fix yaml config file parsing, a few fixes and comments

CHANGELOG.md

@@ -16,8 +16,12 @@ If you were at `firehose-core` version `1.0.0` and are bumping to `1.1.0`, you s
   - `advertise-block-features` List of features describing the blocks (optional)
   - `advertise-block-id-encoding` Encoding format of the block ID [BLOCK_ID_ENCODING_BASE58, BLOCK_ID_ENCODING_BASE64, BLOCK_ID_ENCODING_BASE64URL, BLOCK_ID_ENCODING_HEX, BLOCK_ID_ENCODING_0X_HEX] (required, unless the block type is in the "well-known" list)
 
-* Add a well-known list of chains (hard-coded in `wellknown/chains.go` to help automatically determine the 'advertise' flag values)
+* Add a well-known list of chains (hard-coded in `wellknown/chains.go` to help automatically determine the 'advertise' flag values). Users are encouraged to propose Pull Requests to add more chains to the list.
 * The new info endpoint adds a mandatory fetching of the first streamable block on startup, with a failure if no block can be fetched after 3 minutes and you are running `firehose` or `substreams-tier1` service.
+  It validates the following on a well-known chain:
+    - if the first-streamable-block Num/ID match the genesis block of a known chain, e.g. `matic`, it will refuse another value for `advertise-chain-name` than `matic` or one of its aliases (`polygon`)
+    - If the first-streamable-block does not match any known chain, it will require the `advertise-chain-name` to be non-empty
+    - If the first-streamable-block type is unknown (i.e. not ethereum, solana, near, cosmos, bitcoin...), it will require the user to provide `advertise-chain-name` as well as `advertise-block-id-encoding`
 
 * Substreams: revert module hash calculation from `v1.5.5`, when using a non-zero firstStreamableBlock. Hashes will now be the same even if the chain's first streamable block affects the initialBlock of a module.
 * Substreams: add `--substreams-block-execution-timeout` flag (default 3 minutes) to prevent requests stalling

cmd/setup.go

@@ -51,6 +51,10 @@ func setupCmd(cmd *cobra.Command, binaryName string) error {
 				return fmt.Errorf("invalid flag %s in config file under command %s", k, subCommand)
 			}
 
+			// Keep compatibility with config files, allow empty value to unset the flag
+			if v == nil {
+				v = ""
+			}
 			viper.SetDefault(flag.viperKey, v)
 
 			// For root command, we want to keep compatibility for `viper.GetXXX("global-<flag>")` to work with config loaded value

firehose/info/endpoint_info.go

@@ -102,6 +102,7 @@ func (s *InfoServer) getBlockFromMergedBlocksStore(ctx context.Context, blockNum
 
 		block, err := bstream.FetchBlockFromMergedBlocksStore(ctx, blockNum, mergedBlocksStore)
 		if err != nil {
+			time.Sleep(time.Millisecond * 500)
 			continue
 		}
 		return block
@@ -132,6 +133,7 @@ func (s *InfoServer) getBlockFromOneBlockStore(ctx context.Context, blockNum uin
 
 		block, err := bstream.FetchBlockFromOneBlockStore(ctx, blockNum, "", oneBlockStore)
 		if err != nil {
+			time.Sleep(time.Millisecond * 500)
 			continue
 		}
 		return block

launcher/config.go

@@ -10,8 +10,8 @@ import (
 var Config map[string]*CommandConfig
 
 type CommandConfig struct {
-	Args  []string          `json:"args"`
-	Flags map[string]string `json:"flags"`
+	Args  []string       `json:"args"`
+	Flags map[string]any `json:"flags"`
 }
 
 // Load reads a YAML config, and sets the global DfuseConfig variable

well-known/chains.go

@@ -13,10 +13,15 @@ type WellKnownProtocol struct {
 }
 
 type Chain struct {
-	Name    string
+	// Canonical name, from https://thegraph.com/docs/en/developing/supported-networks/
+	Name string
+	// Aliases are other names that can be used to refer to the chain, for example 'polygon' is a popular name for the chain 'matic'
 	Aliases []string
 	// Genesis block here is actually the "lowest possible" first streamable block through firehose blocks.
 	// In most cases, it matches the "genesis block" of the chain.
+	// It must match the value of the `sf.bstream.v1.Block.id` field (https://github.com/streamingfast/bstream/blob/develop/proto/sf/bstream/v1/bstream.proto#L71)
+	// and it follows the encoding specified in the `BytesEncoding` field of the WellKnownProtocol
+	// You can generally get the genesis block ID by running `firecore tools print merged-blocks <path/to/merged-blocks> <first-streamable-block-number>` on the merged-blocks
 	GenesisBlockID     string
 	GenesisBlockNumber uint64
 }