Decentralized crowdfunding for any projects
- A huge commission - up to 10%;
- Hard moderation - not any project can be published;
- the absence of a multilingual description of projects and great difficulties with the transfer of money, if the backer, for example, from China;
- the inability to return at least part of the money if the author of the project does not fulfill its obligations within the specified period.
I have solved all of the above problems partially or completely in my cryptocurrency, in which I have integrated the decentralized crowdfunding mechanism.
')
In 2 words about what I did
- The crowdfunding mechanism is embedded in the Dcoin protocol itself. Data about projects, backers, comments are copied to all nodes. No central servers are needed (with the exception of photohosting, such as imgur.com, for posting project descriptions).
- Commission 0.1% (goes to the nodes that sign the block).
- You can place absolutely any project, no one can block either the project or the wallet.
- You can collect funds while remaining anonymous.
- You can add descriptions in 10 languages.
- If you need rubles, then you can collect exactly rubles. If someone from China decided to invest 300 yuan in your project, they would need to go to the currency exchange (by the way, also decentralized and built into Dcoin) and exchange the yuan for rubles.
- If the project collects the indicated amount, then a new cryptocurrency is automatically issued. Coins of this currency are automatically distributed among all backers in proportion to the sums they have invested in the project. Project coins can be freely sold and bought on stock exchanges. The author of the project will have to sell his product for this currency. Thus, the currency goes out of circulation at the moment when the author of the project fulfilled its obligations. If the backer decided not to wait for the product to be ready, then he can sell the coins on the stock exchange to those who are ready to wait until the bitter end.
Pro Dcoin
Dcoin is a decentralized cryptocurrency, which has been functioning since April 2014. It has 2 types of accounts - anonymous and mining. If you buy coins on the exchange, you can use a simple anonymous account. Anonymous accounts and funds in their wallets can neither be blocked nor deleted.
Unlike Bitcoin, Dcoin has not one, but 66 types of different transactions , thanks to which Dcoin can exist in the form in which it is presented.
Example transaction structure:
| Field | Description | The size |
|---|---|---|
| TYPE | Transaction type | |
| TIME | Transaction time | |
| USER_ID | ID of the user who created the transaction | |
| CURRENCY_ID | Currency ID | |
| AMOUNT | The size of the promised amount | |
| VIDEO_TYPE | youtube, vimeo, youku, null | |
| VIDEO_URL_ID | ID from video hosting | |
| PAYMENT_SYSTEMS_IDS | Payment systems id | 1-24 bytes |
| SIGN | From 1 to 3 signatures (TYPE, TIME, USER_ID, CURRENCY_ID, AMOUNT, VIDEO_TYPE, VIDEO_URL_ID, PAYMENT_SYSTEMS_IDS) from USER_ID | 128 to 4096 bytes |
The header (TYPE, TIME, USER_ID) and SIGN are in all transactions, and all other fields change depending on the purpose of the transaction.
Block structure:
| Field | Description | The size |
|---|---|---|
| BLOCK_ID | Block sequence number | 4 bytes |
| TIME | The time when the block was created | 4 bytes |
| USER_ID | ID of the user who created the block | 5 bytes |
| LEVEL | The level at which the miner was at the time of block creation | 2 bytes |
| SIGN | Signature from (TYPE, BLOCK_ID, PREV_BLOCK_HASH, TIME, USER_ID, LEVEL, MRKL_ROOT) made with the node-key | from 128 bytes to 512 bytes |
| TRANSACTIONS | Transaction list | Up to 3Mb |
A more detailed description of the work of Dcoin can be found in the wiki .
Adding a new project
Starting a new project is very simple. You just need to fill in a few fields.
A few minutes after being sent to the DC network, when the transaction enters the block, your project will be available for funding, and it will be possible to send coins to it.
Transaction structure
| Field | Description |
|---|---|
| TYPE | Transaction type |
| TIME | Transaction time |
| USER_ID | ID of the user who created the transaction |
| CURRENCY_ID | Currency ID |
| AMOUNT | Desired amount |
| END_TIME | End of fundraising |
| LATITUDE | Latitude |
| LONGITUDE | Longitude |
| CATEGORY_ID | Category ID |
| PROJECT_CURRENCY_NAME | Name for new cryptocurrency |
| SIGN | From 1 to 3 signatures (TYPE, TIME, USER_ID, CURRENCY_ID, AMOUNT, END_TIME, LATITUDE, LONGITUDE, CATEGORY_ID, PROJECT_CURRENCY_NAME) from USER_ID |
Transaction example
(
[type] => 35
[time] => 1408470376
[user_id] => 1
[currency_id] => 72
[amount] => 1000
[end_time] => 1409075213
[latitude] => 39.94887
[longitude] => -75.15005
[category_id] => 4
[project_currency_name] => TEST003
[Sign] => 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
)
After processing such a transaction, an entry is created in the cf_projects table
Add description for project
You can attach up to 10 descriptions in different languages. Descriptions can be added only in the form of URL images. This is necessary in order to shift responsibility for the content of the content from unmoderated nodes to the hosting where the picture will be placed, as well as to save space in the database of the nodes.
Transaction structure
| Field | Description |
|---|---|
| TYPE | Transaction type |
| TIME | Transaction time |
| USER_ID | ID of the user who created the transaction |
| PROJECT_ID | Project ID |
| LANG_ID | Language ID |
| BLURB_IMG | Image for the catalog |
| HEAD_IMG | Cap image |
| DESCRIPTION_IMG | Project Description Picture |
| PICTURE | Main picture |
| VIDEO_TYPE | If there is video, then video_type |
| VIDEO_URL_ID | If there is video, then video_url_id |
| NEWS_IMG | Project news picture |
| LINKS | Links for picture descriptions in the format [["url1", x1, y1, x2, y2], ["url2", x1, y1, x2, y2], ...]. up to 512 characters. |
| HIDE | You can hide if you accidentally added a description in an unnecessary language |
| SIGN | From 1 to 3 signatures (TYPE, TIME, USER_ID, PROJECT_ID, LANG_ID, BLURB_IMG, HEAD_IMG, DESCRIPTION_IMG, PICTURE, VIDEO_TYPE, VIDEO_URL_ID, NEWS_IMG, LINKS, HIDE) from USER_ID |
Transaction example
(
[type] => 40
[time] => 1408470908
[user_id] => 1
[project_id] => 4
[lang_id] => 42
[blurb_img] => http://i.imgur.com/BBnBbC5.png
[head_img] => http://i.imgur.com/BBnBbC5.png
[description_img] => 0
[picture] => http://i.imgur.com/BBnBbC5.png
[video_type] => youtube
[video_url_id] => 0
[news_img] => 0
[links] => 0
[hide] => 0
[Sign] => 82010085c558dd411e816f589d57e48a02bf9231c9dcc55994568e0e00a7db3980c7005d91e88815e5e5a3dc5908a7c4f97c1f973f7ba576c86621f59b608e9d84ce9595710050a42a72e12fa78eb6dd12f8ff90f7004d8b8426a7cf714d7707899e8aafd9dc4534b94292fe849cce765ca975af88f2524874e22439716a59d1473baf115da4d67193320a33f36a442aa1c9711c3145c7499c207fbcc2846f9712bb0dc96c6c59708fd8d25e36a631213679a060a728473be8f23b8f8591bce50b64c67cca00d970fce93a714d2678119b1e67324e9b462986d11239337532a179a6f455f68d3a2e59df24f34590bc032b7c8cc5d633add4bef4c8c18efe7100a5a873
)
After processing such a transaction, an entry is created in the cf_projects_data table, or if an entry with the same language for the same project already exists, then the existing one is updated.
Sending coins to a crowdfunding project
In order to finance a project, you just need to click “Finance”, after which this form will open:
Transaction structure
| Field | Description |
|---|---|
| TYPE | Transaction type |
| TIME | Transaction time |
| USER_ID | ID of the user who created the transaction |
| PROJECT_ID | Project ID |
| AMOUNT | Amount |
| COMMISSION | Commission, which will go to the miner, who signed the block |
| COMMENT | Note encrypted by the project author’s public key |
| SIGN | From 1 to 3 signatures (TYPE, TIME, USER_ID, PROJECT_ID, AMOUNT, COMMISSION, COMMENT) from the user USER_ID |
Transaction example
([Type] => 48 [time] => 1408471786 [user_id] => 1 [project_id] => 4 [amount] => 100 [commission] => 0.1 [comment] => 4793010de6e65288fba7ba71e93883cafc0c724fb6306cc77b0525721b5e76883234997bcb4bda16e2568e5c1c30fb53fdb61999aa0c066189352d8ebc9d4dfb58d298d997cfdcf60c10d89815a4f620a68bbc690f95503e50e1913b3f82322df37895587413fde1b09c8acc4d746a145027b4753f180b073c31c8ab199f475d5c9c86841aaee506cb97bebe799e7497bf5765f848d9bfda3c58a44be9da4e86bb319d6580c5a35a8e49ec3a519bbfb53b33d590f691247929c2d489bcd8fa0d70c78c0b302edd39a474f116cfbf0d972ce0dee3999525d021161a6c5492c9a895eb01e764ee4fc1287ac41d3aea1b251108f362eb4984f01acf34ab0d202991 [sign] => 820100766b5e41a7fcc473912dfc74afdd7f47dbacbf0a8ebd6b3f552a3d58972cbd979c61e1942b59b1cfaa74b89a8bbc30849b7e9942e1fd16be2a48ccc0b2ffb1152bc737967ec3330b4225b4f195d7d7f8356c15ab72ccbaed9587445bacd45f367d7d20a34ed546b0d48dafe1cb4cf3a3d3187a50a52eafd09d874da67f7e2ccfd861a17b5ee91bbcf5cd92565faf5b2d25d249d0f6fe307d63cb883343eb9c9be4ff4c0ed2ca83ea3e5e8c54bf9d780d8 19e3f5ca2495c5aab4dff6c34bfa8d5bde60beeb84c6474305c968920a5526a6c563c96abdd4a67efb793637d009f0878bbec56e277b87ad4675098a4eb650c6910ab9734e4e4f4a4f4a2772639dbfc663cd6bf6bd60bd6bde60beeb84cfcfcfcfcfcdcdcbcdcbcbcbcd6bf6bfbcbfcb6c563cd6bfbcbfcbcc663cd6bfbcbcbcc663cd6bf6b34cb
After processing such a transaction, an entry is created in the cf_funding table, where the amount from the transaction is written, and the sender deducts this amount from the account.
If the end_time of the project <= time from the block, then the project is closed - in cf_projects in the close_block_id indicates the ID of the current block. Further 2 scenarios are possible:
1. The required amount is typed. In the cf_currency table, an entry is created with the name of the project currency. The project author is charged the collected amount. Backer's accrued project currency in proportion to the amount with which they financed the project.
2. The required amount is not recruited. All backers return the coins that they sent to this project.
Cancellation of financing
If you change your mind, you can return your coins until the project is completed. You just need to click cancel in the list of operations on your account.
Transaction structure
| Field | Description |
|---|---|
| TYPE | Transaction type |
| TIME | Transaction time |
| USER_ID | ID of the user who created the transaction |
| FUNDING_ID | ID from the cf_funding table |
| SIGN | From 1 to 3 signatures (TYPE, TIME, USER_ID, FUNDING_ID) from the user USER_ID |
Transaction example
(
[type] => 44
[time] => 1408472956
[user_id] => 1
[funding_id] => 40
[Sign] => 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
)
After processing such a transaction, del_block_id is specified in the cf_funding table for the specified ID. And the sender returns his coins.
Delete project
Until the fundraising is completed, you can delete your project. In this case, all funds will be returned to the backers.
Transaction structure
| Field | Description |
|---|---|
| TYPE | Transaction type |
| TIME | Transaction time |
| USER_ID | ID of the user who created the transaction |
| PROJECT_ID | Project ID |
| SIGN | From 1 to 3 signatures (TYPE, TIME, USER_ID, PROJECT_ID) from the user USER_ID |
Transaction example
(
[type] => 46
[time] => 1408473247
[user_id] => 1
[project_id] => 3
[Sign] => 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
)
After processing such a transaction in the cf_projects table for this project, del_block_id is indicated. And all the backers return their coins.
Category change for project
The project category can be changed at any time.
Transaction structure
| Field | Description |
|---|---|
| TYPE | Transaction type |
| TIME | Transaction time |
| USER_ID | ID of the user who created the transaction |
| PROJECT_ID | Project ID |
| CATEGORY_ID | Category ID |
| SIGN | From 1 to 3 signatures (TYPE, TIME, USER_ID, PROJECT_ID, CATEGORY_ID) from the user USER_ID |
Transaction example
(
[type] => 50
[time] => 1408475554
[user_id] => 1
[project_id] => 4
[category_id] => 13
[Sign] => 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
)
After processing such a transaction in the cf_projects table for this project, the category_id changes.
Comments
Comments can be written only by those who funded the project, or the author of the project. You can not delete comments.
Transaction structure
| Field | Description |
|---|---|
| TYPE | Transaction type |
| TIME | Transaction time |
| USER_ID | ID of the user who created the transaction |
| PROJECT_ID | Project ID |
| LANG_ID | Language ID |
| COMMENT | Comment |
| SIGN | From 1 to 3 signatures (TYPE, TIME, USER_ID, PROJECT_ID, LANG_ID, COMMENT) from the user USER_ID |
Transaction example
(
[type] => 47
[time] => 1408475862
[user_id] => 1
[project_id] => 4
[lang_id] => 42
[comment] => Test
[Sign] => 820100beb4a532f32b465b86d4ad54245e121d083a031e75da6c270af906ea55914bbc51ec6dcbfde872600b3d154d7f72dc70706a76ef153ec693dc2baf8f5938e393dc91fdc376cf5beada0bcf51aa4d409cf802b01738aae8c709b7734d68a84addd8bebd9079a4843a746fa209e350b656dee5038540099e809de6850907103d41561ef67757a02f68f8f19822ed7e33a4698cc45d17c2de02ff8530dba4a9a9b3866a518e3aeb31488321439d31a24e8d5fbd711a2f120d6e714e061427916c9f22a7553395772aec400c8305d156b30bdd7ed568d1826f005b56a2ad2ac6aed607a1c204e8c39b07513435cff0b9c56746d39017f5dd4fe20b7ac2c83cb39959
)
After processing such a transaction in the cf_comments table, a row is added with a new comment to the project.
That's all the transactions that are responsible for the functioning of Dcoin's crowdfunding.
The designer from me is useless, in order not to frighten people with his arts, I redraw the design of the pages with the projects of the kicksterter.
"All or nothing"
The author of the project can not pick up the coins if the project has not yet completed. It is necessary to combat fraud. Suppose 80% of the amount is accumulated, and suddenly one of the backers finds out that this is, for example, the resale of some goods from ebay in the third. He writes about this in the comments, and this comment is seen by all the old and new backers. Some of the old backers will cancel their payment, the project will not collect the required amount, and all coins will be returned.
Anonymity and security
With 3 keys associated with one user_id, you can safely and anonymously use Dcoin. You simply enter the address of any pool in the browser, enter the 1st key and get into your account. No trace of your stay will be left in the pool database. In this mode, you can transfer and receive coins, create and finance crowdfunding projects. If the admin pool integrates a script that will send your key to its server, then he can not do anything with it, because for any transaction on your behalf 2 more signatures will be required.
Source: https://habr.com/ru/post/234519/
All Articles