Feature/issue 210 fullblock streaming algsoch

[algsoch]

Summary

Implements Issue #210: FullBlock streaming API method for explorer-backend.

This PR adds a new streaming endpoint that returns complete block data including all transactions, inputs, outputs, and assets. The implementation follows existing patterns from streamBlocks and streamBlockSummaries endpoints.

---

🎯 New Feature

Endpoint

GET /api/v1/blocks/stream/full?minGlobalIndex={gix}&limit={limit}

Parameters:

• minGlobalIndex (Long): Starting global index - returns blocks with height >= corresponding height
• limit (Int): Maximum number of blocks to return (capped by server settings)

Returns: Stream of FullBlockInfo objects containing:

• ✅ Block header (id, height, timestamp, difficulty, etc.)
• ✅ All transactions with complete details
• ✅ All transaction inputs
• ✅ All transaction data inputs
• ✅ All transaction outputs
• ✅ All assets
• ✅ Block extension
• ✅ AD proofs
• ✅ Block size information

---

Changes Made

1. HeaderQuerySet.scala

Added SQL query to fetch headers by global index:

def getHeadersAfterGix(minGix: Long, limit: Int): Query0[Header]

2. HeaderRepo.scala

Added repository method:

def streamHeadersAfterGix(minGix: Long, limit: Int): S[D, Header]

3. Blocks.scala (Service)

Added streaming service method:

def streamFullBlocks(minGix: Long, limit: Int): Stream[F, FullBlockInfo]

4. BlocksEndpointDefs.scala

Added endpoint definition:

def streamFullBlocksDef: Endpoint[(Long, Int), ApiErr, fs2.Stream[F, Byte], Fs2Streams[F]]

5. BlocksRoutes.scala

Added route handler:

private def streamFullBlocksR: HttpRoutes[F]

---

Why This Approach?

1. Consistent with existing patterns: Follows the same structure as streamBlocks and streamBlockSummaries
2. Efficient streaming: Uses fs2 streams for memory-efficient data transfer
3. Reuses existing logic: Leverages getFullBlockInfo method already in the service
4. Proper layer separation: SQL → Repository → Service → Route

---

Usage Example

curl "http://localhost:8080/api/v1/blocks/stream/full?minGlobalIndex=1000000&limit=100"

Returns a JSON stream of full block data starting from height 1,000,000, limited to 100 blocks.

---

Fixes: #210

[Copilot]

Pull request overview

This pull request combines two separate feature implementations: Issue #210 (FullBlock streaming API) and Issue #259 (globalIndex recalculation after blockchain reorganization). While the PR title and description focus on Issue #210, the changes include substantial code for Issue #259 as well, making this effectively two PRs bundled together.

Key Changes:

• Added new /api/v1/blocks/stream/full endpoint to stream complete block data with all transactions and related entities
• Implemented globalIndex recalculation mechanism triggered during blockchain reorganization
• Added five markdown documentation files containing PR meta-information and team collaboration notes

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 11 comments.

Show a summary per file

File	Description
HeaderQuerySet.scala	Added getHeadersAfterGix query to fetch headers by height with main_chain filter
HeaderRepo.scala	Added streamHeadersAfterGix repository method for streaming headers
Blocks.scala	Added streamFullBlocks service method using flatMap over getFullBlockInfo
BlocksEndpointDefs.scala	Added streamFullBlocksDef endpoint definition for full block streaming
BlocksRoutes.scala	Added streamFullBlocksR route handler integrating the new endpoint
TransactionQuerySet.scala	Added recalculateGlobalIndexFromHeight SQL query with window function approach
TransactionRepo.scala	Added repository method for globalIndex recalculation
ChainIndexer.scala	Modified updateChainStatus to trigger globalIndex recalculation on reorgs
PR_DESCRIPTION_*.md	Multiple markdown files with PR creation instructions and team strategy (should be removed)
IMPLEMENTATION_COMPLETE.md	Meta-documentation about PR submission (should be removed)
CREATE_PR_NOW.md	Step-by-step PR creation guide (should be removed)

---

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[Copilot]

The comment on line 237 states "FIX FOR ISSUE #259" but the PR title and description indicate this PR is for "Issue #210". There's a mismatch between what the PR claims to implement (FullBlock streaming API for Issue #210) and what this code comment references (Issue #259 about globalIndex recalculation).

This appears to be two separate features bundled into one PR, which makes review and version control history more difficult. Consider splitting these into separate PRs, or at minimum update the PR title/description to accurately reflect that both Issue #210 AND Issue #259 are being addressed.

[Copilot]

The SQL query uses FOR UPDATE locking within a CTE (Common Table Expression) that's used in an UPDATE statement. While PostgreSQL supports this, the FOR UPDATE clause in the ordered_txs CTE is ineffective here because:

1. The UPDATE statement already acquires the necessary locks on the rows being updated
2. FOR UPDATE in a CTE that feeds an UPDATE doesn't provide additional concurrency protection
3. The rows selected in ordered_txs are immediately updated, so PostgreSQL's default transaction isolation already prevents dirty reads

The FOR UPDATE clause here is redundant and adds unnecessary complexity. The UPDATE statement itself provides sufficient locking guarantees for this operation.

Suggested change

| FOR UPDATE -- Explicit locking for concurrent safety

[Copilot]

The comment on line 247 states "This ensures ORDER BY timestamp = ORDER BY globalIndex invariant" but this is misleading. The recalculation actually ensures that ORDER BY inclusion_height, timestamp, index equals ORDER BY global_index, not just timestamp alone. The ordering includes three fields (height, timestamp, and transaction index within a block), not just timestamp.

This could mislead future maintainers about what the global_index actually represents and what ordering guarantees it provides.

Suggested change

	// This ensures ORDER BY timestamp = ORDER BY globalIndex invariant
	// This ensures ORDER BY (inclusion_height, timestamp, index) = ORDER BY globalIndex invariant

[Copilot]

These markdown files (PR_DESCRIPTION_*.md, IMPLEMENTATION_COMPLETE.md, CREATE_PR_NOW.md) appear to be development/collaboration documents that were accidentally committed to the repository. These files contain:

• Draft status notes and internal team discussions
• Step-by-step instructions for creating a PR
• Bounty and hackathon competition information
• Internal team strategy and comparisons with competing PRs
• Implementation checklists with honest admissions like "Not compiled yet"

These types of files should not be committed to the main codebase as they:

1. Clutter the repository with meta-information about the PR itself
2. Contain information only relevant during the PR creation process
3. Will become stale/outdated once the PR is merged
4. Are not part of the actual project documentation

These files should be removed before merging. The relevant information should be in the PR description on GitHub, not in committed files.

[Copilot]

These markdown files (PR_DESCRIPTION_*.md, IMPLEMENTATION_COMPLETE.md, CREATE_PR_NOW.md) appear to be development/collaboration documents that were accidentally committed to the repository. These files should be removed before merging as they contain PR meta-information, internal team strategy, bounty discussions, and instructions for creating the PR itself - none of which belong in the actual codebase.

[Copilot]

The parameter name minGix is inconsistent with the query logic. The parameter is named to suggest it's a "global index", but the query actually filters by height >= $minGix. This is confusing because:

1. The parameter name suggests it's filtering by a global_index column
2. The actual implementation filters by the height column
3. The endpoint documentation calls it "minGlobalIndex" but it represents a height value

This should either be renamed to minHeight to accurately reflect what it does, or the query should actually use a global_index column if that's the intended behavior. Looking at the existing streamBlocksDef endpoint in BlocksEndpointDefs.scala, it uses the same minGlobalIndex parameter but the path is "byGlobalIndex", suggesting the codebase treats height as a global index for blocks.

[Copilot]

The comment claims this is an "ALTERNATIVE IMPLEMENTATION APPROACH (different from PR #266)" and extensively compares against PR #266 throughout lines 186-196. However, these implementation details and comparisons to another PR belong in the PR description, not as inline code comments. Code comments should explain why the code does what it does in the context of this codebase, not provide a narrative comparison to alternative implementations in other PRs.

This makes the code harder to maintain because:

1. Future maintainers won't have context about PR Timestamp/globalIndex ordering consistency #266
2. The comparison becomes irrelevant once one approach is merged
3. It clutters the code with historical context that belongs in version control history

Consider removing or significantly condensing this comment to focus only on what this specific implementation does and why, without the comparison to PR #266.

Suggested change

	*
	* ALTERNATIVE IMPLEMENTATION APPROACH (different from PR #266):
	* Instead of using a single recursive CTE, this uses a simpler, more maintainable approach:
	* 1. Use window function ROW_NUMBER() to calculate correct ordering
	* 2. Join with a base calculation to get the starting index
	* 3. Single atomic UPDATE with explicit locking for safety
	*
	* This approach offers:
	* - Better performance on large datasets (no recursion overhead)
	* - Clearer SQL (easier to understand and maintain)
	* - Explicit FOR UPDATE locking for concurrent safety
	* - Compatible with all PostgreSQL versions (no recursive CTE needed)
	*
	*
	* Uses a window function (ROW_NUMBER) to efficiently assign new global indices to affected transactions,
	* starting from the correct base index. The update is performed atomically with explicit locking (FOR UPDATE)
	* to ensure concurrent safety. This approach is compatible with all PostgreSQL versions and avoids recursion.
	*

[Copilot]

These markdown files (PR_DESCRIPTION_*.md, IMPLEMENTATION_COMPLETE.md, CREATE_PR_NOW.md) appear to be development/collaboration documents that were accidentally committed to the repository. These files should be removed before merging as they contain PR meta-information, internal team strategy, bounty discussions, and instructions for creating the PR itself - none of which belong in the actual codebase.

[Copilot]

These markdown files (PR_DESCRIPTION_*.md, IMPLEMENTATION_COMPLETE.md, CREATE_PR_NOW.md) appear to be development/collaboration documents that were accidentally committed to the repository. These files should be removed before merging as they contain PR meta-information, internal team strategy, bounty discussions, and instructions for creating the PR itself - none of which belong in the actual codebase.

Suggested change

	## Summary
	Implements Issue #210: FullBlock streaming API method for explorer-backend.
	Adds a new streaming endpoint that returns complete block data including all transactions, inputs, outputs, and assets.
	---
	## Implementation
	### New Endpoint
	```
	GET /api/v1/blocks/stream/full?minGlobalIndex={gix}&limit={limit}
	```
	**Parameters:**
	- `minGlobalIndex`: Starting height (blocks with height >= this value)
	- `limit`: Maximum number of blocks to return
	**Returns:** Stream of `FullBlockInfo` objects containing:
	- Block header
	- All transactions
	- All inputs
	- All data inputs
	- All outputs
	- All assets
	- Block extension
	- AD proofs
	- Block size
	---
	## Changes Made
	### 1. HeaderQuerySet.scala
	Added SQL query to fetch headers by global index:
	```scala
	def getHeadersAfterGix(minGix: Long, limit: Int): Query0[Header]
	```
	### 2. HeaderRepo.scala
	Added repository method:
	```scala
	def streamHeadersAfterGix(minGix: Long, limit: Int): S[D, Header]
	```
	### 3. Blocks.scala (Service)
	Added streaming service method:
	```scala
	def streamFullBlocks(minGix: Long, limit: Int): Stream[F, FullBlockInfo]
	```
	### 4. BlocksEndpointDefs.scala
	Added endpoint definition:
	```scala
	def streamFullBlocksDef: Endpoint[(Long, Int), ApiErr, fs2.Stream[F, Byte], Fs2Streams[F]]
	```
	### 5. BlocksRoutes.scala
	Added route handler:
	```scala
	private def streamFullBlocksR: HttpRoutes[F]
	```
	---
	## Why This Approach?
	1. **Consistent with existing patterns**: Follows the same structure as `streamBlocks` and `streamBlockSummaries`
	2. **Efficient streaming**: Uses fs2 streams for memory-efficient data transfer
	3. **Reuses existing logic**: Leverages `getFullBlockInfo` method already in the service
	4. **Proper layer separation**: SQL → Repository → Service → Route
	---
	## Usage Example
	```bash
	curl "http://localhost:8080/api/v1/blocks/stream/full?minGlobalIndex=1000000&limit=100"
	```
	Returns a JSON stream of full block data starting from height 1,000,000, limited to 100 blocks.
	---
	**Fixes:** #210

[Copilot]

These markdown files (PR_DESCRIPTION_*.md, IMPLEMENTATION_COMPLETE.md, CREATE_PR_NOW.md) appear to be development/collaboration documents that were accidentally committed to the repository. These files should be removed before merging as they contain PR meta-information, internal team strategy, bounty discussions, and instructions for creating the PR itself - none of which belong in the actual codebase.

Suggested change

	## Summary
	Fixes Issue #259: Blockchain reorganization bug where `global_index` becomes inconsistent with chronological ordering after reorgs.
	⚠️ **DRAFT PR** - Implementation complete, tests pending. Seeking feedback on approach before adding test suite.
	**Problem:** Only `main_chain` flag updates, `global_index` stays wrong → wrong transaction order.
	**Solution:** Recalculate `global_index` using window function with explicit locking.
	---
	## Implementation
	### 1. TransactionQuerySet.scala
	Added `recalculateGlobalIndexFromHeight()` method:
	```scala
	def recalculateGlobalIndexFromHeight(height: Int)(implicit lh: LogHandler): Update0 =
	sql"""
	|WITH base_index AS (
	| SELECT COALESCE(MAX(global_index), -1) AS last_index
	| FROM node_transactions
	| WHERE inclusion_height < $height AND main_chain = true
	|),
	|ordered_txs AS (
	| SELECT
	| t.id, t.header_id,
	| (SELECT last_index FROM base_index) +
	| ROW_NUMBER() OVER (
	| ORDER BY t.inclusion_height ASC,
	| t.timestamp ASC,
	| t.index ASC
	| ) AS new_global_index
	| FROM node_transactions t
	| WHERE t.inclusion_height >= $height AND t.main_chain = true
	| FOR UPDATE
	|)
	|UPDATE node_transactions t
	|SET global_index = o.new_global_index
	|FROM ordered_txs o
	|WHERE t.id = o.id AND t.header_id = o.header_id
	|""".stripMargin.update
	```
	### 2. TransactionRepo.scala
	Added method to trait and implementation:
	```scala
	// Trait
	def recalculateGlobalIndexFromHeight(height: Int): D[Unit]
	// Implementation
	def recalculateGlobalIndexFromHeight(height: Int): D[Unit] =
	QS.recalculateGlobalIndexFromHeight(height).run.void.liftConnectionIO
	```
	### 3. ChainIndexer.scala
	Modified `updateChainStatus()` to trigger recalculation:
	```scala
	private def updateChainStatus(blockId: BlockId, mainChain: Boolean): D[Unit] =
	for {
	_ <- repos.headers.updateChainStatusById(blockId, mainChain)
	_ <- if (settings.indexes.blockStats)
	repos.blocksInfo.updateChainStatusByHeaderId(blockId, mainChain)
	else unit[D]
	_ <- repos.txs.updateChainStatusByHeaderId(blockId, mainChain)
	_ <- repos.outputs.updateChainStatusByHeaderId(blockId, mainChain)
	_ <- repos.inputs.updateChainStatusByHeaderId(blockId, mainChain)
	_ <- repos.dataInputs.updateChainStatusByHeaderId(blockId, mainChain)
	headerOpt <- repos.headers.get(blockId)
	_ <- headerOpt match {
	case Some(header) if mainChain =>
	repos.txs.recalculateGlobalIndexFromHeight(header.height)
	case _ =>
	unit[D]
	}
	} yield ()
	```
	---
	## Why Different from PR #266?
	PR #266 provided test infrastructure only.
	This implementation:
	- Uses window function instead of recursive CTE
	- Explicit `FOR UPDATE` locking
	- Simpler and easier to maintain
	---