add feature to dry-run preimage (#179)

src/blockchain/block-builder.ts

@@ -45,7 +45,7 @@ const getNewSlot = (digest: RawBabePreDigest, slotNumber: number) => {
   return digest.toJSON()
 }
 
-const newHeader = async (head: Block) => {
+export const newHeader = async (head: Block) => {
   const meta = await head.meta
   const parentHeader = await head.header
 

src/blockchain/index.ts

@@ -192,4 +192,10 @@ export class Blockchain {
     const inherents = await this.#inherentProvider.createInherents(head, { horizontalMessages: hrmp })
     return dryRunInherents(head, inherents)
   }
+
+  async getInherents(): Promise<HexString[]> {
+    await this.api.isReady
+    const inherents = await this.#inherentProvider.createInherents(this.head)
+    return inherents
+  }
 }

src/cli.ts

@@ -9,6 +9,7 @@ import { Blockchain, BuildBlockMode, connectParachains, connectVertical, setup,
 import { configSchema } from './schema'
 import { decodeKey } from './utils/decoder'
 import { dryRun } from './dry-run'
+import { dryRunPreimage } from './dry-run-preimage'
 import { isUrl } from './utils'
 import { runBlock } from './run-block'
 
@@ -88,12 +89,15 @@ yargs(hideBin(process.argv))
         extrinsic: {
           desc: 'Extrinsic or call to dry run. If you pass call here then address is required to fake signature',
           string: true,
-          required: true,
         },
         address: {
           desc: 'Address to fake sign extrinsic',
           string: true,
         },
+        preimage: {
+          desc: 'Preimage to dry run',
+          string: true,
+        },
         at: {
           desc: 'Block hash to dry run',
           string: true,
@@ -110,7 +114,12 @@ yargs(hideBin(process.argv))
         },
       }),
     async (argv) => {
-      await dryRun(await processArgv(argv))
+      const config = await processArgv(argv)
+      if (config.preimage) {
+        await dryRunPreimage(config)
+      } else {
+        await dryRun(config)
+      }
     }
   )
   .command(

src/dry-run-preimage.ts

@@ -0,0 +1,120 @@
+import { HexString } from '@polkadot/util/types'
+import { blake2AsHex } from '@polkadot/util-crypto'
+import { hexToU8a } from '@polkadot/util'
+
+import { Config } from './schema'
+import { defaultLogger } from './logger'
+import { generateHtmlDiffPreviewFile } from './utils/generate-html-diff'
+import { newHeader } from './blockchain/block-builder'
+import { openHtml } from './utils/open-html'
+import { runTask, taskHandler } from './executor'
+import { setStorage } from './utils/set-storage'
+import { setup } from './setup'
+
+export const dryRunPreimage = async (argv: Config) => {
+  const context = await setup(argv)
+
+  const extrinsic = argv['preimage']
+
+  const block = context.chain.head
+  const registry = await block.registry
+
+  const header = await newHeader(block)
+
+  const data = hexToU8a(extrinsic)
+  const hash = blake2AsHex(data, 256)
+
+  await setStorage(context.chain, {
+    Preimage: {
+      PreimageFor: [[[[hash, data.byteLength]], extrinsic]],
+      StatusFor: [
+        [
+          [hash],
+          {
+            Requested: {
+              count: 1,
+              len: data.byteLength,
+            },
+          },
+        ],
+      ],
+    },
+    Scheduler: {
+      Agenda: [
+        [
+          [block.number + 1],
+          [
+            {
+              maybeId: '0x64656d6f637261633a0000000000000000000000000000000000000000000000',
+              priority: 63,
+              call: {
+                Lookup: {
+                  hash: hash,
+                  len: data.byteLength,
+                },
+              },
+              origin: { system: { Root: null } },
+            },
+          ],
+        ],
+      ],
+      Lookup: [[['0x64656d6f637261633a0000000000000000000000000000000000000000000000'], [block.number + 1, 0]]],
+    },
+  })
+
+  const calls: [string, HexString[]][] = [['Core_initialize_block', [header.toHex()]]]
+
+  for (const inherent of await block.chain.getInherents()) {
+    calls.push(['BlockBuilder_apply_extrinsic', [inherent]])
+  }
+
+  calls.push(['BlockBuilder_finalize_block', []])
+
+  defaultLogger.info({ preimage: registry.createType('Call', data).toHuman() }, 'Dry run preimage')
+
+  const result = await runTask(
+    {
+      wasm: await block.wasm,
+      calls,
+      storage: [],
+      mockSignatureHost: false,
+      allowUnresolvedImports: false,
+    },
+    taskHandler(block)
+  )
+
+  if (result.Error) {
+    throw new Error(result.Error)
+  }
+
+  const filePath = await generateHtmlDiffPreviewFile(block, result.Call.storageDiff, hash)
+  console.log(`Generated preview ${filePath}`)
+  if (argv['open']) {
+    openHtml(filePath)
+  }
+
+  // if dry-run preimage has extrinsic arguments then dry-run extrinsic
+  // this is usefull to test something after preimage is applied
+  if (argv['extrinsic']) {
+    await context.chain.newBlock()
+    const input = argv['address'] ? { call: argv['extrinsic'], address: argv['address'] } : argv['extrinsic']
+    const { outcome, storageDiff } = await context.chain.dryRunExtrinsic(input)
+    if (outcome.isErr) {
+      throw new Error(outcome.asErr.toString())
+    } else {
+      defaultLogger.info(outcome.toHuman(), 'dry_run_outcome')
+    }
+
+    const filePath = await generateHtmlDiffPreviewFile(
+      context.chain.head,
+      storageDiff,
+      blake2AsHex(argv['extrinsic'], 256)
+    )
+    console.log(`Generated preview ${filePath}`)
+    if (argv['open']) {
+      openHtml(filePath)
+    }
+  }
+
+  process.exit(0)
+}

src/utils/set-storage.ts

@@ -38,11 +38,13 @@ function objectToStorageItems(meta: DecoratedMeta, storage: StorageConfig): RawS
 
       if (storageEntry.meta.type.isPlain) {
         const key = new StorageKey(meta.registry, [storageEntry])
-        storageItems.push([key.toHex(), storage ? meta.registry.createType(key.outputType, storage).toHex(true) : null])
+        const type = storageEntry.meta.modifier.isOptional ? `Option<${key.outputType}>` : key.outputType
+        storageItems.push([key.toHex(), storage ? meta.registry.createType(type, storage).toHex() : null])
       } else {
         for (const [keys, value] of storage) {
           const key = new StorageKey(meta.registry, [storageEntry, keys])
-          storageItems.push([key.toHex(), value ? meta.registry.createType(key.outputType, value).toHex(true) : null])
+          const type = storageEntry.meta.modifier.isOptional ? `Option<${key.outputType}>` : key.outputType
+          storageItems.push([key.toHex(), value ? meta.registry.createType(type, value).toHex() : null])
         }
       }
     }