Changes for programmatic usage

README.md

@@ -8,55 +8,95 @@
 
 ### Installation from npm
 
-`npm i @poanet/solidity-flattener`
+```bash
+npm install https://github.com/vulcanize/solidity-flattener.git
+```
 
-### Usage
+#### Usage
 
-`./node_modules/.bin/poa-solidity-flattener ./contracts/example.sol`
+* CLI:
 
-It will save flattened source of Solidity smart-contract into `./out` directory
+  ```bash
+  npm run solidity-flattener [input-file-path] [output-file-path]
+  ```
+
+    * `input-file-path`: Input contract file path.
+    * `output-file-path`: Flattened contract output file path (default: appends `-flat` to input filename).
 
-### Installation from source
+  Arguments are taken from `config.json` if not provided.
+
+  Example:
+
+  ```bash
+  npm run solidity-flattener ./contracts/ERC20/ERC20.sol ./out/ERC20-flat.sol
+  ```
+
+* As a package:
 
+  Example:
+
+  ```
+  const { flatten } = require('@poanet/solidity-flattener')
+
+  const inputFile = './contracts/ERC20/ERC20.sol'
+  const flatContract = flatten(inputFile)
+  console.log(flatContract)
+  ```
+
+### Installation from source
 
 ```
-git clone https://github.com/poanetwork/solidity-flattener
+git clone https://github.com/vulcanize/solidity-flattener
 cd solidity-flattener
 npm install
 ```
 
-You can start script either
+#### Usage
+
+You can start the script with:
 
 ```
-npm start "path_to_not_flat_contract_definition_file.sol"
+npm start [input-file-path] [output-file-path]
 ```
 
-or without paramaters (path to input file will be extracted from `./config.json`)
+  * `input-file-path`: Input contract file path.
+  * `output-file-path`: Flattened contract output file path (default: appends `-flat` to input filename).
+
+Arguments are taken from `config.json` if not provided.
+
+Examples:
 
 ```
-npm start
+# Saves the flattened contract at the provided output-file-path.
+npm start ./contracts/ERC20/ERC20.sol ./out/ERC20-flat.sol
 ```
 
+```
+# Saves the flattened contract at the provided output-file-path in config.json.
+npm start
+```
 
-
-Expected result: 
+If there is no `output-file-path` in `config.json`:
 
 ```
-Success! Flat file ORIGINAL_FILE_NAME_flat.sol is generated to ./out directory
+# Saves the flattened contract at `./Oracles-flat.sol`
+npm start ./demo/src/Oracles.sol
 ```
 
-`./flatContract.sol` - flat .sol file is created in output directory (`./out/` by default)
-
-**Note:** *utility doesn't support aliases at import statements*
+**Note:** *Utility doesn't support aliases at import statements.*
 
 ## Config
 
-path `./config.json`
+* Path: `./config.json`
+* Fields:
+    * `input-file-path`: Input contract file path.
+    * `output-file-path`: Flattened contract output file path.
 
-```
-{
-	"inputFilePath": "./demo/src/Oracles.sol",
-	"outputDir": "./out"
-}
-```
+* Example:
 
+  ```
+  {
+    "inputFilePath": "./demo/src/Oracles.sol",
+    "outputFilePath": "./demo/out/Oracles-flat.sol"
+  }
+  ```

bin/solidity-flattener

@@ -0,0 +1,6 @@
+#! /usr/bin/env node
+
+const { main } = require('../index.js')
+
+const args = process.argv.slice(2)
+main(args)

config.json

@@ -1,4 +1,4 @@
 {
 	"inputFilePath": "./demo/src/Oracles.sol",
-	"outputDir": "./out"
-}
+	"outputFilePath": "./demo/out/Oracles-flat.sol"
+}

helpers/find-file.js

@@ -1,7 +1,7 @@
 const fs = require('fs')
 const glob = require('glob-promise')
 const path = require('path')
-const variables = require('./variables')
+const { processVariables } = require('./variables')
 const constants = require('./constants')
 const changeRelativePathToAbsolute = require('./change-relative-path-to-absolute')
 
@@ -60,7 +60,7 @@ async function byNameAndReplaceInnerRecursivelyInner(importStatement, updatedFil
 
 	let isAbsolutePath = !dependencyPath.startsWith(constants.DOT)
 	const filePath = srcFiles[j]
-	const { importedSrcFiles } = variables
+	const { importedSrcFiles } = processVariables(process.argv.slice(2))
 	if (isAbsolutePath && filePath.includes(dependencyPath)) {
 		let flattenFileContent = constants.EMPTY
 		if (!importedSrcFiles.hasOwnProperty(path.basename(filePath)) || fs.existsSync(dependencyPath)) {

helpers/logger.js

@@ -1,4 +1,9 @@
 let bunyan = require('bunyan')
-let log = bunyan.createLogger({name: 'solidity-flattener'})
 
-module.exports = log
+const level = process.env.DEBUG_LEVEL || 'error'
+let log = bunyan.createLogger({
+	name: 'solidity-flattener',
+	level
+})
+
+module.exports = log

helpers/replace-all-imports-in-current-layer.js

@@ -1,6 +1,6 @@
 const fs = require('fs')
 const path = require('path')
-const variables = require('./variables')
+const { processVariables } = require('./variables')
 const constants = require('./constants')
 const findFile = require('./find-file')
 const updateImportObjectLocationInTarget = require('./update-import-object-location-in-target')
@@ -20,7 +20,7 @@ async function replaceAllImportsInCurrentLayerInner(i, importObjs, updatedFileCo
 	}
 
 	let importObj = importObjs[i]
-	const { importedSrcFiles } = variables
+	const { importedSrcFiles } = processVariables(process.argv.slice(2))
 	let _updatedFileContent
 
 	//replace contracts aliases

helpers/variables.js

@@ -1,39 +1,38 @@
 const path = require('path')
 const fs = require('fs')
+
 const constants = require('./constants')
 
-const configPath = './config.json'
-let configExists = fs.existsSync(configPath, fs.F_OK)
-let config
-if (configExists) {
-	config = JSON.parse(fs.readFileSync(configPath, constants.UTF8))
-}
+function processVariables(args) {
 
-//Input solidity file path
-let args = process.argv.slice(2)
-let inputFilePath = args.length > 0 ? args[0] : config ? config.inputFilePath : constants.EMPTY
+	const configPath = './config.json'
+	let configExists = fs.existsSync(configPath, fs.F_OK)
+	let config
+	if (configExists) {
+		config = JSON.parse(fs.readFileSync(configPath, constants.UTF8))
+	}
 
-//Input solidity file dir name
-let inputFileDir = path.dirname(inputFilePath)
+	// Get file paths. Resolution order: Command line args, config, defaults.
+	const inputFilePath = args.length > 0 ? args[0] : config ? config.inputFilePath : constants.EMPTY
+	const outputFilePath = args.length > 1 ? args[1] : config ? config.outputFilePath : constants.EMPTY
 
-//Input parent dir
-let parentDir = inputFileDir
+	// Output directory to store flat combined solidity file.
+	const outputDir = path.dirname(outputFilePath)
 
-//Output directory to store flat combined solidity file
-let outDir = args.length > 1 ? args[1] : config ? config.outputDir : './out'
-let flatContractPrefix = args.length > 2 ? args[2] : path.basename(inputFilePath, '.sol')
+	// Extracting filename for output file if outputFilePath not given.
+	const flatContractPrefix = path.basename(inputFilePath, '.sol')
 
-let allSrcFiles = []
-let importedSrcFiles = {}
+	const importedSrcFiles = {}
 
+	const variables = {
+		inputFilePath,
+		outputFilePath,
+		outputDir,
+		importedSrcFiles,
+		flatContractPrefix
+	}
+
+	return variables
+}
 
-module.exports = {
-	args,
-	inputFilePath,
-	inputFileDir,
-	parentDir,
-	outDir,
-	allSrcFiles,
-	importedSrcFiles,
-	flatContractPrefix
-}
+module.exports = { processVariables }

index.js

@@ -1,35 +1,41 @@
 #! /usr/bin/env node
+
+const path = require('path')
 const fs = require('fs')
-const glob = require('glob-promise')
-const variables = require('./helpers/variables')
+
+const { processVariables } = require('./helpers/variables')
 const log = require('./helpers/logger')
 const constants = require('./helpers/constants')
-const cleanPath = require('./helpers/clean-path')
 const replaceAllImportsRecursively = require('./helpers/replace-all-imports-recursively')
 const {
 	deduplicateSolidityVersoins,
 	deduplicateSolidityExpHeaders,
 	deduplicateLicenses
 } = require('./helpers/deduplicate-lines')
 
-flatten()
-
-async function flatten() {
-	const inputFileContent = await fs.readFileSync(variables.inputFilePath, 'utf8')
-	let dir = variables.parentDir + constants.SLASH
-	const isAbsolutePath = !dir.startsWith(constants.DOT)
-	if (!isAbsolutePath) {
-		dir = __dirname + constants.SLASH + dir
-	}
-	dir = cleanPath(dir)
-	const path = variables.parentDir + constants.SOL
-	const srcFiles = await getSourceFiles(dir, path)
-	variables.srcFiles = srcFiles
-	await replaceImports(inputFileContent, dir)
+async function main(args) {
+	// Get the processed variables.
+	const variables = processVariables(args)
+
+	// Flatten the contract.
+	const outputFileContent = await flatten(variables.inputFilePath)
+
+	// Store the output file at the required destination.
+	if (!fs.existsSync(variables.outputDir)) fs.mkdirSync(variables.outputDir, { recursive: true })
+	const fileName = variables.outputFilePath ? path.basename(variables.outputFilePath) : `${variables.flatContractPrefix}-flat.sol`
+	const filePath = `${variables.outputDir}/${fileName}`
+	fs.writeFileSync(filePath, outputFileContent)
+	log.info(`Success! Flat file ${fileName} is generated to  ${variables.outputDir} directory.`)
 }
 
-async function getSourceFiles(dir, path) {
-	return await glob(path)
+async function flatten(inputFilePath) {
+	inputFilePath = path.resolve(inputFilePath)
+
+	const inputFileContent = fs.readFileSync(inputFilePath, 'utf8')
+
+	let dir = path.dirname(inputFilePath) + constants.SLASH
+
+	return await replaceImports(inputFileContent, dir)
 }
 
 async function replaceImports(inputFileContent, dir) {
@@ -39,9 +45,7 @@ async function replaceImports(inputFileContent, dir) {
 	outputFileContent = deduplicateSolidityVersoins(outputFileContent)
 	outputFileContent = deduplicateSolidityExpHeaders(outputFileContent)
 
-	if (!fs.existsSync(variables.outDir)) fs.mkdirSync(variables.outDir)
-	const fileName = `${variables.flatContractPrefix}_flat.sol`
-	const filePath = `${variables.outDir}/${fileName}`
-	fs.writeFileSync(filePath, outputFileContent)
-	log.info(`Success! Flat file ${fileName} is generated to  ${variables.outDir} directory`)
+	return outputFileContent
 }
+
+module.exports = { flatten, main }