use case flow

1. The user prepares the instruction of adding/deleting signatories for sending
2. The user sends the transaction with the instruction to the Iroha peer (<<include>> FR0100)
3. The user receives the response from the Iroha peer

• List of signatories for the selected account was changed correspondingly

• On step 2, if the signatory with the current key pair exists in the list of signatories in the target account, the Iroha peer will return "already added" error status; use case flow stops.

• There is a multi-signature account in the Iroha network
• The user has access to the one or many key pairs for the multi-signature account
• The current amount of signatures to the multi-signature transaction is lower than a current quorum value

Use case flow

• Amount of signatures in the signed instruction increased by 1 signature
• Signed instruction disappears from the list of pending instructions for the current user's account

• The user has permissions to change the conditions for the target multi-signature account

Use case flow

1. The user requests the list of currently configured conditions for the target multi-signature account
2. The user prepared the instruction with the list of conditions to be added/removed
3. The user sends the transaction with the instruction to the Iroha peer (<<include>> FR0100)
4. The Iroha peer sends the response to the user

• The list of conditions for the target multi-signature account was changed correspondingly

• The user has permissions to change the conditions (or some other, to discuss) for the target multi-signature account

Use case flow

1. The user prepared the instruction with the map of public keys and weight correspondence (e.g. key1 → 50, i.e. key2 → 25, key3 → 25)
   and the target quorum (e.g. 50 so that it is needed either to sign upcoming transactions of the user with either key1 or both key2 and key3)
2. The user sends the transaction with the instruction to the Iroha peer (<<include>> FR0100)
3. The Iroha peer sends the response to the user

• The list of signatories weights and target quorum for the target multi-signature account was changed correspondingly

• The user has access to account with permissions to change data payload related to the target account

Use case flow

1. The user prepares the key and value of the data payload for forming the corresponding instruction
2. The user sends the transaction with prepared instruction to the Iroha peer (<<include>> FR0100)
3. The Iroha peer returns results of instruction to the user

• The data payload associated with the target account was changed correspondingly

• On step 2, if there was no such key associated with the target account, the key will be created 
• On step 2, if some value is already associated with the provided key, the value will be overwritten

• On step 2, if the size of payload data exceeds limit, the Iroha peer will return the "Too large data" error message; use case flow stops.

• The user has access to account with permissions to perform required instruction

Use case flow

1. The user prepares the instruction for the required operation and attached the payload to the instruction
2. The user sends the transaction with prepared instruction to the Iroha peer (<<include>> FR0100)
3. The Iroha peer returns results of instruction execution to the user

• The instruction with attached payload successfully executed and payload saved in the block storage

N/A

• On step 2, if the size of payload data exceeds limit, the Iroha peer will return the "Too large data" error message; use case flow stops.

• Iroha 2 whitepaper
• Generic functionality of Iroha

• User has access to the account with permissions, which allows to get results of target query

Use case flow

• User receives the response with the requested data

• On step 2, if the query was formed not correctly (for example, because of problems with the client library) the Iroha peer returns error with result of validation, use case execution stops.
• On step 3, if the user's account does not have enough permissions, the Iroha peer returns error with corresponding status, use case execution stops.

Use case flow

Use case flow

• The user has permissions to request the list of pending transactions

Use case flow

• The user has the list of currently pending instructions

• On step 3, if there are no currently pending transactions, the Iroha peer will return "empty response" status

• The user has permissions to request a list of conditions to the target multi-signature account

Use case flow

1. The user prepares query for requesting a list of currently configured conditions of signing for the target multi-signature account
2. The user sends the query to the Iroha peer (<<include>> FR0200)
3. The user receives the list of currently configured conditions of signing for the target multi-signature account

• The user received the list of conditions for the target account

• On step 3, if there are no currently configured conditions, the Iroha peer will return "empty response" status
• On step 3, if the account is not multi-signature, the Iroha peer will return "not applicable" status

• The user has permissions to request the block by its number

Use case flow

• The user receives the requested block from the blockstore

• On step 3, if there are no block specified, the Iroha peer will return "error/no such block" response

• The user has permissions to request blocks (subscription, can be separate permission or from <<include>> FR0205)

Use case flow

• The user has got stable channel for continuous block obtaining, which can be used for getting all new blocks on the current peer until the connection will be interrupted

N/A

• The user has permissions to request the list of pending transactions (subscription, can be separate permission or from <<include>> FR0203)

Use case flow

• The user has got stable pending transactions perception channel and newly arriving pending transactions

• The user has permissions to get results of the target query

Use case flow

1. The user prepares request data for the target query
2. The user establishes permanent connection to the Iroha peer and sends the query
3. The Iroha peer confirms the connection and start sending updates on the query results until the user closes the connection
4. The user receives the results and performs continuous analysis of the payload

• The user has continuous results of query execution

• The user has permissions to get results of the target query

Use case flow

1. The user prepares request data for the target query
2. The user sends the query to the Iroha peer (<<include>> FR0200)
3. The Iroha peer returns response containing result of the query as well as the Merkle proof of its validity and relation to the current block-store
4. The user receives the response and validates the correctness of the data by checking Merkle proof and obtained data

• The user has result of the query request with merkle proof of its validity

Use case flow

<<extends>> FR0200, substitutes step 4:

1. The Iroha peer collects data from the block storage at the moment, requested in the query

• The user received the requested information about the information in block store on the provided date

• The user has permissions to perform the query
• The user has list of conditions which need to be used for filtering accounts

Use case flow

1. The user prepares the query and adds the filtering setup to the query body
2. The user sends query to the Iroha peer (<<include>> FR0200)
3. The Iroha peer returns result of the query execution to the user

• The user has the list of accounts which satisfies entered filter

• On step 1, the user can include the query to the DSL sequence as a part of the complex instruction

• On step 3, if the user does not have enough permissions, the Iroha peer returns "not enough permission" error status; the use case flow stops.

• The user has access to account with permissions to retrieve data payload related to the target account

Use case flow

1. The user prepares the target account identifier for forming the corresponding query
2. The user sends the transaction with prepared query to the Iroha peer (<<include>> FR0200)
3. The Iroha peer returns results of query to the user, which contains the list of keys, associated with the target account

• The user acquired list of keys of data payload associated with the target account 

N/A

• On step 2, if there is no keys associated with the target account, the Iroha peer will return "No data" status message; use case flow stops.

• The user has permissions to perform the target query
• The user has list of conditions which need to be used for filtering transactions (optionally)

Use case flow

1. The user prepares the query for getting list of transactions and adds the filtering data to the query body
2. The user sends query to the Iroha peer (<<include>> FR0200)
3. The Iroha peer returns result of the query execution to the user

• The user has the list of transactions which satisfies the predefined filter with pagination

• On step 1, the filtering data can be optional; in that case the Iroha peer will return list of all transactions without any filtering
• On step 1, the user can also include paging-related request into the query, in that case the Iroha peer will return the data correspondingly

• On step 3, if the user does not have enough permissions, the Iroha peer returns "not enough permission" error status; the use case flow stops.
• On step 3, if the user provided setup of filtering, which results in empty response, the Iroha peer will return "Empty response" status message; use case stops,
• On step 3, if the user provided incorrect pagination-related request part, the Iroha peer will return "Incorrect pagination request" error message; use case stops.

• The user has permissions to perform the target query of getting list of incoming transactions
• The user has list of conditions which need to be used for filtering transactions

Use case flow

1. The user prepares the query for getting list of incoming transactions and adds the filtering data to get only incoming transactions
2. The user sends query to the Iroha peer and subscribes on the results (<<include>> FR0208)
3. The Iroha peer continuously returns result of the query execution to the user
4. The user processes the incoming results of the query
5. Eventually, the user interrupts the subscription with the Iroha peer, which stops the flow of data about incoming transactions

• The user has all incoming transactions during the period when the subscription was active

• On step 1, the user can configure list of accounts, which should be used as filter for the query

N/A

• The user has permissions to setting up triggers in the Iroha network
• The user has permissions to execute all instructions and queries which are included into the trigger body

Use case flow

• The trigger was configured and ready to fire

• The trigger was created and configured as "manual" by the FR0300
• The user has permissions to fire the trigger
• The user has ID of the target trigger

Use case flow

1. The user prepares the instruction to fire the target trigger
2. The user sends the instruction to the Iroha peer (<<include>> FR0100)
3. The Iroha peer returns result of the target trigger execution

• All instructions from the trigger body was executed and applied to the block storage

• On step 3, if user does not have permissions to run all instructions in the Trigger, the Iroha peer returns "not enough permissions" status; use case flow stops.

• The trigger was created by the FR0300
• The user has permissions to remove the trigger
• The user has ID of the target trigger

Use case flow

1. The user prepares the instruction to remove the trigger
2. The user sends the instruction to the Iroha peer (<<include>> FR0100)
3. The Iroha peer returns results of the instruction to the user

• The target trigger was removed from the list of active triggers

• On step 3, if the user does not have enough permissions, the Iroha peer will return "not enough permissions" error status; use case flow stops

• The network administrator have access to the account with permissions to configure fees in the current Iroha network

Use case flow

1. The network administrator prepares the business-level description of the fee configuration
2. The network administrator sets up the fee configuration using the format (or DSL) used in Iroha
3. The network administrator prepares the instruction to change fee in the Iroha network
4. The network administrator sends the prepared instruction to the Iroha peer (<<include>> FR0100)
5. The Iroha peer returns results of the instruction to the user

• The fee configuration was changes according to the provided data

• On step 3, if the user does not have enough permissions, the Iroha peer will return "not enough permissions" error status; use case flow stops

• The user has access to the account with permissions to transfer assets to other account

Use case flow

1. The user prepares the information about needed transfer of assets
2. The user sends the query to the Iroha peer in the aim to get the needed structure of transaction, including all required fees (<<include>> FR0200)
   1. The response also contains the time frame until the provided information will be relevant.
3. The user creates the transaction with all required instructions included within the provided time frame
4. The user sends the prepared instruction to the Iroha peer (<<include>> FR0100)
5. The Iroha peer returns results of the instruction to the user

• The transfer instruction was successfully applied, together with all needed instructions for fees deduction.

• On step 3, if the time frame has passed, the user needs to request the information about fees again in the aim to create correct transaction

• On step 3, if user sends the transaction within the time frame, there is a chance that fees will be changed and the transaction will be rejected; use case flow stops.

• The user has need to delegate full or partial control over the account to another account
• (optionally) The user wants to limit the delegation period by time

Use case flow

• The control over the user's account was delegated to the target account

• The initial user has access to the target account in the Iroha network with permissions to configure inheritance
• The descendant user has access to another account in the Iroha network with permissions to accept the inheritance

Use case flow

1. The initial user prepares the instruction to configure inheritance rules
2. The initial user sends the transaction with the prepared instruction to the Iroha peer (<<include>> FR0100)
3. The Iroha peer responds with the result of the instruction to the initial user
4. Eventually, if the account of the initial user has no activity during the configured time period, the Iroha peer adds the key pair of the account of the descendant user to the list of signatories of the target account.
5. The descendant user receives rights to control the target account with its own key pair

• The descendant user receives the control over the target account

N/A

• The external system has access to the account with permissions to configure fees
• The fee distribution business rules are defined by the external systems

Use case flow

1. The external system configures the fee for the system (<<include>> FR0900)
2. Different users of the system performs operations, covered by the fee (<<include>> FR0901)
3. The Iroha network aggregates assets distribution according to the configured business rules
4. After predefined interval of time (attached to the block number) the Iroha network applies aggregated transactions to distribute fees
5. The external system eventually requests information about assets distribution by fee processing during selected period

• All fees are collected and distributed according to the business rules

• On step 4, the distribution mechanism can be triggered manually by the external system
• On step 5, the request can be done in keep-alive mode, using FR0208

N/A

Measurable characteristic of the response, which can be checked for understanding how the system satisfies the requirements

• Iroha 2 white-paper

• Iroha 2 white-paper

The Iroha peer restarts and restores the WSV in the storage using one of two modes:

• the fastInit mode, when all transactions are applied without the verification of the block storage consistency
• the strictInit mode, when all transactions and blocks are verified to have correct signature and follow the business rules