2018-Nov.md

November 2018

1. Creating Ethereum testnet

   • Info: https://medium.com/mercuryprotocol/how-to-create-your-own-private-ethereum-blockchain-dad6af82fc9f
   • Get geth from : https://geth.ethereum.org/downloads/
   • Create a genesis file: myGenesis.json with content:

     {
       "config": {
          "chainId": 1994,
          "homesteadBlock": 0,
          "eip155Block": 0,
          "eip158Block": 0,
          "byzantiumBlock": 0
       },
       "difficulty": "400",
       "gasLimit": "2000000",
       "alloc": {
          "7b684d27167d208c66584ece7f09d8bc8f86ffff": { 
              "balance": "100000000000000000000000" 
          },
          "ae13d41d66af28380c7af6d825ab557eb271ffff": { 
              "balance": "120000000000000000000000" 
          }
        }
     }
     

   • Initiate node: geth --datadir ./myDataDir init ./myGenesis.json
   • Delete generated DAG before starting node: rm ~\AppData\Ethash\full*
   • Start peer node: geth –datadir ./myDataDir --networkid 1114 console 2>> myEth.log
   • Read log: gc .\myEth.log | Select-String -Pattern "INFO" | Select-Object -Last 30

2. Golang templates (tags: golang html server template)

   • Templates are you know what they are pfff.
   • Parse whenever you parse new template text the previous one is overwritten (genius)
   • {{ define }} and {{ template }} don’t work with Parse
   • ParseFiles needs exact file location so forget that too.
   • Important links: https://gowebexamples.com/templates/

3. Http post request form-data vs json data body

   Form-data	Json-data
   Content-Type: application/x-www-form-urlencoded	Content-Type: application/json
   Example data: say=Hi&to=Mom	Example data: {“say”: “Hi”, “to”: “Mom”}
   Form-data is sent by browser in a post request	“json-data” is generally used in REST protocol

4. Go channels:

   • Create a channel: something := make(chan Struc)
   • Write only: chan<-
   • Read only: <-chan
   • Imp links: https://tour.golang.org/concurrency/2

5. Golang testing:

   • A test file ends with {something}_test.go
   • Execute with: go test
   • Call t.Parallel() to run that test in parallel to its siblings i.e. its children will still run sequentially
   • t.Run completes only when all its inner tests complete.

6. Lambda Calculus:

   • https://medium.com/@ayanonagon/the-y-combinator-no-not-that-one-7268d8d9c46
   • https://www.inf.fu-berlin.de/lehre/WS03/alpi/lambda.pdf

7. Adding formatted code text in windows (tag code formatted text notepad notepad++ plugin)

   • Do this by adding NppExport Plugin to notepad++
   • To add a plugin to notepad++:
   • Download the plugin dll file
   • Create a folder inside the plugin folder (C:\Program Files\Notepad++\plugins)

8. https://www.hanselman.com/blog/CompilingCToWASMWithMonoAndBlazorThenDebuggingNETSourceWithRemoteDebuggingInChromeDevTools.aspx

   • Tags: wasm c# csharp c sharp web development razor pages

9. Golang http server:

   • If writing a server look at this blog again: https://medium.com/statuscode/how-i-write-go-http-services-after-seven-years-37c208122831
   • Create a routes.go file for storing routes
   • Handlers are defined with returning a handler function http.HandlerFunc
   • The middlewares take a handler and return another handler.
   • The server struct contains all the global state that is needed. (database )