2018 - How the Rubyist use Blockchain

Transcript

1. How the Rubyist use Blockchain

2. WEB DEVELOPER GAME DEVELOPER 襟 儘 䓛⛳ @elct9620

3. None

4. I will talk about What is the Blockchain The examples

   use Ruby and Ethereum

5. What is the Blockchain

6. Linked List Cryptography Key-Value Data Store Distributed System

7. There is nothing new for us

8. None

9. Cryptocurrency

10. None

11. So, how the Blockchain works?

12. Chain =~ Linked List

13. The Chain Block #1 Block #2 Block #3 Pointer Pointer

14. Ok, I think you already learned it!

15. But, we have to limit anyone to write it!!!

16. 1. Proof of Work

17. 1. Prevent mass request from somebody 2. Other people can

    verify in short time Cryptography

18. Use cryptography to resolve question!

19. Cryptography Network Hash start with “000” Workers Define a Question

    Broadcast

20. Cryptography Workers 000abcdefaaabc… Network Try hash block Submit

21. Cryptography Network 000abcdefaaabc Block Created Verify result Accept

22. Wait! The same content will get the same hash result!

23. None

24. We add a random “Proof” string with block data

25. So, the worker should spend the time

26. And others can check it in short time

27. If we receive many correct answers…

28. Which one should accept?

29. 2. Byzantine Generals Problem

30. Distributed 1. Longest is right 2. 51% node think it

    is right

31. But, we didn’t discuss the algorithm in this talk

32. And last

33. How the Blockchain save data?

34. Merkle Tree

35. None

36. Very useful to update and verify data

37. But read will spend more time

38. Should I use pure ruby gem to operate blockchain?

39. It is hard to implement the same API in pure

    Ruby

40. Use the existed API to operate Blockchain.

41. But, you can implement blockchain in Ruby

42. Example Ethereum’s IPC Use Ruby to operate Ethereum

43. IPC =~ UnixSocket

44. None

45. How to get IPC and comminuted with it?

46. IPC 1. Ethereum Wallet 2. brew install geth 3. Compile

    from source code

47. “geth —light —testnet”

48. But I suggest using Ethereum Wallet

49. Because you can find IPC file very easy

50. But how to use UnixSocket to operate Ethereum?

51. JSON-RPC 2.0

52. None
53. None

54. And it always ends with a linefeed (\n)

55. None
56. None

57. Now, we can interact with Ethereum in Ruby

58. But the result has many hash value

59. What are the meaning and real data?

60. Ethereum Data 1. Call another API to get transaction value

    2. Read from “data” depend on ABI

61. If we just want to know transaction value

62. It always contains in API response

63. So, we talk about smart contract event

64. None

65. But we got the data in hex

66. None

67. It always returns the 32byte hex string for us

68. So, we need ABI to help us know the data

    type
69. None

70. Demo - Subscribe event and get data

71. Now, we know what can we do on the Ethereum

72. And last, is there has any useful resource?

73. Ruby Reference 1. digest-sha3 2. rlp 3. ruby-ethereum 4. Naivechain.rb

74. Conclusion

75. Build a blockchain in Ruby can help us learn it

76. And didn’t try to write a client in pure ruby

77. THANKS