(core) new library(openpg): open a file in the playground

Src-commit: 6bbc27c98ef682920e6b2f001339f900f36ab5f6

Author: jfmc

core/library/openpg.pl

@@ -0,0 +1,70 @@
+:- module(openpg, [], [assertions, regtypes, fsyntax]).
+
+:- doc(title, "Open a Ciao playground").
+:- doc(author, "The Ciao Development Team").
+
+:- doc(module, "This module provides predicates to open documents
+   using the Ciao Playground. It relies on @lib{opendoc} to open
+   arbritrary URLs.
+
+   This is just a small client library. The playground code is
+   distributed seperately in the @tt{ciao_playground} bundle.
+").
+
+:- use_module(library(opendoc)).
+:- use_module(library(streams), [fixed_absolute_file_name/3]).
+
+:- export(pgloc/1).
+:- regtype pgloc/1 # "Ciao Playground location:
+@begin{itemize}
+@item @tt{ciaolang}: alias for @tt{https://ciao-lang.org/playground}
+@item @tt{local}: alias for @tt{http://localhost:8001/playground}
+  (development local playground, see @tt{ciao-serve-mt})
+@end{itemize}
+".
+pgloc(ciaolang).
+pgloc(local).
+
+pg_url(ciaolang, 'https://ciao-lang.org/playground').
+pg_url(local, 'http://localhost:8001/playground').
+
+:- export(openpg/1).
+:- pred openpg(PGLoc) # "Open a new Ciao Playground".
+openpg(PGLoc) :-
+    openpg(PGLoc, '').
+
+:- export(openpg/2).
+:- pred openpg(PGLoc, Path) # "Open a Ciao Playground from the
+   specified location".
+
+openpg(PGLoc, Path) :-
+    ( pg_url(PGLoc, URL) -> true
+    ; throw(error(bad_pgloc, openpg/2))
+    ),
+    ( Path = '' ->
+        opendoc(URL)
+    ; PGLoc = local ->
+        Path1 = ~fixed_absolute_file_name(Path, '.'),
+        path_split(Path1, _, Name),
+        create_site_symlink(Path1, Name),
+        URL2 = ~atom_concat(URL, ~atom_concat('#/tmp/', Name)),
+        opendoc(URL2)
+    ; throw(error(unsupported_path, openpg/2))
+    ).
+
+% ---------------------------------------------------------------------------
+% TODO: implement a better way; use FileSystem API?
+
+:- use_module(library(pathnames)).
+:- use_module(library(system),[copy_file/3]).
+:- use_module(library(system_extra),[mkpath/1]).
+
+:- use_module(ciaobld(config_common), [site_root_dir/1]).
+
+% Create symbolic link under site tmp
+create_site_symlink(OrigPath, DestName) :-
+    SiteDir = ~site_root_dir,
+    TmpSite = ~path_concat(SiteDir, 'tmp'),
+    mkpath(TmpSite),
+    DestPath = ~path_concat(TmpSite, DestName),
+    copy_file(OrigPath, DestPath, [overwrite, symlink]).