The basic premise is true. Ethereum nodes do not provide even basic search/querying features out of the box so you have to rely on centralized services to index the blockchain data for querying. So if you want to build anything useful which integrates with Ethereum in any way, you need to trust a centralized service provider to accurately report the data... I was shocked when I tried to integrate with Ethereum for the first time. It almost seems as though they have made it difficult to integrate with on purpose.
It's been over a decade. Couldn't they have written some kind of open source service which exposes the Ethereum node's data via a simple REST HTTP API? This would not be a difficult project to implement.
What data were you looking for? geth provides a JSON RPC interface. Ethereum is general purpose so you'll need to know how a particular contract works to get information out of it but some contracts adhere to standards like ERC-20.
Ethereum launched six years ago, by the way (not a decade).
Does geth provide a basic search/querying feature? For example like searching for a list of transactions sent to and from a specific account.
But doesn't geth require me to setup and sync my own Ethereum node from scratch? I heard it consumes 300GB minimum. It would be great if I could just query some random node on testnet for example for testing my service before I commit to launching a node.
There are schemes for verifiable query services against the chain (e.g. VulcanizeDB) but most folks seem to just connect to someone else's node and hope it answers truthfully.
I feel that they should promote this more. Not everyone can afford to sync their own 300GB DB... Especially for testing. As a developer, I want to test things with someone else's backend before I even bother setting up my own.
It's been over a decade. Couldn't they have written some kind of open source service which exposes the Ethereum node's data via a simple REST HTTP API? This would not be a difficult project to implement.