george-hawkins

Pip basics with Python 3 on Ubuntu 16.04

It seems impossible to upgrade pip, even locally, without also breaking the system pip:

$ sudo apt install python3-pip
$ pip3 --version
pip 8.1.1 from /usr/lib/python3/dist-packages (python 3.5)
$ python3 -m pip install --user --upgrade pip

$ python3 -m pip --version

george-hawkins

Python notes

First notes from https://docs.python.org/3/tutorial/modules.html

Modules

Show search path for modules:

george-hawkins

Serialization and loops in Kotlin

First we found there were loops in the things we were trying to serialize and so you have to tell things that are going to walk these structures (like Jackson or even plain old equals) how to handle these to avoid recursing infinitely. Fair enough.

For Jackson you do this by telling it has to generate references like so:

@JsonIdentityInfo(generator=ObjectIdGenerators.UUIDGenerator::class, property="@id")
class Type ...

george-hawkins

Vagrant walkthru

Assuming you've already got VirtualBox and Vagrant already installed, let's create a Vagrant box on which to run some of these nodes and get its IP address:

$ cd
$ mkdir foo-vagrant
$ cd foo-vagrant
$ vagrant init bento/ubuntu-18.04

$ vagrant up

george-hawkins

import org.springframework.context.annotation.Configuration
import org.springframework.core.annotation.Order
import org.springframework.security.config.annotation.web.builders.HttpSecurity
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter

@Order(2)
@Configuration
class WebSecurityPublicConfiguration : WebSecurityConfigurerAdapter() {
    // ResourceServerConfiguration invokes OAuth2ResourceServerConfiguration.ResourceSecurityConfigurer.configure
    // which turns on authorization for all paths.

george-hawkins

package bookmarks

import org.springframework.beans.factory.annotation.Value
import org.springframework.context.annotation.Bean
import org.springframework.context.annotation.Configuration
import org.springframework.web.bind.annotation.RequestMethod
import springfox.documentation.builders.ApiInfoBuilder
import springfox.documentation.builders.PathSelectors
import springfox.documentation.builders.RequestHandlerSelectors
import springfox.documentation.builders.ResponseMessageBuilder

george-hawkins

package com.example

import org.junit.Test
import java.net.URI
import java.net.URL
import java.nio.file.FileSystem
import java.nio.file.FileSystemNotFoundException
import java.nio.file.FileSystems
import java.nio.file.Files
import java.nio.file.Paths

george-hawkins

Note: this page is heavily chopped down from multiple earlier sources, so it doesn't hang together very well at this stage. It's now just a collection of facts and thoughts about Corda notaries.

How is a Corda notary different to a centralized DB?

Distributed DBs (both SQL and NoSQL) that guarantee eventual consistency have been around for a long time outside the world of distributed ledger.

How is a Corda notary really different to a centralized DB?

Note: whether behind the scenes a notary or centralized DB is implemented as a single system or as a distributed cluster is largely irrelevant to the primary parties involved (in a Corda environment that's the nodes).

george-hawkins

if [[ -n $SSH_CLIENT || -n $SSH_TTY ]]
then
    PS1_HOST='\h'
else
    PS1_HOST=localhost
fi

# Usually people use raw escape sequences for colors but you can lookup these sequences with tput.
BOLD=$(tput bold)
GREEN=$(tput setaf 2)

george-hawkins

diff --git a/gradle-plugins/cordformation/src/noderunner/kotlin/net/corda/plugins/NodeRunner.kt b/gradle-plugins/cordformation/src/noderunner/kotlin/net/corda/plugins/NodeRunner.kt
index 83462c2..0f3d67b 100644
--- a/gradle-plugins/cordformation/src/noderunner/kotlin/net/corda/plugins/NodeRunner.kt
+++ b/gradle-plugins/cordformation/src/noderunner/kotlin/net/corda/plugins/NodeRunner.kt
@@ -50,14 +50,20 @@ private abstract class JarType(private val jarName: String) {
         }
         val debugPort = debugPortAlloc.next()
         println("Starting $jarName in $dir on debug port $debugPort")
-        val process = (if (headless) ::HeadlessJavaCommand else ::TerminalWindowJavaCommand)(jarName, dir, debugPort, javaArgs, jvmArgs).start()
+        val appArgs = javaArgs + (if (headless) headlessArgs else headedArgs)