Add api client method for cancel contract, siatest, and moved LoadStr…

…ing method to encoding.go

node/api/client/renter.go

@@ -9,8 +9,18 @@ import (
 
 	"github.com/NebulousLabs/Sia/modules"
 	"github.com/NebulousLabs/Sia/node/api"
+	"github.com/NebulousLabs/Sia/types"
 )
 
+// RenterCancelContractPost uses the /renter/cancel/contract endpoint to cancel
+// a contract
+func (c *Client) RenterCancelContractPost(id types.FileContractID) error {
+	values := url.Values{}
+	values.Set("id", id.String())
+	err := c.post("/renter/cancel/contract", values.Encode(), nil)
+	return err
+}
+
 // RenterContractsGet requests the /renter/contracts resource and returns
 // Contracts and ActiveContracts
 func (c *Client) RenterContractsGet() (rc api.RenterContracts, err error) {

siatest/renter/renter_test.go

@@ -57,6 +57,7 @@ func TestRenter(t *testing.T) {
 		name string
 		test func(*testing.T, *siatest.TestGroup)
 	}{
+		{"TestCancelContract", testCancelContract},
 		{"TestClearDownloadHistory", testClearDownloadHistory},
 		{"TestDownloadAfterRenew", testDownloadAfterRenew},
 		{"TestDownloadMultipleLargeSectors", testDownloadMultipleLargeSectors},
@@ -74,6 +75,54 @@ func TestRenter(t *testing.T) {
 	}
 }
 
+// testCancelContract tests the RenterCancelContract Endpoint
+func testCancelContract(t *testing.T, tg *siatest.TestGroup) {
+	// Grab the first of the group's renters
+	r := tg.Renters()[0]
+
+	// Grab contracts
+	rc, err := r.RenterContractsGet()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Grab contract to cancel
+	contract := rc.ActiveContracts[0]
+
+	// Cancel Contract
+	if err := r.RenterCancelContractPost(contract.ID); err != nil {
+		t.Fatal(err)
+	}
+
+	// Mine block to trigger threadedContractMaintenance
+	m := tg.Miners()[0]
+	if err := m.MineBlock(); err != nil {
+		t.Fatal(err)
+	}
+	tg.Sync()
+
+	// Check that Contract is now in inactive contracts and no longer in Active contracts
+	rc, err = r.RenterInactiveContractsGet()
+	if err != nil {
+		t.Fatal(err)
+	}
+	for _, c := range rc.ActiveContracts {
+		if c.ID == contract.ID {
+			t.Fatal("Contract not cancelled, contract found in Active Contracts")
+		}
+	}
+	i := 1
+	for _, c := range rc.InactiveContracts {
+		if c.ID == contract.ID {
+			break
+		}
+		if i == len(rc.InactiveContracts) {
+			t.Fatal("Contract not found in Inactive Contracts")
+		}
+		i++
+	}
+}
+
 // testClearDownloadHistory makes sure that the download history is
 // properly cleared when called through the API
 func testClearDownloadHistory(t *testing.T, tg *siatest.TestGroup) {

types/encoding.go

@@ -459,6 +459,11 @@ func (fcr *FileContractRevision) UnmarshalSia(r io.Reader) error {
 	return d.Err()
 }
 
+// LoadString loads a FileContractID from a string
+func (fcid *FileContractID) LoadString(str string) error {
+	return (*crypto.Hash)(fcid).LoadString(str)
+}
+
 // MarshalJSON marshals an id as a hex string.
 func (fcid FileContractID) MarshalJSON() ([]byte, error) {
 	return json.Marshal(fcid.String())

types/transactions.go

@@ -149,11 +149,6 @@ type (
 	UnlockHash crypto.Hash
 )
 
-// LoadString loads a FileContractID from a string
-func (fcid *FileContractID) LoadString(str string) error {
-	return (*crypto.Hash)(fcid).LoadString(str)
-}
-
 // ID returns the id of a transaction, which is taken by marshalling all of the
 // fields except for the signatures and taking the hash of the result.
 func (t Transaction) ID() TransactionID {