proxmox/docs/08-monitoring/BLOCKSCOUT_VERIFICATION_GUIDE.md

Blockscout Contract Verification Guide - ChainID 138

Last Updated: 2026-01-31
Document Version: 1.0
Status: Active Documentation

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Purpose: Guide for verifying smart contracts on ChainID 138 using Blockscout
Block Explorer: https://explorer.d-bis.org

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Overview

ChainID 138 uses Blockscout (self-hosted) as its block explorer. This guide covers how to verify smart contracts deployed on ChainID 138 using Foundry's verification tools.

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Prerequisites

1. Foundry installed and configured
2. Deployed contracts on ChainID 138
3. Access to contract source code and constructor arguments
4. Blockscout instance accessible at https://explorer.d-bis.org

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Blockscout Configuration

Block Explorer Information

• URL: https://explorer.d-bis.org
• API Endpoint: https://explorer.d-bis.org/api
• Type: Self-hosted Blockscout
• Chain ID: 138
• API Key: Not required (self-hosted instance)

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Verification Methods

Method 1: Using Foundry Script with Verification

When deploying contracts with Foundry, add Blockscout verification flags:

forge script script/YourDeploymentScript.s.sol:YourScript \
  --rpc-url https://rpc-core.d-bis.org \
  --private-key $PRIVATE_KEY \
  --broadcast \
  --verify \
  --verifier blockscout \
  --verifier-url https://explorer.d-bis.org/api \
  -vvvv

Method 2: Manual Verification with forge verify-contract

After deployment, verify contracts manually:

forge verify-contract \
  <CONTRACT_ADDRESS> \
  <CONTRACT_NAME> \
  --chain-id 138 \
  --rpc-url https://rpc-core.d-bis.org \
  --verifier blockscout \
  --verifier-url https://explorer.d-bis.org/api \
  --constructor-args $(cast abi-encode "constructor(<ARGS>)" <ARG1> <ARG2> ...) \
  --compiler-version <VERSION>

Method 3: Using Foundry.toml Configuration

Add Blockscout configuration to foundry.toml:

[etherscan]
chain138 = { 
  url = "https://explorer.d-bis.org/api",
  verifier = "blockscout"
}

Then use:

forge verify-contract \
  <CONTRACT_ADDRESS> \
  <CONTRACT_NAME> \
  --chain chain138 \
  --rpc-url https://rpc-core.d-bis.org

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Verification Examples

Example 1: Simple Contract (No Constructor Arguments)

forge verify-contract \
  0x1234567890123456789012345678901234567890 \
  SimpleContract \
  --chain-id 138 \
  --rpc-url https://rpc-core.d-bis.org \
  --verifier blockscout \
  --verifier-url https://explorer.d-bis.org/api \
  --compiler-version 0.8.20

Example 2: Contract with Constructor Arguments

# First, encode constructor arguments
CONSTRUCTOR_ARGS=$(cast abi-encode "constructor(address,uint256)" \
  0x1111111111111111111111111111111111111111 \
  1000000000000000000)

# Then verify
forge verify-contract \
  0x1234567890123456789012345678901234567890 \
  ComplexContract \
  --chain-id 138 \
  --rpc-url https://rpc-core.d-bis.org \
  --verifier blockscout \
  --verifier-url https://explorer.d-bis.org/api \
  --constructor-args "$CONSTRUCTOR_ARGS" \
  --compiler-version 0.8.20

Example 3: Verify with Libraries

If your contract uses libraries, specify them:

forge verify-contract \
  <CONTRACT_ADDRESS> \
  <CONTRACT_NAME> \
  --chain-id 138 \
  --rpc-url https://rpc-core.d-bis.org \
  --verifier blockscout \
  --verifier-url https://explorer.d-bis.org/api \
  --libraries <LIBRARY_NAME>:<LIBRARY_ADDRESS> \
  --compiler-version <VERSION>

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When proxy returns "Invalid JSON"

If you run ./scripts/verify/run-contract-verification-with-proxy.sh and get Invalid JSON, result=None, Blockscout may have returned a non-JSON response.

Note: Using --verifier-url https://explorer.d-bis.org/api directly with Forge (no proxy) fails with Params 'module' and 'action' are required — Blockscout's Etherscan-compatible API expects these as query parameters, which the forge-verification-proxy adds. So verification must use either (1) the proxy from a host that can reach Blockscout, or (2) manual UI below.

From a host where explorer.d-bis.org is reachable, you can try the proxy again, or verify manually. If you have a custom client that sends module=contract&action=verifysourcecode, you can verify directly:

cd smom-dbis-138
RPC="${RPC_URL_138:-https://rpc-core.d-bis.org}"
VERIFIER="https://explorer.d-bis.org/api"

# CCIPSender
forge verify-contract 0x105F8A15b819948a89153505762444Ee9f324684 \
  contracts/ccip/CCIPSender.sol:CCIPSender \
  --chain-id 138 --rpc-url "$RPC" --verifier blockscout --verifier-url "$VERIFIER" --flatten

# Oracle Proxy
forge verify-contract 0x3304b747e565a97ec8ac220b0b6a1f6ffdb837e6 \
  contracts/oracle/Proxy.sol:Proxy \
  --chain-id 138 --rpc-url "$RPC" --verifier blockscout --verifier-url "$VERIFIER" --flatten

# CCIPWETH9Bridge
forge verify-contract 0xcacfd227A040002e49e2e01626363071324f820a \
  contracts/ccip/CCIPWETH9Bridge.sol:CCIPWETH9Bridge \
  --chain-id 138 --rpc-url "$RPC" --verifier blockscout --verifier-url "$VERIFIER" --flatten

# CCIPWETH10Bridge
forge verify-contract 0xe0E93247376aa097dB308B92e6Ba36bA015535D0 \
  contracts/ccip/CCIPWETH10Bridge.sol:CCIPWETH10Bridge \
  --chain-id 138 --rpc-url "$RPC" --verifier blockscout --verifier-url "$VERIFIER" --flatten

Or run the batch script with the proxy pointing at the public explorer URL (from a host that can reach it): FORGE_VERIFIER_URL=https://explorer.d-bis.org/api ./scripts/verify-contracts-blockscout.sh (from repo root, after cd smom-dbis-138 as needed for paths). See also OPERATOR_OPTIONAL_CHECKLIST § Blockscout.

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Troubleshooting

Issue: Verification Fails with "Contract Not Found"

Solution:

• Ensure the contract is deployed and confirmed on ChainID 138
• Verify the contract address is correct
• Check that the RPC endpoint is accessible

Issue: "Invalid Source Code"

Solution:

• Ensure compiler version matches the deployment compiler version
• Verify all source files are accessible
• Check that constructor arguments are correctly encoded

Issue: "Already Verified"

Solution:

• The contract is already verified on Blockscout
• Check the contract on the explorer: https://explorer.d-bis.org/address/<CONTRACT_ADDRESS>

Issue: Blockscout API Timeout

Solution:

• Check if Blockscout instance is running and accessible
• Verify network connectivity to https://explorer.d-bis.org
• Try again after a few moments (Blockscout may be indexing)

Issue: Verification returns HTML or 502

Symptom: Proxy or Forge reports "Invalid JSON", "Blockscout returned HTML", or 502 Bad Gateway.

Causes: Blockscout (VMID 5000) may be down, DB not migrated, or thin pool full. The proxy converts non-JSON responses into a clear error message.

Solutions:

1. From LAN: Ensure Blockscout is reachable: curl -s -o /dev/null -w "%{http_code}" http://192.168.11.140:4000/api?module=stats&action=eth_price (expect 200 or 404, not 502).
2. Fix Blockscout: Follow BLOCKSCOUT_FIX_RUNBOOK.md (SSL/migrations, thin pool, start stack).
3. Verify via UI: Use Verify & Publish in the explorer (see section below) when the site is up; no proxy needed.

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Manual Verification via Blockscout UI

If automated verification fails, you can verify contracts manually through the Blockscout web interface:

1. Navigate to the contract address: https://explorer.d-bis.org/address/<CONTRACT_ADDRESS>
2. Click on "Verify & Publish" tab
3. Select verification method:
   • Via Standard JSON Input (recommended)
   • Via Sourcify
   • Via Multi-file
4. Upload contract source code and metadata
5. Provide constructor arguments (if any)
6. Submit for verification

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Verification Best Practices

1. Verify Immediately After Deployment: Verify contracts right after deployment while deployment details are fresh
2. Use Standard JSON Input: Most reliable method for complex contracts
3. Document Constructor Arguments: Keep a record of constructor arguments used during deployment
4. Test Verification Locally: Test your verification command before deploying to production
5. Keep Source Code Organized: Maintain clean source code structure for easier verification

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Related Documentation

• Block Explorer: https://explorer.d-bis.org
• RPC Endpoint: https://rpc-core.d-bis.org
• API Keys Documentation: See docs/CROSS_CHAIN_BRIDGE_ADDRESSES.md
• Contract Deployment Guide: See docs/CONTRACT_DEPLOYMENT_GUIDE.md

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Quick Reference

Blockscout API Endpoints

• API Base URL: https://explorer.d-bis.org/api
• Contract Verification: POST /api/v2/smart-contracts/<ADDRESS>/verification
• Contract Info: GET /api/v2/smart-contracts/<ADDRESS>

Common Verification Flags

--verifier blockscout                    # Use Blockscout verifier
--verifier-url https://explorer.d-bis.org/api  # Blockscout API URL
--chain-id 138                           # Chain ID 138
--compiler-version 0.8.20                # Solidity compiler version
--constructor-args <ENCODED_ARGS>        # Encoded constructor arguments
--libraries <LIB>:<ADDR>                 # Library addresses

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Last Updated: 2026-02-23
Status: ✅ Ready for use with ChainID 138