Add (and run) script to auto-regenerate permalink redirects.

This deliberately doesn't make any changes in the current formatting
or targets (yet); that can come later.  It uses the existing yaml
format and file.

4 files changed, 138 insertions, 4 deletions

diff --git a/mdbook/spec/book.toml b/mdbook/spec/book.toml
index ee858a8..ee46350 100644
--- a/mdbook/spec/book.toml
+++ b/mdbook/spec/book.toml
@@ -32,7 +32,7 @@ build-dir = "../../html"
 "/pt-spec/index.html" = "https://gitweb.torproject.org/torspec.git/tree/pt-spec.txt"
 "/rend-spec/index.html" = "https://gitweb.torproject.org/torspec.git/tree/rend-spec-v3.txt"
 "/rend-spec-v2" = "https://gitweb.torproject.org/torspec.git/tree/attic/rend-spec-v2.txt"
-"/rend-spec-v3/index.html" = "https://gitweb.torproject.org/torspec.git/tree/rend-spec-v3.txt"
+"/rend-spec-v3" = "https://gitweb.torproject.org/torspec.git/tree/rend-spec-v3.txt"
 "/socks-extensions" = "https://gitweb.torproject.org/torspec.git/tree/socks-extensions.txt"
 "/srv-spec/index.html" = "https://gitweb.torproject.org/torspec.git/tree/srv-spec.txt"
 "/tor-fw-helper-spec" = "https://gitweb.torproject.org/torspec.git/tree/attic/tor-fw-helper-spec.txt"
diff --git a/mdbook/spec/make_redirects.py b/mdbook/spec/make_redirects.py
new file mode 100755
index 0000000..c582505
--- /dev/null
+++ b/mdbook/spec/make_redirects.py
@@ -0,0 +1,58 @@
+#!/usr/bin/env python3
+
+import yaml, os, re, sys
+
+def update_file(fname, start_marker, end_marker, replacement):
+    content = list(open(fname, 'r').readlines())
+    startline = content.index(start_marker)
+    endline = content.index(end_marker)
+    assert endline > startline
+    content[startline+1:endline] = replacement
+
+    with open(fname+".tmp", 'w') as f:
+        f.write("".join(content))
+    os.rename(fname+".tmp", fname)
+
+BOOK_START = "# BEGIN AUTO-GENERATED REDIRECTS\n"
+BOOK_END = "# END AUTO-GENERATED REDIRECTS\n"
+
+README_START = "<!-- BEGIN AUTO-GENERATED REDIRECTS -->\n"
+README_END = "<!-- END AUTO-GENERATED REDIRECTS -->\n"
+
+def book_redirects(rs, spec_dir):
+    lines = []
+    for kwd, info in rs.items():
+        if os.path.isdir(os.path.join(spec_dir, kwd)):
+            source = kwd + "/index.html"
+        else:
+            source = kwd
+        target = info['target']
+        lines.append(
+            f'"/{source}" = "{target}"\n'
+        )
+    return "".join(lines)
+
+def readme_redirects(rs):
+    lines = [ "<dl>\n" ]
+    for kwd, info in rs.items():
+        target = info['target']
+        desc = info['description']
+        lines.append(f'<dt><a href="/{kwd}"><code>/{kwd}</code></a></dt>\n')
+        lines.append(f'<dd><a href="{target}"><code>{target}</code> ({desc})</a></dt>\n')
+
+    lines.append("</dl>\n")
+    return "".join(lines)
+
+if __name__ == '__main__':
+    toplevel = os.path.join(os.path.dirname(sys.argv[0]), "..", "..")
+    book_fname = os.path.join(toplevel, "mdbook", "spec", "book.toml")
+    spec_dir = os.path.join(toplevel, "spec")
+    readme_fname = os.path.join(toplevel, "spec", "README.md")
+    yaml_fname = os.path.join(toplevel, "mdbook", "spec", "spec-redirects.yaml")
+
+    rs = yaml.load(open(yaml_fname), yaml.Loader)['redirects']
+
+    update_file(book_fname, BOOK_START, BOOK_END, book_redirects(rs, spec_dir))
+    update_file(readme_fname, README_START, README_END, readme_redirects(rs))
+
+
diff --git a/mdbook/spec/spec-redirects.yaml b/mdbook/spec/spec-redirects.yaml
new file mode 100644
index 0000000..26310a7
--- /dev/null
+++ b/mdbook/spec/spec-redirects.yaml
@@ -0,0 +1,79 @@
+# yamllint disable rule:line-length
+---
+# NOTE: that this file is for permalink redirects only.  If you want a
+# temporary redirect, or a redirect that is not a documentated
+# permanent link, do not add it here!
+
+redirects:
+  'address-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/address-spec.txt
+    description: Special Hostnames in Tor
+  'bandwidth-file-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/bandwidth-file-spec.txt
+    description: Directory Authority Bandwidth File spec
+  'bridgedb-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/bridgedb-spec.txt
+    description: BridgeDB specification
+  'cert-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/cert-spec.txt
+    description: Ed25519 certificates in Tor
+  'collector-protocol':
+    target: https://gitweb.torproject.org/collector.git/tree/src/main/resources/docs/PROTOCOL
+    description: Protocol of CollecTor's File Structure
+  'control-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/control-spec.txt
+    description: Tor control protocol, version 1
+  'dir-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/dir-spec.txt
+    description: Tor directory protocol, version 3
+  'dir-list-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/dir-list-spec.txt
+    description: Tor Directory List file format
+  'ext-orport-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/ext-orport-spec.txt
+    description: Extended ORPort for pluggable transports
+  'gettor-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/gettor-spec.txt
+    description: GetTor specification
+  'padding-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/padding-spec.txt
+    description: Tor Padding Specification
+  'path-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/path-spec.txt
+    description: Tor Path Specification
+  'pt-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/pt-spec.txt
+    description: Tor Pluggable Transport Specification, version 1
+  'rend-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/rend-spec-v3.txt
+    description: Tor Onion Service Rendezvous Specification, Version 2
+  'rend-spec-v2':
+    target: https://gitweb.torproject.org/torspec.git/tree/attic/rend-spec-v2.txt
+    description: Tor Onion Service Rendezvous Specification, Version 2
+  'rend-spec-v3':
+    target: https://gitweb.torproject.org/torspec.git/tree/rend-spec-v3.txt
+    description: Tor Onion Service Rendezvous Specification, Version 3
+  'socks-extensions':
+    target: https://gitweb.torproject.org/torspec.git/tree/socks-extensions.txt
+    description: "Tor's extensions to the SOCKS protocol"
+  'srv-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/srv-spec.txt
+    description: Tor Shared Random Subsystem Specification
+  'tor-fw-helper-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/attic/tor-fw-helper-spec.txt
+    description: "Tor's (little) Firewall Helper specification"
+  'tor-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/tor-spec.txt
+    description: Tor Protocol Specification
+  'torbrowser-design':
+    target: https://2019.www.torproject.org/projects/torbrowser/design/
+    description: The Design and Implementation of the Tor Browser
+  'version-spec':
+    target: https://gitweb.torproject.org/torspec.git/tree/version-spec.txt
+    description: How Tor Version Numbers Work
+  'tor-design':
+    target: https://svn.torproject.org/svn/projects/design-paper/tor-design.pdf
+    description: "Tor: The Second-Generation Onion Router"
+  'walking-onions':
+    target: https://github.com/nmathewson/walking-onions-wip/tree/master/specs
+    description: Walking Onions specifications (work in progress)
diff --git a/spec/README.md b/spec/README.md
index 1aff087..3439afe 100644
--- a/spec/README.md
+++ b/spec/README.md
@@ -94,7 +94,6 @@ long-term permalinks.
 > The `gitweb.torproject.org` site is currently deprecated.
 
 <!-- BEGIN AUTO-GENERATED REDIRECTS -->
-
 <dl>
 <dt><a href="/address-spec"><code>/address-spec</code></a></dt>
 <dd><a href="https://gitweb.torproject.org/torspec.git/tree/address-spec.txt"><code>https://gitweb.torproject.org/torspec.git/tree/address-spec.txt</code> (Special Hostnames in Tor)</a></dt>
@@ -144,9 +143,7 @@ long-term permalinks.
 <dd><a href="https://svn.torproject.org/svn/projects/design-paper/tor-design.pdf"><code>https://svn.torproject.org/svn/projects/design-paper/tor-design.pdf</code> (Tor: The Second-Generation Onion Router)</a></dt>
 <dt><a href="/walking-onions"><code>/walking-onions</code></a></dt>
 <dd><a href="https://github.com/nmathewson/walking-onions-wip/tree/master/specs"><code>https://github.com/nmathewson/walking-onions-wip/tree/master/specs</code> (Walking Onions specifications (work in progress))</a></dt>
-
 </dl>
-
 <!-- END AUTO-GENERATED REDIRECTS -->
 
 [git repository]: https://gitlab.torproject.org/tpo/core/torspec/