Episode 267

JSJ 266 NPM 5.0 with Rebecca Turner


June 20th, 2017

41 mins 40 secs

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About this Episode

On today’s episode of JavaScript Jabber, Charles Max Wood and panelist Joe Eames chat with Rebecca Turner, tech lead for NPM, a popular Javascript package manager with the worlds largest software registry. Learn about the newly released NPM 5 including a few of the updated features. Stay tuned!

[1:58] Was the release of node JS 8 tied to NPM5?
  • Features in NPM5 have been in planning for 2 years now.
  • Planned on getting it out earlier this year.
  • Node 8 was coming out and got pushed out a month.
  • Putting NPM5 into Node 8 became doable.
  • Pushed really hard to get NPM5 into Node 8 so that users would get NPM5 and updates to NPM5.
[2:58] Why would it matter? NPM doesn’t care right?
  • Right you can use NPM5 with any version of node.
  • Most people don’t update NPM, but upgrade Node.
  • So releasing them together allowed for when people updated Node they would get NPM 5.
[3:29] How does the upgrade process work if you’re using NVM or some node version manager?
  • Depends. Different approaches for each
  • NVM gets a fresh copy of Node with new globals. NVM5 and Node 8 are bundled.
  • For some, If you manually upgrade NVM you’ll always have to manually. It will keep the one you manually upgraded to.
[4:16] Why NPM 5?
  • It’s night and day faster.
  • 3 to 5 times speed up is not uncommon.
  • Most package managers are slow.
  • NPM 5 is still growing. Will get even faster.
[5:18] How did you make it faster?
  • The NPM’s cache is old. It’s very slow. Appalling slow.
  • Rewrote cache
  • Saw huge performance gains
[5:49] What is the function of the cache?
  • Cache makes it so you don’t have to reinstall modules from the internet.
  • It has registry information too.
  • It will now obey http headers for timing out cache.
[6:50] Other things that made it faster?
  • Had a log file for a long time. It was called shrinkwrap.
  • NPM 5 makes it default.
  • Renamed it to packagelog.json
  • Exactly like shrinkwrap package file seen before
  • In combo with cache, it makes it really fast.
  • Stores information about what the tree should look like and it’s general structure.
  • It doesn’t have to go back and learn versions of packages.
[7:50] Can you turn the default Packagelog.json off?
  • Yes. Just:
  • Set packagelog=false in the npmrc
[8:01] Why make it default? Why wasn’t it default before?
  • It Didn’t have it before. Shrinkwrap was added as a separate project enfolded in NPM and wasn’t core to the design of NPM.
  • Most people would now benefit from it. Not many scenarios where you wouldn’t want one.
  • Teams not using the same tools causes headaches and issues.
[9:38] Where does not having a lock show up as a problem?
  • It records the versions of the packages installed and where NPM put them so that when you clone a project down you will have exactly the same versions across machines.
  • Collaborators have the exact same version.
  • Protects from issues after people introduce changes and patch releases.
  • NPM being faster is just a bonus.
  • Store the sha512 of the package that was installed in the glock file so that we can verify it when you install. It’s Bit for bit what you had previously.
[11:12] Could you solve that by setting the package version as the same version as the .Json file?
  • No. That will lock down the versions of the modules that you install personally, not the dependancies, or transitive dependancies.
  • Package log allows you to look into the head of the installer. This is what the install looks like.
[12:16] Defaulting the log file speed things up? How?
  • It doesn’t have to figure out dependences or the tree which makes it faster.
  • Shrinkwrap command is still there, it renames it to shrinkwrap but shrinkwrap cannot be published.
  • For application level things or big libraries, using shrinkwrap to lock down versions is popular.
[13:42] You’ve Adopted specifications in a ROC process. When did you guys do that?
  • Did it in January
  • Have been using them internally for years. Inviting people into the process.
  • Specifications
  • Written in the form of “Here is the problem and here are the solutions.”
  • Spec folder in NPM docs, things being added to that as they specify how things work.
  • Spec tests have been great.
[14:59] The update adds new tools. Will there be new things in registry as well?
  • Yes.
  • Information about a package from registry, it returns document that has info about every version and package json data and full readme for every version.
  • It gets very large.
  • New API to request smaller version of that document.
  • Reduces bandwidth, lower download size, makes it substantially faster.
  • Used to be hashed with sha1, With this update it will be hashed with sha512 as well as sha1 for older clients.
[16:20] Will you be stopping support for older versions?
  • LTS version of NPM was a thing for a while. They stopped doing that.
  • Two models, people either use whatever version came with Node or they update to the latest.
  • The NPM team is really small. Hard to maintain old NPM branches.
  • Supports current versions and that’s pretty much it.
  • If there are big problems they will fix old versions. Patches , etc.
[17:36] Will there ever be problems with that?
  • Older versions should continue to work. Shouldn’t break any of that.
  • Can’t upgrade from 0.8.
  • It does break with different Node version
  • Does not support Node versions 0.10 or 0.12.
[18:47] How do you upgrade to NPM?
  • sudo npm install -gmpm
  • Yes, you may not need sudo. depend on what you’re on.
[19:07] How long has it been since version 4?
  • Last October is when it came out.
[19:24] Do you already have plans for version 6?
  • Yes!
  • More releases than before coming up.
  • Finally deprecating old features that are only used in a few packages out of the whole registry.
  • Running tests on getting rid of things.
[20:50] Self healing cache. What is it and why do we want it?
  • Users are sometimes showing up where installs are broken and tarbols are corrupted.
  • This happens sometimes with complicated containerization setups makes it more likely. It’s unclear where the problem actually is.
  • CaCache - content addressable cache. Take the hash of your package and use it to look up address to look it up in the cache.
  • Compares the Tarbol using an address to look it up in the cache.
  • Compares to see if it’s old. Trashes old and downloads updated one.
  • Came out with the cache. Free side effect of the new cache.
[23:14] New information output as part of the update?
  • NPM has always gave back you the tree from what you just installed.
  • Now, trees can be larger and displaying that much information is not useful.
  • User patch - gives you specifically what you asked for.
  • Information it shows will be something like: “I installed 50 items, updated 7, deleted 2.”
[24:23] Did you personally put that together?
  • Yes, threw it together and then got feedback from users and went with it.
  • Often unplanned features will get made and will be thrown out to get feedback.
  • Another new things ls output now shows you modules that were deduped. Shows logical tree and it’s relationships and what was deduped.
[25:27] You came up to node 4 syntax. Why not go to node 8?
  • To allow people with just node 4 be able to use NPM.
  • Many projects still run Node 4. Once a project has been deployed, people generally don’t touch it.
[26:20] Other new features? What about the File Specifier?
  • File specifier is new. File paths can be in package json, usually put inside pointing to something inside your package.
  • It will copy from there to your node modules.
  • Just a node module symlink.
  • Much faster. Verifiable that what’s in your node modules matches the source. If it’s pointing at the right place it’s correct. If not, then it’s not.
  • Earlier, sometimes it was hard to tell.
[27:38] Anything else as part of the NPM 5 release? Who do you think will be most affected by it?
  • For the most part, people notice three things:
  • 1st. no giant tree at the end
  • 2nd. Much faster
  • 3rd. Package lock.
[28:14] If it’s locked, how do you update it?
  • Run npm installer and then npm update
  • Used to be scary, but works well now.
  • Updates to latest semver, matches semver to package json to all node modules.
  • Updates package lock at the same time
  • Summary in Git shows what’s changed.
[28:59] Did Yarn come into play with your decisions with this release?
  • The plans have been in play for a long time for this update.
  • Yarn’s inclusion of similar features and the feedback was an indicator that some of the features were valuable.
[29:53] Other plans to incorporate features similar to yarn?
  • Features are already pretty close.
  • There are other alternative package managers out there.
  • PMPM interesting because when it installs it doesn’t copy all the files. It creates hard links.
[30:28] Does PMPM and Yarn use NPM registry?
  • Yes! Other than CNPM. The NPM client used in China.
  • CNPM Registry mirror behind firewall. Have their own client to their registry. Their registry is a copy of ours.
[31:15] What about RNPM?
  • I wouldn’t be surprised.
[31:45] “Won’t you come and say something controversial about your competitor?”
  • We all want it to be collaborative.
  • When we were writing our new cache, we also helped Yarn with their cache and sped things up tremendously.



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Links to keep up with NPM and Rebecca

Twitter @rebeccaorg
NPMjS on Twitter