allow updating distribution

Author: loic1

pds/contracts/PDS.cdc

@@ -30,6 +30,10 @@ access(all) contract PDS{
     ///
     access(all) event DistributionCreated(DistId: UInt64, title: String, metadata: {String: String}, state: UInt8)
 
+    /// Emitted when an issuer has updated a distribution.
+    ///
+    access(all) event DistributionUpdated(DistId: UInt64, title: String, metadata: {String: String}, state: UInt8)
+
     /// Emmitted when a distribution manager has updated a distribution state.
     ///
     access(all) event DistributionStateUpdated(DistId: UInt64, state: UInt8)
@@ -45,14 +49,19 @@ access(all) contract PDS{
     /// Struct that defines the details of a Distribution.
     ///
     access(all) struct DistInfo {
-        access(all) let title: String
-        access(all) let metadata: {String: String}
+        access(all) var title: String
+        access(all) var metadata: {String: String}
         access(all) var state: PDS.DistState
 
         access(contract) fun setState(newState: PDS.DistState) {
             self.state = newState
         }
 
+        access(contract) fun update(title: String, metadata: {String: String}) {
+            self.title = title
+            self.metadata = metadata
+        }
+
         /// DistInfo struct initializer.
         ///
         view init(title: String, metadata: {String: String}) {
@@ -209,11 +218,23 @@ access(all) contract PDS{
         }
 
         access(Operate) fun createDist(sharedCap: @SharedCapabilities, title: String, metadata: {String: String}) {
-            assert(title.length > 0, message: "Title must not be empty")
+            pre {
+                title.length > 0: "Title must not be empty"
+            }
             let c = self.cap!.borrow()!
             c.createNewDist(sharedCap: <- sharedCap, title: title, metadata: metadata)
         }
 
+        access(Operate) fun updateDist(distId: UInt64, title: String, metadata: {String: String}) {
+            pre {
+                title.length > 0: "Title must not be empty"
+            }
+            let d = PDS.Distributions.remove(key: distId) ?? panic ("No such distribution")
+            d.update(title: title, metadata: metadata)
+            PDS.Distributions.insert(key: distId, d)
+            emit DistributionUpdated(DistId: distId, title: title, metadata: metadata, state: d.state.rawValue)
+        }
+
         /// PackIssuer resource initializer.
         ///
         view init() {

pds/embed.go

@@ -35,4 +35,6 @@ var (
 	PDSRevealPackNFT []byte
 	//go:embed transactions/pds/create_distribution.cdc
 	PDSCreateDistribution []byte
+	//go:embed transactions/pds/update_distribution.cdc
+	PDSUpdateDistribution []byte
 )

pds/transactions/pds/create_distribution.cdc

@@ -1,17 +1,12 @@
 import PDS from "PDS"
 import PackNFT from "PackNFT"
-import ExampleNFT from "ExampleNFT"
 import IPackNFT from "IPackNFT"
 import NonFungibleToken from "NonFungibleToken"
-import MetadataViews from "MetadataViews"
 
 transaction(nftWithdrawCapPath: StoragePath, title: String, metadata: {String: String}) {
     prepare (issuer: auth(Storage, Capabilities) &Account) {
-        let collectionData = ExampleNFT.resolveContractView(resourceType: nil, viewType: Type<MetadataViews.NFTCollectionData>()) as! MetadataViews.NFTCollectionData?
-            ?? panic("ViewResolver does not resolve NFTCollectionData view")
-
         // get pack issuer reference
-        let i = issuer.storage.borrow<auth(PDS.Operate) &PDS.PackIssuer>(from: PDS.PackIssuerStoragePath)
+        let issuerRef = issuer.storage.borrow<auth(PDS.Operate) &PDS.PackIssuer>(from: PDS.PackIssuerStoragePath)
             ?? panic ("issuer does not have PackIssuer resource")
 
         // get withdraw capability from issuer
@@ -24,7 +19,7 @@ transaction(nftWithdrawCapPath: StoragePath, title: String, metadata: {String: S
         assert(operatorCap.check(), message:  "cannot borrow operator capability")
 
         // create SharedCapabilities resource with withdraw and operator capabilities, and create distribution with it
-        i.createDist(
+        issuerRef.createDist(
             sharedCap: <- PDS.createSharedCapabilities(withdrawCap: withdrawCap, operatorCap: operatorCap),
             title: title,
             metadata: metadata,

pds/transactions/pds/update_distribution.cdc

@@ -0,0 +1,16 @@
+import PDS from "PDS"
+
+transaction (distId: UInt64, title: String, metadata: {String: String}) {
+    prepare(issuer: auth(BorrowValue) &Account) {
+        // get pack issuer reference
+        let issuerRef = issuer.storage.borrow<auth(PDS.Operate) &PDS.PackIssuer>(from: PDS.PackIssuerStoragePath)
+            ?? panic ("issuer does not have PackIssuer resource")
+
+        // update distribution
+        issuerRef.updateDist(
+            distId: distId,
+            title: title,
+            metadata: metadata,
+        )
+    }
+}