# Update a DID-Linked Resource The purpose of this document is to describe how someone can create a *new* Resource on under an existing *Collection*. This tutorial uses the [cheqd Cosmos CLI](https://docs.cheqd.io/node/getting-started/cheqd-cli), similar to the [creating a new Resource tutorial](/product/advanced/tooling/cheqd-node-cli/create-resource.md). ## Pre-requisites 1. Install the latest stable cheqd-node CLI, either as a [standalone binary](https://github.com/cheqd/cheqd-node/releases/latest) or [Docker container image](https://github.com/cheqd/cheqd-node/pkgs/container/cheqd-node). 2. Acquire test CHEQ tokens through [our testnet faucet](https://testnet-faucet.cheqd.io) (if creating it on our testnet), or [CHEQ tokens](https://app.osmosis.zone/?from=OSMO\&to=CHEQ) (if you plan on creating it on mainnet). 3. An [existing DID + DIDDoc created on cheqd ledger](/product/advanced/tooling/cheqd-node-cli/create-did.md) 4. Having [a Resource already created](/product/advanced/tooling/cheqd-node-cli/create-resource.md) under this DIDDoc Collection ## Adding a new Resource to an existing DIDDoc Collection ### 1. Generate a new UUID for the new Resource version [UUIDs are used to identify Resources](https://en.wikipedia.org/wiki/Universally_unique_identifier). On Unix systems, the `uuidgen` tool can be used to generate a new UUID: ```bash $ uuidgen c8ef6d88-ee0c-4ca4-9fd6-f9e17f6f8f3f ``` ### 2. Prepare a file with Resource content Resource content should be placed in a file and stored locally. ### 3. Publish the new Resource version to the ledger Resources with the same Collection ID and name are grouped into version sets. Each resource in such a set has a link to the previous version (except the first version) and the next version (if it's not the most recent version). To create a resource and mark it as a new version within a particular group, we need to use the same `collection-id` and `name` as in the previous version. Links between versions will be created automatically. New versions have dedicated unique IDs and can be referenced and retrieved as any other resources. #### Command ```bash cheqd-noded tx resource create [payload-file] [resource-data-file] [flags] ``` #### Parameters * `payload-file` - file with JSON formatted payload. The format and structure can be found in example * `resource-data-file` - file which will be sent to the ledger as a `data`. Can be a picture or an image or whatever you want. * `flags` - additional parameters like, `--gas` or `--from`. `--fees` should match the price of the [speicfic resource file type defined here](/product/advanced/tooling/cheqd-node-cli/create-resource.md#understanding-resource-fees). #### Example ```bash cheqd-noded tx resource create \ --chain-id cheqd \ --keyring-backend test \ --output json \ --fees 10000000000ncheq \ --gas auto \ --gas-adjustment 1.8 \ --from base_account \ [payload.json] [resource.jpeg] ``` where `payload.json` is: ```json { "payload": { "data": null, "collectionId": "b0ca0b75-ca6a-4674-a261-45f6dd0c9c77", "id": "c8ef6d88-ee0c-4ca4-9fd6-f9e17f6f8f3f", "name": "TestResource", "version": "1.0", "resourceType": "TestType", "alsoKnownAs": [] }, "signInputs": [ { "verificationMethodId": "did:cheqd:testnet:b0ca0b75-ca6a-4674-a261-45f6dd0c9c77#key1", "privKey": "y4B5qis9BXUq/mODsrWtS3q5ejOk/okSIXlX1/a9HvuG3PgYmekfQmq3QhJ4JSzN/rkiGCQDNKoTXMmxuXDHbg==" } ] } ``` After you execute the command, you will receive `"code": 0"` if the resource was successfully written to the ledger. Otherwise, the `raw_logs` field in the response can help figure out why something went wrong. For example: ```json { "code": 1201, "data": "", "raw_log": "failed to execute message; message index: 0: id:cheqd:testnet:fcbarcelona: DID Doc not found" } ``` ### 4. Check that new Resource version was successfully written to the ledger Finally, to check that the resource was successfully written, we can use the following query: ```bash cheqd-noded query resource specific-resource \ \ \ --node https://rpc.cheqd.network:443 ``` #### Parameters * ``: The **same unique identifier** as that after the namespace of the corresponding DID created in step 1 * ``: Unique ID of the resource within the collection of resources associated with the DIDDoc #### Example ```bash cheqd-noded query resource specific-resource \ c82f2b02-bdab-4dd7-b833-3e143745d612 \ c8ef6d88-ee0c-4ca4-9fd6-f9e17f6f8f3f \ --node https://rpc.cheqd.net:443 --output json ``` #### Result ```json { "resource": { "resource": { "data": "..." }, "metadata": { "collection_id": "c82f2b02-bdab-4dd7-b833-3e143745d612", "id": "c8ef6d88-ee0c-4ca4-9fd6-f9e17f6f8f3f", "name": "EventBrite Logo", "version": "", "resource_type": "image/png", "also_known_as": [ { "uri": "did:cheqd:mainnet:c82f2b02-bdab-4dd7-b833-3e143745d612/resources/c8ef6d88-ee0c-4ca4-9fd6-f9e17f6f8f3f", "description": "did-url" } ], "media_type": "image/svg+xml", "created": "2022-11-17T10:35:23Z", "checksum": "a95380f460e63ad939541a57aecbfd795fcd37c6d78ee86c885340e33a91b559", "previous_version_id": "3e6bd814-6851-4c8a-b114-c64f035ef590", "next_version_id": "" } } } ``` Notice that `previous_version_id` is not empty and pointing to the previously created resource with `id` : `3e6bd814-6851-4c8a-b114-c64f035ef590`. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.cheqd.io/product/advanced/tooling/cheqd-node-cli/update-resource.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.