data-scientists/ocean.py/ocean-assets-tech-details.md
---
description: Technical details about OceanAssets functions
---
# Ocean Assets Tech Details
Through this class we can publish different types of assets & consume them to make 💲💲💲
### Creates URL Asset
* **create\_url\_asset**(`self`, `name: str`, `url: str`, `publisher_wallet`, `wait_for_aqua: bool = True` ) -> `tuple`
It is the most used functions in all the READMEs.
Creates asset of type "dataset", having `UrlFiles`, with good defaults.
It can be called after instantiating Ocean object.
**Parameters**
* `name` - name of the asset, `string`
* `url` - url that is stored in the asset, `string`
* `publisher_wallet` - wallet of the asset publisher/owner, `eth Account`
* `wait_for_aqua` - boolean value which default is `True`, waiting for aquarius to fetch the asset takes additional time, but if you want to be sure that your asset is indexed, keep the default value.
**Returns**
`tuple`
A tuple which contains the data NFT, datatoken and the data asset.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL178C1-L185C82)
<details>
<summary>Source code</summary>
{% code overflow="wrap" %}
```python
@enforce_types
def create_url_asset(
self, name: str, url: str, publisher_wallet, wait_for_aqua: bool = True
) -> tuple:
"""Create asset of type "data", having UrlFiles, with good defaults"""
metadata = self._default_metadata(name, publisher_wallet)
files = [UrlFile(url)]
return self._create_1dt(metadata, files, publisher_wallet, wait_for_aqua)
```
{% endcode %}
</details>
### Creates Algorithm Asset
* **create\_algo\_asset**(`self`, `name: str`, `url: str`, `publisher_wallet`, `image: str = "oceanprotocol/algo_dockers"`, `tag: str = "python-branin"`, `checksum: str = "sha256:8221d20c1c16491d7d56b9657ea09082c0ee4a8ab1a6621fa720da58b09580e4"`, `wait_for_aqua: bool = True`) -> `tuple`:
Create asset of type "algorithm", having `UrlFiles`, with good defaults.
It can be called after instantiating Ocean object.
**Parameters**:
* `name` - name of the asset, `string`
* `url` - url that is stored in the asset, `string`
* `publisher_wallet` - wallet of the asset publisher/owner, `eth Account`
* `image` - docker image of that algorithm, `string`
* `tag` - docker tag for that algorithm image, `string`
* `checksum` - docker checksum for algorithm's image, `string`
* `wait_for_aqua` - boolean value which default is `True`, waiting for aquarius to fetch the asset takes additional time, but if you want to be sure that your asset is indexed, keep the default value.
**Returns**
`tuple`
A tuple which contains the algorithm NFT, algorithm datatoken and the algorithm asset.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL146C4-L176C82)
<details>
<summary>Source code</summary>
{% code overflow="wrap" %}
```python
@enforce_types
def create_algo_asset(
self,
name: str,
url: str,
publisher_wallet,
image: str = "oceanprotocol/algo_dockers",
tag: str = "python-branin",
checksum: str = "sha256:8221d20c1c16491d7d56b9657ea09082c0ee4a8ab1a6621fa720da58b09580e4",
wait_for_aqua: bool = True,
) -> tuple:
"""Create asset of type "algorithm", having UrlFiles, with good defaults"""
if image == "oceanprotocol/algo_dockers" or tag == "python-branin":
assert image == "oceanprotocol/algo_dockers" and tag == "python-branin"
metadata = self._default_metadata(name, publisher_wallet, "algorithm")
metadata["algorithm"] = {
"language": "python",
"format": "docker-image",
"version": "0.1",
"container": {
"entrypoint": "python $ALGO",
"image": image,
"tag": tag,
"checksum": checksum,
},
}
files = [UrlFile(url)]
return self._create_1dt(metadata, files, publisher_wallet, wait_for_aqua)
```
{% endcode %}
</details>
### Creates Arweave Asset
* **create\_arweave\_asset**(`self`, `name: str`, `transaction_id: str`, `publisher_wallet`, `wait_for_aqua: bool = True`) -> `tuple`
Creates asset of type "data", having `ArweaveFile`, with good defaults.
It can be called after instantiating Ocean object.
**Parameters**
* `name` - name of the asset, `string`
* `transaction_id` - transaction id from the arweave file, `string`
* `publisher_wallet` - wallet of the asset publisher/owner, `eth Account`
* `wait_for_aqua` - boolean value which default is `True`, waiting for aquarius to fetch the asset takes additional time, but if you want to be sure that your asset is indexed, keep the default value.
**Returns**
`tuple`
A tuple which contains the data NFT, datatoken and the data asset.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL187C5-L198C82)
<details>
<summary>Source code</summary>
{% code overflow="wrap" %}
```python
@enforce_types
def create_arweave_asset(
self,
name: str,
transaction_id: str,
publisher_wallet,
wait_for_aqua: bool = True,
) -> tuple:
"""Create asset of type "data", having ArweaveFiles, with good defaults"""
metadata = self._default_metadata(name, publisher_wallet)
files = [ArweaveFile(transaction_id)]
return self._create_1dt(metadata, files, publisher_wallet, wait_for_aqua)
```
{% endcode %}
</details>
### Creates GraphQL Asset
* **create\_graphql\_asset**(`self`, `name: str`, `url: str`, `query: str`, `publisher_wallet`, `wait_for_aqua: bool = True`) -> `tuple`
Creates asset of type "data", having `GraphqlQuery` files, with good defaults.
It can be called after instantiating Ocean object.
**Parameters**
* `name` - name of the asset, `string`
* `url` - url of subgraph that you are using, `string`
* `query` - GraphQL query, `string`
* `publisher_wallet` - wallet of the asset publisher/owner, `eth Account`
* `wait_for_aqua` - boolean value which default is `True`, waiting for aquarius to fetch the asset takes additional time, but if you want to be sure that your asset is indexed, keep the default value.
**Returns**
`tuple`
A tuple which contains the data NFT, datatoken and the data asset.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL200C5-L212C82)
<details>
<summary>Source code</summary>
{% code overflow="wrap" %}
```python
@enforce_types
def create_graphql_asset(
self,
name: str,
url: str,
query: str,
publisher_wallet,
wait_for_aqua: bool = True,
) -> tuple:
"""Create asset of type "data", having GraphqlQuery files, w good defaults"""
metadata = self._default_metadata(name, publisher_wallet)
files = [GraphqlQuery(url, query)]
return self._create_1dt(metadata, files, publisher_wallet, wait_for_aqua)
```
{% endcode %}
</details>
### Creates Onchain Asset
* **create\_onchain\_asset**(`self`, `name: str`, `contract_address: str`, `contract_abi: dict`, `publisher_wallet`, `wait_for_aqua: bool = True`) -> `tuple`
Creates asset of type "data", having `SmartContractCall` files, with good defaults.
It can be called after instantiating Ocean object.
**Parameters**
* `name` - name of the asset, `string`
* `contract_address` - contract address that should be stored in the asset, `string`
* `contract_abi` - ABI of functions presented in the contract, `string`
* `publisher_wallet` - wallet of the asset publisher/owner, `eth Account`
* `wait_for_aqua` - boolean value which default is `True`, waiting for aquarius to fetch the asset takes additional time, but if you want to be sure that your asset is indexed, keep the default value.
**Returns**
`tuple`
A tuple which contains the data NFT, datatoken and the data asset.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL214C5-L229C1)
<details>
<summary>Source code</summary>
{% code overflow="wrap" %}
```python
@enforce_types
def create_onchain_asset(
self,
name: str,
contract_address: str,
contract_abi: dict,
publisher_wallet,
wait_for_aqua: bool = True,
) -> tuple:
"""Create asset of type "data", having SmartContractCall files, w defaults"""
chain_id = self._chain_id
onchain_data = SmartContractCall(contract_address, chain_id, contract_abi)
files = [onchain_data]
metadata = self._default_metadata(name, publisher_wallet)
return self._create_1dt(metadata, files, publisher_wallet, wait_for_aqua)
```
{% endcode %}
</details>
### Creates Asset (for advanced skills)
* **create**(`self`, `metadata: dict`, `publisher_wallet`, `credentials: Optional[dict] = None`, `data_nft_address: Optional[str] = None`, `data_nft_args: Optional[DataNFTArguments] = None`, `deployed_datatokens: Optional[List[Datatoken]] = None`, `services: Optional[list] = None`, `datatoken_args: Optional[List["DatatokenArguments"]] = None`, `encrypt_flag: Optional[bool] = True`, `compress_flag: Optional[bool] = True`, `wait_for_aqua: bool = True`) -> `tuple`
Register an asset on-chain. Asset = {data\_NFT, >=0 datatokens, DDO}
Creating/deploying a DataNFT contract and in the Metadata store (Aquarius).
**Parameters**
* `metadata`: `dictionary` conforming to the Metadata accepted by Ocean Protocol.
* `publisher_wallet`- `eth Account` of the publisher registering this asset.
* `credentials` - credentials `dictionary` necessary for the asset, which establish who can consume the asset and who cannot.
* `data_nft_address`- hex string, the address of the data NFT. The new asset will be associated with this data NFT address.
* `data_nft_args`- object of DataNFTArguments type if creating a new one.
* `deployed_datatokens`- list of datatokens which are already deployed.
* `services` - list of `Service` objects if you want to run multiple services for a datatoken or you have multiple datatokens with a single service each.
* `datatoken_args` - list of objects of `DatatokenArguments` type if creating a new datatokens.
* `encrypt_flag`- bool for encryption of the DDO.
* `compress_flag`- bool for compression of the DDO.
* `wait_for_aqua`- bool for spending time waiting for DDO to be updated in Aquarius.
**Returns**
`tuple`
A tuple which contains the data NFT, datatoken and the data asset.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL259C5-L390C43)
<details>
<summary>Source code</summary>
{% code overflow="wrap" %}
```python
def create(
self,
metadata: dict,
publisher_wallet,
credentials: Optional[dict] = None,
data_nft_address: Optional[str] = None,
data_nft_args: Optional[DataNFTArguments] = None,
deployed_datatokens: Optional[List[Datatoken]] = None,
services: Optional[list] = None,
datatoken_args: Optional[List["DatatokenArguments"]] = None,
encrypt_flag: Optional[bool] = True,
compress_flag: Optional[bool] = True,
wait_for_aqua: bool = True,
) -> Optional[DDO]:
self._assert_ddo_metadata(metadata)
provider_uri = DataServiceProvider.get_url(self._config_dict)
if not data_nft_address:
data_nft_args = data_nft_args or DataNFTArguments(
metadata["name"], metadata["name"]
)
data_nft = data_nft_args.deploy_contract(
self._config_dict, publisher_wallet
)
# register on-chain
if not data_nft:
logger.warning("Creating new NFT failed.")
return None, None, None
logger.info(f"Successfully created NFT with address {data_nft.address}.")
else:
data_nft = DataNFT(self._config_dict, data_nft_address)
# Create DDO object
ddo = DDO()
# Generate the did, add it to the ddo.
ddo.did = data_nft.calculate_did()
# Check if it's already registered first!
if self._aquarius.ddo_exists(ddo.did):
raise AquariusError(
f"Asset id {ddo.did} is already registered to another asset."
)
ddo.chain_id = self._chain_id
ddo.metadata = metadata
ddo.credentials = credentials if credentials else {"allow": [], "deny": []}
ddo.nft_address = data_nft.address
datatokens = []
if not deployed_datatokens:
services = []
for datatoken_arg in datatoken_args:
new_dt = datatoken_arg.create_datatoken(
data_nft, publisher_wallet, with_services=True
)
datatokens.append(new_dt)
services.extend(datatoken_arg.services)
for service in services:
ddo.add_service(service)
else:
if not services:
logger.warning("services required with deployed_datatokens.")
return None, None, None
datatokens = deployed_datatokens
dt_addresses = []
for datatoken in datatokens:
if deployed_datatokens[0].address not in data_nft.getTokensList():
logger.warning(
"some deployed_datatokens don't belong to the given data nft."
)
return None, None, None
dt_addresses.append(datatoken.address)
for service in services:
if service.datatoken not in dt_addresses:
logger.warning("Datatoken services mismatch.")
return None, None, None
ddo.add_service(service)
# Validation by Aquarius
_, proof = self.validate(ddo)
proof = (
proof["publicKey"],
proof["v"],
proof["r"][0],
proof["s"][0],
)
document, flags, ddo_hash = self._encrypt_ddo(
ddo, provider_uri, encrypt_flag, compress_flag
)
data_nft.setMetaData(
0,
provider_uri,
Web3.toChecksumAddress(publisher_wallet.address.lower()).encode("utf-8"),
flags,
document,
ddo_hash,
[proof],
{"from": publisher_wallet},
)
# Fetch the ddo on chain
if wait_for_aqua:
ddo = self._aquarius.wait_for_ddo(ddo.did)
return (data_nft, datatokens, ddo)
```
{% endcode %}
**Publishing Alternatives**
Here are some examples similar to the `create()` above, but exposes more fine-grained control.
In the same python console:
```python
# Specify metadata and services, using the Branin test dataset
date_created = "2021-12-28T10:55:11Z"
metadata = {
"created": date_created,
"updated": date_created,
"description": "Branin dataset",
"name": "Branin dataset",
"type": "dataset",
"author": "Trent",
"license": "CC0: PublicDomain",
}
# Use "UrlFile" asset type. (There are other options)
from ocean_lib.structures.file_objects import UrlFile
url_file = UrlFile(
url="https://raw.githubusercontent.com/trentmc/branin/main/branin.arff"
)
# Publish data asset
from ocean_lib.models.datatoken_base import DatatokenArguments
_, _, ddo = ocean.assets.create(
metadata,
{"from": alice},
datatoken_args=[DatatokenArguments(files=[url_file])],
)
```
**DDO Encryption or Compression**
The DDO is stored on-chain. It's encrypted and compressed by default. Therefore it supports GDPR "right-to-be-forgotten" compliance rules by default.
You can control this during `create()`:
* To disable encryption, use `ocean.assets.create(..., encrypt_flag=False)`.
* To disable compression, use `ocean.assets.create(..., compress_flag=False)`.
* To disable both, use `ocean.assetspy.create(..., encrypt_flag=False, compress_flag=False)`.
**Create **_**just**_** a data NFT**
Calling `create()` like above generates a data NFT, a datatoken for that NFT, and a ddo. This is the most common case. However, sometimes you may want _just_ the data NFT, e.g. if using a data NFT as a simple key-value store. Here's how:
```python
data_nft = ocean.data_nft_factory.create({"from": alice}, 'NFT1', 'NFT1')
```
If you call `create()` after this, you can pass in an argument `data_nft_address:string` and it will use that NFT rather than creating a new one.
**Create a datatoken from a data NFT**
Calling `create()` like above generates a data NFT, a datatoken for that NFT, and a ddo object. However, we may want a second datatoken. Or, we may have started with _just_ the data NFT, and want to add a datatoken to it. Here's how:
```python
datatoken = data_nft.create_datatoken({"from": alice}, "Datatoken 1", "DT1")
```
If you call `create()` after this, you can pass in an argument `deployed_datatokens:List[Datatoken1]` and it will use those datatokens during creation.
**Create an asset & pricing schema simultaneously**
Ocean Assets allows you to bundle several common scenarios as a single transaction, thus lowering gas fees.
Any of the `ocean.assets.create_<type>_asset()` functions can also take an optional parameter that describes a bundled pricing schema (Dispenser or Fixed Rate Exchange).
Here is an example involving an exchange:
{% code overflow="wrap" %}
```python
from ocean_lib.models.fixed_rate_exchange import ExchangeArguments
(data_nft, datatoken, ddo) = ocean.assets.create_url_asset(
name,
url,
{"from": alice},
pricing_schema_args=ExchangeArguments(rate=to_wei(3), base_token_addr=ocean.OCEAN_address, dt_decimals=18)
)
assert len(datatoken.get_exchanges()) == 1
```
{% endcode %}
</details>
### Updates Asset
* **update**(`self`, `ddo: DDO`, `publisher_wallet`, `provider_uri: Optional[str] = None`, `encrypt_flag: Optional[bool] = True`, `compress_flag: Optional[bool] = True`) -> `Optional[DDO]`
Updates a ddo on-chain.
**Parameters**
* `ddo` - DDO to update
* `publisher_wallet` - who published this DDO
* `provider_uri` - URL of service provider. This will be used as base to construct the serviceEndpoint for the `access` (download) service.
* `encrypt_flag` - boolean value for encryption the DDO
* `compress_flag` - boolean value for compression the DDO
**Returns**
`DDO` or `None`
The updated DDO, or `None` if updated DDO not found in Aquarius.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL392C5-L454C19)
<details>
<summary>Source code</summary>
{% code overflow="wrap" %}
```python
@enforce_types
def update(
self,
ddo: DDO,
publisher_wallet,
provider_uri: Optional[str] = None,
encrypt_flag: Optional[bool] = True,
compress_flag: Optional[bool] = True,
) -> Optional[DDO]:
self._assert_ddo_metadata(ddo.metadata)
if not provider_uri:
provider_uri = DataServiceProvider.get_url(self._config_dict)
assert ddo.nft_address, "need nft address to update a ddo"
data_nft = DataNFT(self._config_dict, ddo.nft_address)
assert ddo.chain_id == self._chain_id
for service in ddo.services:
service.encrypt_files(ddo.nft_address)
# Validation by Aquarius
validation_result, errors_or_proof = self.validate(ddo)
if not validation_result:
msg = f"DDO has validation errors: {errors_or_proof}"
logger.error(msg)
raise ValueError(msg)
document, flags, ddo_hash = self._encrypt_ddo(
ddo, provider_uri, encrypt_flag, compress_flag
)
proof = (
errors_or_proof["publicKey"],
errors_or_proof["v"],
errors_or_proof["r"][0],
errors_or_proof["s"][0],
)
tx_result = data_nft.setMetaData(
0,
provider_uri,
Web3.toChecksumAddress(publisher_wallet.address.lower()).encode("utf-8"),
flags,
document,
ddo_hash,
[proof],
{"from": publisher_wallet},
)
ddo = self._aquarius.wait_for_ddo_update(ddo, tx_result.txid)
return ddo
```
{% endcode %}
</details>
### Resolves Asset
* **resolve**(`self`, `did: str`) -> `"DDO"`
Resolves the asset from Metadata Cache store (Aquarius).
**Parameter**
* `did` - identifier of the DDO to be searched & resolved in Aquarius
**Returns**
`DDO`
Returns DDO instance.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL456C5-L458C43)
<details>
<summary>Source code</summary>
```python
@enforce_types
def resolve(self, did: str) -> "DDO":
return self._aquarius.get_ddo(did)
```
</details>
### Searches Assets by Text
* **search**(`self`, `text: str`) -> `list`
Searches a DDO by a specific text.
**Parameter**
* `text` - string text to search for assets which include it.
**Returns**
`list`
A list of DDOs which have matches with the text provided as parameter.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL460C4-L475C10)
<details>
<summary>Source code</summary>
```python
@enforce_types
def search(self, text: str) -> list:
"""
Search for DDOs in aquarius that contain the target text string
:param text - target string
:return - List of DDOs that match with the query
"""
logger.info(f"Search for DDOs containing text: {text}")
text = text.replace(":", "\\:").replace("\\\\:", "\\:")
return [
DDO.from_dict(ddo_dict["_source"])
for ddo_dict in self._aquarius.query_search(
{"query": {"query_string": {"query": text}}}
)
if "_source" in ddo_dict
]
```
</details>
### Searches Asset by GraphQL Query
* **query**(`self`, `query: dict`) -> `list`
Searches a DDO by a specific query.
**Parameter**
* `query` - dictionary type query to search for assets which include it.
**Returns**
`list`
A list of DDOs which have matches with the query provided as parameter.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL477C4-L490C10)
<details>
<summary>Source code</summary>
{% code overflow="wrap" %}
```python
@enforce_types
def query(self, query: dict) -> list:
"""
Search for DDOs in aquarius with a search query dict
:param query - dict with query parameters
More info at: https://docs.oceanprotocol.com/api-references/aquarius-rest-api
:return - List of DDOs that match the query.
"""
logger.info(f"Search for DDOs matching query: {query}")
return [
DDO.from_dict(ddo_dict["_source"])
for ddo_dict in self._aquarius.query_search(query)
if "_source" in ddo_dict
]
```
{% endcode %}
</details>
### Downloads Asset
* **download\_asset**(`self`, `ddo: DDO`, `consumer_wallet`, `destination: str`, `order_tx_id: Union[str, bytes]`, `service: Optional[Service] = None`, `index: Optional[int] = None`, `userdata: Optional[dict] = None`) -> `str`
Downloads the asset from Ocean Market.
**Parameters**
* `ddo` - DDO to be downloaded.
* `consumer_wallet` - eth Account for the wallet that "ordered" the asset.
* `destination` - destination path, as string, where the asset will be downloaded.
* `order_tx_id` - transaction ID for the placed order, string and bytes formats are accepted.
**Optional parameters**
* `service` - optionally if you want to provide the `Service` object through you downloaded the asset.
* `index` - optionally if you want to download certain files, not the whole asset, you can specify how many files you want to download as positive `integer` format.
* `userdata` - `dictionary` additional data from user.
**Returns**
`str`
The full path to the downloaded file as `string`.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL492C5-L516C20)
<details>
<summary>Source code</summary>
{% code overflow="wrap" %}
```python
@enforce_types
def download_asset(
self,
ddo: DDO,
consumer_wallet,
destination: str,
order_tx_id: Union[str, bytes],
service: Optional[Service] = None,
index: Optional[int] = None,
userdata: Optional[dict] = None,
) -> str:
service = service or ddo.services[0] # fill in good default
if index is not None:
assert isinstance(index, int), logger.error("index has to be an integer.")
assert index >= 0, logger.error("index has to be 0 or a positive integer.")
assert (
service and service.type == ServiceTypes.ASSET_ACCESS
), f"Service with type {ServiceTypes.ASSET_ACCESS} is not found."
path: str = download_asset_files(
ddo, service, consumer_wallet, destination, order_tx_id, index, userdata
)
return path
```
{% endcode %}
</details>
### Pays for Access Service
* **pay\_for\_access\_service**(`self`, `ddo: DDO`, `wallet`, `service: Optional[Service] = None`, `consume_market_fees: Optional[TokenFeeInfo] = None`, `consumer_address: Optional[str] = None`, `userdata: Optional[dict] = None`)
Pays for access service by calling initialize endpoint from Provider and starting the order.
**Parameters**
* `ddo` - DDO to be downloaded.
* `wallet`- eth Account for the wallet that pays for the asset.
**Optional parameters**
* `service` - optionally if you want to provide the `Service` object through you downloaded the asset.
* `consume_market_fees` - `TokenFeeInfo` object which contains consume market fee address, amount and token address.
* `consumer_address` - address for the consumer which pays for the access.
* `userdata` - `dictionary` additional data from user.
**Returns**
`str`
Return value is a hex string for transaction hash which denotes the proof of starting order.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL518C5-L571C28)
<details>
<summary>Source code</summary>
{% code overflow="wrap" %}
```python
@enforce_types
def pay_for_access_service(
self,
ddo: DDO,
wallet,
service: Optional[Service] = None,
consume_market_fees: Optional[TokenFeeInfo] = None,
consumer_address: Optional[str] = None,
userdata: Optional[dict] = None,
):
# fill in good defaults as needed
service = service or ddo.services[0]
consumer_address = consumer_address or wallet.address
# main work...
dt = Datatoken(self._config_dict, service.datatoken)
balance = dt.balanceOf(wallet.address)
if balance < to_wei(1):
raise InsufficientBalance(
f"Your token balance {balance} {dt.symbol()} is not sufficient "
f"to execute the requested service. This service "
f"requires 1 wei."
)
consumable_result = is_consumable(
ddo,
service,
{"type": "address", "value": wallet.address},
userdata=userdata,
)
if consumable_result != ConsumableCodes.OK:
raise AssetNotConsumable(consumable_result)
data_provider = DataServiceProvider
initialize_args = {
"did": ddo.did,
"service": service,
"consumer_address": consumer_address,
}
initialize_response = data_provider.initialize(**initialize_args)
provider_fees = initialize_response.json()["providerFee"]
receipt = dt.start_order(
consumer=consumer_address,
service_index=ddo.get_index_of_service(service),
provider_fees=provider_fees,
consume_market_fees=consume_market_fees,
transaction_parameters={"from": wallet},
)
return receipt.txid
```
{% endcode %}
</details>
### Pays for Compute Service
* **pay\_for\_compute\_service**(`self`, `datasets: List[ComputeInput]`, `algorithm_data: Union[ComputeInput, AlgorithmMetadata]`, `compute_environment: str`, `valid_until: int`, `consume_market_order_fee_address: str`, `wallet`, `consumer_address: Optional[str] = None`)
Pays for compute service by calling `initializeCompute` endpoint from Provider to retrieve the provider fees and starting the order afterwards.
**Parameters**
* `datasets` - list of `ComputeInput` objects, each of them includes mandatory the DDO and service.
* `algorithm_data` - which can be either a `ComputeInput` object which contains the whole DDO and service, either provide just the algorithm metadata as `AlgorithmMetadata`.
* `compute_environment` - `string` that represents the ID from the chosen C2D environment.
* `valid_until` - `UNIX timestamp` which represents until when the algorithm can be used/run.
* `consume_market_order_fee_address` - string address which denotes the consume market fee address for that order and can be the wallet address itself.
* `wallet` - the `eth Account` which pays for the compute service
**Optional parameters**
* `consumer_address` - is the string address of the C2D environment consumer.
**Returns**
`tuple`
Return value is a tuple composed of list of datasets and algorithm data (if exists in result), `(datasets, algorithm_data)`.
**Defined in**
[ocean/ocean_assets.py](https://github.com/oceanprotocol/ocean.py/blob/4aa12afd8a933d64bc2ed68d1e5359d0b9ae62f9/ocean_lib/ocean/ocean_assets.py#LL573C5-L627C30)
<details>
<summary>Source code</summary>
```python
@enforce_types
def pay_for_compute_service(
self,
datasets: List[ComputeInput],
algorithm_data: Union[ComputeInput, AlgorithmMetadata],
compute_environment: str,
valid_until: int,
consume_market_order_fee_address: str,
wallet,
consumer_address: Optional[str] = None,
):
data_provider = DataServiceProvider
if not consumer_address:
consumer_address = wallet.address
initialize_response = data_provider.initialize_compute(
[x.as_dictionary() for x in datasets],
algorithm_data.as_dictionary(),
datasets[0].service.service_endpoint,
consumer_address,
compute_environment,
valid_until,
)
result = initialize_response.json()
for i, item in enumerate(result["datasets"]):
self._start_or_reuse_order_based_on_initialize_response(
datasets[i],
item,
TokenFeeInfo(
consume_market_order_fee_address,
datasets[i].consume_market_order_fee_token,
datasets[i].consume_market_order_fee_amount,
),
wallet,
consumer_address,
)
if "algorithm" in result:
self._start_or_reuse_order_based_on_initialize_response(
algorithm_data,
result["algorithm"],
TokenFeeInfo(
address=consume_market_order_fee_address,
token=algorithm_data.consume_market_order_fee_token,
amount=algorithm_data.consume_market_order_fee_amount,
),
wallet,
consumer_address,
)
return datasets, algorithm_data
return datasets, None
```
</details>