![eos_developer_tutorials.png](https://cdn.steemitimages.com/DQmVLoih7CyiYdiDMD9VnTy3GpMASDgEhokBEuTMaZHphtt/eos_developer_tutorials.png) # EOSIO v1.2.0 Smart Contract Tutorial by: Gunnar Pope on 8/16/18 Check it out on my [github](https://github.com/gunnarpope/eosio/blob/master/smart_contracts/smart_contracts_tutorial.md). This set of dev notes I recorded while walking thorugh the developers notes posted on the [eosio developer's portal](https://developers.eos.io/eosio-cpp/docs/introduction-to-smart-contracts). This is just the basics of these eosio contracts but I will customize them more in later posts. I'm using a Ubuntu 18.04 system and run two terminal windows - 1 for `nodeos` to interact with the blockchain and 1 for `cleos` commands to interact with nodeos and sign actions with my wallet. * First off, open a terminal and start `nodeos` to start a block producing node. ``` $ nodeos -e -p eosio --plugin eosio::chain_api_plugin --plugin eosio::history_api_plugin ..... 2018-08-16T13:54:26.501 thread-0 producer_plugin.cpp:1295 produce_block ] Produced block 00003179b22e6343... #12665 @ 2018-08-16T13:54:26.500 signed by eosio [trxs: 0, lib: 12664, confirmed: 0] 2018-08-16T13:54:27.001 thread-0 producer_plugin.cpp:1295 produce_block ] Produced block 0000317a5dfd11ad... #12666 @ 2018-08-16T13:54:27.000 signed by eosio [trxs: 0, lib: 12665, confirmed: 0] 2018-08-16T13:54:27.500 thread-0 producer_plugin.cpp:1295 produce_block ] Produced block 0000317b139445d7... #12667 @ 2018-08-16T13:54:27.500 signed by eosio [trxs: 0, lib: 12666, confirmed: 0] ``` * Open a new terminal window. Unlock your wallet, check if it is unlocked, and if you don't have the eosio account key (EOS6MRy...) imported to your wallet, add it. ``` ~/eos $ cleos wallet unlock password: ~/eos $ cleos wallet list Wallets: [ "default *" ] ~/eos $ cleos wallet import --private-key 5KQwrPbwdL6PhXujxW37FSSQZ1JiwsST4cqQzDeyXtP79zkvFD3 imported private key for: EOS6MRyAjQq8ud7hVNYcfnVPJqcVpscN5So8BhtHuGYqET5GDW5CV ``` * Use the account ${eosio} to upload the eosio.bios contract with @active permissions. This account could be any EOSIO account name. ``` ~/eos $ cleos set contract eosio build/contracts/eosio.bios -p eosio@active Reading WASM from build/contracts/eosio.bios/eosio.bios.wasm... Publishing contract... executed transaction: e21617635c447eee18e908b3283e46b59648837a776ddf9ea0602d98d1a6932a 3720 bytes 1842 us # eosio <= eosio::setcode {"account":"eosio","vmtype":0,"vmversion":0,"code":"0061736d0100000001621260037f7e7f0060057f7e7e7e7e... # eosio <= eosio::setabi {"account":"eosio","abi":"0e656f73696f3a3a6162692f312e30050c6163636f756e745f6e616d65046e616d650f7065... 2018-08-16T12:09:19.514 thread-0 main.cpp:455 print_result warning: transaction executed locally, but may not be confirmed by the network yet ``` * Now that the bios contact is built, create some keys for a new account ``` ~/eos $ cleos create key --to-console Private key: 5JHasbXY3zCNaMhLb1MMhdDd72EJDFSywYDaoxwa7p1TwyJEUVT Public key: EOS6QvdEGw67NLdJe15jCQkTNFJDZvj9oNvKheKw2fbob3g6rer8K ~/eos $ cleos wallet import private key: imported private key for: EOS6QvdEGw67NLdJe15jCQkTNFJDZvj9oNvKheKw2fbob3g6rer8K ``` * Build two new accounts named ${user} and ${tester} ``` ~/eos $ cleos create account eosio user EOS6QvdEGw67NLdJe15jCQkTNFJDZvj9oNvKheKw2fbob3g6rer8K EOS6QvdEGw67NLdJe15jCQkTNFJDZvj9oNvKheKw2fbob3g6rer8K executed transaction: 701e0f4bdd4ee70d33ac57f00809af1b97dee654a07e6e4d90535f4facc7cacf 200 bytes 928 us # eosio <= eosio::newaccount {"creator":"eosio","name":"user","owner":{"threshold":1,"keys":[{"key":"EOS6QvdEGw67NLdJe15jCQkTNFJD... 2018-08-16T12:20:17.432 thread-0 main.cpp:455 print_result warning: transaction executed locally, but may not be confirmed by the network yet ~/eos $ cleos create account eosio tester EOS6QvdEGw67NLdJe15jCQkTNFJDZvj9oNvKheKw2fbob3g6rer8K EOS6QvdEGw67NLdJe15jCQkTNFJDZvj9oNvKheKw2fbob3g6rer8K executed transaction: 559be9ac016df1507e2b6959862f6c01a4c567c47f820d8fa56c0767d543d18c 200 bytes 250 us # eosio <= eosio::newaccount {"creator":"eosio","name":"tester","owner":{"threshold":1,"keys":[{"key":"EOS6QvdEGw67NLdJe15jCQkTNF... 2018-08-16T12:20:35.203 thread-0 main.cpp:455 print_result warning: transaction executed locally, but may not be confirmed by the network yet ``` * View the accounts created. ``` ~/eos $ cleos get accounts EOS6QvdEGw67NLdJe15jCQkTNFJDZvj9oNvKheKw2fbob3g6rer8K { "account_names": [ "tester", "user" ] } ``` * Now that the eosio.bios contract has been uploaded, let's create an account called ${eosio.token} ``` ~/eos $ cleos create account eosio eosio.token EOS6QvdEGw67NLdJe15jCQkTNFJDZvj9oNvKheKw2fbob3g6rer8K EOS6QvdEGw67NLdJe15jCQkTNFJDZvj9oNvKheKw2fbob3g6rer8K executed transaction: 41503f1b9ac0f8abf77b1a2bf9af784a45c46c7f0fc0840f83fa0c59a673291f 200 bytes 271 us # eosio <= eosio::newaccount {"creator":"eosio","name":"eosio.token","owner":{"threshold":1,"keys":[{"key":"EOS6QvdEGw67NLdJe15jC... 2018-08-16T12:30:08.737 thread-0 main.cpp:455 print_result warning: transaction executed locally, but may not be confirmed by the network yet ``` * Now load the eosio.token contract into the eosio.token account ``` ~/eos $ cleos set contract eosio.token build/contracts/eosio.token -p eosio.token@active Reading WASM from build/contracts/eosio.token/eosio.token.wasm... Publishing contract... executed transaction: 1781f4c1968e7f60e9e979aaa90356c3209a137d0f48aad1b391c96d329f43ad 8104 bytes 3028 us # eosio <= eosio::setcode {"account":"eosio.token","vmtype":0,"vmversion":0,"code":"0061736d01000000017e1560037f7e7f0060057f7e... # eosio <= eosio::setabi {"account":"eosio.token","abi":"0e656f73696f3a3a6162692f312e30010c6163636f756e745f6e616d65046e616d65... 2018-08-16T12:32:27.549 thread-0 main.cpp:455 print_result warning: transaction executed locally, but may not be confirmed by the network yet ``` * You could use any account to upload this contract. Example: make an account named gunnar.token and upload the same contract: ``` ~/eos $ cleos create account eosio gunnar.token EOS6QvdEGw67NLdJe15jCQkTNFJDZvj9oNvKheKw2fbob3g6rer8K EOS6QvdEGw67NLdJe15jCQkTNFJDZvj9oNvKheKw2fbob3g6rer8K executed transaction: 21d6c1b5e31f16751d446a10fdb96d926cd1f4966871ceb908ea191c49b21eec 200 bytes 273 us # eosio <= eosio::newaccount {"creator":"eosio","name":"gunnar.token","owner":{"threshold":1,"keys":[{"key":"EOS6QvdEGw67NLdJe15j... 2018-08-16T12:43:16.781 thread-0 main.cpp:455 print_result warning: transaction executed locally, but may not be confirmed by the network yet ~/eos $ cleos set contract gunnar.token build/contracts/eosio.token -p gunnar.token@active Reading WASM from build/contracts/eosio.token/eosio.token.wasm... Publishing contract... executed transaction: 8da1cceca9d4b4acadd43de216d61b83d39c7b5f87615fe955236318321229a7 8104 bytes 1266 us # eosio <= eosio::setcode {"account":"gunnar.token","vmtype":0,"vmversion":0,"code":"0061736d01000000017e1560037f7e7f0060057f7... # eosio <= eosio::setabi {"account":"gunnar.token","abi":"0e656f73696f3a3a6162692f312e30010c6163636f756e745f6e616d65046e616d6... 2018-08-16T12:43:36.867 thread-0 main.cpp:455 print_result warning: transaction executed locally, but may not be confirmed by the network yet ``` * Now, create a token using this contract. The gunnar.token contract will create 1 Million 'SKI' tokens ``` ~/eos $ cleos push action gunnar.token create '["eosio", "1000000.000 SKI"]' -p gunnar.token@active executed transaction: 39895f61b1cf62269a52d3f4f1343643af4039ea786d3ee021075d76a9b8167e 120 bytes 361 us # gunnar.token <= gunnar.token::create {"issuer":"eosio","maximum_supply":"1000000.000 SKI"} 2018-08-16T12:50:17.436 thread-0 main.cpp:455 print_result warning: transaction executed locally, but may not be confirmed by the network yet ``` * Or, you can create a token using the positional arguments. To begin, use cleos to get the gunnar.token action arguments from the .abi file: ``` ~/eos $ cleos get abi gunnar.token { "version": "eosio::abi/1.0", "types": [{ "new_type_name": "account_name", "type": "name" } ], "structs": [{ "name": "transfer", "base": "", "fields": [{ "name": "from", "type": "account_name" },{ "name": "to", "type": "account_name" },{ "name": "quantity", "type": "asset" },{ "name": "memo", "type": "string" } ] },{ "name": "create", "base": "", "fields": [{ "name": "issuer", "type": "account_name" },{ "name": "maximum_supply", "type": "asset" } ] },{ "name": "issue", "base": "", "fields": [{ "name": "to", "type": "account_name" },{ "name": "quantity", "type": "asset" },{ "name": "memo", "type": "string" } ] },{ "name": "account", "base": "", "fields": [{ "name": "balance", "type": "asset" } ] },{ "name": "currency_stats", "base": "", "fields": [{ "name": "supply", "type": "asset" },{ "name": "max_supply", "type": "asset" },{ "name": "issuer", "type": "account_name" } ] } ], "actions": [{ "name": "transfer", "type": "transfer", "ricardian_contract": "" },{ "name": "issue", "type": "issue", "ricardian_contract": "" },{ "name": "create", "type": "create", "ricardian_contract": "" } ], "tables": [{ "name": "accounts", "index_type": "i64", "key_names": [ "currency" ], "key_types": [ "uint64" ], "type": "account" },{ "name": "stat", "index_type": "i64", "key_names": [ "currency" ], "key_types": [ "uint64" ], "type": "currency_stats" } ], "ricardian_clauses": [], "error_messages": [], "abi_extensions": [] } ``` * Look at the .abi file and see that there is an action called "create" that has a "structs" of type "create". Look into the "structs" section to find what arguments it takes. We can see that the "create" struct has two fields: "issuer", "maximum_supply". ``` "actions": [ ..... { "name": "create", "type": "create", "ricardian_contract": "" } ], "structs": [ ..... { "name": "create", "base": "", "fields": [{ "name": "issuer", "type": "account_name" },{ "name": "maximum_supply", "type": "asset" } ] } ``` Therefore, we can pass these arguments in a json format to the cleos push action command using `'{"issuer":"eosio", "maximum_supply":"1000000.0000 GCP"}'` ``` ~/eos $ cleos push action gunnar.token create '{"issuer":"eosio", "maximum_supply":"1000000.0000 GCP"}' -p gunnar.token@active executed transaction: 2ada0aa1c34e61fa4fcbe7c6becf11b37305176f5d3eac462b022363db81af94 120 bytes 350 us # gunnar.token <= gunnar.token::create {"issuer":"eosio","maximum_supply":"1000000.0000 GCP"} 2018-08-16T12:55:00.418 thread-0 main.cpp:455 print_result warning: transaction executed locally, but may not be confirmed by the network yet ``` * Issue tokens to account ${user}. ``` ~/eos $ cleos push action gunnar.token issue '[ "user", "100.0000 GCP", "memo"]' -p eosio@active executed transaction: 6ff6aaf959a05e631b947c3b29f1a081180c63e0d5653354d9a396295482db8e 128 bytes 1002 us # gunnar.token <= gunnar.token::issue {"to":"user","quantity":"100.0000 GCP","memo":"memo"} # gunnar.token <= gunnar.token::transfer {"from":"eosio","to":"user","quantity":"100.0000 GCP","memo":"memo"} # eosio <= gunnar.token::transfer {"from":"eosio","to":"user","quantity":"100.0000 GCP","memo":"memo"} # user <= gunnar.token::transfer {"from":"eosio","to":"user","quantity":"100.0000 GCP","memo":"memo"} 2018-08-16T13:09:59.939 thread-0 main.cpp:455 print_result warning: transaction executed locally, but may not be confirmed by the network yet ``` * Incorporate a memo into your transction stating "payment for services". ``` ~/eos $ cleos push action gunnar.token issue '[ "user", "100.0000 GCP", "payment for services"]' -p eosio@active executed transaction: 2fba791c246b6d6929a0bbc799bc12fc5367904d2f37a634d3c170a4193106fb 144 bytes 1713 us # gunnar.token <= gunnar.token::issue {"to":"user","quantity":"100.0000 GCP","memo":"payment for services"} # gunnar.token <= gunnar.token::transfer {"from":"eosio","to":"user","quantity":"100.0000 GCP","memo":"payment for services"} # eosio <= gunnar.token::transfer {"from":"eosio","to":"user","quantity":"100.0000 GCP","memo":"payment for services"} # user <= gunnar.token::transfer {"from":"eosio","to":"user","quantity":"100.0000 GCP","memo":"payment for services"} 2018-08-16T13:12:06.906 thread-0 main.cpp:455 print_result warning: transaction executed locally, but may not be confirmed by the network yet ``` That's all for now! We'll do another tutorial tonight or tomorrow and keep the eos development going. Please let me know if you like these tutorials and how I can improve them. ## Next step: Finish the multi sig tutorials from the eosio github page. https://developers.eos.io/eosio-cpp/docs/token-tutorial Thanks and I hope you enjoy! Please upvote and resteem if you like it.. @eosgo @eos @dan @jd3 @jarib

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