Merge 5365e75267 into 01c9c0d19b

README.md

@@ -10,7 +10,7 @@ pairing with smart people at Hashrocket.
 
 For a steady stream of TILs, [sign up for my newsletter](https://crafty-builder-6996.ck.page/e169c61186).
 
-_1408 TILs and counting..._
+_1424 TILs and counting..._
 
 ---
 
@@ -41,6 +41,7 @@ _1408 TILs and counting..._
 * [jq](#jq)
 * [Kitty](#kitty)
 * [Linux](#linux)
+* [LLM](#llm)
 * [Mac](#mac)
 * [MongoDB](#mongodb)
 * [MySQL](#mysql)
@@ -98,6 +99,7 @@ _1408 TILs and counting..._
 ### Brew
 
 - [Configure Brew Environment Variables](brew/configure-brew-environment-variables.md)
+- [List All Services Managed By Brew](brew/list-all-services-managed-by-brew.md)
 
 ### Chrome
 
@@ -259,6 +261,7 @@ _1408 TILs and counting..._
 
 - [Accessing a Lost Commit](git/accessing-a-lost-commit.md)
 - [Add A Range Of Filename To gitignore](git/add-a-range-of-filenames-to-gitignore.md)
+- [Add Only Tracked Files From A Directory](git/add-only-tracked-files-from-a-directory.md)
 - [Amend Author Of Previous Commit](git/amend-author-of-previous-commit.md)
 - [Auto-Squash Those Fixup Commits](git/auto-squash-those-fixup-commits.md)
 - [Caching Credentials](git/caching-credentials.md)
@@ -408,6 +411,7 @@ _1408 TILs and counting..._
 
 ### Inngest
 
+- [Ensure Lookup Can Be Retried](inngest/ensure-lookup-can-be-retried.md)
 - [Exit Function Early Without Retries](inngest/exit-function-early-without-retries.md)
 
 ### Internet
@@ -437,6 +441,7 @@ _1408 TILs and counting..._
 - [Computed Property Names In ES6](javascript/computed-property-names-in-es6.md)
 - [Conditionally Include Pairs In An Object](javascript/conditionally-include-pairs-in-an-object.md)
 - [Configure Jest To Run A Test Setup File](javascript/configure-jest-to-run-a-test-setup-file.md)
+- [Convert Seconds To Date Object](javascript/convert-seconds-to-date-object.md)
 - [Create A Cancelable Promise With PCancelable](javascript/create-a-cancelable-promise-with-pcancelable.md)
 - [Create An Array Containing 1 To N](javascript/create-an-array-containing-1-to-n.md)
 - [Create An Object With No Properties](javascript/create-an-object-with-no-properties.md)
@@ -553,6 +558,11 @@ _1408 TILs and counting..._
 - [Show Used And Available System Memory](linux/show-used-and-available-system-memory.md)
 - [Upgrading Ubuntu](linux/upgrading-ubuntu.md)
 
+### LLM
+
+- [Send cURL To Claude Text Completion API](llm/send-curl-to-claude-text-completion-api.md)
+- [Use The llm CLI With Claude Models](llm/use-the-llm-cli-with-claude-models.md)
+
 ### Mac
 
 - [Access All Screen And Video Capture Options](mac/access-all-screen-and-video-capture-options.md)
@@ -664,6 +674,7 @@ _1408 TILs and counting..._
 - [Capitalize All The Words](postgres/capitalize-all-the-words.md)
 - [Change The Current Directory For psql](postgres/change-the-current-directory-for-psql.md)
 - [Change The Owner Of A Sequence](postgres/change-the-owner-of-a-sequence.md)
+- [Check If Clusters Are Upgrade Compatible](postgres/check-if-clusters-are-upgrade-compatible.md)
 - [Check If The Local Server Is Running](postgres/check-if-the-local-server-is-running.md)
 - [Check If User Role Exists For Database](postgres/check-if-user-role-exists-for-database.md)
 - [Check Table For Any Oprhaned Records](postgres/check-table-for-any-orphaned-records.md)
@@ -680,6 +691,7 @@ _1408 TILs and counting..._
 - [Count How Many Records There Are Of Each Type](postgres/count-how-many-records-there-are-of-each-type.md)
 - [Count Records By Type](postgres/count-records-by-type.md)
 - [Count The Number Of Trues In An Aggregate Query](postgres/count-the-number-of-trues-in-an-aggregate-query.md)
+- [Create A Cluster In A Specific Data Directory](postgres/create-a-cluster-in-a-specific-data-directory.md)
 - [Create A Composite Primary Key](postgres/create-a-composite-primary-key.md)
 - [Create A Table From The Structure Of Another](postgres/create-a-table-from-the-structure-of-another.md)
 - [Create An Index Across Two Columns](postgres/create-an-index-across-two-columns.md)
@@ -727,6 +739,7 @@ _1408 TILs and counting..._
 - [Group By The Result Of A Function Call](postgres/group-by-the-result-of-a-function-call.md)
 - [Idempotent Inserts](postgres/idempotent-inserts.md)
 - [Include All Queries In The Log File](postgres/include-all-queries-in-the-log-file.md)
+- [Include Columns In A Covering Index](postgres/include-columns-in-a-covering-index.md)
 - [Include Multiple Tables In A pg_dump](postgres/include-multiple-tables-in-a-pg-dump.md)
 - [Insert A Bunch Of Records With Generate Series](postgres/insert-a-bunch-of-records-with-generate-series.md)
 - [Insert Just The Defaults](postgres/insert-just-the-defaults.md)
@@ -819,6 +832,7 @@ _1408 TILs and counting..._
 - [Access Instance Variables](python/access-instance-variables.md)
 - [Create A Dummy DataFrame In Pandas](python/create-a-dummy-dataframe-in-pandas.md)
 - [Test A Function With Pytest](python/test-a-function-with-pytest.md)
+- [Use pipx To Install End User Apps](python/use-pipx-to-install-end-user-apps.md)
 
 ### Rails
 
@@ -879,6 +893,7 @@ _1408 TILs and counting..._
 - [Get ActiveRecord Attribute Directly From Database](rails/get-active-record-attribute-directly-from-database.md)
 - [Get An Array Of Values From The Database](rails/get-an-array-of-values-from-the-database.md)
 - [Get An Empty ActiveRecord Relation](rails/get-an-empty-activerecord-relation.md)
+- [Get Formatted UTC Offset Value](rails/get-formatted-utc-offset-value.md)
 - [Get Help With A Rails App Update](rails/get-help-with-a-rails-app-update.md)
 - [Get The Column Names For A Model](rails/get-the-column-names-for-a-model.md)
 - [Get The Current Time](rails/get-the-current-time.md)
@@ -894,6 +909,7 @@ _1408 TILs and counting..._
 - [Load A File When Starting Rails Console](rails/load-a-file-when-starting-rails-console.md)
 - [Load Records In Batches With find_each](rails/load-records-in-batches-with-find-each.md)
 - [Log SQL Queries Executed By ActiveRecord](rails/log-sql-queries-executed-by-activerecord.md)
+- [Look Up Time Zone Info For Identifier](rails/look-up-time-zone-info-for-identifier.md)
 - [Mark A Migration As Irreversible](rails/mark-a-migration-as-irreversible.md)
 - [Make A String Attribute Easy To Inquire About](rails/make-a-string-attribute-easy-to-inquire-about.md)
 - [Make ActionMailer Synchronous In Test](rails/make-action-mailer-synchronous-in-test.md)
@@ -1114,6 +1130,7 @@ _1408 TILs and counting..._
 - [Defaulting To Frozen String Literals](ruby/defaulting-to-frozen-string-literals.md)
 - [Define A Custom RSpec Matcher](ruby/define-a-custom-rspec-matcher.md)
 - [Define A Method On A Struct](ruby/define-a-method-on-a-struct.md)
+- [Define Multiline Strings With Heredocs](ruby/define-multiline-strings-with-heredocs.md)
 - [Destructure The First Item From An Array](ruby/destructure-the-first-item-from-an-array.md)
 - [Destructuring Arrays In Blocks](ruby/destructuring-arrays-in-blocks.md)
 - [Disassemble Some Codes](ruby/disassemble-some-codes.md)
@@ -1137,6 +1154,7 @@ _1408 TILs and counting..._
 - [Generate Ruby Version And Gemset Files With RVM](ruby/generate-ruby-version-and-gemset-files-with-rvm.md)
 - [Get Info About Your RubyGems Environment](ruby/get-info-about-your-ruby-gems-environment.md)
 - [Get The Output Of Running A System Program](ruby/get-the-output-of-running-a-system-program.md)
+- [Get UTC Offset For Different Time Zones](ruby/get-utc-offset-for-different-time-zones.md)
 - [Identify Outdated Gems](ruby/identify-outdated-gems.md)
 - [If You Detect None](ruby/if-you-detect-none.md)
 - [Iterate With An Offset Index](ruby/iterate-with-an-offset-index.md)
@@ -1612,6 +1630,7 @@ _1408 TILs and counting..._
 - [Add The VSCode CLI To Your Path](vscode/add-the-vscode-cli-to-your-path.md)
 - [Advance Through Search Results](vscode/advance-through-search-results.md)
 - [Enable Breadcrumbs For Version 1.26 Release](vscode/enable-breadcrumbs-for-version-126-release.md)
+- [Find The Location Of User Settings JSON File](vscode/find-the-location-of-user-settings-json-file.md)
 - [Open An Integrated Terminal Window](vscode/open-an-integrated-terminal-window.md)
 - [Pop Open The Quick Fix Window](vscode/pop-open-the-quick-fix-window.md)
 - [Step Through Project-Wide Search Results](vscode/step-through-project-wide-search-results.md)
@@ -1629,6 +1648,7 @@ _1408 TILs and counting..._
 ### Workflow
 
 - [Add Subtitles To Existing Mux Video Asset](workflow/add-subtitles-to-existing-mux-video-asset.md)
+- [Access 1Password Credential From CLI](workflow/access-1password-credential-from-cli.md)
 - [Change Window Name In iTerm](workflow/change-window-name-in-iterm.md)
 - [Convert An ePub Document To PDF On Mac](workflow/convert-an-epub-document-to-pdf-on-mac.md)
 - [Create A Local Sanity Dataset Backup](workflow/create-a-local-sanity-dataset-backup.md)

brew/list-all-services-managed-by-brew.md

@@ -0,0 +1,28 @@
+# List All Services Managed By Brew
+
+Daemonized services, such as PostgreSQL, can be installed and managed with
+Homebrew. Under the hood `brew` uses `launchctl` on Mac to manage these
+services — i.e. starting, restarting, and stopping them.
+
+Assuming you've already installed some services, you can run `brew services
+list` to see what services there are and what their current status is.
+
+```bash
+$ brew services list
+Name          Status  User       File
+mailhog       none
+mysql         none
+postgresql@11 started jbranchaud ~/Library/LaunchAgents/homebrew.mxcl.postgresql@11.plist
+postgresql@13 none
+postgresql@16 none
+unbound       none
+```
+
+This is the default behavior if you just run `brew services` without a subcommand.
+
+This is helpful if you are, for instance, trying to see which PostgreSQL server
+version you are currently running and which other ones are available to run. I
+might then issue a `stop` to `postgresql@11` so that I can then `start` the
+`postgresql@16` service.
+
+See `brew services --help` for more details.

git/add-only-tracked-files-from-a-directory.md

@@ -0,0 +1,26 @@
+# Add Only Tracked Files From A Directory
+
+The two extremes of staging files in a git repo are to either selectively pick
+each individual chunk of changes with `git add --patch` (my preference!) or to
+run `git add -A` to add everything.
+
+Now let's say I have large directory full of files that get generated during
+test runs. Most of these files are tracked (already checked in to the
+repository). There are also many new files generated as part of the most recent
+test run.
+
+I want to staging the changes to files that are already tracked, but hold off
+on doing anything with the new files.
+
+Running `git add spec/cassettes` won't do the track because that will pull in
+everything. Running `git add --patch spec/cassettes` will take long and be
+tedious. Instead what I want is the `-u` flag. It's short for _update_ which
+means it will only stage already tracked files.
+
+```bash
+$ git add -u spec/cassettes
+```
+
+That will stage every change to any already known files in `spec/cassettes`.
+
+See `man git-add` for more details.

git/viewing-a-file-on-another-branch.md

@@ -2,16 +2,16 @@
 
 Sometimes you want to view a file on another branch (without switching
 branches). That is, you want to view the version of that file as it exists
-on that branch. `git show` can help. If your branch is named `my_feature` and
+on that branch. `git show` can help. If the other branch is named `some_branch` and
 the file you want to see is `app/models/users.rb`, then your command should
 look like this:
 
 ```
-$ git show my_feature:app/models/users.rb
+$ git show some_branch:app/models/users.rb
 ```
 
 You can even tab-complete the filename as you type it out.
 
 See `man git-show` for more details.
 
-[source](http://stackoverflow.com/questions/7856416/view-a-file-in-a-different-git-branch-without-changing-branches)
+[source](https://stackoverflow.com/questions/7856416/view-a-file-in-a-different-git-branch-without-changing-branches)

inngest/ensure-lookup-can-be-retried.md

@@ -0,0 +1,57 @@
+# Ensure Lookup Can Be Retried
+
+A common thing to do in a workflow step is to look up a record. This might be a
+record that was created or updated around the time that the workflow was
+triggered.
+
+You need to be sure the record was found before proceeding. That might end up
+looking like this:
+
+```typescript
+export default inngest.createFunction(
+  { id: "record-user-purchase" },
+  { event: "app/record.purchase" },
+  async ({ event, step }) => {
+    const checkoutSession =
+      await step.run("find checkout session", async () => {
+        const cs = provider.lookupSession(event.checkoutSessionId)
+
+        return cs;
+      });
+
+    if(!checkoutSession) {
+      throw new Error('Checkout session not found')
+    }
+  }
+);
+```
+
+This approach has a subtle problem which is that the error for a missing
+checkout session is raised _outside_ the step that sets `checkoutSession`. As
+inngest does a series of retries, the memorized `checkoutSession` step won't be
+rerun and the error will continue to be thrown.
+
+It is better to raise the error _within_ the lookup step:
+
+```typescript
+export default inngest.createFunction(
+  { id: "record-user-purchase" },
+  { event: "app/record.purchase" },
+  async ({ event, step }) => {
+    const checkoutSession =
+      await step.run("find checkout session", async () => {
+        const cs = provider.lookupSession(event.checkoutSessionId)
+
+        if(!cs) {
+          throw new Error('Checkout session not found')
+        }
+
+        return cs;
+      });
+  }
+);
+```
+
+If the checkout session is missing on the first couple tries, the step will
+have a chance to retry the lookup and maybe eventually find what it is looking
+for.

javascript/convert-seconds-to-date-object.md

@@ -0,0 +1,32 @@
+# Convert Seconds To Date Object
+
+Let's say you have an integer that represents the number of seconds since the
+unix epoch. This is a reasonably common way for systems to represent a date.
+
+For example, `1713350171` is an _Expiration Date_ I just got from an API.
+
+But how do we know what date that actually represents and how can we get a
+JavaScript `Date` object from that value?
+
+The `new Date()` constructor can produce a date object given an integer. That
+integer is not supposed to be seconds since the unix epoch though. See what we
+get here:
+
+```javascript
+> new Date(1713350171)
+1970-01-20T19:55:50.171Z
+```
+
+Something is off. The integer that you pass to `new Date()` needs to be the
+_number of milliseconds_ since the unix epoch. We can get there by multiplying
+our _seconds_ value by `1000`.
+
+```javascript
+> new Date(1713350171 * 1000)
+2024-04-17T10:36:11.000Z
+```
+
+Not only can we, as humans, read that date, but we have a `Date` object that we
+can use within our program.
+
+Note: if you execute `Date.now()`, the value you get is in milliseconds.

llm/send-curl-to-claude-text-completion-api.md

@@ -0,0 +1,40 @@
+# Send cURL To Claude Text Completion API
+
+Here is how we can make a `cURL` (`POST`) request to the Claude text completion
+API. It requires already having a Claude API account with (paid) credits. At
+this time, you can get $5 in free credits to try it out.
+
+Assuming all that, we can grab an API key, store it somewhere safe and
+accessible like 1Password, and then start formatting a request.
+
+We need to specify a couple headers as well as `POST` body parameters.
+
+```bash
+curl -X POST \
+  -H "Content-Type: application/json" \
+  -H "x-api-key: $(op item get "Anthropic Claude API Key" --field credential)" \
+  -H "anthropic-version: 2023-06-01" \
+  -d \
+'{
+  "model": "claude-2.1",
+  "max_tokens_to_sample": 1024,
+  "prompt": "Human: Show me an example of a simple Ruby program.\n\nAssistant:"
+}' \
+  https://api.anthropic.com/v1/complete
+```
+
+The required headers are:
+- `"Content-Type: application/json"`
+- `x-api-key` with our API key
+- `"anthropic-version: 2023-06-01"` (the latest Anthropic API version)
+
+Then, in the body, we specify:
+- the `model` (e.g. `claude-2.1`)
+- the max number of tokens you want the model to use
+- a prompt that starts with `Human:` and then prompts the `Assistant:`
+
+Note: this is a legacy API and the [Messages
+API](https://docs.anthropic.com/claude/reference/messages_post) should be
+preferred.
+
+[source](https://docs.anthropic.com/claude/reference/complete_post)

llm/use-the-llm-cli-with-claude-models.md

@@ -0,0 +1,26 @@
+# Use The llm CLI With Claude Models
+
+[Simon Willison's `llm`](https://llm.datasette.io/en/stable/index.html) can be
+used with a bunch of different models (local and API). The whole thing is
+plugin driven. To use a specific model, you'll need to install the plugin for
+it. For instance, to use the [Claude 3 family of
+models](https://www.anthropic.com/news/claude-3-family) you need to install
+`llm-claude-3`.
+
+```bash
+$ llm install llm-claude-3
+```
+
+Then when prompting `llm`, specify which of the Claude models you want to use —
+`claude-3-haiku`, `claude-3-sonnet`, or `claude-3-opus` — with the `-m` flag:
+
+```bash
+$ llm \
+  -m claude-3-haiku \
+   --key $CLAUDE_API_KEY \
+  'Show me the SQL query to create a cocktails table.'
+```
+
+Note: instead of adding my Claude API key to the key store, I've opted to
+include it with the `--key` flag via an environment variable that I've set
+ahead of time.

postgres/check-if-clusters-are-upgrade-compatible.md

@@ -0,0 +1,42 @@
+# Check If Clusters Are Upgrade Compatible
+
+One of the ways to upgrade a PostgreSQL database from one server version to
+another is to use the built-in `pg_upgrade` command. This can be faster and
+require fewer manual steps than something like a `pg_dump` and `pg_restore`.
+
+However, before you run the `pg_upgrade` command for real, you should check
+that the target database is compatible with the current database. To do this,
+write your `pg_update` command with all the flags you need and then tack on
+`--check` at the end. This does a dry-run reporting the results of a series of
+consistency checks.
+
+Here is what a successful _check_ looks like:
+
+```bash
+$ /usr/local/opt/postgresql@13/bin/pg_upgrade \
+  --old-bindir $HOME/.asdf/installs/postgres/12.3/bin \
+  --new-bindir /usr/local/opt/postgresql@13/bin \
+  --old-datadir $HOME/.asdf/installs/postgres/12.3/data \
+  --new-datadir ./postgres/data \
+  --check
+
+Performing Consistency Checks
+-----------------------------
+Checking cluster versions                                   ok
+Checking database user is the install user                  ok
+Checking database connection settings                       ok
+Checking for prepared transactions                          ok
+Checking for system-defined composite types in user tables  ok
+Checking for reg* data types in user tables                 ok
+Checking for contrib/isn with bigint-passing mismatch       ok
+Checking for presence of required libraries                 ok
+Checking database user is the install user                  ok
+Checking for prepared transactions                          ok
+Checking for new cluster tablespace directories             ok
+
+*Clusters are compatible*
+```
+
+If there is an issue, such as mismatched collation settings, the output will
+report the issue. You'll have to decide how to resolve those on a case-by-case
+basis.

postgres/create-a-cluster-in-a-specific-data-directory.md

@@ -0,0 +1,46 @@
+# Create A Cluster In A Specific Data Directory
+
+Let's say I want to create a PostgreSQL cluster near my app. So, I create a
+`postgres/data` directory next to my app. Then I run the `initdb` command
+pointing at that directory and specifying the UTF-8 locale.
+
+Here is what that looks like:
+
+```bash
+$ /usr/local/opt/postgresql@13/bin/initdb -D postgres/data --locale=en_US.UTF-8
+
+The files belonging to this database system will be owned by user "jbranchaud".
+This user must also own the server process.
+
+The database cluster will be initialized with locale "en_US.UTF-8".
+The default database encoding has accordingly been set to "UTF8".
+The default text search configuration will be set to "english".
+
+Data page checksums are disabled.
+
+fixing permissions on existing directory postgres/data ... ok
+creating subdirectories ... ok
+selecting dynamic shared memory implementation ... posix
+selecting default max_connections ... 100
+selecting default shared_buffers ... 128MB
+selecting default time zone ... America/Chicago
+creating configuration files ... ok
+running bootstrap script ... ok
+performing post-bootstrap initialization ... ok
+syncing data to disk ... ok
+
+initdb: warning: enabling "trust" authentication for local connections
+You can change this by editing pg_hba.conf or using the option -A, or
+--auth-local and --auth-host, the next time you run initdb.
+
+Success. You can now start the database server using:
+
+    '/usr/local/opt/postgresql@13/bin/pg_ctl' -D postgres/data -l logfile start
+```
+
+As stated at the end of the command's output, I can run the `postgres` server
+with that data directory with:
+
+```bash
+$ '/usr/local/opt/postgresql@13/bin/pg_ctl' -D postgres/data -l logfile start
+```

postgres/include-columns-in-a-covering-index.md

@@ -0,0 +1,33 @@
+# Include Columns In A Covering Index
+
+A _covering index_ is a special type of B-Tree index that, in addition to
+indexing on a certain field, also _includes_ one or more columns as extra data
+in the leaves of the tree. When created correctly, this can speed up the
+queries it targets by achieving an _index-only scan_.
+
+Let's say we have a frequently run query on a large `events` table that looks
+like this:
+
+```sql
+select user_id, identifier, type
+  from events
+  where user_id = $1;
+```
+
+Here is what it looks like to create an index for this query with the `include`
+keyword:
+
+```sql
+create index user_id_on_events_idx
+  on (user_id)
+  include (identifier, type);
+```
+
+An index on its own can already cause a significant speed up to the queries it
+targets, but may still need to retrieve some `select` attributes from the
+table. For hot-path queries with a set of specific columns always included in
+the select, there can be significant additional speed ups by having the index
+_cover_ those columns.
+
+For more details, check out [A Close Look At The Index Include
+Clause](https://use-the-index-luke.com/blog/2019-04/include-columns-in-btree-indexes).

python/use-pipx-to-install-end-user-apps.md

@@ -0,0 +1,31 @@
+# Use pipx To Install End User Apps
+
+The [`pipx`](https://pipx.pypa.io/stable/) tool is an installer for the python
+ecosystem. It differs from `pip` in that it is for installing end-user
+applications and it does so in isolated environments.
+
+You can install `pipx` with an OS-specific installer like Homebrew:
+
+```bash
+$ brew install pipx
+```
+
+Ensure `pipx`-installed apps are on your path:
+
+```bash
+$ pipx ensurepath
+```
+
+Then use `pipx` to install programs like
+[`cowsay`](https://pypi.org/project/cowsay/) or
+[`llm`](https://llm.datasette.io/en/stable/setup.html):
+
+```bash
+$ pipx install llm
+
+$ which llm
+/Users/jbranchaud/.local/bin/llm
+
+$ llm --version
+llm, version 0.13.1
+```

rails/get-formatted-utc-offset-value.md

@@ -0,0 +1,37 @@
+# Get Formatted UTC Offset Value
+
+The UTC offset (during DST) for Chicago is `-05:00`. And for Newfoundland it is
+`-02:30`.
+
+Rails has an [`ActiveSupport::TimeZone`
+module](https://api.rubyonrails.org/v7.1.3.2/classes/ActiveSupport/TimeZone.html#method-c-seconds_to_utc_offset)
+that can turn the UTC offset in seconds into this formatted value.
+
+```ruby
+> chicago = TZInfo::Timezone.get('America/Chicago')
+=> #<TZInfo::DataTimezone: America/Chicago>
+> ActiveSupport::TimeZone.seconds_to_utc_offset(chicago.utc_offset)
+=> "-05:00"
+
+> newfoundland = TZInfo::Timezone.get('America/St_Johns')
+=> #<TZInfo::DataTimezone: America/St_Johns>
+> ActiveSupport::TimeZone.seconds_to_utc_offset(newfoundland.utc_offset)
+=> "-02:30"
+```
+
+The underlying `tzinfo` gem is DST-aware and its database even knows which time
+zone identifiers don't observe DST, so you can run this anytime of the year and
+expect reliable results.
+
+Here is another way at this:
+
+```ruby
+> chicago = TZInfo::Timezone.get('America/Chicago')
+=> #<TZInfo::DataTimezone: America/Chicago>
+> ActiveSupport::TimeZone[chicago.name]
+=> #<ActiveSupport::TimeZone:0x00000001099d8140 @name="America/Chicago", @tzinfo=#<TZInfo::DataTimezone: America/Chicago>, @utc_offset=nil>
+> ActiveSupport::TimeZone[chicago.name].formatted_offset
+=> "-06:00"
+> ActiveSupport::TimeZone[chicago.name].formatted_offset(false)
+=> "-0600"
+```

rails/look-up-time-zone-info-for-identifier.md

@@ -0,0 +1,33 @@
+# Look Up Time Zone Info For Identifier
+
+The `ActiveSupport::TimeZone` class overrides the `#[]` method to be a lookup
+mechanism for IANA Time Zone Identifier strings. These are strings like
+`America/Chicago` (or anything else listed under `TZInfo::Timezone.all`).
+
+Let's get an instance for `America/Chicago`.
+
+```ruby
+> chi = ActiveSupport::TimeZone['America/Chicago']
+=> #<ActiveSupport::TimeZone:0x00000001099d8140
+ @name="America/Chicago",
+ @tzinfo=#<TZInfo::DataTimezone: America/Chicago>,
+ @utc_offset=nil>
+```
+
+Notice it has a `tzinfo` instance variable that we can access. That object
+contains all kinds of useful things.
+
+```ruby
+> chi.tzinfo.name
+=> "America/Chicago"
+> chi.tzinfo.friendly_identifier
+=> "America - Chicago"
+> chi.tzinfo.abbr
+=> "CDT"
+> chi.tzinfo.utc_offset
+=> -18000
+> chi.tzinfo.dst?
+=> true
+```
+
+All of these and more. Run `ls chi.tzinfo` in a `pry` session to see what else.

ruby/define-multiline-strings-with-heredocs.md

@@ -0,0 +1,47 @@
+# Define Multiline Strings With Heredocs
+
+[A _heredoc_ (_here document_) is a special ruby
+syntax](https://ruby-doc.org/core-2.5.0/doc/syntax/literals_rdoc.html#label-Here+Documents)
+for defining formatted multiline strings. These are useful for any situation
+where you need to define a block of text where newlines and indentation are
+preserved -- e.g. output an error, help message, or some formatted SQL.
+
+The standard syntax is defined with `<<` and some uppercase identifier (e.g.
+`TXT`, `DOC`, `SQL`, etc.) to open and close the multiline string.
+
+```ruby
+def lookup_team(team_id)
+  query = <<SQL
+    select users.id from users
+      join teams
+        on teams.id = users.team_id
+      where teams.id = #{team_id}
+      order by created_at desc
+      limit 10;
+SQL
+
+  team_member_ids = db.execute(query)
+end
+```
+
+With the SQL formatted this way, it is easier to read and we can print/log out
+this nicely formatted version to make debugging easier.
+
+Notice that the terminating `SQL` identifier is fully left justified. I find
+that visually off relative to the indentation of everything else, so I like to
+use the _indented_ heredoc syntax (`<<-`).
+
+```ruby
+def lookup_team(team_id)
+  query = <<-SQL
+    select users.id from users
+      join teams
+        on teams.id = users.team_id
+      where teams.id = #{team_id}
+      order by created_at desc
+      limit 10;
+  SQL
+
+  team_member_ids = db.execute(query)
+end
+```

ruby/get-utc-offset-for-different-time-zones.md

@@ -0,0 +1,42 @@
+# Get UTC Offset For Different Time Zones
+
+The [IANA Time Zone Database](https://www.iana.org/time-zones) uses identifiers
+like `America/Chicago`, `Asia/Hong_Kong`, `Africa/Nairobi`, etc. as specifiers
+for notable locations with time zone information.
+
+> Most timezones correspond to a notable location and the database records all
+> known clock transitions for that location; some timezones correspond instead
+> to a fixed UTC offset.
+—[Theory and pragmatics of the tz code and data](https://data.iana.org/time-zones/theory.html)
+
+These identifiers can be used to look up time zone details with the [`tzinfo`
+gem](https://github.com/tzinfo/tzinfo).
+
+Here is an example of passing one to the `#get` method and then getting the UTC
+offset in seconds.
+
+```ruby
+> require 'tzinfo'
+
+> mountain = TZInfo::Timezone.get('America/Denver')
+=> #<TZInfo::DataTimezone: America/Denver>
+> mountain.utc_offset
+=> -21600
+```
+
+We can even get the base UTC offset that doesn't account for DST:
+
+```ruby
+> moutain.base_utc_offset
+=> -25200
+```
+
+Notice, this is the same as the standard offset for a time zone like Phoenix
+that doesn't observe DST.
+
+```ruby
+> phoenix = TZInfo::Timezone.get('America/Phoenix')
+=> #<TZInfo::DataTimezone: America/Phoenix>
+> phoenix.utc_offset
+=> -25200
+```

vscode/find-the-location-of-user-settings-json-file.md

@@ -0,0 +1,31 @@
+# Find The Location Of User Settings JSON File
+
+There are a ton ways to customize and fine-tune VS Code. All of the settings
+have defaults which can then be customized on a workspace and user level.
+Typically you'll access these files within VS Code via the Command Palette. I
+was curious though: since it is just a JSON file, surely I can view and modify
+it with any editor.
+
+On a Mac, the user-level `settings.json` file is located at
+`~/Library/Application\ Support/Code/User/settings.json`.
+
+Open it up and you might see something like this:
+
+```json
+{
+  "editor.formatOnSave": true,
+  "editor.defaultFormatter": "esbenp.prettier-vscode",
+  "window.zoomLevel": 1,
+  "workbench.editor.showTabs": "single"
+}
+```
+
+A handful of settings with specific overrides.
+
+Feel free to edit what is in here or add other settings that you want to set.
+Just make sure you know what you're doing and that you set valid values.
+
+The VS Code docs list [the locations of these files on other operating
+systems](https://code.visualstudio.com/docs/getstarted/settings#_settings-file-locations).
+
+[source](https://stackoverflow.com/questions/53840644/location-of-vs-code-preferences)

workflow/access-1password-credential-from-cli.md

@@ -0,0 +1,29 @@
+# Access 1Password Credential From CLI
+
+With the `op` CLI, I can store things like API keys and secrets in my 1Password
+vault and then access them from the command line. This assumes I've already
+installed the CLI (`brew install 1password-cli`) and connected it to the
+1Password app via the _Developer_ settings.
+
+The `op item get` command takes a credential name and returns all the details
+for the entry with that _Title_. Here is how I can access my _Anthropic Claude
+API Key_ details.
+
+```bash
+$ op item get "Anthropic Claude API Key"
+```
+
+With the `--field` flag, I can grab a specific field, such as the `credential`,
+from that entry.
+
+```bash
+$ op item get "Anthropic Claude API Key" --field credential
+sk-ant-api03-abc......xyz
+```
+
+A command like this can be embedded in other commands as a way of referencing
+secrets without explicitly entering them into your shell history.
+
+```bash
+$ curl https://api -H "x-api-key: $(op item get "Anthropic Claude API Key" --field credential)" ...
+```