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* CORDA-594 - SIMM Demo doc update For V1 write a series of JSON / curl commands a user can follow to run the demo * Review Comments * Updated the rationale behind as to why SIMM was introduced. * typo
435 lines
22 KiB
ReStructuredText
435 lines
22 KiB
ReStructuredText
Running the demos
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=================
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.. contents::
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The `Corda repository <https://github.com/corda/corda>`_ contains a number of demo programs demonstrating
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Corda's functionality:
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1. The :ref:`trader-demo`, which shows a delivery-vs-payment atomic swap of commercial paper for cash
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2. The :ref:`irs-demo`, which shows two nodes establishing an interest rate swap and performing fixings with a
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rates oracle
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3. The :ref:`attachment-demo`, which demonstrates uploading attachments to nodes
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4. The :ref:`notary-demo`, which shows three different types of notaries and a single node getting multiple transactions
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notarised
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5. The :ref:`bank-of-corda-demo`, which shows a node acting as an issuer of assets (the Bank of Corda) while remote client
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applications request issuance of some cash on behalf of a node called Big Corporation
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If any of the demos don't work, please raise an issue on `GitHub <https://github.com/corda/corda/issues>`_.
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.. note:: If you are running the demos from the command line in Linux (but not macOS), you may have to install xterm.
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.. note:: If you would like to see flow activity on the nodes type in the node terminal ``flow watch``.
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.. _trader-demo:
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Trader demo
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-----------
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This demo brings up four nodes: Bank A, Bank B, Bank Of Corda, and a notary/network map node that they all use. Bank A will
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be the buyer, and requests some cash from the Bank of Corda in order to acquire commercial paper from Bank B, the seller.
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To run from the command line in Unix:
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1. Run ``./gradlew samples:trader-demo:deployNodes`` to create a set of configs and installs under ``samples/trader-demo/build/nodes``
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2. Run ``./samples/trader-demo/build/nodes/runnodes`` to open up four new terminals with the four nodes
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3. Run ``./gradlew samples:trader-demo:runBank`` to instruct the bank node to issue cash and commercial paper to the buyer and seller nodes respectively.
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4. Run ``./gradlew samples:trader-demo:runSeller`` to trigger the transaction. If you entered ``flow watch``
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you can see flows running on both sides of transaction. Additionally you should see final trade information displayed
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to your terminal.
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To run from the command line in Windows:
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1. Run ``gradlew samples:trader-demo:deployNodes`` to create a set of configs and installs under ``samples\trader-demo\build\nodes``
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2. Run ``samples\trader-demo\build\nodes\runnodes`` to open up four new terminals with the four nodes
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3. Run ``gradlew samples:trader-demo:runBank`` to instruct the buyer node to request issuance of some cash from the Bank of Corda node
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4. Run ``gradlew samples:trader-demo:runSeller`` to trigger the transaction. If you entered ``flow watch``
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you can see flows running on both sides of transaction. Additionally you should see final trade information displayed
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to your terminal.
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.. _irs-demo:
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IRS demo
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--------
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This demo brings up three nodes: Bank A, Bank B and a node that simultaneously runs a notary, a network map and an interest rates
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oracle. The two banks agree on an interest rate swap, and then do regular fixings of the deal as the time
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on a simulated clock passes.
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To run from the command line in Unix:
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1. Run ``./gradlew samples:irs-demo:deployNodes`` to install configs and a command line tool under ``samples/irs-demo/build``
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2. Run ``./gradlew samples:irs-demo:installDist``
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3. Move to the ``samples/irs-demo/build`` directory
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4. Run ``./nodes/runnodes`` to open up three new terminals with the three nodes (you may have to install xterm).
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To run from the command line in Windows:
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1. Run ``gradlew.bat samples:irs-demo:deployNodes`` to install configs and a command line tool under ``samples\irs-demo\build``
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2. Run ``gradlew.bat samples:irs-demo:installDist``
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3. Run ``cd samples\irs-demo\build`` to change current working directory
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4. Run ``nodes\runnodes`` to open up several 6 terminals, 2 for each node. First terminal is a web-server associated with every node and second one is Corda interactive shell for the node.
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This demo also has a web app. To use this, run nodes and then navigate to
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http://localhost:10007/web/irsdemo and http://localhost:10010/web/irsdemo to see each node's view of the ledger.
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To use the web app, click the "Create Deal" button, fill in the form, then click the "Submit" button. You can then
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use the time controls at the top left of the home page to run the fixings. Click any individual trade in the blotter to view it.
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.. note:: The IRS web UI currently has a bug when changing the clock time where it may show no numbers or apply fixings inconsistently.
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The issues will be addressed in a future milestone release. Meanwhile, you can take a look at a simpler oracle example https://github.com/corda/oracle-example
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.. _attachment-demo:
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Attachment demo
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---------------
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This demo brings up three nodes, and sends a transaction containing an attachment from one to the other.
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To run from the command line in Unix:
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1. Run ``./gradlew samples:attachment-demo:deployNodes`` to create a set of configs and installs under ``samples/attachment-demo/build/nodes``
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2. Run ``./samples/attachment-demo/build/nodes/runnodes`` to open up three new terminal tabs/windows with the three nodes and webserver for BankB
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3. Run ``./gradlew samples:attachment-demo:runRecipient``, which will block waiting for a trade to start
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4. Run ``./gradlew samples:attachment-demo:runSender`` in another terminal window to send the attachment. Now look at the other windows to
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see the output of the demo
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To run from the command line in Windows:
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1. Run ``gradlew samples:attachment-demo:deployNodes`` to create a set of configs and installs under ``samples\attachment-demo\build\nodes``
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2. Run ``samples\attachment-demo\build\nodes\runnodes`` to open up three new terminal tabs/windows with the three nodes and webserver for BankB
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3. Run ``gradlew samples:attachment-demo:runRecipient``, which will block waiting for a trade to start
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4. Run ``gradlew samples:attachment-demo:runSender`` in another terminal window to send the attachment. Now look at the other windows to
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see the output of the demo
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.. _notary-demo:
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Notary demo
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-----------
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This demo shows a party getting transactions notarised by either a single-node or a distributed notary service.
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All versions of the demo start two counterparty nodes.
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One of the counterparties will generate transactions that transfer a self-issued asset to the other party and submit them for notarisation.
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The `Raft <https://raft.github.io/>`_ version of the demo will start three distributed notary nodes.
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The `BFT SMaRt <https://bft-smart.github.io/library/>`_ version of the demo will start four distributed notary nodes.
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The output will display a list of notarised transaction IDs and corresponding signer public keys. In the Raft distributed notary,
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every node in the cluster can service client requests, and one signature is sufficient to satisfy the notary composite key requirement.
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In the BFT SMaRt distributed notary, three signatures are required.
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You will notice that successive transactions get signed by different members of the cluster (usually allocated in a random order).
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To run the Raft version of the demo from the command line in Unix:
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1. Run ``./gradlew samples:notary-demo:deployNodes``, which will create all three types of notaries' node directories
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with configs under ``samples/notary-demo/build/nodes/nodesRaft`` (``nodesBFT`` and ``nodesSingle`` for BFT and
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Single notaries).
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2. Run ``./samples/notary-demo/build/nodes/nodesRaft/runnodes``, which will start the nodes in separate terminal windows/tabs.
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Wait until a "Node started up and registered in ..." message appears on each of the terminals
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3. Run ``./gradlew samples:notary-demo:notarise`` to make a call to the "Party" node to initiate notarisation requests
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In a few seconds you will see a message "Notarised 10 transactions" with a list of transaction ids and the signer public keys
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To run from the command line in Windows:
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1. Run ``gradlew samples:notary-demo:deployNodes``, which will create all three types of notaries' node directories
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with configs under ``samples/notary-demo/build/nodes/nodesRaft`` (``nodesBFT`` and ``nodesSingle`` for BFT and
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Single notaries).
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2. Run ``samples\notary-demo\build\nodes\nodesRaft\runnodes``, which will start the nodes in separate terminal windows/tabs.
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Wait until a "Node started up and registered in ..." message appears on each of the terminals
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3. Run ``gradlew samples:notary-demo:notarise`` to make a call to the "Party" node to initiate notarisation requests
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In a few seconds you will see a message "Notarised 10 transactions" with a list of transaction ids and the signer public keys
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To run the BFT SMaRt notary demo, use ``nodesBFT`` instead of ``nodesRaft`` in the path (you will see messages from notary nodes
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trying to communicate each other sometime with connection errors, that's normal). For a single notary node, use ``nodesSingle``.
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Notary nodes store consumed states in a replicated commit log, which is backed by a H2 database on each node.
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You can ascertain that the commit log is synchronised across the cluster by accessing and comparing each of the nodes' backing stores
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by using the H2 web console:
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- Firstly, download `H2 web console <http://www.h2database.com/html/download.html>`_ (download the "platform-independent zip"),
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and start it using a script in the extracted folder: ``h2/bin/h2.sh`` (or ``h2\bin\h2`` for Windows)
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- If you are uncertain as to which version of h2 to install or if you have connectivity issues, refer to ``build.gradle``
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located in the ``node`` directory and locate the compile step for ``com.h2database``. Use a client of the same
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major version - even if still in beta.
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- The H2 web console should start up in a web browser tab. To connect we first need to obtain a JDBC connection string.
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Each node outputs its connection string in the terminal window as it starts up. In a terminal window where a node is running,
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look for the following string:
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``Database connection url is : jdbc:h2:tcp://10.18.0.150:56736/node``
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You can use the string on the right to connect to the h2 database: just paste it into the `JDBC URL` field and click *Connect*.
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You will be presented with a web application that enumerates all the available tables and provides an interface for you to query them using SQL
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- The committed states are stored in the ``NOTARY_COMMITTED_STATES`` table. Note that the raw data is not human-readable,
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but we're only interested in the row count for this demo
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.. _bank-of-corda-demo:
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Bank Of Corda demo
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------------------
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This demo brings up three nodes: a notary, a node acting as the Bank of Corda that accepts requests for issuance of some asset
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and a node acting as Big Corporation which requests issuance of an asset (cash in this example).
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Upon receipt of a request the Bank of Corda node self-issues the asset and then transfers ownership to the requester
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after successful notarisation and recording of the issue transaction on the ledger.
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.. note:: The Bank of Corda is somewhat like a "Bitcoin faucet" that dispenses free bitcoins to developers for
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testing and experimentation purposes.
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To run from the command line in Unix:
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1. Run ``./gradlew samples:bank-of-corda-demo:deployNodes`` to create a set of configs and installs under ``samples/bank-of-corda-demo/build/nodes``
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2. Run ``./samples/bank-of-corda-demo/build/nodes/runnodes`` to open up three new terminal tabs/windows with the three nodes
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3. Run ``./gradlew samples:bank-of-corda-demo:runRPCCashIssue`` to trigger a cash issuance request
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4. Run ``./gradlew samples:bank-of-corda-demo:runWebCashIssue`` to trigger another cash issuance request.
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Now look at your terminal tab/window to see the output of the demo
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To run from the command line in Windows:
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1. Run ``gradlew samples:bank-of-corda-demo:deployNodes`` to create a set of configs and installs under ``samples\bank-of-corda-demo\build\nodes``
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2. Run ``samples\bank-of-corda-demo\build\nodes\runnodes`` to open up three new terminal tabs/windows with the three nodes
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3. Run ``gradlew samples:bank-of-corda-demo:runRPCCashIssue`` to trigger a cash issuance request
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4. Run ``gradlew samples:bank-of-corda-demo:runWebCashIssue`` to trigger another cash issuance request.
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Now look at the your terminal tab/window to see the output of the demo
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.. note:: To verify that the Bank of Corda node is alive and running, navigate to the following URL:
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http://localhost:10007/api/bank/date
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In the window you run the command you should see (in case of Web, RPC is simmilar):
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- Requesting Cash via Web ...
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- Successfully processed Cash Issue request
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If you want to see flow activity enter in node's shell ``flow watch``. It will display all state machines
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running currently on the node.
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Launch the Explorer application to visualize the issuance and transfer of cash for each node:
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``./gradlew tools:explorer:run`` (on Unix) or ``gradlew tools:explorer:run`` (on Windows)
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Using the following login details:
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- For the Bank of Corda node: localhost / port 10006 / username bankUser / password test
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- For the Big Corporation node: localhost / port 10009 / username bigCorpUser / password test
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See https://docs.corda.net/node-explorer.html for further details on usage.
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.. _simm-demo:
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SIMM and Portfolio Demo - aka the Initial Margin Agreement Demo
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---------------------------------------------------------------
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Background and SIMM Introduction
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********************************
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This app is a demonstration of how Corda can be used for the real world requirement of initial margin calculation and
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agreement; featuring the integration of complex and industry proven third party libraries into Corda nodes.
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SIMM is an acronym for "Standard Initial Margin Model". It is effectively the calculation of a "margin" that is paid
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by one party to another when they agree a trade on certain types of transaction.
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The SIMM was introduced to standardise the calculation of how much margin counterparties charge each other on their
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bilateral transactions. Before SIMM, each counterparty computed margins according to its own model and it was made it very
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difficult to agree the exact margin with the counterparty that faces the same trade on the other side.
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To enact this, in September 2016, the ISDA committee - with full backing from various governing bodies -
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`issued a ruling on what is known as the ISDA SIMM ™ model <http://www2.isda.org/news/isda-simm-deployed-today-new-industry-standard-for-calculating-initial-margin-widely-adopted-by-market-participants>`_,
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a way of fairly and consistently calculating this margin. Any parties wishing to trade a financial product that is
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covered under this ruling would, independently, use this model and calculate their margin payment requirement,
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agree it with their trading counterparty and then pay (or receive, depending on the results of this calculation)
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this amount. In the case of disagreement that is not resolved in a timely fashion, this payment would increase
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and so therefore it is in the parties' interest to reach agreement in as short as time frame as possible.
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To be more accurate, the SIMM calculation is not performed on just one trade - it is calculated on an aggregate of
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intermediary values (which in this model are sensitivities to risk factors) from a portfolio of trades; therefore
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the input to a SIMM is actually this data, not the individual trades themselves.
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Also note that implementations of the SIMM are actually protected and subject to license restrictions by ISDA
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(this is due to the model itself being protected). We were fortunate enough to technically partner with
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`OpenGamma <http://www.opengamma.com>`_ who allowed us to demonstrate the SIMM process using their proprietary model.
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In the source code released, we have replaced their analytics engine with very simple stub functions that allow
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the process to run without actually calculating correct values, and can easily be swapped out in place for their real libraries.
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What happens in the demo (notionally)
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*************************************
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Preliminaries
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- Ensure that there are a number of live trades with another party based on financial products that are covered under the
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ISDA SIMM agreement (if none, then use the demo to enter some simple trades as described below).
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Initial Margin Agreement Process
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- Agree that one will be performing the margining calculation against a portfolio of trades with another party, and agree the trades in that portfolio. In practice, one node will start the flow but it does not matter which node does.
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- Individually (at the node level), identify the data (static, reference etc) one will need in order to be able to calculate the metrics on those trades
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- Confirm with the other counterparty the dataset from the above set
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- Calculate any intermediary steps and values needed for the margin calculation (ie sensitivities to risk factors)
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- Agree on the results of these steps
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- Calculate the initial margin
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- Agree on the calculation of the above with the other party
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- In practice, pay (or receive) this margin (omitted for the sake of complexity for this example)
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Demo execution (step by step)
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*****************************
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**Setting up the Corda infrastructure**
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To run from the command line in Unix:
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1. Deploy the nodes using ``./gradlew samples:simm-valuation-demo:deployNodes``
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2. Run the nodes using ``./samples/simm-valuation-demo/build/nodes/runnodes``
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To run from the command line in Windows:
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1. Deploy the nodes using ``gradlew samples:simm-valuation-demo:deployNodes``
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2. Run the nodes using ``samples\simm-valuation-demo\build\nodes\runnodes``
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**Getting Bank A's details**
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From the command line run
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.. sourcecode:: bash
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curl http://localhost:10005/api/simmvaluationdemo/whoami
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The response should be something like
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.. sourcecode:: none
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{
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"self" : {
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"id" : "8Kqd4oWdx4KQGHGQW3FwXHQpjiv7cHaSsaAWMwRrK25bBJj792Z4rag7EtA",
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"text" : "C=GB,L=London,O=Bank A"
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},
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"counterparties" : [
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{
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"id" : "8Kqd4oWdx4KQGHGL1DzULumUmZyyokeSGJDY1n5M6neUfAj2sjbf65wYwQM",
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"text" : "C=JP,L=Tokyo,O=Bank C"
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},
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{
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"id" : "8Kqd4oWdx4KQGHGTBm34eCM2nrpcWKeM1ZG3DUYat3JTFUQTwB3Lv2WbPM8",
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"text" : "C=US,L=New York,O=Bank B"
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}
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]
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}
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Now, if we ask the same question of Bank C we will see that it's id matches the id for Bank C as a counter
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party to Bank A and Bank A will appear as a counter party
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.. sourcecode:: bash
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curl -i -H "Content-Type: application/json" -X GET http://localhost:10011/api/simmvaluationdemo/whoami
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**Creating a trade with Bank C**
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In what follows, we assume we are Bank A (which is listening on port 10005)
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Notice the id field in the output of the ``whoami`` command. We are going to use the id assocatied
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with Bank C, one of our counter parties, to create a trade. The general command for this is:
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.. sourcecode:: bash
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curl -i -H "Content-Type: application/json" -X PUT -d <<<JSON representation of the trade>>> http://localhost:10005/api/simmvaluationdemo/<<<counter party id>>>/trades
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where the representation of the trade is
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.. sourcecode:: none
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{
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"id" : "trade1",
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"description" : "desc",
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"tradeDate" : [ 2016, 6, 6 ],
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"convention" : "EUR_FIXED_1Y_EURIBOR_3M",
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"startDate" : [ 2016, 6, 6 ],
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"endDate" : [ 2020, 1, 2 ],
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"buySell" : "BUY",
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"notional" : "1000",
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"fixedRate" : "0.1"
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}
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Continuing our example, the specific command we would run is
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.. sourcecode:: bash
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curl -i -H "Content-Type: application/json" \
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-X PUT \
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-d '{"id":"trade1","description" : "desc","tradeDate" : [ 2016, 6, 6 ], "convention" : "EUR_FIXED_1Y_EURIBOR_3M", "startDate" : [ 2016, 6, 6 ], "endDate" : [ 2020, 1, 2 ], "buySell" : "BUY", "notional" : "1000", "fixedRate" : "0.1"}' \
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http://localhost:10005/api/simmvaluationdemo/8Kqd4oWdx4KQGHGL1DzULumUmZyyokeSGJDY1n5M6neUfAj2sjbf65wYwQM/trades
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With an expected response of
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.. sourcecode:: none
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HTTP/1.1 202 Accepted
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Date: Thu, 28 Sep 2017 17:19:39 GMT
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Content-Type: text/plain
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Access-Control-Allow-Origin: *
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Content-Length: 2
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Server: Jetty(9.3.9.v20160517)
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**Verifying trade completion**
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With the trade completed and stored by both parties, the complete list of trades with our couterparty can be seen with the following command
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.. sourcecode:: bash
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curl -X GET http://localhost:10005/api/simmvaluationdemo/<<<counter party id>>>/trades
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The command for our example, using Bank A, would thus be
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.. sourcecode:: bash
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curl -X GET http://localhost:10005/api/simmvaluationdemo/8Kqd4oWdx4KQGHGL1DzULumUmZyyokeSGJDY1n5M6neUfAj2sjbf65wYwQM/trades
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whilst a specific trade can be seen with
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.. sourcecode:: bash
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curl -X GET http://localhost:10005/api/simmvaluationdemo/<<<counter party id>>>/trades/<<<trade id>>>
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If we look at the trade we created above, we assigned it the id "trade1", the complete command in this case would be
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.. sourcecode:: bash
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curl -X GET http://localhost:10005/api/simmvaluationdemo/8Kqd4oWdx4KQGHGL1DzULumUmZyyokeSGJDY1n5M6neUfAj2sjbf65wYwQM/trades/trade1
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**Generating a valuation**
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.. sourcecode:: bash
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curl -i -H "Content-Type: application/json" \
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-X POST \
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-d <<<JSON representation>>>
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http://localhost:10005/api/simmvaluationdemo/<<<counter party id>>>/portfolio/valuations/calculate
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Again, the specific command to continue our example would be
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.. sourcecode:: bash
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curl -i -H "Content-Type: application/json" \
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-X POST \
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-d '{"valuationDate":[2016,6,6]}' \
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http://localhost:10005/api/simmvaluationdemo/8Kqd4oWdx4KQGHGL1DzLumUmZyyokeSGJDY1n5M6neUfAj2sjbf65wYwQM/portfolio/valuations/calculate
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**Viewing a valuation**
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In the same way we can ask for specific instances of trades with a counter party, we can request details of valuations
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.. sourcecode:: bash
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curl -i -H "Content-Type: application/json" -X GET http://localhost:10005/api/simmvaluationdemo/<<<counter party id>>>/portfolio/valuations
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The specific command for out Bank A example is
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.. sourcecode:: bash
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curl -i -H "Content-Type: application/json" \
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-X GET http://localhost:10005/api/simmvaluationdemo/8Kqd4oWdx4KQGHGL1DzULumUmZyyokeSGJDY1n5M6neUfAj2sjbf65YwQM/portfolio/valuations
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