feat: generate tasks from retrievable deals

[bajtos]

Quoting from the design doc:

Rework the code defining retrieval tasks for a new Meridian round to pick CIDs from the list of FIL+ LDN deals. Set columns provider_address and protocol to NULL.

In the future, we will need metadata to match IPNI responses to this particular deal. We don’t have that yet, so let's keep the schema simple and the table small in size for now.

Verify that the response of GET /rounds/meridian/{contract}/{round-index} converts NULL values in provider_address and protocol to undefined values in JavaScript, therefore excluding these fields from the JSON response.

The goal here is to preserve the provider address & protocol in the responses for older rounds where the retrieval tasks were defined with the provider address and protocol to use.

Links:

• https://www.notion.so/pl-strflt/Moving-IPNI-queries-to-Spark-checkers-c58175c0f1c841e6bb82ac44a1472a98
• CID sampling v0.2 spark-checker#40

[bajtos]

This is a breaking change for Spark checker nodes. Nodes running the Spark version older than 1.8.0 will stop earning rewards.

I guess we should wait with this change until we modify spark-api to start rejecting outdated clients on Feb 15th.

[juliangruber]

This is a breaking change for Spark checker nodes. Nodes running the Spark version older than 1.8.0 will stop earning rewards.

I guess we should wait with this change until we modify spark-api to start rejecting outdated clients on Feb 15th.

Yeah now that we have communicated this I think we have to