From be472b61e776ea44a872b54742af8664660aa27c Mon Sep 17 00:00:00 2001 From: fragosti Date: Tue, 7 Aug 2018 13:22:11 -0700 Subject: Add markdown section --- packages/sra-api/src/md/introduction.md | 180 ++++++++++++++++++++++++++++++++ 1 file changed, 180 insertions(+) create mode 100644 packages/sra-api/src/md/introduction.md (limited to 'packages/sra-api/src/md/introduction.md') diff --git a/packages/sra-api/src/md/introduction.md b/packages/sra-api/src/md/introduction.md new file mode 100644 index 000000000..c3aa4d4da --- /dev/null +++ b/packages/sra-api/src/md/introduction.md @@ -0,0 +1,180 @@ +# Pagination + +Requests that return potentially large collections should respond to the **?page** and **?per_page** parameters. For example: + +``` +curl https://api.example-relayer.com/v2/token_pairs?page=3&per_page=20 +``` + +Page numbering should be 1-indexed, not 0-indexed. If a query provides an unreasonable (ie. too high) **per_page** value, the response can return a validation error as specified in the [errors section](#errors). If the query specifies a **page** that does not exist (ie. there are not enough **records**), the response should just return an empty **records** array. + +All endpoints that are paginated should return a **total**, **page**, **perPage** and a **records** value in the top level of the collection. The value of **total** should be the total number of records for a given query, whereas **records** should be an array representing the response to the query for that page. **page** and **perPage**, are the same values that were specified in the request. See the note in [miscellaneous](#misc) about formatting `snake_case` vs. `lowerCamelCase`. + +These requests include the [`asset_pairs`](#get-v2-asset-pairs), [`orders`](#get-v2-orders), and [`orderbook`](#get-v2-orderbook) endpoints. + +# Network Id +All requests should be able to specify a **?networkId** query param for all supported networks. For example: +``` +curl https://api.example-relayer.com/v2/token_pairs?networkId=1 +``` +If the query param is not provided, it should default to **1** (mainnet). + +Networks and their Ids: + +| Network Id | Network Name | +| ---------- | ------------ | +| 1 | Mainnet | +| 42 | Kovan | +| 3 | Ropsten | +| 4 | Rinkeby | + + If a certain network is not supported, the response should **400** as specified in the [error response](#error-response) section. For example: + +``` +{ + "code": 100, + "reason": "Validation failed", + "validationErrors": [ + { + "field": "networkId", + "code": 1006, + "reason": "Network id 42 is not supported", + } + ] +} +``` + +# Link Header + +A [Link Header](https://tools.ietf.org/html/rfc5988) can be included in a response to provide clients with more context about paging +For example: + +``` +Link: ; rel="next", +; rel="last" +``` + +This `Link` response header contains one or more Hypermedia link relations. + +The possible `rel` values are: + +| Name | Description | +| ----- | ------------------------------------------------------------- | +| next | The link relation for the immediate next page of results. | +| last | The link relation for the last page of results. | +| first | The link relation for the first page of results. | +| prev | The link relation for the immediate previous page of results. | + +# Rate Limits + +Rate limit guidance for clients can be optionally returned in the response headers: + +| Header Name | Description | +| --------------------- | ---------------------------------------------------------------------------- | +| X-RateLimit-Limit | The maximum number of requests you're permitted to make per hour. | +| X-RateLimit-Remaining | The number of requests remaining in the current rate limit window. | +| X-RateLimit-Reset | The time at which the current rate limit window resets in UTC epoch seconds. | + +For example: + +``` +curl -i https://api.example-relayer.com/v2/token_pairs +HTTP/1.1 200 OK +Date: Mon, 20 Oct 2017 12:30:06 GMT +Status: 200 OK +X-RateLimit-Limit: 60 +X-RateLimit-Remaining: 56 +X-RateLimit-Reset: 1372700873 +``` +When a rate limit is exceeded, a status of **429 Too Many Requests** should be returned. + +# Errors + +Unless the spec defines otherwise, errors to bad requests should respond with HTTP 4xx or status codes. + +## Common error codes + +| Code | Reason | +| ---- | --------------------------------------- | +| 400 | Bad Request – Invalid request format | +| 404 | Not found | +| 429 | Too many requests - Rate limit exceeded | +| 500 | Internal Server Error | +| 501 | Not Implemented | + +## Error reporting format +For all **400** responses, see the [error response schema](https://github.com/0xProject/0x-monorepo/blob/development/packages/json-schemas/schemas/relayer_api_error_response_schema.ts#L1). + +``` +{ + "code": 101, + "reason": "Validation failed", + "validationErrors": [ + { + "field": "maker", + "code": 1002, + "reason": "Invalid address" + } + ] +} +``` + +General error codes: + +``` +100 - Validation Failed +101 - Malformed JSON +102 - Order submission disabled +103 - Throttled +``` + +Validation error codes: + +``` +1000 - Required field +1001 - Incorrect format +1002 - Invalid address +1003 - Address not supported +1004 - Value out of range +1005 - Invalid signature or hash +1006 - Unsupported option +``` + +# Asset Data Encoding + +As we now support multiple [token transfer proxies](https://github.com/0xProject/0x-protocol-specification/blob/master/v2/v2-specification.md#assetproxy), the identifier of which proxy to use for the token transfer must be encoded, along with the token information. Each proxy in 0x v2 has a unique identifier. If you're using 0x.js there will be helper methods for this [encoding](https://0xproject.com/docs/0x.js#zeroEx-encodeERC20AssetData) and [decoding](https://0xproject.com/docs/0x.js#zeroEx-decodeAssetProxyId). + +The identifier for the Proxy uses a similar scheme to [ABI function selectors](https://github.com/ethereum/wiki/wiki/Ethereum-Contract-ABI#function-selector). +``` +// ERC20 Proxy ID 0xf47261b0 +bytes4(keccak256("ERC20Token(address)")) +// ERC721 Proxy ID 0x08e937fa +bytes4(keccak256("ERC721Token(address,uint256)")) +``` + +Asset data is encoded using [ABI encoding](https://solidity.readthedocs.io/en/develop/abi-spec.html). + +For example, encoding the ERC20 token contract (address: 0x1dc4c1cefef38a777b15aa20260a54e584b16c48) using the ERC20 Transfer Proxy (id: 0xf47261b0) would be: +``` +0xf47261b00000000000000000000000001dc4c1cefef38a777b15aa20260a54e584b16c48 +``` + +Encoding the ERC721 token contract (address: `0x371b13d97f4bf77d724e78c16b7dc74099f40e84`), token id (id: `99`, which hex encoded is `0x63`) and the ERC721 Transfer Proxy (id: 0x08e937fa) would be: +``` +0x08e937fa000000000000000000000000371b13d97f4bf77d724e78c16b7dc74099f40e840000000000000000000000000000000000000000000000000000000000000063 +``` + +For more information see [the Asset Proxy](https://github.com/0xProject/0x-protocol-specification/blob/master/v2/v2-specification.md#erc20proxy) section of the v2 spec and the [Ethereum ABI Spec](https://solidity.readthedocs.io/en/develop/abi-spec.html). + +# Meta Data in Order Responses + +In v2 of the standard relayer API we added the `metaData` field. It is meant to provide a standard place for relayers to put optional, custom or non-standard fields that may of interest to the consumer of the API. + +A good example of such a field is `remainingTakerAssetAmount`, which is a convenience field that communicates how much of a 0x order is potentially left to be filled. Unlike the other fields in a 0x order, it is not guaranteed to be correct as it is derived from whatever mechanism the implementer (ie. the relayer) is using. While convenient for prototyping and low stakes situations, we recommend validating the value of the field by checking the state of the blockchain yourself, such as by using [Order Watcher](https://0xproject.com/wiki#0x-OrderWatcher). + +# Misc. + +* All requests and responses should be of **application/json** content type +* All token amounts are sent in amounts of the smallest level of precision (base units). (e.g if a token has 18 decimal places, selling 1 token would show up as selling `'1000000000000000000'` units by this API). +* All addresses are sent as lower-case (non-checksummed) Ethereum addresses with the `0x` prefix. +* All URL query parameters are to be written in `snake_case` and all queries and responses specified in JSON should use `lowerCamelCase`. -- cgit v1.2.3 From e6c91493f2f99dea2e7e0ef6aa1365552f100fa4 Mon Sep 17 00:00:00 2001 From: fragosti Date: Tue, 7 Aug 2018 16:26:25 -0700 Subject: token_pairs -> asset_pairs --- packages/sra-api/src/md/introduction.md | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'packages/sra-api/src/md/introduction.md') diff --git a/packages/sra-api/src/md/introduction.md b/packages/sra-api/src/md/introduction.md index c3aa4d4da..4d0679f9e 100644 --- a/packages/sra-api/src/md/introduction.md +++ b/packages/sra-api/src/md/introduction.md @@ -3,7 +3,7 @@ Requests that return potentially large collections should respond to the **?page** and **?per_page** parameters. For example: ``` -curl https://api.example-relayer.com/v2/token_pairs?page=3&per_page=20 +curl https://api.example-relayer.com/v2/asset_pairs?page=3&per_page=20 ``` Page numbering should be 1-indexed, not 0-indexed. If a query provides an unreasonable (ie. too high) **per_page** value, the response can return a validation error as specified in the [errors section](#errors). If the query specifies a **page** that does not exist (ie. there are not enough **records**), the response should just return an empty **records** array. @@ -15,7 +15,7 @@ These requests include the [`asset_pairs`](#get-v2-asset-pairs), [`orders`](#get # Network Id All requests should be able to specify a **?networkId** query param for all supported networks. For example: ``` -curl https://api.example-relayer.com/v2/token_pairs?networkId=1 +curl https://api.example-relayer.com/v2/asset_pairs?networkId=1 ``` If the query param is not provided, it should default to **1** (mainnet). @@ -50,7 +50,7 @@ A [Link Header](https://tools.ietf.org/html/rfc5988) can be included in a respon For example: ``` -Link: ; rel="next", +Link: ; rel="next", ; rel="last" ``` @@ -78,7 +78,7 @@ Rate limit guidance for clients can be optionally returned in the response heade For example: ``` -curl -i https://api.example-relayer.com/v2/token_pairs +curl -i https://api.example-relayer.com/v2/asset_pairs HTTP/1.1 200 OK Date: Mon, 20 Oct 2017 12:30:06 GMT Status: 200 OK -- cgit v1.2.3 From 083d42c8f778e8a88f21f179e3ec271f8a762268 Mon Sep 17 00:00:00 2001 From: fragosti Date: Wed, 8 Aug 2018 14:36:38 -0700 Subject: Fix links in markdown --- packages/sra-api/src/md/introduction.md | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) (limited to 'packages/sra-api/src/md/introduction.md') diff --git a/packages/sra-api/src/md/introduction.md b/packages/sra-api/src/md/introduction.md index 4d0679f9e..f0dfb04b1 100644 --- a/packages/sra-api/src/md/introduction.md +++ b/packages/sra-api/src/md/introduction.md @@ -2,20 +2,20 @@ Requests that return potentially large collections should respond to the **?page** and **?per_page** parameters. For example: -``` -curl https://api.example-relayer.com/v2/asset_pairs?page=3&per_page=20 +```bash +$ curl https://api.example-relayer.com/v2/asset_pairs?page=3&per_page=20 ``` -Page numbering should be 1-indexed, not 0-indexed. If a query provides an unreasonable (ie. too high) **per_page** value, the response can return a validation error as specified in the [errors section](#errors). If the query specifies a **page** that does not exist (ie. there are not enough **records**), the response should just return an empty **records** array. +Page numbering should be 1-indexed, not 0-indexed. If a query provides an unreasonable (ie. too high) **per_page** value, the response can return a validation error as specified in the [errors section](#section/Errors). If the query specifies a **page** that does not exist (ie. there are not enough **records**), the response should just return an empty **records** array. -All endpoints that are paginated should return a **total**, **page**, **perPage** and a **records** value in the top level of the collection. The value of **total** should be the total number of records for a given query, whereas **records** should be an array representing the response to the query for that page. **page** and **perPage**, are the same values that were specified in the request. See the note in [miscellaneous](#misc) about formatting `snake_case` vs. `lowerCamelCase`. +All endpoints that are paginated should return a **total**, **page**, **perPage** and a **records** value in the top level of the collection. The value of **total** should be the total number of records for a given query, whereas **records** should be an array representing the response to the query for that page. **page** and **perPage**, are the same values that were specified in the request. See the note in [miscellaneous](#section/Misc.) about formatting `snake_case` vs. `lowerCamelCase`. -These requests include the [`asset_pairs`](#get-v2-asset-pairs), [`orders`](#get-v2-orders), and [`orderbook`](#get-v2-orderbook) endpoints. +These requests include the [`asset_pairs`](#operation/getAssetPairs), [`orders`](#operation/getOrders), and [`orderbook`](#operation/getOrderbook) endpoints. # Network Id All requests should be able to specify a **?networkId** query param for all supported networks. For example: -``` -curl https://api.example-relayer.com/v2/asset_pairs?networkId=1 +```bash +$ curl https://api.example-relayer.com/v2/asset_pairs?networkId=1 ``` If the query param is not provided, it should default to **1** (mainnet). @@ -28,7 +28,7 @@ Networks and their Ids: | 3 | Ropsten | | 4 | Rinkeby | - If a certain network is not supported, the response should **400** as specified in the [error response](#error-response) section. For example: + If a certain network is not supported, the response should **400** as specified in the [error response](#section/Errors) section. For example: ``` { -- cgit v1.2.3 From 9e3fe7092bd0fe1b9d00e8d619ad9b4ce90c3bf1 Mon Sep 17 00:00:00 2001 From: fragosti Date: Wed, 8 Aug 2018 14:47:43 -0700 Subject: Add section about json-schemas and sra report --- packages/sra-api/src/md/introduction.md | 34 +++++++++++++++++++++++++++++---- 1 file changed, 30 insertions(+), 4 deletions(-) (limited to 'packages/sra-api/src/md/introduction.md') diff --git a/packages/sra-api/src/md/introduction.md b/packages/sra-api/src/md/introduction.md index f0dfb04b1..76a144225 100644 --- a/packages/sra-api/src/md/introduction.md +++ b/packages/sra-api/src/md/introduction.md @@ -1,3 +1,29 @@ +# Testing + +Use the [sra-report](https://github.com/0xProject/0x-monorepo/tree/development/packages/sra-report) command line tool to test your API for SRA compliance. + +# Schemas + +The [JSON schemas](http://json-schema.org/) for the API payloads and responses can be found in [@0xproject/json-schemas](https://github.com/0xProject/0x.js/tree/development/packages/json-schemas). Examples of each payload and response can be found in the library's [test suite](https://github.com/0xProject/0x.js/blob/development/packages/json-schemas/test/schema_test.ts#L1). + +```bash +npm install @0xproject/json-schemas --save +``` + +You can easily validate your API's payloads and responses using the [@0xproject/json-schemas](https://github.com/0xProject/0x.js/tree/development/packages/json-schemas) package: + +```js +import {SchemaValidator, ValidatorResult, schemas} from '@0xproject/json-schemas'; + +const {relayerApiTokenPairsResponseSchema} = schemas; +const validator = new SchemaValidator(); + +const tokenPairsResponse = { + ... +}; +const validatorResult: ValidatorResult = validator.validate(tokenPairsResponse, relayerApiTokenPairsResponseSchema); +``` + # Pagination Requests that return potentially large collections should respond to the **?page** and **?per_page** parameters. For example: @@ -6,11 +32,11 @@ Requests that return potentially large collections should respond to the **?page $ curl https://api.example-relayer.com/v2/asset_pairs?page=3&per_page=20 ``` -Page numbering should be 1-indexed, not 0-indexed. If a query provides an unreasonable (ie. too high) **per_page** value, the response can return a validation error as specified in the [errors section](#section/Errors). If the query specifies a **page** that does not exist (ie. there are not enough **records**), the response should just return an empty **records** array. +Page numbering should be 1-indexed, not 0-indexed. If a query provides an unreasonable (ie. too high) `per_page` value, the response can return a validation error as specified in the [errors section](#section/Errors). If the query specifies a `page` that does not exist (ie. there are not enough `records`), the response should just return an empty `records` array. -All endpoints that are paginated should return a **total**, **page**, **perPage** and a **records** value in the top level of the collection. The value of **total** should be the total number of records for a given query, whereas **records** should be an array representing the response to the query for that page. **page** and **perPage**, are the same values that were specified in the request. See the note in [miscellaneous](#section/Misc.) about formatting `snake_case` vs. `lowerCamelCase`. +All endpoints that are paginated should return a `total`, `page`, `perPage` and a `records` value in the top level of the collection. The value of `total` should be the total number of records for a given query, whereas `records` should be an array representing the response to the query for that page. `page` and `perPage`, are the same values that were specified in the request. See the note in [miscellaneous](#section/Misc.) about formatting `snake_case` vs. `lowerCamelCase`. -These requests include the [`asset_pairs`](#operation/getAssetPairs), [`orders`](#operation/getOrders), and [`orderbook`](#operation/getOrderbook) endpoints. +These requests include the [`/v2/asset_pairs`](#operation/getAssetPairs), [`/v2/orders`](#operation/getOrders), [`/v2/fee_recipients`](#operation/getFeeRecipients) and [`/v2/orderbook`](#operation/getOrderbook) endpoints. # Network Id All requests should be able to specify a **?networkId** query param for all supported networks. For example: @@ -78,7 +104,7 @@ Rate limit guidance for clients can be optionally returned in the response heade For example: ``` -curl -i https://api.example-relayer.com/v2/asset_pairs +$ curl -i https://api.example-relayer.com/v2/asset_pairs HTTP/1.1 200 OK Date: Mon, 20 Oct 2017 12:30:06 GMT Status: 200 OK -- cgit v1.2.3 From d7d51791a6bba5dae274c50257038b2bb8fb626b Mon Sep 17 00:00:00 2001 From: fragosti Date: Wed, 8 Aug 2018 14:50:06 -0700 Subject: Remove md hints because the static site cannot handle them --- packages/sra-api/src/md/introduction.md | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'packages/sra-api/src/md/introduction.md') diff --git a/packages/sra-api/src/md/introduction.md b/packages/sra-api/src/md/introduction.md index 76a144225..27b0db729 100644 --- a/packages/sra-api/src/md/introduction.md +++ b/packages/sra-api/src/md/introduction.md @@ -6,13 +6,13 @@ Use the [sra-report](https://github.com/0xProject/0x-monorepo/tree/development/p The [JSON schemas](http://json-schema.org/) for the API payloads and responses can be found in [@0xproject/json-schemas](https://github.com/0xProject/0x.js/tree/development/packages/json-schemas). Examples of each payload and response can be found in the library's [test suite](https://github.com/0xProject/0x.js/blob/development/packages/json-schemas/test/schema_test.ts#L1). -```bash +``` npm install @0xproject/json-schemas --save ``` You can easily validate your API's payloads and responses using the [@0xproject/json-schemas](https://github.com/0xProject/0x.js/tree/development/packages/json-schemas) package: -```js +``` import {SchemaValidator, ValidatorResult, schemas} from '@0xproject/json-schemas'; const {relayerApiTokenPairsResponseSchema} = schemas; @@ -28,7 +28,7 @@ const validatorResult: ValidatorResult = validator.validate(tokenPairsResponse, Requests that return potentially large collections should respond to the **?page** and **?per_page** parameters. For example: -```bash +``` $ curl https://api.example-relayer.com/v2/asset_pairs?page=3&per_page=20 ``` @@ -40,7 +40,7 @@ These requests include the [`/v2/asset_pairs`](#operation/getAssetPairs), [`/v2/ # Network Id All requests should be able to specify a **?networkId** query param for all supported networks. For example: -```bash +``` $ curl https://api.example-relayer.com/v2/asset_pairs?networkId=1 ``` If the query param is not provided, it should default to **1** (mainnet). -- cgit v1.2.3 From b2c666bb1f2830211db208ba8398f2de799c8ee6 Mon Sep 17 00:00:00 2001 From: fragosti Date: Thu, 9 Aug 2018 11:42:05 -0700 Subject: Apply prettier --- packages/sra-api/src/md/introduction.md | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) (limited to 'packages/sra-api/src/md/introduction.md') diff --git a/packages/sra-api/src/md/introduction.md b/packages/sra-api/src/md/introduction.md index 27b0db729..3e5e84e4c 100644 --- a/packages/sra-api/src/md/introduction.md +++ b/packages/sra-api/src/md/introduction.md @@ -34,15 +34,18 @@ $ curl https://api.example-relayer.com/v2/asset_pairs?page=3&per_page=20 Page numbering should be 1-indexed, not 0-indexed. If a query provides an unreasonable (ie. too high) `per_page` value, the response can return a validation error as specified in the [errors section](#section/Errors). If the query specifies a `page` that does not exist (ie. there are not enough `records`), the response should just return an empty `records` array. -All endpoints that are paginated should return a `total`, `page`, `perPage` and a `records` value in the top level of the collection. The value of `total` should be the total number of records for a given query, whereas `records` should be an array representing the response to the query for that page. `page` and `perPage`, are the same values that were specified in the request. See the note in [miscellaneous](#section/Misc.) about formatting `snake_case` vs. `lowerCamelCase`. +All endpoints that are paginated should return a `total`, `page`, `perPage` and a `records` value in the top level of the collection. The value of `total` should be the total number of records for a given query, whereas `records` should be an array representing the response to the query for that page. `page` and `perPage`, are the same values that were specified in the request. See the note in [miscellaneous](#section/Misc.) about formatting `snake_case` vs. `lowerCamelCase`. These requests include the [`/v2/asset_pairs`](#operation/getAssetPairs), [`/v2/orders`](#operation/getOrders), [`/v2/fee_recipients`](#operation/getFeeRecipients) and [`/v2/orderbook`](#operation/getOrderbook) endpoints. # Network Id + All requests should be able to specify a **?networkId** query param for all supported networks. For example: + ``` $ curl https://api.example-relayer.com/v2/asset_pairs?networkId=1 ``` + If the query param is not provided, it should default to **1** (mainnet). Networks and their Ids: @@ -54,8 +57,8 @@ Networks and their Ids: | 3 | Ropsten | | 4 | Rinkeby | - If a certain network is not supported, the response should **400** as specified in the [error response](#section/Errors) section. For example: - +If a certain network is not supported, the response should **400** as specified in the [error response](#section/Errors) section. For example: + ``` { "code": 100, @@ -112,6 +115,7 @@ X-RateLimit-Limit: 60 X-RateLimit-Remaining: 56 X-RateLimit-Reset: 1372700873 ``` + When a rate limit is exceeded, a status of **429 Too Many Requests** should be returned. # Errors @@ -129,6 +133,7 @@ Unless the spec defines otherwise, errors to bad requests should respond with HT | 501 | Not Implemented | ## Error reporting format + For all **400** responses, see the [error response schema](https://github.com/0xProject/0x-monorepo/blob/development/packages/json-schemas/schemas/relayer_api_error_response_schema.ts#L1). ``` @@ -168,9 +173,10 @@ Validation error codes: # Asset Data Encoding -As we now support multiple [token transfer proxies](https://github.com/0xProject/0x-protocol-specification/blob/master/v2/v2-specification.md#assetproxy), the identifier of which proxy to use for the token transfer must be encoded, along with the token information. Each proxy in 0x v2 has a unique identifier. If you're using 0x.js there will be helper methods for this [encoding](https://0xproject.com/docs/0x.js#zeroEx-encodeERC20AssetData) and [decoding](https://0xproject.com/docs/0x.js#zeroEx-decodeAssetProxyId). +As we now support multiple [token transfer proxies](https://github.com/0xProject/0x-protocol-specification/blob/master/v2/v2-specification.md#assetproxy), the identifier of which proxy to use for the token transfer must be encoded, along with the token information. Each proxy in 0x v2 has a unique identifier. If you're using 0x.js there will be helper methods for this [encoding](https://0xproject.com/docs/0x.js#zeroEx-encodeERC20AssetData) and [decoding](https://0xproject.com/docs/0x.js#zeroEx-decodeAssetProxyId). The identifier for the Proxy uses a similar scheme to [ABI function selectors](https://github.com/ethereum/wiki/wiki/Ethereum-Contract-ABI#function-selector). + ``` // ERC20 Proxy ID 0xf47261b0 bytes4(keccak256("ERC20Token(address)")) @@ -178,14 +184,16 @@ bytes4(keccak256("ERC20Token(address)")) bytes4(keccak256("ERC721Token(address,uint256)")) ``` -Asset data is encoded using [ABI encoding](https://solidity.readthedocs.io/en/develop/abi-spec.html). +Asset data is encoded using [ABI encoding](https://solidity.readthedocs.io/en/develop/abi-spec.html). + +For example, encoding the ERC20 token contract (address: 0x1dc4c1cefef38a777b15aa20260a54e584b16c48) using the ERC20 Transfer Proxy (id: 0xf47261b0) would be: -For example, encoding the ERC20 token contract (address: 0x1dc4c1cefef38a777b15aa20260a54e584b16c48) using the ERC20 Transfer Proxy (id: 0xf47261b0) would be: ``` 0xf47261b00000000000000000000000001dc4c1cefef38a777b15aa20260a54e584b16c48 ``` Encoding the ERC721 token contract (address: `0x371b13d97f4bf77d724e78c16b7dc74099f40e84`), token id (id: `99`, which hex encoded is `0x63`) and the ERC721 Transfer Proxy (id: 0x08e937fa) would be: + ``` 0x08e937fa000000000000000000000000371b13d97f4bf77d724e78c16b7dc74099f40e840000000000000000000000000000000000000000000000000000000000000063 ``` -- cgit v1.2.3