Example blocks

Example blocks should have a background colour in the docs theme

Example 1

A short example

Example 1. This is a short one

Lorem Ipsunm

Some text follows the example

Example 2. This is also short

Lorem Ipsunm

And some more text here

Example 2

A longer example

Example 3. A longer example

Let’s assume there exists a procedure called myProc.

This procedure gives the result A and B for a user with EXECUTE PROCEDURE privilege and A, B and C for a user with EXECUTE BOOSTED PROCEDURE privilege.

Now, let’s adapt the privileges in examples 1 to 4 to apply to this procedure and show what is returned. With the privileges from example 1, granted EXECUTE PROCEDURE * and denied EXECUTE BOOSTED PROCEDURE myProc, the myProc procedure returns the result A and B.

With the privileges from example 2, granted EXECUTE BOOSTED PROCEDURE * and denied EXECUTE PROCEDURE myProc, execution of the myProc procedure is not allowed.

With the privileges from example 3, granted EXECUTE BOOSTED PROCEDURE * and denied EXECUTE BOOSTED PROCEDURE myProc, execution of the myProc procedure is not allowed.

With the privileges from example 4, granted EXECUTE PROCEDURE myProc and EXECUTE BOOSTED PROCEDURE * and denied EXECUTE BOOSTED PROCEDURE myProc, the myProc procedure returns the result A and B.

For comparison, when only granted EXECUTE BOOSTED PROCEDURE myProc, the myProc procedure returns the result A, B and C, without needing to be granted the EXECUTE PROCEDURE myProc privilege.

A line of text after the longer example

Run Cypher administrative commands from Cypher Shell on a cluster

For the following examples consider a cluster environment formed by 5 members, 3 Core servers, and 2 Read Replicas:

Example 4. View the members of a cluster

neo4j@neo4j> CALL dbms.cluster.overview();

+------------------------------------------------------------------------------------------------------------------------------------------------------------+
| id        | addresses                                                                    | databases                   | groups |
+------------------------------------------------------------------------------------------------------------------------------------------------------------+
| "8c...3d" | ["bolt://localhost:7683", "http://localhost:7473", "https://localhost:7483"] | {neo4j: "FOLLOWER", system: "FOLLOWER"}         | []     |
| "8f...28" | ["bolt://localhost:7681", "http://localhost:7471", "https://localhost:7481"] | {neo4j: "LEADER", system: "LEADER"}                   | []     |
| "e0...4d" | ["bolt://localhost:7684", "http://localhost:7474", "https://localhost:7484"] | {neo4j: "READ_REPLICA", system: "READ_REPLICA"}     | []     |
| "1a...64" | ["bolt://localhost:7682", "http://localhost:7472", "https://localhost:7482"] | {neo4j: "FOLLOWER", system: "FOLLOWER"}         | []     |
| "59...87" | ["bolt://localhost:7685", "http://localhost:7475", "https://localhost:7485"] | {neo4j: "READ_REPLICA", system: "READ_REPLICA"}     | []     |
+------------------------------------------------------------------------------------------------------------------------------------------------------------+

5 rows available after 5 ms, consumed after another 0 ms

The leader is currently the instance exposing port 7681 for the bolt protocol, and 7471/7481 for the http/https protocol.

Administrators can connect and execute Cypher commands in the following ways:

Example 5. Using the bolt:// scheme to connect to the Leader:

$ bin/cypher-shell -a bolt://localhost:7681 -d system -u neo4j -p neo4j1

Connected to Neo4j 4.0.0 at bolt://localhost:7681 as user neo4j.
Type :help for a list of available commands or :exit to exit the shell.
Note that Cypher queries must end with a semicolon.

neo4j@system> SHOW DATABASES;

+-------------------------------+
| name     | status   | default |
+-------------------------------+
| "neo4j"  | "online" | TRUE    |
| "system" | "online" | FALSE   |
+-------------------------------+

2 rows available after 34 ms, consumed after another 0 ms

neo4j@system> CREATE DATABASE data001;

0 rows available after 378 ms, consumed after another 12 ms
Added 1 nodes, Set 4 properties, Added 1 labels
neo4j@system> SHOW DATABASES;
+--------------------------------+
| name      | status   | default |
+--------------------------------+
| "neo4j"   | "online" | TRUE    |
| "system"  | "online" | FALSE   |
| "data001" | "online" | FALSE   |
+--------------------------------+

3 rows available after 2 ms, consumed after another 1 ms

Source Blocks with title

If a title is provided to the example block, it will show up in an additional blue header above the code:

.This example has a title
[source,adoc]
Play with me!

This example has a title

Play with me!

Copy Button

The Copy To Clipboard button will appear on all code blocks:

[source,adoc]
Copy me!

Unless you add role=nocopy:

[source,adoc,role=nocopy]
Don't copy me!

Reference lines (Callouts)

You can add number bubbles to reference specific lines by appending <n> to a line. It is advised to put them behind a line comment for the language the code is in.

require 'sinatra' (1)

get '/hi' do (2) (3)
  "Hello World!"
end

1	Library import
2	URL mapping
3	Response block

line of code (1)
line of code (2)
line of code (3)
line of code (4)

1	A callout behind a line comment for C-style languages.
2	A callout behind a line comment for Ruby, Python, Perl, etc.
3	A callout behind a line comment for Clojure.
4	A callout behind a line comment for XML or SGML languages like HTML.

Expand code block

Code blocks longer than 15 lines (+5 of tolerance) are collapsed, unless you add role=nocollapse

[source,js]
...

  // Collapse/Expand long blocks
  var codeMaxLines = 15 // lines
  var codeTolerance = 5 // lines
  var codeLineHeight = parseFloat(window.getComputedStyle(
                          document.getElementsByClassName('highlight')[0], null)
                          .getPropertyValue('line-height'))
  var codeMaxHeight = codeLineHeight*codeMaxLines
  var maskImage = 'linear-gradient(to bottom, black 0px, transparent ' +
                   (codeMaxHeight + 100) + 'px)'

  var codeBlockLinesNum = function (code) {
      var paddingTop = parseFloat(window.getComputedStyle(code, null).getPropertyValue('padding-top'))
      var paddingBottom = parseFloat(window.getComputedStyle(code, null).getPropertyValue('padding-bottom'))
      var height = code.clientHeight-paddingTop-paddingBottom;
      var lines = Math.ceil(height / codeLineHeight)
      var hiddenLines = Math.ceil(lines - codeMaxLines)
      return hiddenLines
  }

  var expandCollapseBlock = function (e) {
    e.preventDefault()
    var showMore = e.target
    var pre = showMore.parentNode
    var code = pre.querySelector('code')

    if (pre.style.overflow === 'hidden') {
      window.sessionStorage.setItem('scrollpos', window.scrollY)
      pre.style.maxHeight = pre.scrollHeight + 'px'
      pre.style.overflow = 'visible'
      code.style.webkitMaskImage = ''
      code.style.maskImage = ''
      showMore.innerHTML = '&uarr;' // show less
    } else {
      // Scoll back to where you where before expanding
      var scrollpos = window.sessionStorage.getItem('scrollpos')
      if (scrollpos) {
        window.scrollTo({
          top: scrollpos,
          behavior: 'auto',
        })
      }
      window.sessionStorage.removeItem('scrollpos')

      var hiddenLines = codeBlockLinesNum(code)
      pre.style.maxHeight = codeMaxHeight + 'px'
      pre.style.overflow = 'hidden'
      code.style.webkitMaskImage = maskImage
      code.style.maskImage = maskImage
      showMore.innerHTML = '&darr; View all (' + hiddenLines + ' lines more) &darr;'
    }
  }

  // Collapse long blocks on load
  var collapseCodeBlock = function (pre) {
    var dotContent = pre.parentNode
    var listingBlock = dotContent.parentNode
    var code = pre.querySelector('code')

    if (!listingBlock.classList.contains('nocollapse') &&
        pre.offsetHeight > (codeMaxLines+codeTolerance)*codeLineHeight) {
      pre.style.maxHeight = codeMaxHeight + 'px'
      pre.style.overflow = 'hidden'
      code.style.webkitMaskImage = maskImage
      code.style.maskImage = maskImage

      var hiddenLines = codeBlockLinesNum(code)
      var showMore = createElement('a', 'show-more')
      showMore.innerHTML = '&darr; View all (' + hiddenLines + ' lines more) &darr;'
      showMore.addEventListener('click', expandCollapseBlock)
      pre.appendChild(showMore)
    }
  }

  // Apply collapseCodeBlock
  document.querySelectorAll('.highlight')
    .forEach(collapseCodeBlock)

[source,js,role=nocollapse]
...

// Collapse/Expand long blocks
var codeBlockMaxHeight = 300  // px
var styleMaskImage = 'linear-gradient(to bottom, black 0px, transparent ' + (codeBlockMaxHeight+100) + 'px)'

var expandCollapseBlock = function (e) {
  e.preventDefault();
  var showMore = e.target
  var pre = showMore.parentNode
  var codeBlock = pre.querySelector('code')

  if (pre.st.style.webkitMaskImage = styleMaskImage
    codeBlock.style.maskImage = styleMaskImage
    showMore.innerHTML = '&darr;'  // show more
    //codeBlock.scrollIntoView({behavior: 'smooth'})
  }
}
  if (pre.st.style.webkitMaskImage = styleMaskImage
    codeBlock.style.maskImage = styleMaskImage
    showMore.innerHTML = '&darr;'  // show more
    //codeBlock.scrollIntoView({behavior: 'smooth'})
  }
}

Was this page helpful?