github.com/hashgraph/hedera-sdk-go/v2@v2.48.0/examples/get_file_contents/main.go (about)

     1  package main
     2  
     3  import (
     4  	"fmt"
     5  	"os"
     6  
     7  	"github.com/hashgraph/hedera-sdk-go/v2"
     8  )
     9  
    10  func main() {
    11  	var client *hedera.Client
    12  	var err error
    13  
    14  	// Retrieving network type from environment variable HEDERA_NETWORK
    15  	client, err = hedera.ClientForName(os.Getenv("HEDERA_NETWORK"))
    16  	if err != nil {
    17  		panic(fmt.Sprintf("%v : error creating client", err))
    18  	}
    19  
    20  	// Retrieving operator ID from environment variable OPERATOR_ID
    21  	operatorAccountID, err := hedera.AccountIDFromString(os.Getenv("OPERATOR_ID"))
    22  	if err != nil {
    23  		panic(fmt.Sprintf("%v : error converting string to AccountID", err))
    24  	}
    25  
    26  	// Retrieving operator key from environment variable OPERATOR_KEY
    27  	operatorKey, err := hedera.PrivateKeyFromString(os.Getenv("OPERATOR_KEY"))
    28  	if err != nil {
    29  		panic(fmt.Sprintf("%v : error converting string to PrivateKey", err))
    30  	}
    31  
    32  	// Setting the client operator ID and key
    33  	client.SetOperator(operatorAccountID, operatorKey)
    34  
    35  	// Constructors exist for convenient files
    36  	//fileID := hedera.FileIDForAddressBook()
    37  	// fileID := hedera.FileIDForFeeSchedule()
    38  	fileID := hedera.FileIDForExchangeRate()
    39  
    40  	contents, err := hedera.NewFileContentsQuery().
    41  		// Set the file ID for whatever file you need
    42  		SetFileID(fileID).
    43  		Execute(client)
    44  
    45  	if err != nil {
    46  		panic(fmt.Sprintf("%v : error executing file contents query", err))
    47  	}
    48  
    49  	exchangeRate, err := hedera.ExchangeRateFromBytes(contents)
    50  	if err != nil {
    51  		panic(fmt.Sprintf("%v : error converting contents to exchange rate", err))
    52  	}
    53  
    54  	fmt.Printf("Contents for file %v :\n", fileID.String())
    55  	fmt.Print(exchangeRate.String())
    56  	fmt.Println()
    57  }