feat: page cache + save/load logic + db fixes

client/components/admin/admin-utilities.vue

@@ -6,8 +6,9 @@
       .subheading.grey--text Maintenance and troubleshooting tools
     v-tabs(:color='$vuetify.dark ? "primary" : "grey lighten-4"', fixed-tabs, :slider-color='$vuetify.dark ? "white" : "primary"', show-arrows)
       v-tab(key='tools') Tools
+      v-tab(key='cache') Cache
       v-tab(key='telemetry') Telemetry
-      v-tab(key='telemetry') Support
+      v-tab(key='support') Support
 
       v-tab-item(key='tools', :transition='false', :reverse-transition='false')
         v-container(fluid, grid-list-lg, :class='$vuetify.dark ? "" : "grey lighten-5"')

server/controllers/common.js

@@ -34,7 +34,7 @@ router.get('/*', async (req, res, next) => {
     path: pageArgs.path,
     locale: pageArgs.locale,
     userId: req.user.id,
-    private: false
+    isPrivate: false
   })
   if (page) {
     res.render('page', { page })

server/db/migrations/2.0.0.js

@@ -5,6 +5,7 @@ exports.up = knex => {
     // =====================================
     // ASSETS ------------------------------
     .createTable('assets', table => {
+      table.charset('utf8mb4')
       table.increments('id').primary()
       table.string('filename').notNullable()
       table.string('basename').notNullable()
@@ -18,6 +19,7 @@ exports.up = knex => {
     })
     // ASSET FOLDERS -----------------------
     .createTable('assetFolders', table => {
+      table.charset('utf8mb4')
       table.increments('id').primary()
       table.string('name').notNullable()
       table.string('slug').notNullable()
@@ -25,6 +27,7 @@ exports.up = knex => {
     })
     // AUTHENTICATION ----------------------
     .createTable('authentication', table => {
+      table.charset('utf8mb4')
       table.string('key').notNullable().primary()
       table.boolean('isEnabled').notNullable().defaultTo(false)
       table.json('config').notNullable()
@@ -34,6 +37,7 @@ exports.up = knex => {
     })
     // COMMENTS ----------------------------
     .createTable('comments', table => {
+      table.charset('utf8mb4')
       table.increments('id').primary()
       table.text('content').notNullable()
       table.string('createdAt').notNullable()
@@ -41,12 +45,14 @@ exports.up = knex => {
     })
     // EDITORS -----------------------------
     .createTable('editors', table => {
+      table.charset('utf8mb4')
       table.string('key').notNullable().primary()
       table.boolean('isEnabled').notNullable().defaultTo(false)
       table.json('config').notNullable()
     })
     // GROUPS ------------------------------
     .createTable('groups', table => {
+      table.charset('utf8mb4')
       table.increments('id').primary()
       table.string('name').notNullable()
       table.string('createdAt').notNullable()
@@ -54,6 +60,7 @@ exports.up = knex => {
     })
     // LOCALES -----------------------------
     .createTable('locales', table => {
+      table.charset('utf8mb4')
       table.string('code', 2).notNullable().primary()
       table.json('strings')
       table.boolean('isRTL').notNullable().defaultTo(false)
@@ -64,6 +71,7 @@ exports.up = knex => {
     })
     // LOGGING ----------------------------
     .createTable('loggers', table => {
+      table.charset('utf8mb4')
       table.string('key').notNullable().primary()
       table.boolean('isEnabled').notNullable().defaultTo(false)
       table.string('level').notNullable().defaultTo('warn')
@@ -71,8 +79,10 @@ exports.up = knex => {
     })
     // PAGE HISTORY ------------------------
     .createTable('pageHistory', table => {
+      table.charset('utf8mb4')
       table.increments('id').primary()
       table.string('path').notNullable()
+      table.string('hash').notNullable()
       table.string('title').notNullable()
       table.string('description')
       table.boolean('isPrivate').notNullable().defaultTo(false)
@@ -85,8 +95,10 @@ exports.up = knex => {
     })
     // PAGES -------------------------------
     .createTable('pages', table => {
+      table.charset('utf8mb4')
       table.increments('id').primary()
       table.string('path').notNullable()
+      table.string('hash').notNullable()
       table.string('title').notNullable()
       table.string('description')
       table.boolean('isPrivate').notNullable().defaultTo(false)
@@ -102,24 +114,28 @@ exports.up = knex => {
     })
     // RENDERERS ---------------------------
     .createTable('renderers', table => {
+      table.charset('utf8mb4')
       table.string('key').notNullable().primary()
       table.boolean('isEnabled').notNullable().defaultTo(false)
       table.json('config')
     })
     // SEARCH ------------------------------
     .createTable('searchEngines', table => {
+      table.charset('utf8mb4')
       table.string('key').notNullable().primary()
       table.boolean('isEnabled').notNullable().defaultTo(false)
       table.json('config')
     })
     // SETTINGS ----------------------------
     .createTable('settings', table => {
+      table.charset('utf8mb4')
       table.string('key').notNullable().primary()
       table.json('value')
       table.string('updatedAt').notNullable()
     })
     // STORAGE -----------------------------
     .createTable('storage', table => {
+      table.charset('utf8mb4')
       table.string('key').notNullable().primary()
       table.boolean('isEnabled').notNullable().defaultTo(false)
       table.string('mode', ['sync', 'push', 'pull']).notNullable().defaultTo('push')
@@ -127,6 +143,7 @@ exports.up = knex => {
     })
     // TAGS --------------------------------
     .createTable('tags', table => {
+      table.charset('utf8mb4')
       table.increments('id').primary()
       table.string('tag').notNullable().unique()
       table.string('title')
@@ -135,6 +152,7 @@ exports.up = knex => {
     })
     // USERS -------------------------------
     .createTable('users', table => {
+      table.charset('utf8mb4')
       table.increments('id').primary()
       table.string('email').notNullable()
       table.string('name').notNullable()
@@ -155,18 +173,21 @@ exports.up = knex => {
     // =====================================
     // PAGE HISTORY TAGS ---------------------------
     .createTable('pageHistoryTags', table => {
+      table.charset('utf8mb4')
       table.increments('id').primary()
       table.integer('pageId').unsigned().references('id').inTable('pageHistory').onDelete('CASCADE')
       table.integer('tagId').unsigned().references('id').inTable('tags').onDelete('CASCADE')
     })
     // PAGE TAGS ---------------------------
     .createTable('pageTags', table => {
+      table.charset('utf8mb4')
       table.increments('id').primary()
       table.integer('pageId').unsigned().references('id').inTable('pages').onDelete('CASCADE')
       table.integer('tagId').unsigned().references('id').inTable('tags').onDelete('CASCADE')
     })
     // USER GROUPS -------------------------
     .createTable('userGroups', table => {
+      table.charset('utf8mb4')
       table.increments('id').primary()
       table.integer('userId').unsigned().references('id').inTable('users').onDelete('CASCADE')
       table.integer('groupId').unsigned().references('id').inTable('groups').onDelete('CASCADE')

server/helpers/page.js

@@ -1,5 +1,6 @@
 const qs = require('querystring')
 const _ = require('lodash')
+const crypto = require('crypto')
 
 module.exports = {
   /**
@@ -26,5 +27,11 @@ module.exports = {
     }
     pathObj.path = _.join(pathParts, '/')
     return pathObj
+  },
+  /**
+   * Generate unique hash from page
+   */
+  generateHash(opts) {
+    return crypto.createHash('sha1').update(`${opts.locale}|${opts.path}|${opts.privateNS}`).digest('hex')
   }
 }

server/jobs/render-page.js

@@ -20,7 +20,17 @@ module.exports = async (job) => {
         input: output
       })
     }
-    console.info(output)
+
+    // Save to DB
+    await WIKI.models.pages.query()
+      .patch({ render: output })
+      .where('id', job.data.page.id)
+
+    // Save to cache
+    await WIKI.models.pages.savePageToCache({
+      ...job.data.page,
+      render: output
+    })
 
     WIKI.logger.info(`Rendering page ${job.data.page.path}: [ COMPLETED ]`)
   } catch (err) {

server/models/pageHistory.js

@@ -16,6 +16,7 @@ module.exports = class PageHistory extends Model {
       properties: {
         id: {type: 'integer'},
         path: {type: 'string'},
+        hash: {type: 'string'},
         title: {type: 'string'},
         description: {type: 'string'},
         isPublished: {type: 'boolean'},
@@ -88,6 +89,7 @@ module.exports = class PageHistory extends Model {
       content: opts.content,
       description: opts.description,
       editorKey: opts.editorKey,
+      hash: opts.hash,
       isPrivate: opts.isPrivate,
       isPublished: opts.isPublished,
       localeCode: opts.localeCode,

server/models/pages.js

@@ -1,5 +1,9 @@
 const Model = require('objection').Model
 const _ = require('lodash')
+const JSBinType = require('js-binary').Type
+const pageHelper = require('../helpers/page')
+const path = require('path')
+const fs = require('fs-extra')
 
 /* global WIKI */
 
@@ -17,6 +21,7 @@ module.exports = class Page extends Model {
       properties: {
         id: {type: 'integer'},
         path: {type: 'string'},
+        hash: {type: 'string'},
         title: {type: 'string'},
         description: {type: 'string'},
         isPublished: {type: 'boolean'},
@@ -89,35 +94,33 @@ module.exports = class Page extends Model {
     this.updatedAt = new Date().toISOString()
   }
 
-  static async getPage(opts) {
-    const page = await WIKI.models.pages.query().where({
-      path: opts.path,
-      localeCode: opts.locale
-    }).andWhere(builder => {
-      builder.where({
-        isPublished: true
-      }).orWhere({
-        isPublished: false,
-        authorId: opts.userId
-      })
-    }).andWhere(builder => {
-      if (opts.private) {
-        builder.where({ isPrivate: true, privateNS: opts.privateNS })
-      } else {
-        builder.where({ isPrivate: false })
-      }
-    }).first()
-    return page
+  static get cacheSchema() {
+    return new JSBinType({
+      authorId: 'uint',
+      authorName: 'string',
+      createdAt: 'string',
+      creatorId: 'uint',
+      creatorName: 'string',
+      description: 'string',
+      isPrivate: 'boolean',
+      isPublished: 'boolean',
+      publishEndDate: 'string',
+      publishStartDate: 'string',
+      render: 'string',
+      title: 'string',
+      updatedAt: 'string'
+    })
   }
 
   static async createPage(opts) {
-    const page = await WIKI.models.pages.query().insertAndFetch({
+    await WIKI.models.pages.query().insert({
       authorId: opts.authorId,
       content: opts.content,
       creatorId: opts.authorId,
       contentType: _.get(_.find(WIKI.data.editors, ['key', opts.editor]), `contentType`, 'text'),
       description: opts.description,
       editorKey: opts.editor,
+      hash: pageHelper.generateHash({ path: opts.path, locale: opts.locale, privateNS: opts.isPrivate ? 'TODO' : '' }),
       isPrivate: opts.isPrivate,
       isPublished: opts.isPublished,
       localeCode: opts.locale,
@@ -126,6 +129,7 @@ module.exports = class Page extends Model {
       publishStartDate: opts.publishStartDate,
       title: opts.title
     })
+    const page = await WIKI.models.pages.getPageFromDb(opts)
     await WIKI.models.pages.renderPage(page)
     await WIKI.models.storage.pageEvent({
       event: 'created',
@@ -140,7 +144,7 @@ module.exports = class Page extends Model {
       throw new Error('Invalid Page Id')
     }
     await WIKI.models.pageHistory.addVersion(ogPage)
-    const page = await WIKI.models.pages.query().patchAndFetchById(ogPage.id, {
+    await WIKI.models.pages.query().patch({
       authorId: opts.authorId,
       content: opts.content,
       description: opts.description,
@@ -148,7 +152,8 @@ module.exports = class Page extends Model {
       publishEndDate: opts.publishEndDate,
       publishStartDate: opts.publishStartDate,
       title: opts.title
-    })
+    }).where('id', ogPage.id)
+    const page = await WIKI.models.pages.getPageFromDb(opts)
     await WIKI.models.pages.renderPage(page)
     await WIKI.models.storage.pageEvent({
       event: 'updated',
@@ -167,4 +172,88 @@ module.exports = class Page extends Model {
       removeOnFail: true
     })
   }
+
+  static async getPage(opts) {
+    let page = await WIKI.models.pages.getPageFromCache(opts)
+    if (!page) {
+      page = await WIKI.models.pages.getPageFromDb(opts)
+      await WIKI.models.pages.savePageToCache(page)
+    }
+    return page
+  }
+
+  static async getPageFromDb(opts) {
+    const page = await WIKI.models.pages.query()
+      .column([
+        'pages.*',
+        {
+          authorName: 'author.name',
+          creatorName: 'creator.name'
+        }
+      ])
+      .joinRelation('author')
+      .joinRelation('creator')
+      .where({
+        'pages.path': opts.path,
+        'pages.localeCode': opts.locale
+      })
+      .andWhere(builder => {
+        builder.where({
+          'pages.isPublished': true
+        }).orWhere({
+          'pages.isPublished': false,
+          'pages.authorId': opts.userId
+        })
+      })
+      .andWhere(builder => {
+        if (opts.isPrivate) {
+          builder.where({ 'pages.isPrivate': true, 'pages.privateNS': opts.privateNS })
+        } else {
+          builder.where({ 'pages.isPrivate': false })
+        }
+      })
+      .first()
+    return page
+  }
+
+  static async savePageToCache(page) {
+    const cachePath = path.join(process.cwd(), `data/cache/${page.hash}.bin`)
+    await fs.outputFile(cachePath, WIKI.models.pages.cacheSchema.encode({
+      authorId: page.authorId,
+      authorName: page.authorName,
+      createdAt: page.createdAt,
+      creatorId: page.creatorId,
+      creatorName: page.creatorName,
+      description: page.description,
+      isPrivate: page.isPrivate === 1,
+      isPublished: page.isPublished === 1,
+      publishEndDate: page.publishEndDate,
+      publishStartDate: page.publishStartDate,
+      render: page.render,
+      title: page.title,
+      updatedAt: page.updatedAt
+    }))
+  }
+
+  static async getPageFromCache(opts) {
+    const pageHash = pageHelper.generateHash({ path: opts.path, locale: opts.locale, privateNS: opts.isPrivate ? 'TODO' : '' })
+    const cachePath = path.join(process.cwd(), `data/cache/${pageHash}.bin`)
+
+    try {
+      const pageBuffer = await fs.readFile(cachePath)
+      let page = WIKI.models.pages.cacheSchema.decode(pageBuffer)
+      return {
+        ...page,
+        path: opts.path,
+        localeCode: opts.locale,
+        isPrivate: opts.isPrivate
+      }
+    } catch (err) {
+      if (err.code === 'ENOENT') {
+        return false
+      }
+      WIKI.logger.error(err)
+      throw err
+    }
+  }
 }

server/setup.js

@@ -90,10 +90,10 @@ module.exports = () => {
       }
 
       // Create directory structure
-      const tmpPath = path.join(os.tmpdir(), 'wikijs')
-      await fs.ensureDir(tmpPath)
-      await fs.ensureDir(path.join(tmpPath, 'cache'))
-      await fs.ensureDir(path.join(tmpPath, 'uploads'))
+      const dataPath = path.join(process.cwd(), 'data')
+      await fs.ensureDir(dataPath)
+      await fs.ensureDir(path.join(dataPath, 'cache'))
+      await fs.ensureDir(path.join(dataPath, 'uploads'))
 
       // Set config
       _.set(WIKI.config, 'defaultEditor', 'markdown')

server/views/page.pug

@@ -17,40 +17,3 @@ block body
       is-published=page.isPublished
       )
       template(slot='contents')!= page.render
-        p Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago.[24][25][26] Earth's gravity interacts with other objects in space, especially the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in 365.26 days, a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times.[n 5]
-        p Earth's axis of rotation is tilted with respect to its orbital plane, producing seasons on Earth.[27] The gravitational interaction between Earth and the Moon causes ocean tides, stabilizes Earth's orientation on its axis, and gradually slows its rotation. Earth is the densest planet in the Solar System and the largest of the four terrestrial planets.
-        h1 Introduction
-        p Earth's lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earth's surface is covered with water, mostly by oceans.[29] The remaining 29% is land consisting of continents and islands that together have many lakes, rivers and other sources of water that contribute to the hydrosphere. The majority of Earth's polar regions are covered in ice, including the Antarctic ice sheet and the sea ice of the Arctic ice pack. Earth's interior remains active with a solid iron inner core, a liquid outer core that generates the Earth's magnetic field, and a convecting mantle that drives plate tectonics.
-        p Within the first billion years of Earth's history, life appeared in the oceans and began to affect the Earth's atmosphere and surface, leading to the proliferation of aerobic and anaerobic organisms. Some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earth's distance from the Sun, physical properties, and geological history have allowed life to evolve and thrive.[30][31] In the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species[32] that ever lived on Earth are extinct.[33][34] Estimates of the number of species on Earth today vary widely;[35][36][37] most species have not been described.[38] Over 7.6 billion humans live on Earth and depend on its biosphere and natural resources for their survival.[39] Humans have developed diverse societies and cultures; politically, the world has about 200 sovereign states.
-        p Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago.[24][25][26] Earth's gravity interacts with other objects in space, especially the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in 365.26 days, a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times.[n 5]
-        h1 Cities
-        h2 New York
-        p Earth's axis of rotation is tilted with respect to its orbital plane, producing seasons on Earth.[27] The gravitational interaction between Earth and the Moon causes ocean tides, stabilizes Earth's orientation on its axis, and gradually slows its rotation. Earth is the densest planet in the Solar System and the largest of the four terrestrial planets.
-        h2 Chicago
-        p Earth's lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earth's surface is covered with water, mostly by oceans.[29] The remaining 29% is land consisting of continents and islands that together have many lakes, rivers and other sources of water that contribute to the hydrosphere. The majority of Earth's polar regions are covered in ice, including the Antarctic ice sheet and the sea ice of the Arctic ice pack. Earth's interior remains active with a solid iron inner core, a liquid outer core that generates the Earth's magnetic field, and a convecting mantle that drives plate tectonics.
-        p Within the first billion years of Earth's history, life appeared in the oceans and began to affect the Earth's atmosphere and surface, leading to the proliferation of aerobic and anaerobic organisms. Some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earth's distance from the Sun, physical properties, and geological history have allowed life to evolve and thrive.[30][31] In the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species[32] that ever lived on Earth are extinct.[33][34] Estimates of the number of species on Earth today vary widely;[35][36][37] most species have not been described.[38] Over 7.6 billion humans live on Earth and depend on its biosphere and natural resources for their survival.[39] Humans have developed diverse societies and cultures; politically, the world has about 200 sovereign states.
-        p Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago.[24][25][26] Earth's gravity interacts with other objects in space, especially the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in 365.26 days, a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times.[n 5]
-        p Earth's axis of rotation is tilted with respect to its orbital plane, producing seasons on Earth.[27] The gravitational interaction between Earth and the Moon causes ocean tides, stabilizes Earth's orientation on its axis, and gradually slows its rotation. Earth is the densest planet in the Solar System and the largest of the four terrestrial planets.
-        p Earth's lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earth's surface is covered with water, mostly by oceans.[29] The remaining 29% is land consisting of continents and islands that together have many lakes, rivers and other sources of water that contribute to the hydrosphere. The majority of Earth's polar regions are covered in ice, including the Antarctic ice sheet and the sea ice of the Arctic ice pack. Earth's interior remains active with a solid iron inner core, a liquid outer core that generates the Earth's magnetic field, and a convecting mantle that drives plate tectonics.
-        p Within the first billion years of Earth's history, life appeared in the oceans and began to affect the Earth's atmosphere and surface, leading to the proliferation of aerobic and anaerobic organisms. Some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earth's distance from the Sun, physical properties, and geological history have allowed life to evolve and thrive.[30][31] In the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species[32] that ever lived on Earth are extinct.[33][34] Estimates of the number of species on Earth today vary widely;[35][36][37] most species have not been described.[38] Over 7.6 billion humans live on Earth and depend on its biosphere and natural resources for their survival.[39] Humans have developed diverse societies and cultures; politically, the world has about 200 sovereign states.
-        p Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago.[24][25][26] Earth's gravity interacts with other objects in space, especially the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in 365.26 days, a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times.[n 5]
-        p Earth's axis of rotation is tilted with respect to its orbital plane, producing seasons on Earth.[27] The gravitational interaction between Earth and the Moon causes ocean tides, stabilizes Earth's orientation on its axis, and gradually slows its rotation. Earth is the densest planet in the Solar System and the largest of the four terrestrial planets.
-        p Earth's lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earth's surface is covered with water, mostly by oceans.[29] The remaining 29% is land consisting of continents and islands that together have many lakes, rivers and other sources of water that contribute to the hydrosphere. The majority of Earth's polar regions are covered in ice, including the Antarctic ice sheet and the sea ice of the Arctic ice pack. Earth's interior remains active with a solid iron inner core, a liquid outer core that generates the Earth's magnetic field, and a convecting mantle that drives plate tectonics.
-        p Within the first billion years of Earth's history, life appeared in the oceans and began to affect the Earth's atmosphere and surface, leading to the proliferation of aerobic and anaerobic organisms. Some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earth's distance from the Sun, physical properties, and geological history have allowed life to evolve and thrive.[30][31] In the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species[32] that ever lived on Earth are extinct.[33][34] Estimates of the number of species on Earth today vary widely;[35][36][37] most species have not been described.[38] Over 7.6 billion humans live on Earth and depend on its biosphere and natural resources for their survival.[39] Humans have developed diverse societies and cultures; politically, the world has about 200 sovereign states.
-        p Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago.[24][25][26] Earth's gravity interacts with other objects in space, especially the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in 365.26 days, a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times.[n 5]
-        p Earth's axis of rotation is tilted with respect to its orbital plane, producing seasons on Earth.[27] The gravitational interaction between Earth and the Moon causes ocean tides, stabilizes Earth's orientation on its axis, and gradually slows its rotation. Earth is the densest planet in the Solar System and the largest of the four terrestrial planets.
-        p Earth's lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earth's surface is covered with water, mostly by oceans.[29] The remaining 29% is land consisting of continents and islands that together have many lakes, rivers and other sources of water that contribute to the hydrosphere. The majority of Earth's polar regions are covered in ice, including the Antarctic ice sheet and the sea ice of the Arctic ice pack. Earth's interior remains active with a solid iron inner core, a liquid outer core that generates the Earth's magnetic field, and a convecting mantle that drives plate tectonics.
-        p Within the first billion years of Earth's history, life appeared in the oceans and began to affect the Earth's atmosphere and surface, leading to the proliferation of aerobic and anaerobic organisms. Some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earth's distance from the Sun, physical properties, and geological history have allowed life to evolve and thrive.[30][31] In the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species[32] that ever lived on Earth are extinct.[33][34] Estimates of the number of species on Earth today vary widely;[35][36][37] most species have not been described.[38] Over 7.6 billion humans live on Earth and depend on its biosphere and natural resources for their survival.[39] Humans have developed diverse societies and cultures; politically, the world has about 200 sovereign states.
-        p Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago.[24][25][26] Earth's gravity interacts with other objects in space, especially the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in 365.26 days, a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times.[n 5]
-        p Earth's axis of rotation is tilted with respect to its orbital plane, producing seasons on Earth.[27] The gravitational interaction between Earth and the Moon causes ocean tides, stabilizes Earth's orientation on its axis, and gradually slows its rotation. Earth is the densest planet in the Solar System and the largest of the four terrestrial planets.
-        p Earth's lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earth's surface is covered with water, mostly by oceans.[29] The remaining 29% is land consisting of continents and islands that together have many lakes, rivers and other sources of water that contribute to the hydrosphere. The majority of Earth's polar regions are covered in ice, including the Antarctic ice sheet and the sea ice of the Arctic ice pack. Earth's interior remains active with a solid iron inner core, a liquid outer core that generates the Earth's magnetic field, and a convecting mantle that drives plate tectonics.
-        p Within the first billion years of Earth's history, life appeared in the oceans and began to affect the Earth's atmosphere and surface, leading to the proliferation of aerobic and anaerobic organisms. Some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earth's distance from the Sun, physical properties, and geological history have allowed life to evolve and thrive.[30][31] In the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species[32] that ever lived on Earth are extinct.[33][34] Estimates of the number of species on Earth today vary widely;[35][36][37] most species have not been described.[38] Over 7.6 billion humans live on Earth and depend on its biosphere and natural resources for their survival.[39] Humans have developed diverse societies and cultures; politically, the world has about 200 sovereign states.
-        p Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago.[24][25][26] Earth's gravity interacts with other objects in space, especially the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in 365.26 days, a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times.[n 5]
-        p Earth's axis of rotation is tilted with respect to its orbital plane, producing seasons on Earth.[27] The gravitational interaction between Earth and the Moon causes ocean tides, stabilizes Earth's orientation on its axis, and gradually slows its rotation. Earth is the densest planet in the Solar System and the largest of the four terrestrial planets.
-        p Earth's lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earth's surface is covered with water, mostly by oceans.[29] The remaining 29% is land consisting of continents and islands that together have many lakes, rivers and other sources of water that contribute to the hydrosphere. The majority of Earth's polar regions are covered in ice, including the Antarctic ice sheet and the sea ice of the Arctic ice pack. Earth's interior remains active with a solid iron inner core, a liquid outer core that generates the Earth's magnetic field, and a convecting mantle that drives plate tectonics.
-        p Within the first billion years of Earth's history, life appeared in the oceans and began to affect the Earth's atmosphere and surface, leading to the proliferation of aerobic and anaerobic organisms. Some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earth's distance from the Sun, physical properties, and geological history have allowed life to evolve and thrive.[30][31] In the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species[32] that ever lived on Earth are extinct.[33][34] Estimates of the number of species on Earth today vary widely;[35][36][37] most species have not been described.[38] Over 7.6 billion humans live on Earth and depend on its biosphere and natural resources for their survival.[39] Humans have developed diverse societies and cultures; politically, the world has about 200 sovereign states.
-        p Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other sources of evidence, Earth formed over 4.5 billion years ago.[24][25][26] Earth's gravity interacts with other objects in space, especially the Sun and the Moon, Earth's only natural satellite. Earth revolves around the Sun in 365.26 days, a period known as an Earth year. During this time, Earth rotates about its axis about 366.26 times.[n 5]
-        p Earth's axis of rotation is tilted with respect to its orbital plane, producing seasons on Earth.[27] The gravitational interaction between Earth and the Moon causes ocean tides, stabilizes Earth's orientation on its axis, and gradually slows its rotation. Earth is the densest planet in the Solar System and the largest of the four terrestrial planets.
-        p Earth's lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earth's surface is covered with water, mostly by oceans.[29] The remaining 29% is land consisting of continents and islands that together have many lakes, rivers and other sources of water that contribute to the hydrosphere. The majority of Earth's polar regions are covered in ice, including the Antarctic ice sheet and the sea ice of the Arctic ice pack. Earth's interior remains active with a solid iron inner core, a liquid outer core that generates the Earth's magnetic field, and a convecting mantle that drives plate tectonics.
-        p Within the first billion years of Earth's history, life appeared in the oceans and began to affect the Earth's atmosphere and surface, leading to the proliferation of aerobic and anaerobic organisms. Some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earth's distance from the Sun, physical properties, and geological history have allowed life to evolve and thrive.[30][31] In the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species[32] that ever lived on Earth are extinct.[33][34] Estimates of the number of species on Earth today vary widely;[35][36][37] most species have not been described.[38] Over 7.6 billion humans live on Earth and depend on its biosphere and natural resources for their survival.[39] Humans have developed diverse societies and cultures; politically, the world has about 200 sovereign states.
-