Author: dustin

Measure Internet Speed from CLI

Leave a comment

Use speedtest-cli:

$ curl -s https://raw.githubusercontent.com/sivel/speedtest-cli/master/speedtest.py | python -
Retrieving speedtest.net configuration...
Testing from Comcast Cable (73.1.128.16)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by Broadwave (Fort Lauderdale, FL) [43.78 km]: 22.155 ms
Testing download speed................................................................................
Download: 232.72 Mbit/s
Testing upload speed......................................................................................................
Upload: 10.07 Mbit/s

Jenkins: Accessing REST API for a Specific Plugin

Some plugins may extent the Jenkins API with additional functionality. To [blindly] determine if this is the case for a particular plugin of interest, first enumerate the list of installed plugins:

https://<jenkins server>/pluginManager/api/json?depth=2

Then, find the plugin in the list and get the value from its “shortName” field:

Selection_20193009-23:57:31_01.png

That value is the name used in the API URL. In this case, that URL would be https://<jenkins server>/gerrit-trigger​. This might be enough to get you what you need, though, depending on the plugin, you might have to reverse-engineer the plugins’ sourcecode in order to find which further nouns/entity subpaths are available from here. You might do a Google search and then grep for the paths that you find from that in order to discover siblings.

This is not meant to be a complicated post, though the information is made complicated by the effort required to find the information.

go-exfat

I’m a Linux guy, but the lure of a new filesystem spec can not be denied.

This is a read-only exFAT impementation in pure Go. This provides a direct API, but several command-line tools were also made available with which to inspect the filesystem’s structure. There’s 90% test-coverage and an A+ on the score-card.

https://github.com/dsoprea/go-exfat

Go: An In-Memory ReadWriteSeeker

The SeekableBuffer type is similar to a bytes.Buffer in that you can perform both reads and writes against it, but has the following two main differences:

  1. You can seek on it.
  2. After writing to it, the current position will be on the byte following whatever you wrote. This is the typical behavior for a file resource on almost any platform but not for a bytes.Buffer.

Eccentric usage of seek, read, and write behavior, such as the following, will work as expected:

  • seeking but not writing
  • seeking past the end of the file and writing
  • seeking past the end of the file and reading
  • writing N+M bytes when positioned only N bytes from the end of the file

Usage (from the unit-tests):

sb := NewSeekableBuffer()

// Write first string.

data := []byte("word1-word2")

_, err := sb.Write(data)
log.PanicIf(err)

// Seek and replace partway through, and replace more data than we
// currently have.

_, err = sb.Seek(6, os.SEEK_SET)
log.PanicIf(err)

data2 := []byte("word3-word4")

_, err = sb.Write(data2)
log.PanicIf(err)

// Read contents.

_, err = sb.Seek(0, os.SEEK_SET)
log.PanicIf(err)

buffer := make([]byte, 20)

_, err = sb.Read(buffer)
log.PanicIf(err)

// `buffer` currently has "word1-word3-word4".