protocol-buffer

Final Objective:

membuat modeling data inventory komputer

Poin :

1. Mendefinisikan Skema
2. Multifile .proto
3. Field : Field rule, Field Types, Field Number
4. Advance field type : Enum, Nested

install compiler

brew install protobuf

go install google.golang.org/protobuf/cmd/protoc-gen-go

compile

//syntax compile
protoc -I=<source folder proto> --go_out=<source destination > --go_opt=paths=source_relative file.proto

//Example
cd /proto
protoc -I=. --go_out=../pb --go_opt=paths=source_relative todo.proto

1. mendefinisikan sebuah message (skema)

    syntax = "proto3";
    package pb;
    option go_package = "github.com/protocol-buffer/pb";

    // FORMAT 
    message <Name> {
        /**
         * field tag harus unik dan merupakan integer 
         * field tag yang dapat digunakan : 1 - 2^29-1
         * field tag yang tidak dapat digunakan : 19000 - 19999 
        */
        <Field-rule> <Field-Types> <name> = <field_tag>;
        ...
    }

    //Example 
    message CPU {
        string brand = 1;
        string name = 2;
        unit32 number_cores = 5;
        uint32 numbers_threads = 5;
        double min_ghz = 5;
        double max_ghz = 6;
    }

    message ... {
        ....
    }
     

2. Multifile .proto
   

   directory :
   

   /proto
     cpu.proto
     memory.proto
   

   from : cpu.Proto

   import "memory.proto";
   import "...";
   import "...";
   
   message ...  {
       Memory memory = 1;
   }
   

3. Field :

   1. **Field Types **
      

      1. Enum Type :FIELD NUMBER HARUS DIMULAI DARI 0
         

          message ... {
              enum <EnumName> {
                  DEFAULT = 0;
                  ....
              }
      
              EnumName fieldName = 1;
          }
      
              //example
              message Memory {
                  enum Unit {
                      UNKNOW = 0;
                      BIT = 1;
                      BYTE = 2;
                      KILOBYTE = 3;
                      MEGABYTE = 4;
                      GIGABYTE = 5;
                      TERABYTE = 6;
                  }
      
                  Unit unit = 1;
              }
      

      2. Composite
         

      message M1 {
          ...
      }
      
      message M2 {
           M2 composite = 1;
      }
      

      3. Date
         

         import "google/protobuf/timestamp.proto";
         
         message ... {
             ...
             google.protobuf.Timestamp updated_at = 1;
         }
         

   2. **Field Rule : array **
      

      1. Repeated: Array

         message M1 {
      
         }
      
         message M2 {
            repeated M2 composite = 1;
         }
      

      1. oneof : pilihan

          message Weight {
              oneof name {
                  double weight_kg = 1;
                  double weight_lb = 2;
              }
          }