remove hyphen in module name

x/colinearcore/memdb/README.md

@@ -0,0 +1,18 @@
+# MemDB
+
+## Bidding Flow
+
+```mermaid
+flowchart 
+
+s[Submit Bid] --> rdb{{Read MemBids}} --> h{Is Highest Bid?} 
+
+h -- Yes --> m{{Add to MemBids}}
+h -- No --> re1[[Error]]
+
+m -- Every Block --> ae{Auction expired?}
+ae -- Yes --> fh{{Find Highest Bid}}
+ae -- No --> ca{{Check again}} -- Next block --> ae
+
+fh -- Settle --> scs[(Chain State)]
+```

x/colinearcore/memdb/biddb.go

@@ -0,0 +1,176 @@
+package memdb
+
+import (
+	"bytes"
+	"colinear/x/colinearcore/types"
+	"encoding/gob"
+	"errors"
+	"log"
+	"math/big"
+
+	badger "github.com/dgraph-io/badger/v3"
+)
+
+type bidDB struct {
+	db *badger.DB
+}
+
+var BidDB bidDB
+
+// Mount Db & initialize encoder/decoder
+func (b *bidDB) Mount() {
+	db, err := badger.Open(badger.DefaultOptions("").WithInMemory(true))
+	if err != nil {
+		// must force crash here, since db is absolutely required
+		log.Fatalf("Failed to mount in-memory db: %s", err)
+	}
+	b.db = db
+
+	// initialize encode/decode stuff
+	gob.Register([]types.Bid{})
+}
+
+// Add a bid to the bid list under specified auction key.
+func (b *bidDB) AddBid(auctionId string, bid *types.Bid) error {
+	k := []byte(auctionId)
+
+	err := b.db.Update(func(txn *badger.Txn) error {
+		var bids []*types.Bid
+		bidsOld, err := txn.Get(k)
+		if errors.Is(err, badger.ErrKeyNotFound) {
+			// key not found -> just create a new Bid array
+			bids = []*types.Bid{}
+		} else {
+			if err != nil {
+				return err
+			}
+			// key found -> decode contents to bids
+			bidsOld.Value(func(val []byte) error {
+				dec := gob.NewDecoder(bytes.NewReader(val))
+				if err := dec.Decode(&bids); err != nil {
+					return err
+				}
+				return nil
+			})
+		}
+
+		// append bid
+		bids = append(bids, bid)
+		// encode new list
+		buf := bytes.NewBuffer(nil)
+		enc := gob.NewEncoder(buf)
+		if err := enc.Encode(&bids); err != nil {
+			return err
+		}
+		// set under auction key in db
+		if err := txn.Set(k, buf.Bytes()); err != nil {
+			return err
+		}
+
+		return nil
+	})
+
+	return err
+}
+
+// Get the highest bid in the list under specified auction key.
+func (b *bidDB) GetLowestBid(auctionId string) (*types.Bid, error) {
+	k := []byte(auctionId)
+
+	var bid *types.Bid
+
+	err := b.db.View(func(txn *badger.Txn) error {
+		bidData, err := txn.Get(k)
+		if err != nil {
+			if !errors.Is(err, badger.ErrKeyNotFound) {
+				return err
+			} else {
+				return nil
+			}
+		}
+
+		err = bidData.Value(func(val []byte) error {
+			var bids []*types.Bid
+			dec := gob.NewDecoder(bytes.NewReader(val))
+			if err := dec.Decode(&bids); err != nil {
+				return err
+			}
+
+			if bids == nil {
+				return nil
+			}
+
+			minAmt := big.NewInt(0)
+			refAmt := big.NewInt(0)
+			for _, currBid := range bids {
+				if bid == nil {
+					bid = currBid
+					minAmt.SetString(currBid.Amount, 10)
+				} else {
+					// set ref amt.
+					refAmt.SetString(currBid.Amount, 10)
+					// if ref amt is less, then we have a new min
+					if refAmt.Cmp(minAmt) == -1 {
+						bid = currBid
+					}
+				}
+			}
+			return nil
+		})
+
+		return err
+	})
+
+	return bid, err
+}
+
+func (b *bidDB) GetBids(auctionId string) ([]*types.Bid, error) {
+	k := []byte(auctionId)
+
+	var bids []*types.Bid
+	err := b.db.View(func(txn *badger.Txn) error {
+		res, err := txn.Get(k)
+		if err != nil {
+			return err
+		} else {
+			err := res.Value(func(val []byte) error {
+				dec := gob.NewDecoder(bytes.NewReader(val))
+				err := dec.Decode(&bids)
+				return err
+			})
+			return err
+		}
+	})
+
+	return bids, err
+}
+
+func (b *bidDB) ClearAuction(auctionId string) error {
+	k := []byte(auctionId)
+
+	err := b.db.Update(func(txn *badger.Txn) error {
+		return txn.Delete(k)
+	})
+
+	return err
+}
+
+// Iterate over all auction keys in memory. VIEW-ONLY.
+func (b *bidDB) ForEachAuction(viewFunc func(string) error) error {
+	err := b.db.View(func(txn *badger.Txn) error {
+		opts := badger.DefaultIteratorOptions
+		// can customize options down here if we want
+		iter := txn.NewIterator(opts)
+		defer iter.Close()
+		for iter.Rewind(); iter.Valid(); iter.Next() {
+			item := iter.Item()
+			key := string(item.Key())
+			err := viewFunc(key)
+			if err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+	return err
+}

x/colinearcore/memdb/biddb_test.go

@@ -0,0 +1,60 @@
+package memdb
+
+import (
+	"colinear/x/colinearcore/types"
+	"fmt"
+	"testing"
+
+	"github.com/dgraph-io/badger/v3"
+)
+
+func TestBasicFlow(t *testing.T) {
+	// this should panic if there's a problem
+	BidDB.Mount()
+
+	// add a bid
+	if err := BidDB.AddBid("0", &types.Bid{Owner: "cosmos123", Amount: "100"}); err != nil {
+		panic(err)
+	}
+
+	// add a higher bid (db funcs won't check amount, though)
+	if err := BidDB.AddBid("0", &types.Bid{Owner: "cosmos456", Amount: "200"}); err != nil {
+		panic(err)
+	}
+
+	// get all bids out
+	if bids, err := BidDB.GetBids("0"); err != nil {
+		panic(err)
+	} else {
+		if bids == nil {
+			panic("GetBids(0) should should not return nil")
+		}
+		if len(bids) != 2 {
+			panic(fmt.Sprintf("Length of GetBids(0) should be 2, instead got %d", len(bids)))
+		}
+	}
+
+	// check lowest bid
+	if bid, err := BidDB.GetLowestBid("0"); err != nil {
+		panic(err)
+	} else {
+		if bid.Owner != "cosmos123" || bid.Amount != "100" {
+			panic(fmt.Sprintf("Lowest auction item not selected. Amount %s with owner %s was chosen.", bid.Amount, bid.Owner))
+		}
+	}
+
+	// clear auction under id 0
+	if err := BidDB.ClearAuction("0"); err != nil {
+		panic(err)
+	} else {
+		// expect auction key to be unknown
+		if err := BidDB.db.View(func(txn *badger.Txn) error {
+			_, err := txn.Get([]byte("0"))
+			return err
+		}); err != nil {
+			if err != badger.ErrKeyNotFound {
+				panic(err)
+			}
+		}
+	}
+}