refactor exif

* add all exif & IPTC data to files
* create nodes for all exif data

README.md

@@ -45,7 +45,7 @@ The whole [blog](https://kremalicious.com) is a React-based Single Page App buil
 
 ### 🎆 EXIF extraction
 
-Automatically extracts EXIF metadata from my photos on build time. For minimal overhead, [fast-exif](https://github.com/titarenko/fast-exif) parses every JPG file upon Gatsby file node creation and adds the extracted EXIF data as node fields.
+Automatically extracts EXIF & IPTC metadata from my photos on build time. For minimal overhead, [fast-exif](https://github.com/titarenko/fast-exif) & [node-iptc](https://github.com/derekbaron/node-iptc) parse every JPG file upon Gatsby file node creation and add the extracted data as node fields.
 
 This way, EXIF data is only extracted at build time and can be simply queried with GraphQL at run time.
 
@@ -56,7 +56,7 @@ In the end looks like this, including location display with [pigeon-maps](https:
 If you want to know how this works, have a look at the respective component under
 
 - [`src/components/atoms/Exif.jsx`](src/components/atoms/Exif.jsx)
-- the EXIF node fields creation [`gatsby/createExifFields.js`](gatsby/createExifFields.js) running in [`gatsby-node.js`](gatsby-node.js)
+- the EXIF node fields creation [`gatsby/createExif.js`](gatsby/createExif.js) running in [`gatsby-node.js`](gatsby-node.js)
 
 ### 💰 Cryptocurrency donation via Web3/MetaMask
 

gatsby-node.js

@@ -1,6 +1,6 @@
 const webpack = require('webpack')
 const { createMarkdownFields } = require('./gatsby/createMarkdownFields')
-const { createExifFields } = require('./gatsby/createExifFields')
+const { createExif } = require('./gatsby/createExif')
 const {
   generatePostPages,
   generateTagPages,
@@ -9,17 +9,15 @@ const {
 const { generateJsonFeed } = require('./gatsby/feeds')
 const { itemsPerPage } = require('./config')
 
-exports.onCreateNode = ({ node, actions, getNode }) => {
-  const { createNodeField } = actions
-
+exports.onCreateNode = ({ node, actions, getNode, createNodeId }) => {
   // Markdown files
   if (node.internal.type === 'MarkdownRemark') {
-    createMarkdownFields(node, createNodeField, getNode)
+    createMarkdownFields(node, actions, getNode)
   }
 
   // Image files
   if (node.internal.mediaType === 'image/jpeg') {
-    createExifFields(node, createNodeField)
+    createExif(node, actions, createNodeId)
   }
 }
 

gatsby/createExif.js

@@ -0,0 +1,143 @@
+const fs = require('fs')
+const util = require('util')
+const fastExif = require('fast-exif')
+const Fraction = require('fraction.js')
+const getCoordinates = require('dms2dec')
+const iptc = require('node-iptc')
+
+const readFile = util.promisify(fs.readFile)
+
+exports.createExif = async (node, actions, createNodeId) => {
+  try {
+    // exif
+    const exifData = await fastExif.read(node.absolutePath, true)
+    if (!exifData) return
+
+    // iptc
+    const file = await readFile(node.absolutePath)
+    const iptcData = iptc(file)
+
+    createNodes(exifData, iptcData, node, actions, createNodeId)
+  } catch (error) {
+    console.error(`${node.name}: ${error.message}`)
+  }
+}
+
+function createNodes(exifData, iptcData, node, actions, createNodeId) {
+  const { createNodeField, createNode, createParentChildLink } = actions
+  const exifDataFormatted = formatExif(exifData)
+
+  const exif = {
+    ...exifData,
+    iptc: {
+      ...iptcData
+    },
+    formatted: {
+      ...exifDataFormatted
+    }
+  }
+
+  const exifNode = {
+    id: createNodeId(`${node.id} >> ImageExif`),
+    children: [],
+    ...exif,
+    parent: node.id,
+    internal: {
+      contentDigest: `${node.internal.contentDigest}`,
+      type: 'ImageExif'
+    }
+  }
+
+  // add exif fields to existing type file
+  createNodeField({
+    node,
+    name: 'exif',
+    value: exif
+  })
+
+  // create new nodes from all exif data
+  // allowing to be queried with imageExif & AllImageExif
+  createNode(exifNode)
+  createParentChildLink({
+    parent: node,
+    child: exifNode
+  })
+}
+
+function formatExif(exifData) {
+  if (!exifData.exif) return
+
+  const { Model } = exifData.image
+  const {
+    ISO,
+    FNumber,
+    ExposureTime,
+    FocalLength,
+    FocalLengthIn35mmFormat,
+    ExposureBiasValue,
+    ExposureMode,
+    LensModel
+  } = exifData.exif
+
+  const iso = `ISO ${ISO}`
+  const fstop = `ƒ ${FNumber}`
+  const focalLength = `${FocalLengthIn35mmFormat || FocalLength}mm`
+
+  // Shutter speed
+  const { n, d } = new Fraction(ExposureTime)
+  const shutterspeed = `${n}/${d}s`
+
+  // GPS
+  let latitude
+  let longitude
+  if (exifData.gps) ({ latitude, longitude } = formatGps(exifData.gps))
+
+  // Exposure
+  const exposure = formatExposure(ExposureBiasValue || ExposureMode)
+
+  return {
+    iso,
+    model: Model,
+    fstop,
+    shutterspeed,
+    focalLength,
+    lensModel: LensModel,
+    exposure,
+    gps: { latitude, longitude }
+  }
+}
+
+function formatGps(gpsData) {
+  if (!gpsData) return
+
+  const { GPSLatitudeRef, GPSLatitude, GPSLongitudeRef, GPSLongitude } = gpsData
+
+  const GPSdec = getCoordinates(
+    GPSLatitude,
+    GPSLatitudeRef,
+    GPSLongitude,
+    GPSLongitudeRef
+  )
+
+  const latitude = GPSdec[0]
+  const longitude = GPSdec[1]
+
+  return { latitude, longitude }
+}
+
+function formatExposure(exposureMode) {
+  if (!exposureMode) return
+
+  const exposureShortened = parseFloat(exposureMode.toFixed(2))
+  let exposure
+
+  if (exposureMode === 0) {
+    exposure = `+/- ${exposureShortened} ev`
+  } else if (exposureMode > 0) {
+    exposure = `+ ${exposureShortened} ev`
+  } else {
+    exposure = `${exposureShortened} ev`
+  }
+
+  return exposure
+}

gatsby/createExifFields.js

@@ -1,94 +0,0 @@
-const fastExif = require('fast-exif')
-const Fraction = require('fraction.js')
-const dms2dec = require('dms2dec')
-
-exports.createExifFields = async (node, createNodeField) => {
-  let exifData
-  try {
-    exifData = await fastExif.read(node.absolutePath, true)
-    if (!exifData) return
-    constructExifFields(exifData, createNodeField, node)
-  } catch (error) {
-    // console.error(`${node.name}: ${error.message}`)
-    return null // just silently fail when exif can't be extracted
-  }
-}
-
-const getGps = gpsData => {
-  if (!gpsData) return
-
-  const { GPSLatitudeRef, GPSLatitude, GPSLongitudeRef, GPSLongitude } = gpsData
-
-  const GPSdec = dms2dec(
-    GPSLatitude,
-    GPSLatitudeRef,
-    GPSLongitude,
-    GPSLongitudeRef
-  )
-
-  const latitude = GPSdec[0]
-  const longitude = GPSdec[1]
-
-  return { latitude, longitude }
-}
-
-const getExposure = exposureMode => {
-  const exposureShortened = parseFloat(exposureMode.toFixed(2))
-  let exposure
-
-  if (exposureMode === 0) {
-    exposure = `+/- ${exposureShortened} ev`
-  } else if (exposureMode > 0) {
-    exposure = `+ ${exposureShortened} ev`
-  } else {
-    exposure = `${exposureShortened} ev`
-  }
-
-  return exposure
-}
-
-const constructExifFields = (exifData, createNodeField, node) => {
-  const { Model } = exifData.image
-  const {
-    ISO,
-    FNumber,
-    ExposureTime,
-    FocalLength,
-    FocalLengthIn35mmFormat,
-    ExposureBiasValue,
-    ExposureMode,
-    LensModel
-  } = exifData.exif
-
-  const iso = `ISO ${ISO}`
-  const fstop = `ƒ ${FNumber}`
-  const focalLength = `${FocalLengthIn35mmFormat || FocalLength}mm`
-
-  // Shutter speed
-  const { n, d } = new Fraction(ExposureTime)
-  const shutterspeed = `${n}/${d}s`
-
-  // GPS
-  let latitude
-  let longitude
-  if (exifData.gps) ({ latitude, longitude } = getGps(exifData.gps))
-
-  // Exposure
-  const exposure = getExposure(ExposureBiasValue || ExposureMode)
-
-  // add exif fields to type File
-  createNodeField({
-    node,
-    name: 'exif',
-    value: {
-      iso,
-      model: Model,
-      fstop,
-      shutterspeed,
-      focalLength,
-      lensModel: LensModel,
-      exposure,
-      gps: { latitude, longitude }
-    }
-  })
-}

gatsby/createMarkdownFields.js

@@ -2,6 +2,28 @@ const path = require('path')
 const { createFilePath } = require('gatsby-source-filesystem')
 const { repoContentPath } = require('../config')
 
+// Create slug, date & github file link for posts from file path values
+exports.createMarkdownFields = (node, actions, getNode) => {
+  const { createNodeField } = actions
+  const fileNode = getNode(node.parent)
+  const parsedFilePath = path.parse(fileNode.relativePath)
+  const slugOriginal = createFilePath({ node, getNode })
+
+  createSlug(node, createNodeField, slugOriginal, parsedFilePath)
+  createDate(node, createNodeField, slugOriginal)
+
+  // github file link
+  const type = fileNode.sourceInstanceName
+  const file = fileNode.relativePath
+  const githubLink = `${repoContentPath}/${type}/${file}`
+
+  createNodeField({
+    node,
+    name: 'githubLink',
+    value: githubLink
+  })
+}
+
 function createSlug(node, createNodeField, slugOriginal, parsedFilePath) {
   let slug
 
@@ -32,24 +54,3 @@ function createDate(node, createNodeField, slugOriginal) {
     value: date
   })
 }
-
-// Create slug, date & github file link for posts from file path values
-exports.createMarkdownFields = (node, createNodeField, getNode) => {
-  const fileNode = getNode(node.parent)
-  const parsedFilePath = path.parse(fileNode.relativePath)
-  const slugOriginal = createFilePath({ node, getNode })
-
-  createSlug(node, createNodeField, slugOriginal, parsedFilePath)
-  createDate(node, createNodeField, slugOriginal)
-
-  // github file link
-  const type = fileNode.sourceInstanceName
-  const file = fileNode.relativePath
-  const githubLink = `${repoContentPath}/${type}/${file}`
-
-  createNodeField({
-    node,
-    name: 'githubLink',
-    value: githubLink
-  })
-}

src/@types/Image.d.ts

@@ -15,7 +15,7 @@ export interface ImageNode {
   }
 }
 
-export interface Exif {
+export interface ExifFormatted {
   iso: string
   model: string
   fstop: string
@@ -28,3 +28,12 @@ export interface Exif {
     longitude: string
   }
 }
+
+export interface Exif {
+  formatted: ExifFormatted
+  exif: any
+  image: any
+  thumbnail?: any
+  gps?: any
+  iptc?: any
+}

src/components/atoms/Exif.tsx

@@ -4,7 +4,15 @@ import styles from './Exif.module.scss'
 import { Exif as ExifMeta } from '../../@types/Image'
 
 export default function Exif({ exif }: { exif: ExifMeta }) {
-  const { iso, model, fstop, shutterspeed, focalLength, exposure, gps } = exif
+  const {
+    iso,
+    model,
+    fstop,
+    shutterspeed,
+    focalLength,
+    exposure,
+    gps
+  } = exif.formatted
 
   return (
     <aside className={styles.exif}>

src/templates/Post/index.tsx

@@ -79,16 +79,18 @@ export const pageQuery = graphql`
           }
           fields {
             exif {
-              iso
-              model
-              fstop
-              shutterspeed
-              focalLength
-              lensModel
-              exposure
-              gps {
-                latitude
-                longitude
+              formatted {
+                iso
+                model
+                fstop
+                shutterspeed
+                focalLength
+                lensModel
+                exposure
+                gps {
+                  latitude
+                  longitude
+                }
               }
             }
           }