Introduction

In my last blog post, I pro­vid­ed an out­look on run­ning a short­cut that sum­ma­rizes a web­page on an iPhone or iPad. Since it’s not pos­si­ble to run Go on iOS, we need a com­put­er that can be reached via SSH from your device. For con­stant access, it should prefer­ably be up and run­ning 24/7. For me, my Mac­Book Pro would be a good choice, but when I use my iDe­vices, I close the lid, so the iDe­vices have no chance to con­nect.

Choosing the Right Machine

I have two machines run­ning all the time in my net­work: a Syn­ol­o­gy NAS and a Rasp­ber­ry Pi 4 with 4GB of RAM run­ning Ubun­tu 24.04 LTS. Because I am not very expe­ri­enced in cross-com­pil­ing with Go or cre­at­ing Dock­er images, I decid­ed to go with my Rasp­ber­ry Pi.

Since I’m only run­ning Fab­ric with cloud LLMs, in my case with Ope­nAI, there is no need for a lot of com­put­ing pow­er, so the Rasp­ber­ry Pi is more than suf­fi­cient.

But in the end, you can use any com­put­er sys­tem that runs Go.

Preconditions

You need to have a lit­tle exper­tise in Linux/Unix and the Com­mand Line Inter­face (CLI). Besides the instal­la­tion of Go (see the next chap­ter), you should also set up SSH on your Rasp­ber­ry Pi, because the Short­cut will call Fab­ric via “Run Script over SSH”. You should also install git to access the Fab­ric repos­i­to­ry on GitHub, ffmpeg for run­ning the yt com­mand, and wget to fol­low some of my exper­i­ments lat­er on:

sudo apt install git ffmpeg wget

Installation of Go and Fabric

If Go isn’t already installed, you have to install it first. I fol­lowed the “offi­cial” method as described on the GO web­site:

1. Ensure there is no pre­vi­ous ver­sion installed by check­ing if the fold­er /usr/local/go exists. If it does, delete it with sudo rm -rf /usr/local/go.
2. Down­load the lat­est arm64 ver­sion for the Rasp­ber­ry Pi.
3. Install Go. Depend­ing on where you down­loaded the archive, for me it was: tar -C /usr/local -xzf $HOME/Downloads/go1.23.0.linux-amd64.tar.gz.
4. Add the nec­es­sary path infor­ma­tion. For the set­up in my case $HOME/.zshrc. For the short­cut call, I cre­at­ed and used a spe­cial shell lim­it­ed con­fig­u­ra­tion file, sim­i­lar to my macOS set­up, called .fabenv, and added the paths there:
    export PATH=$PATH:/usr/local/go/bin:$HOME/go/bin
5. Install Fab­ric direct­ly from the repos­i­to­ry:
   go install github.com/danielmiessler/fabric@latest.
6. Set up Fab­ric with fabric --setup. Before doing so, read the next para­graph.
7. Install yt if you want to ana­lyze YouTube videos: go install github.com/danielmiessler/yt@latest, but be sure to add your YouTube API key.

Troubleshooting Fabric Setup

When I wrote this, the set­up failed at the end when copy­ing the pat­terns, with the error stream error: stream ID 3; CANCEL; received from peer happened. How­ev­er, the instal­la­tion and set­up com­plet­ed all the nec­es­sary tasks. The only things miss­ing are the fold­ers for the pat­terns, ses­sions, and con­texts. After copied them from my macOS instal­la­tion, Fab­ric ran fine. I hope some­one can fig­ure out why the set­up fails so I can delete this para­graph ;-). If you use anoth­er com­put­er as a serv­er or anoth­er OS on your Rasp­ber­ry Pi, it might work.

Update 2024/09/23: When using an Eth­er­net cable to con­nect the Rasp­ber­ry Pi 4, every­thing works fine. This sug­gests that the issue may be relat­ed to the speed or band­width lim­i­ta­tions of the Wi-Fi chip.

Validating the Installation

All the oth­er infor­ma­tion in my blog post Instal­la­tion and Get­ting Start­ed with Fab­ric is still valid. For exam­ple:

echo "Two parrots on a skyscraper rooftop" | fabric --stream --pattern create_logo

works just like on the Mac.

The “Run Script over SSH” Mystery

As I already men­tioned in my pre­vi­ous blog post Sum­ma­riz­ing Web­sites with Fab­ric and Apple Short­cuts, there is some mys­te­ri­ous behav­ior with Short­cut vari­ables inside and around the shell action, both local and remote.

Passing the URL

For the “Run Script over Shell” action, I tried sev­er­al ways to pass the URL into the action until I found a hint some­where on the web that the eas­i­est way is just to use vari­ables inside the script box:

As you can see, this is an exam­ple in the macOS Short­cuts app, and it works fine. You can use this solu­tion instead of the workaround in my pre­vi­ous blog post.

I ini­tial­ly thought that if it works on macOS, it should also work in the iOS/iPadOS Short­cuts app. So, I copied the short­cut. How­ev­er, it didn’t work at all, which was frus­trat­ing.

After hours of exper­i­ment­ing, I found that this con­struct works, though I’m not sure why the easy one line com­mand does­n’t work:

Using curl Instead of wget

There is anoth­er com­mand to down­load the con­tent of URLs in the Lin­ux and macOS tool­box: curl. Out of curios­i­ty, I tried this com­mand. To my sur­prise, there is no need for the com­plex con­struc­tion that I had to use with wget.

Although I’ve been using wget for ages, I think I have to switch over to curl. Because of all the trou­ble, I didn’t go the extra mile to extract the text from the HTML with pandoc. So this will be the pre­ferred solu­tion.

An Unexpected Working Solution

For the sake of com­plete­ness, here is anoth­er approach. Dur­ing my exper­i­ments, I made a small mis­take and end­ed up with this com­mand, which sur­pris­ing­ly works as well:

I assume it might be because the vari­able URL is inter­nal­ly treat­ed as some kind of struc­ture that always has all infor­ma­tion avail­able, and some mag­ic fetch­es the right val­ue for a giv­en con­text. For exam­ple, if you just echo the vari­able URL, the out­put is sim­ply the URL.

The iOS/iPasOS Shortcut

The work­flow is the same as in the macOS work­flow:

1. Use Receive What’s Onscreen to work in all web browsers.
2. Assign the URL of the active web­site to the vari­able URL.
3. Assign the title to the vari­able name.
4. Delete : and / in the vari­able name, because these char­ac­ters cause issues in file names (this could be extend­ed to oth­er char­ac­ters like ?).
5. Use Run Script over SSH with the IP address or name of your serv­er, the user and pass­word, and the script dis­cussed above.
6. Put the result into the vari­able summary.
7. Cre­ate the note for Obsid­i­an in a text box, includ­ing the prop­er­ties sec­tion and, if need­ed, a foot­er area.
8. Save it with the Cre­ate Note action of the Action­ForOb­sid­i­an (AFO) Short­cuts Exten­sion App.
9. Use “AFO” to open the new­ly cre­at­ed note.

I use “AFO” to save the note in my Obsid­i­an vault because it’s very easy to han­dle. It is worth invest­ing in this exten­sion, as its col­lec­tion of Obsid­i­an-relat­ed actions helps bridge the gap between the Short­cuts app and Obsid­i­an. Nev­er­the­less, you can also use the save-file action or move the result to the Notes app.

Conclusion

This is just an exam­ple of how to inte­grate a remote­ly run­ning Fab­ric instal­la­tion into iOS/iPadOS Short­cuts. This approach opens up a uni­verse of pos­si­bil­i­ties. Any­thing that runs on a remote machine and con­sumes text input or cre­ates text out­put on the ter­mi­nal (stdin/stdout) can be used to cre­ate com­plex work­flows with Fab­ric, there­by eas­i­ly becom­ing AI-sup­port­ed.

I hope this blog post is over­all help­ful, despite the lit­tle hur­dles. It would be great if some­one could explain the mys­te­ri­ous behav­ior of the URL vari­able. I would also love to learn how to avoid the Fab­ric set­up error. Crit­ics, kudos, more ideas, and what­ev­er else—please leave them in the com­ments.