376 lines
16 KiB
Scala
Executable file
376 lines
16 KiB
Scala
Executable file
#!/usr/bin/env amm
|
|
import $ivy.`de.qwertyuiop::copret:0.0.1`
|
|
import de.qwertyuiop.copret._
|
|
import de.qwertyuiop.copret.syntax._
|
|
import TypedCommand.{interactive, shell => sh}, Format.figlet
|
|
|
|
import ammonite.ops.{given, *}
|
|
|
|
|
|
/* Configuration */
|
|
|
|
/* store paths for reuse.
|
|
* most of the commands in this presentation will be git commands in a demo repository, so the path to that repo is set
|
|
* as implicit (will be the working directory of executed commands) */
|
|
val imgs = pwd/"img"
|
|
given repoDir: Path= pwd/"demoRepo"
|
|
import de.qwertyuiop.copret.{given Theme}
|
|
|
|
/* You can define any variables and use then in your presentation.
|
|
* The presentation is pure Scala code, you can use anything that Scala offers . */
|
|
val debug = true
|
|
|
|
/* image height is defined by the iterm2 image protocol as follows:
|
|
* N: N character cells.
|
|
* Npx: N pixels.
|
|
* N%: N percent of the session's width or height.
|
|
* auto: The image's inherent size will be used to determine an appropriate dimension.
|
|
*
|
|
* The `Image` slide element will default to 100% height and width (preserving aspect ratio). Here the maximum height
|
|
* is calculated for slides with the default header (1 row status, 3 rows title font, 3 rows spacing)
|
|
*/
|
|
val imageHeight = (rows - 7).toString
|
|
|
|
/* Make sure, the demo repo is not there in the beginning. We'll create it in the presentation */
|
|
rm! repoDir
|
|
|
|
/* the basic building block of copret presentations is the various case classes of the `Slide` trait */
|
|
val titleSlide =
|
|
Group( // `Group` combines several `Slide` objects into one
|
|
Clear, // `Clear` clears the screen, so the next slide element starts at the top
|
|
Image(imgs/"git-logo.png", width = "10%"), // `Image` currently requires a terminal supporting `imgcat`
|
|
Paragraph( // `Paragraph` simply prints its text contents
|
|
s"""${figlet("git", "roman").block.blue}
|
|
|
|
|
|${"Wie man es benutzt und was in .git eigentlich passiert".centered.blue}
|
|
|
|
|
|${"-- Alexander Gehrke".right(10)}
|
|
|""".stripMargin)
|
|
// Above you see some of the extension methods for strings, `block` for centering multiline text, `centered` for
|
|
// single lines, `right(10)` for placing text 10 spaces away from the right border and `blue` for coloring.
|
|
// also, `figlet` calls the external figlet command to render ASCII art text with the given font.
|
|
)
|
|
|
|
/* copret templates are simply normal methods that return slides */
|
|
def chapter(title: String, subtitle: String): Group = chapter(title, "", subtitle)
|
|
def chapter(title1: String, title2: String, subtitle: String): Group = {
|
|
val font = if((title1.length max title2.length) < columns / 10) "mono12" else "mono9"
|
|
Group(Clear,
|
|
header, // a built in template
|
|
Paragraph(
|
|
figlet(title1, font).block.green ++ figlet(title2, font).block.green ++ "\n" ++ subtitle.right(10).green
|
|
)
|
|
)
|
|
}
|
|
|
|
|
|
val parentSHApattern = raw"parent ([a-f0-9]{40})".r
|
|
val treeSHApattern = raw"tree ([a-f0-9]{40})".r
|
|
val blobSHApattern = raw"blob ([a-f0-9]{40})".r
|
|
|
|
/* With `prepare` you can define variables for a slide, that are computed when the presentation reaches the
|
|
* slide using it. This is useful for running external commands when a specific slide is reached and using their
|
|
* output (if you'd include them in the string interpolation directly, they'd run before starting the presentation).
|
|
*
|
|
* The code given to `prepare` is run exactly once *per slide using it*. See the usages of `gitHashes` below for
|
|
* details. */
|
|
case class GitHashes(commit: String, tree: String, blob: String, parent: String, subtree: String)
|
|
val gitHashes = prepare {
|
|
val commitSHA = %%%("git", "show-ref").substring(0,40)
|
|
val commit = %%%("git", "cat-file", "-p", "HEAD")
|
|
val treeSHA = treeSHApattern.findFirstMatchIn(commit).map(_.group(1)).getOrElse("")
|
|
val parentSHA = parentSHApattern.findFirstMatchIn(commit).map(_.group(1)).getOrElse("")
|
|
val tree = %%%("git", "cat-file", "-p", treeSHA)
|
|
val blobSHA = blobSHApattern.findFirstMatchIn(tree).map(_.group(1)).getOrElse("")
|
|
val subtreeSHA = treeSHApattern.findFirstMatchIn(tree).map(_.group(1)).getOrElse("")
|
|
GitHashes(commitSHA, treeSHA, blobSHA, parentSHA, subtreeSHA)
|
|
}
|
|
|
|
def gitStatus = TypedCommand("git", "status")
|
|
def gitCatFile(ref: String) = TypedCommand("git", "cat-file", "-p", ref)
|
|
|
|
def gitLogGraph(cutOff: Int = 0) = {
|
|
val shownCmd = "git log --graph --oneline --all"
|
|
val execCmd = shownCmd + " --decorate=short --color=always " + (if(cutOff > 0) "| head -n -" + cutOff else "")
|
|
val typer = sh(execCmd) showing shownCmd
|
|
if(cutOff > 0)
|
|
Group(typer, "...".text)
|
|
else
|
|
typer
|
|
}
|
|
|
|
/* A `Presentation` object can include a map of metadata. Which keys are used, depends on your used templates.
|
|
* To use them in a slide yourself (or for creating own templates), use the Meta slide class, which can access the
|
|
* presentation object and state to generate a slide.
|
|
*
|
|
* The only keys used in the packaged templates are currently "author" and "title" in the `header` template */
|
|
val meta = Map(
|
|
"author" -> "Alexander Gehrke",
|
|
"title" -> "Git"
|
|
)
|
|
|
|
/* A presentation consists of a `Vector[Slide]`. After each slide in this vector, the presentation pauses and waits for
|
|
* input. `Group` is used, to display several slides at once, and `PauseKey` can be used inside a `Group` to wait for
|
|
* input (but limited to displaying the rest of the `Group`, normal navigation is only possible between top level
|
|
* slides).
|
|
*
|
|
* Navigation distinguishes between normal and "quick" steps, the latter disables things like pauses or animations. It
|
|
* is also possible to jump to a specific slide.
|
|
* */
|
|
val presentation = Presentation(Vector(
|
|
titleSlide,
|
|
/* for simple slides, the `markdown` template and `IncludeMarkdown` Slide allow including plain markdown files.
|
|
* (currently requires mdcat) */
|
|
markdown("Wozu braucht man das?", pwd/"slides"/"01wozu.md"),
|
|
chapter("Basics", "Grundlegende Befehle"),
|
|
/* `slide` is a template for a `Group` with an optional title, that clears the screen */
|
|
slide("Basics")(
|
|
"""Git trackt Inhalt von Dateien innerhalb eines Repositories.
|
|
|Kann in neuem oder bestehenden Ordner angelegt werden
|
|
|""".par,
|
|
/* the `---` template displays a yellow line */
|
|
---,
|
|
/* `Pause` waits for the given number of milliseconds */
|
|
Pause(500),
|
|
/* `TypedCommand.shell` (here aliased to `sh`) displays a typing animation of that command and then executes it,
|
|
* showing its output in the presentation */
|
|
sh("git init demoRepo")(using pwd),
|
|
/* sometimes it's useful to display something else than is actually executed, e.g. to add comments, or to hide
|
|
* options only required because we don't call from an interactive shell (stuff like --color) */
|
|
sh("ls -1a --color=always demoRepo")(using pwd) showing "ls -1a demoRepo",
|
|
/* If you need to run commands that should not display anything in the presentation, use `Silent`.
|
|
* Here I use it to prepare the repository, but it could also be used e.g. for playing a sound or opening a video.*/
|
|
Silent {
|
|
%%%("git", "config", "user.email", "crater2150@example.com")
|
|
%%%("git", "config", "user.name", "crater2150")
|
|
%%%("git", "config", "color.status", "always")
|
|
%%%("git", "config", "color.ui", "always")
|
|
}
|
|
),
|
|
slide("Basics")(
|
|
"Noch ist das Repo leer. Ändern wir das:".par,
|
|
---,
|
|
Pause(500),
|
|
TypedCommand.fake("cd demoRepo"),
|
|
sh("echo 'Hello, World!' > hello.txt"),
|
|
Pause(500),
|
|
sh("ls -1a")
|
|
),
|
|
slide("Basics")(
|
|
"Den Zustand des Repos sehen wir mit `git status`\n".par,
|
|
---,
|
|
Pause(500),
|
|
gitStatus,
|
|
),
|
|
slide("Basics")(
|
|
"Damit Git Dateien trackt, müssen diese mit `git add` hinzugefügt werden.\n".par,
|
|
---,
|
|
sh("git add hello.txt"),
|
|
gitStatus,
|
|
),
|
|
slide("Basics")(
|
|
"""Die gespeicherten Zustände eines Repos nennt man Commit.
|
|
|Zu jedem Commit gibt man eine Zusammenfassung der Änderungen an
|
|
|""".par,
|
|
---,
|
|
Pause(500),
|
|
sh("git commit --message \"Added first file\""),
|
|
PauseKey,
|
|
---,
|
|
"""Commits werden über ihren SHA1-Hash identifiziert. Dieser wird ggf. abgekürzt.
|
|
|Mit `git log` können wir uns die bisherigen Commits ansehen:
|
|
|""".par,
|
|
---,
|
|
sh("git log")
|
|
),
|
|
/* here we see `gitHashes`, created with `prepare`, in action:
|
|
* As the code is run exactly once per `useIn` call i.e. per using slide, the hashes of the latest commit, tree and
|
|
* parent in the demo repo, that `gitHashes` retrieves, are always the ones for the repository state matching the
|
|
* slide. The prepared code is run and its result cached, when the slide is first displayed (or skipped over).
|
|
*/
|
|
gitHashes useIn { sha => slide("Was passiert bei einem Commit?")(
|
|
s"""Schauen wir uns an, was Git aus dem Commit gemacht hat.
|
|
|`git cat-file $$ref` zeigt Inhalt von Git-Objekten. `$$ref` ist Referenz des Objekts, z.B. der Hash.
|
|
|Unser Commit hatte den Hash `${sha.commit}`.
|
|
|Statt diesem geht auch `HEAD` = aktueller Commit.
|
|
|""".par,
|
|
---,
|
|
gitCatFile("HEAD"),
|
|
PauseKey,
|
|
---,
|
|
s"""Zum Hashen wird vor den Inhalt noch `<Objekttyp> <Länge des Inhalts in bytes\\0` gehängt.
|
|
|Hier: `Objekttyp == commit`
|
|
|""".par,
|
|
)},
|
|
gitHashes useIn { sha => slide("Commits, Trees, Blobs")(
|
|
s"""Neben den Metadaten ist in unserem Commit noch eine Zeile
|
|
| `tree ${sha.tree}`
|
|
|
|
|
|Trees repräsentieren Verzeichnisse, Tree in einem Commit = Wurzelverzeichnis des Repos
|
|
|`$$ref^{tree}` = Baum mit Referenz `$$ref`, oder wenn `$$ref` ein Commit ist, der Tree aus diesem
|
|
|""".par,
|
|
---,
|
|
gitCatFile("HEAD^{tree}"),
|
|
PauseKey,
|
|
---,
|
|
s"""Hier ist noch nicht viel zu sehen, da wir nur eine Datei haben.
|
|
|Einträge im Tree haben das Format:
|
|
| `<berechtigungen> <blob | tree> <sha1 hash> <dateiname>`
|
|
|""".par
|
|
)},
|
|
gitHashes useIn { sha => slide("Commits, Trees, Blobs")(
|
|
s"""Blobs sind die eigentlichen Dateiinhalte.
|
|
|Unsere `hello.txt` hat, wie im Tree zu sehen, den Hash ${sha.blob.substring(0,8)}…
|
|
|""".par,
|
|
---,
|
|
gitCatFile(sha.blob.substring(0,8)),
|
|
)},
|
|
slide("Commits, Trees, Blobs")(
|
|
s"""Fügen wir ein paar weitere Dateien und einen Unterordner hinzu
|
|
|""".par,
|
|
---,
|
|
sh("mkdir folder"),
|
|
sh("echo 'My other file' > other.txt"),
|
|
sh("echo 'File in folder' > folder/file.txt"),
|
|
sh("git add other.txt folder"),
|
|
sh("git commit -m 'Added more files'")
|
|
),
|
|
/* when this slide is reached, our commit hashes have changed. All the previous slides will still display the old ones */
|
|
gitHashes useIn { sha => slide("Commits, Trees, Blobs")(
|
|
s"""Wie sieht der neue Commit aus?
|
|
|""".par,
|
|
---,
|
|
gitCatFile("HEAD"),
|
|
---,
|
|
PauseKey,
|
|
s"""Wir haben eine neue Art von Eintrag:
|
|
| `parent ${sha.parent}`
|
|
|
|
|
|Dieser verweist auf den vorherigen Commit.
|
|
|Durch solche Verweise bilden alle Commits einen gerichteten Graphen.
|
|
|""".par
|
|
)},
|
|
gitHashes useIn { sha => slide("Commits, Trees, Blobs")(
|
|
s"""Sehen wir uns den neuen Tree an:
|
|
|""".par,
|
|
gitCatFile("HEAD^{tree}"),
|
|
---,
|
|
s"""Eine unserer neuen Dateien ist zu sehen.
|
|
|Auch `hello.txt` ist noch da, mit selbem Hash wie vorher (da nicht geändert)
|
|
|Die andere neue Datei ist im Verzeichnis `folder`, und daher im `tree` mit dem Hash `${sha.subtree.substring(0,8)}…` :
|
|
|""".par,
|
|
gitCatFile(sha.subtree.substring(0,8)),
|
|
)},
|
|
slide("Git als Graph")(Image(imgs/"repo-graph.png", height=imageHeight)),
|
|
slide("Dateien editieren")(
|
|
s"""Auch Änderungen an schon getrackten Dateien müssen mit `git add` zum Repo hinzugefügt werden.
|
|
|Erlaubt es, nur Teile der Änderungen zu committen und dadurch commits zu unterteilen.
|
|
|Ändern wir ein paar Dateien:
|
|
|""".par,
|
|
PauseKey,
|
|
Group(
|
|
interactive("vim", "hello.txt").replaceIf(debug)(sh("echo 'New line' >> hello.txt")),
|
|
interactive("vim", "folder/file.txt").replaceIf(debug)(sh("echo 'New line' >> folder/file.txt")),
|
|
gitStatus,
|
|
),
|
|
),
|
|
slide("Dateien editieren")(
|
|
sh("git add folder/file.txt; git status"),
|
|
---,
|
|
s"""`git status` zeigt, welche Änderungen in den nächsten Commit aufgenommen werden.
|
|
|Solche bezeichnet man als "staged" oder "im Stagingbereich".
|
|
|Auch zu sehen: Befehle um diese zu modifizieren (`git add` / `git restore --staged`).
|
|
|`git restore <file>` (ohne `--staged`) verwirft Änderungen → Nicht wieder herstellbar!
|
|
|""".par,
|
|
),
|
|
slide("Dateien editieren")(
|
|
sh("git commit -m \"Modified file in folder\""),
|
|
sh("git add hello.txt; git commit -m \"Extended greeting\""),
|
|
gitStatus,
|
|
),
|
|
markdown("Was bisher geschah", pwd/"slides"/"02summary.md"),
|
|
chapter("Branches", "Grundlegende Befehle"),
|
|
slide("\n".par, IncludeMarkdown(pwd/"slides"/"02branches.md")),
|
|
slide("Branches")(
|
|
sh("git branch"),
|
|
---,
|
|
prepare { %%%("git", "branch", "--show-current").trim } useIn { branch =>
|
|
s"Aktuell sind wir auf dem Branch `$branch` und es gibt keine weiteren Branches\n".par
|
|
},
|
|
PauseKey,
|
|
s"""Neuen Branch anlegen mit `git branch <name>`
|
|
|Alternativ: Branch anlegen und direkt auf diesen wechseln mit `git switch -c <name>`
|
|
|""".par,
|
|
---,
|
|
sh("git switch -c feature/foo"),
|
|
sh("git branch"),
|
|
),
|
|
slide("Branches")(
|
|
"Machen wir ein paar Änderungen und committen sie:\n".par,
|
|
---,
|
|
sh("echo 'a new line' >> hello.txt") showing "echo 'a new line' >> hello.txt # appends to hello.txt",
|
|
sh("git add hello.txt"),
|
|
sh("git commit -m \"Added line to hello\""),
|
|
---,
|
|
"Da der Branch `feature/foo` aktiv war, zeigt dieser auf den neuen Commit. `master` wird nicht geändert:".code.text,
|
|
PauseKey,
|
|
sh("git log --graph --oneline --all --decorate=short --color=always") showing "git log --graph --oneline --all",
|
|
),
|
|
slide("Branches")(
|
|
"Jetzt wechseln wir zurück zu `master`:\n".par,
|
|
---,
|
|
sh("git switch master"),
|
|
sh("echo 'Also a new line' >> other.txt"),
|
|
sh("git add other.txt"),
|
|
sh("git commit -m \"Added line to other\""),
|
|
gitLogGraph(),
|
|
),
|
|
slide("Branches")(
|
|
"Im Prinzip haben wir einfach zwei Commits mit dem selben `parent` hinzugefügt:".code.text,
|
|
---,
|
|
gitCatFile("master"),
|
|
gitCatFile("feature/foo"),
|
|
),
|
|
slide("Merges")(
|
|
"""Im Normalfall möchte man mehrere Branches irgendwann wieder zusammenführen.
|
|
|Dazu gibt es den Befehl `merge`:""".par,
|
|
---,
|
|
sh("git merge feature/foo"),
|
|
gitLogGraph(2),
|
|
),
|
|
slide("Merge Commits")(
|
|
"Um zwei divergierte Branches zusammenzuführen, gibt es Merge Commits mit mehreren `parent` Einträgen:".code.text,
|
|
---,
|
|
gitCatFile("master"),
|
|
),
|
|
slide("Merge Konflikte")(
|
|
"Was passiert, wenn wir nicht kompatible Änderungen haben? Noch mal vom Zustand vor dem Merge aus, auf `master`:".code.text,
|
|
Silent {
|
|
%%%("git", "update-ref", "refs/heads/master", "feature/foo~")
|
|
},
|
|
---,
|
|
sh("echo 'a different line' >> hello.txt"),
|
|
sh("git add hello.txt"),
|
|
sh("git commit -m \"Added different line to hello\""),
|
|
gitLogGraph(),
|
|
),
|
|
slide("Der Object Store")(
|
|
"""Git speichert Objekte unter `.git/objects/<erste zwei Stellen vom Hash>/<Rest vom Hash>`
|
|
|Objekte sind komprimiert.
|
|
|""".par,
|
|
sh("tree -C .git/objects/ | head -n 11") showing "tree .git/objects/",
|
|
s"...".par,
|
|
),
|
|
), meta=meta)
|
|
|
|
/* When starting the presentation, you can pass a custom keymap to use.
|
|
* The `runForeground` action lets you run any command, interrupting the presentation until it exits.
|
|
* Here I bind the 'i' key to open tmux in the demo repo, for having interactive access, so I can call additional git
|
|
* commands for questions */
|
|
presentation.start(using Keymap.default ++ Map(
|
|
Key('i') -> SlideAction.runForeground("tmux"),
|
|
))
|
|
|
|
|
|
/* vim:set tw=120: */
|