Merge pull request #232 from thewtex/writeLocalFile

feat(writeLocalFile): Initial addition

Author: thewtex

src/writeLocalFile.js

@@ -0,0 +1,46 @@
+const path = require('path')
+
+const getFileExtension = require('./getFileExtension.js')
+const extensionToMeshIO = require('./extensionToMeshIO.js')
+
+const writeImageLocalFile = require('./writeImageLocalFile.js')
+const writeMeshLocalFileSync = require('./writeMeshLocalFileSync.js')
+
+/**
+ * Write an image or mesh to a file on the local filesystem in Node.js.
+ *
+ * @param: useCompression compression the pixel data when possible
+ * @param: imageOrMesh itk.Image or itk.Mesh instance to write
+ * @param: filePath path to the file on the local filesystem.
+ *
+ * @return empty Promise
+ */
+const writeLocalFile = (useCompression, imageOrMesh, filePath) => {
+  const absoluteFilePath = path.resolve(filePath)
+  const extension = getFileExtension(absoluteFilePath)
+
+  return new Promise(function (resolve, reject) {
+    try {
+      const isMesh = extensionToMeshIO.hasOwnProperty(extension)
+      if (isMesh) {
+        try {
+          writeMeshLocalFileSync(useCompression, imageOrMesh, filePath)
+          resolve(null)
+        } catch (err) {
+          // Was a .vtk image file? Continue to write as an image.
+          writeImageLocalFile(useCompression, imageOrMesh, filePath).then(() => {
+            resolve(null)
+          })
+        }
+      } else {
+        writeImageLocalFile(useCompression, imageOrMesh, filePath).then(() => {
+          resolve(null)
+        })
+      }
+    } catch (err) {
+      reject(err)
+    }
+  })
+}
+
+module.exports = writeLocalFile

test/writeLocalFileTest.js

@@ -0,0 +1,67 @@
+import test from 'ava'
+import path from 'path'
+
+const IntTypes = require(path.resolve(__dirname, '..', 'dist', 'IntTypes.js'))
+const FloatTypes = require(path.resolve(__dirname, '..', 'dist', 'FloatTypes.js'))
+const PixelTypes = require(path.resolve(__dirname, '..', 'dist', 'PixelTypes.js'))
+const readImageLocalFile = require(path.resolve(__dirname, '..', 'dist', 'readImageLocalFile.js'))
+const readMeshLocalFile = require(path.resolve(__dirname, '..', 'dist', 'readMeshLocalFile.js'))
+const writeLocalFile = require(path.resolve(__dirname, '..', 'dist', 'writeLocalFile.js'))
+
+const testImageInputFilePath = path.resolve(__dirname, '..', 'build', 'ExternalData', 'test', 'Input', 'cthead1.png')
+const testImageOutputFilePath = path.resolve(__dirname, '..', 'build', 'Testing', 'Temporary', 'writeLocalFileTest-cthead1.png')
+const testMeshInputFilePath = path.resolve(__dirname, '..', 'build', 'ExternalData', 'test', 'Input', 'cow.vtk')
+const testMeshOutputFilePath = path.resolve(__dirname, '..', 'build', 'Testing', 'Temporary', 'writeLocalFileTest-cow.vtk')
+
+const verifyImage = (t, image) => {
+  t.is(image.imageType.dimension, 2, 'dimension')
+  t.is(image.imageType.componentType, IntTypes.UInt8, 'componentType')
+  t.is(image.imageType.pixelType, PixelTypes.RGB, 'pixelType')
+  t.is(image.imageType.components, 3, 'components')
+  t.is(image.origin[0], 0.0, 'origin[0]')
+  t.is(image.origin[1], 0.0, 'origin[1]')
+  t.is(image.spacing[0], 1.0, 'spacing[0]')
+  t.is(image.spacing[1], 1.0, 'spacing[1]')
+  t.is(image.direction.getElement(0, 0), 1.0, 'direction (0, 0)')
+  t.is(image.direction.getElement(0, 1), 0.0, 'direction (0, 1)')
+  t.is(image.direction.getElement(1, 0), 0.0, 'direction (1, 0)')
+  t.is(image.direction.getElement(1, 1), 1.0, 'direction (1, 1)')
+  t.is(image.size[0], 256, 'size[0]')
+  t.is(image.size[1], 256, 'size[1]')
+  t.is(image.data.length, 196608, 'data.length')
+}
+
+test('writeLocalFile writes an image file path on the local filesystem', t => {
+  return readImageLocalFile(testImageInputFilePath)
+    .then(function (image) {
+      const useCompression = false
+      return writeLocalFile(useCompression, image, testImageOutputFilePath)
+    })
+    .then(function () {
+      return readImageLocalFile(testImageOutputFilePath).then(function (image) {
+        verifyImage(t, image)
+      })
+    })
+})
+
+const verifyMesh = (t, mesh) => {
+  t.is(mesh.meshType.dimension, 3)
+  t.is(mesh.meshType.pointComponentType, FloatTypes.Float32)
+  t.is(mesh.meshType.cellComponentType, IntTypes.UInt32)
+  t.is(mesh.meshType.pointPixelType, 1)
+  t.is(mesh.meshType.cellPixelType, 1)
+  t.is(mesh.numberOfPoints, 2903)
+  t.is(mesh.numberOfCells, 3263)
+}
+
+test('writeLocalFile writes a mesh file path on the local filesystem', (t) => {
+  return readMeshLocalFile(testMeshInputFilePath)
+    .then(function (mesh) {
+      return writeLocalFile(false, mesh, testMeshOutputFilePath)
+    })
+    .then(function () {
+      return readMeshLocalFile(testMeshOutputFilePath).then(function (mesh) {
+        verifyMesh(t, mesh)
+      })
+    })
+})