Use Dune to generate OPAM package definitions (#1191)

This patch moves the definitions of our OPAM packages into the file `dune-project`. The OPAM package definitions are automatically generated from this file. This approach offers some advantages:

* Less redundancy: package descriptions are now shared.
* Dune integration: OPAM package definitions are kept in sync with dune.
* Versioning: `dune-release` automatically versions the OPAM package definitions.

Our build rules for the `links` package are a little more complicated than `dune` supports out-of-the-box. The steps required to build this package are defined in the `links.opam.template` file, which `dune` automatically pastes into the generated `links.opam` file.

I fixed the minimum required version of OCaml to `4.14.0`, as that seems to be the minimum version with which Links compiles at the moment.

dune-project

@@ -1,4 +1,104 @@
 (lang dune 2.7)
-(using menhir 2.0)
-(name links)
-(implicit_transitive_deps false)
+;; dune language version (NOTE this comment applies to the above line; it is intentionally placed here!)
+(using menhir 2.0)                 ;; enable use of menhir
+(name links)                       ;; package name
+(implicit_transitive_deps false)   ;; hides transitive dependencies in libraries/executables/tests
+(generate_opam_files true)         ;; generate .opam package files using the descriptions defined in this file
+
+
+;;
+;; Project metainformation
+;;
+
+(source
+ (github links-lang/links))
+(homepage
+  https://links-lang.org)
+(authors
+  "The Links Team <[email protected]>")
+(maintainers
+  "Daniel Hillerström <[email protected]>")
+(license
+  GPL-3.0-only)
+(documentation
+  "https://links-lang.org/quick-help.html")
+
+;;
+;; The Links Programmming System
+;;
+
+(package
+ (name links)
+ (synopsis "The Links Programming Language")
+ (description "Links is a functional programming language designed to make web programming easier.")
+ (depends (ocaml (>= : 4.14.0))
+          (dune-configurator (>= : 3.8))
+           ppx_deriving
+          (ppx_deriving_yojson (>= 3.3))
+           base64
+           linenoise
+           ANSITerminal
+          (lwt (>= 5.0.0))
+           cohttp
+           cohttp-lwt
+           cohttp-lwt-unix
+           conduit-lwt-unix
+           uri
+           tls
+           websocket
+           websocket-lwt-unix
+           safepass
+           result
+           ocamlfind
+          (menhir (>= 20210419))
+          (ppx_sexp_conv (>= v0.16.0))
+          (calendar (>= 2.0.4))
+          (rdf_lwt (>= 0.13.0)))
+ (tags
+  ("web programming" "tierless" "multi-tier" "effect handlers" "effect typing" "session types"
+   "concurrency" "webpage" "extensible data types" "language-integrated queries")))
+
+;;
+;; Links PostgreSQL driver
+;;
+
+(package
+ (name links-postgresql)
+ (synopsis "Postgresql database driver for the Links Programming Language")
+ (description "Postgresql database driver for the Links Programming Language")
+ (depends (links (= :version))
+          postgresql)
+ (tags
+   ("postgresql" "database")))
+
+;;
+;; Links SQLite3 driver
+;;
+
+(package
+ (name links-sqlite3)
+ (synopsis "SQLite database driver for the Links Programming Language")
+ (description "SQLite database driver for the Links Programming Language")
+ (depends (links (= :version))
+          sqlite3)
+ (tags
+   ("sqlite" "database")))
+
+;;
+;; Links MySQL driver
+;;
+
+(package
+ (name links-mysql)
+ (synopsis "MySQL database driver for the Links Programming Language")
+ (description "MySQL database driver for the Links Programming Language")
+ (depends (links (= :version))
+          conf-mysql
+          mysql8)
+ (tags
+   ("mysql" "database")))
+
+
+
+; See the complete stanza docs at https://dune.readthedocs.io/en/stable/dune-files.html#dune-project
+

links-mysql.opam

@@ -1,22 +1,33 @@
+# This file is generated by dune, edit dune-project instead
 opam-version: "2.0"
-maintainer: "James Cheney <[email protected]>"
-authors: "The Links Team <[email protected]>"
 synopsis: "MySQL database driver for the Links Programming Language"
 description: "MySQL database driver for the Links Programming Language"
-homepage: "https://github.com/links-lang/links"
-dev-repo: "git+https://github.com/links-lang/links.git"
-bug-reports: "https://github.com/links-lang/links/issues"
+maintainer: ["Daniel Hillerström <[email protected]>"]
+authors: ["The Links Team <[email protected]>"]
 license: "GPL-3.0-only"
-
-build: [
-  [ "dune" "subst" ] {dev}
-  [ "dune" "build" "-p" name "-j" jobs ]
-]
-
+tags: ["mysql" "database"]
+homepage: "https://links-lang.org"
+doc: "https://links-lang.org/quick-help.html"
+bug-reports: "https://github.com/links-lang/links/issues"
 depends: [
-  "ocaml" {>= "4.08.0"}
   "dune" {>= "2.7"}
+  "links" {= version}
   "conf-mysql"
   "mysql8"
-  "links" {= version}
+  "odoc" {with-doc}
 ]
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
+]
+dev-repo: "git+https://github.com/links-lang/links.git"

links-postgresql.opam

@@ -1,22 +1,32 @@
+# This file is generated by dune, edit dune-project instead
 opam-version: "2.0"
-maintainer: "Daniel Hillerström <[email protected]>"
-authors: "The Links Team <[email protected]>"
 synopsis: "Postgresql database driver for the Links Programming Language"
 description: "Postgresql database driver for the Links Programming Language"
-homepage: "https://github.com/links-lang/links"
-dev-repo: "git+https://github.com/links-lang/links.git"
-bug-reports: "https://github.com/links-lang/links/issues"
+maintainer: ["Daniel Hillerström <[email protected]>"]
+authors: ["The Links Team <[email protected]>"]
 license: "GPL-3.0-only"
-
-
-build: [
-  [ "dune" "subst" ] {dev}
-  [ "dune" "build" "-p" name "-j" jobs ]
-]
-
+tags: ["postgresql" "database"]
+homepage: "https://links-lang.org"
+doc: "https://links-lang.org/quick-help.html"
+bug-reports: "https://github.com/links-lang/links/issues"
 depends: [
-  "ocaml" {>= "4.08.0"}
   "dune" {>= "2.7"}
-  "postgresql"
   "links" {= version}
+  "postgresql"
+  "odoc" {with-doc}
 ]
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
+]
+dev-repo: "git+https://github.com/links-lang/links.git"

links-sqlite3.opam

@@ -1,21 +1,32 @@
+# This file is generated by dune, edit dune-project instead
 opam-version: "2.0"
-maintainer: "Daniel Hillerström <[email protected]>"
-authors: "The Links Team <[email protected]>"
 synopsis: "SQLite database driver for the Links Programming Language"
 description: "SQLite database driver for the Links Programming Language"
-homepage: "https://github.com/links-lang/links"
-dev-repo: "git+https://github.com/links-lang/links.git"
-bug-reports: "https://github.com/links-lang/links/issues"
+maintainer: ["Daniel Hillerström <[email protected]>"]
+authors: ["The Links Team <[email protected]>"]
 license: "GPL-3.0-only"
-
-build: [
-  [ "dune" "subst" ] {dev}
-  [ "dune" "build" "-p" name "-j" jobs ]
-]
-
+tags: ["sqlite" "database"]
+homepage: "https://links-lang.org"
+doc: "https://links-lang.org/quick-help.html"
+bug-reports: "https://github.com/links-lang/links/issues"
 depends: [
-  "ocaml" {>= "4.08.0"}
   "dune" {>= "2.7"}
-  "sqlite3"
   "links" {= version}
+  "sqlite3"
+  "odoc" {with-doc}
 ]
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
+]
+dev-repo: "git+https://github.com/links-lang/links.git"

links.opam

@@ -1,22 +1,30 @@
+# This file is generated by dune, edit dune-project instead
 opam-version: "2.0"
-maintainer: "Daniel Hillerström <[email protected]>"
-authors: "The Links Team <[email protected]>"
 synopsis: "The Links Programming Language"
-description: "Links is a functional programming language designed to make web programming easier."
-homepage: "https://github.com/links-lang/links"
-dev-repo: "git+https://github.com/links-lang/links.git"
-bug-reports: "https://github.com/links-lang/links/issues"
+description:
+  "Links is a functional programming language designed to make web programming easier."
+maintainer: ["Daniel Hillerström <[email protected]>"]
+authors: ["The Links Team <links-[email protected]>"]
 license: "GPL-3.0-only"
-
-
-build: [
-  [ "dune" "exec" "preinstall/preinstall.exe" "--" "-libdir" _:lib ]
-  [ make "opam-build-links.opam" ]
+tags: [
+  "web programming"
+  "tierless"
+  "multi-tier"
+  "effect handlers"
+  "effect typing"
+  "session types"
+  "concurrency"
+  "webpage"
+  "extensible data types"
+  "language-integrated queries"
 ]
-
+homepage: "https://links-lang.org"
+doc: "https://links-lang.org/quick-help.html"
+bug-reports: "https://github.com/links-lang/links/issues"
 depends: [
-  "ocaml" {>= "4.08.0"}
   "dune" {>= "2.7"}
+  "ocaml" { >= "4.14.0"}
+  "dune-configurator" { >= "3.8"}
   "ppx_deriving"
   "ppx_deriving_yojson" {>= "3.3"}
   "base64"
@@ -38,4 +46,10 @@ depends: [
   "ppx_sexp_conv" {>= "v0.16.0"}
   "calendar" {>= "2.0.4"}
   "rdf_lwt" {>= "0.13.0"}
+  "odoc" {with-doc}
+]
+dev-repo: "git+https://github.com/links-lang/links.git"
+build: [
+  [ "dune" "exec" "preinstall/preinstall.exe" "--" "-libdir" _:lib ]
+  [ make "opam-build-links.opam" ]
 ]

links.opam.template

@@ -0,0 +1,4 @@
+build: [
+  [ "dune" "exec" "preinstall/preinstall.exe" "--" "-libdir" _:lib ]
+  [ make "opam-build-links.opam" ]
+]