mirror/postgresql
2
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2025-03-01 19:45:33 +08:00
Code Issues Packages Projects Releases Wiki Activity

Change the naming convention for extension files to use double dashes.

Browse Source 
This allows us to have an unambiguous rule for deconstructing the names
of script files and secondary control files, without having to forbid
extension and version names from containing any dashes.  We do have to
forbid them from containing double dashes or leading/trailing dashes,
but neither restriction is likely to bother anyone in practice.
Per discussion, this seems like a better solution overall than the
original design.
This commit is contained in:
Tom Lane 2011-02-13 13:03:41 -05:00
parent 5569ae52ae
commit 27d5d7ab10
2 changed files with 113 additions and 39 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
doc/src/sgml/extend.sgml
View File

@ -368,8 +368,8 @@
installation's <literal>SHAREDIR/extension</literal> directory. There
must also be at least one <acronym>SQL</> script file, which follows the
naming pattern
<literal><replaceable>extension</>-<replaceable>version</>.sql</literal>
(for example, <literal>foo-1.0.sql</> for version <literal>1.0</> of
<literal><replaceable>extension</>--<replaceable>version</>.sql</literal>
(for example, <literal>foo--1.0.sql</> for version <literal>1.0</> of
extension <literal>foo</>). By default, the script file(s) are also
placed in the <literal>SHAREDIR/extension</literal> directory; but the
control file can specify a different directory for the script file(s).
@ -378,7 +378,7 @@
<para>
The file format for an extension control file is the same as for the
<filename>postgresql.conf</> file, namely a list of
<replaceable>parameter-name</> <literal>=</> <replaceable>value</>
<replaceable>parameter_name</> <literal>=</> <replaceable>value</>
assignments, one per line. Blank lines and comments introduced by
<literal>#</> are allowed. Be sure to quote any value that is not
a single word or number.
@ -477,7 +477,7 @@
In addition to the primary control file
<literal><replaceable>extension</>.control</literal>,
an extension can have secondary control files named in the style
<literal><replaceable>extension</>-<replaceable>version</>.control</literal>.
<literal><replaceable>extension</>--<replaceable>version</>.control</literal>.
If supplied, these must be located in the script file directory.
Secondary control files follow the same format as the primary control
file. Any parameters set in a secondary control file override the
@ -671,15 +671,15 @@ SELECT pg_catalog.pg_extension_config_dump('my_config', 'WHERE NOT standard_entr
dynamically from one version to the next, you should provide
<firstterm>update scripts</> that make the necessary changes to go from
one version to the next. Update scripts have names following the pattern
<literal><replaceable>extension</>-<replaceable>oldversion</>-<replaceable>newversion</>.sql</literal>
(for example, <literal>foo-1.0-1.1.sql</> contains the commands to modify
<literal><replaceable>extension</>--<replaceable>oldversion</>--<replaceable>newversion</>.sql</literal>
(for example, <literal>foo--1.0--1.1.sql</> contains the commands to modify
version <literal>1.0</> of extension <literal>foo</> into version
<literal>1.1</>).
</para>
<para>
Given that a suitable update script is available, the command
<command>ALTER EXTENSION ... UPDATE</> will update an installed extension
<command>ALTER EXTENSION UPDATE</> will update an installed extension
to the specified new version. The update script is run in the same
environment that <command>CREATE EXTENSION</> provides for installation
scripts: in particular, <varname>search_path</> is set up in the same
@ -712,7 +712,7 @@ SELECT pg_catalog.pg_extension_config_dump('my_config', 'WHERE NOT standard_entr
class="parameter">old_version</> option, which causes it to not run the
normal installation script for the target version, but instead the update
script named
<literal><replaceable>extension</>-<replaceable>old_version</>-<replaceable>target_version</>.sql</literal>.
<literal><replaceable>extension</>--<replaceable>old_version</>--<replaceable>target_version</>.sql</literal>.
The choice of the dummy version name to use as <replaceable
class="parameter">old_version</> is up to the extension author, though
<literal>unpackaged</> is a common convention. If you have multiple
@ -723,7 +723,7 @@ SELECT pg_catalog.pg_extension_config_dump('my_config', 'WHERE NOT standard_entr
<para>
<command>ALTER EXTENSION</> is able to execute sequences of update
script files to achieve a requested update. For example, if only
<literal>foo-1.0-1.1.sql</> and <literal>foo-1.1-2.0.sql</> are
<literal>foo--1.0--1.1.sql</> and <literal>foo--1.1--2.0.sql</> are
available, <command>ALTER EXTENSION</> will apply them in sequence if an
update to version <literal>2.0</> is requested when <literal>1.0</> is
currently installed.
@ -734,11 +734,13 @@ SELECT pg_catalog.pg_extension_config_dump('my_config', 'WHERE NOT standard_entr
of version names: for example, it does not know whether <literal>1.1</>
follows <literal>1.0</>. It just matches up the available version names
and follows the path that requires applying the fewest update scripts.
(A version name can actually be any string that doesn't contain
<literal>--</> or leading or trailing <literal>-</>.)
</para>
<para>
Sometimes it is useful to provide <quote>downgrade</> scripts, for
example <literal>foo-1.1-1.0.sql</> to allow reverting the changes
example <literal>foo--1.1--1.0.sql</> to allow reverting the changes
associated with version <literal>1.1</>. If you do that, be careful
of the possibility that a downgrade script might unexpectedly
get applied because it yields a shorter path. The risky case is where
@ -761,7 +763,7 @@ SELECT pg_catalog.pg_extension_config_dump('my_config', 'WHERE NOT standard_entr
</para>
<para>
The script file <filename>pair-1.0.sql</> looks like this:
The script file <filename>pair--1.0.sql</> looks like this:
<programlisting><![CDATA[
CREATE TYPE pair AS ( k text, v text );
@ -803,7 +805,7 @@ relocatable = true
<programlisting>
EXTENSION = pair
DATA = pair-1.0.sql
DATA = pair--1.0.sql
PG_CONFIG = pg_config
PGXS := $(shell $(PG_CONFIG) --pgxs)
@ -860,7 +862,7 @@ include $(PGXS)
<programlisting>
MODULES = isbn_issn
EXTENSION = isbn_issn
DATA_built = isbn_issn-1.0.sql
DATA = isbn_issn--1.0.sql
DOCS = README.isbn_issn
PG_CONFIG = pg_config

124
src/backend/commands/extension.c
View File

@ -57,9 +57,6 @@
bool creating_extension = false;
Oid CurrentExtensionObject = InvalidOid;
/* Character that separates extension & version names in a script filename */
#define EXT_VERSION_SEP '-'
/*
* Internal data structure to hold the results of parsing a control file
*/
@ -225,9 +222,42 @@ get_extension_schema(Oid ext_oid)
static void
check_valid_extension_name(const char *extensionname)
{
int namelen = strlen(extensionname);
/*
* No directory separators (this is sufficient to prevent ".." style
* attacks).
* Disallow empty names (the parser rejects empty identifiers anyway,
* but let's check).
*/
if (namelen == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid extension name: \"%s\"", extensionname),
errdetail("Extension names must not be empty.")));
/*
* No double dashes, since that would make script filenames ambiguous.
*/
if (strstr(extensionname, "--"))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid extension name: \"%s\"", extensionname),
errdetail("Extension names must not contain \"--\".")));
/*
* No leading or trailing dash either. (We could probably allow this,
* but it would require much care in filename parsing and would make
* filenames visually if not formally ambiguous. Since there's no
* real-world use case, let's just forbid it.)
*/
if (extensionname[0] == '-' || extensionname[namelen - 1] == '-')
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid extension name: \"%s\"", extensionname),
errdetail("Extension names must not begin or end with \"-\".")));
/*
* No directory separators either (this is sufficient to prevent ".."
* style attacks).
*/
if (first_dir_separator(extensionname) != NULL)
ereport(ERROR,
@ -239,16 +269,39 @@ check_valid_extension_name(const char *extensionname)
static void
check_valid_version_name(const char *versionname)
{
/* No separators --- would risk confusion of install vs update scripts */
if (strchr(versionname, EXT_VERSION_SEP))
int namelen = strlen(versionname);
/*
* Disallow empty names (we could possibly allow this, but there seems
* little point).
*/
if (namelen == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid extension version name: \"%s\"", versionname),
errdetail("Version names must not contain the character \"%c\".",
EXT_VERSION_SEP)));
errdetail("Version names must not be empty.")));
/*
* No directory separators (this is sufficient to prevent ".." style
* attacks).
* No double dashes, since that would make script filenames ambiguous.
*/
if (strstr(versionname, "--"))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid extension version name: \"%s\"", versionname),
errdetail("Version names must not contain \"--\".")));
/*
* No leading or trailing dash either.
*/
if (versionname[0] == '-' || versionname[namelen - 1] == '-')
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid extension version name: \"%s\"", versionname),
errdetail("Version names must not begin or end with \"-\".")));
/*
* No directory separators either (this is sufficient to prevent ".."
* style attacks).
*/
if (first_dir_separator(versionname) != NULL)
ereport(ERROR,
@ -336,8 +389,8 @@ get_extension_aux_control_filename(ExtensionControlFile *control,
scriptdir = get_extension_script_directory(control);
result = (char *) palloc(MAXPGPATH);
snprintf(result, MAXPGPATH, "%s/%s%c%s.control",
scriptdir, control->name, EXT_VERSION_SEP, version);
snprintf(result, MAXPGPATH, "%s/%s--%s.control",
scriptdir, control->name, version);
pfree(scriptdir);
@ -355,12 +408,11 @@ get_extension_script_filename(ExtensionControlFile *control,
result = (char *) palloc(MAXPGPATH);
if (from_version)
snprintf(result, MAXPGPATH, "%s/%s%c%s%c%s.sql",
scriptdir, control->name, EXT_VERSION_SEP, from_version,
EXT_VERSION_SEP, version);
snprintf(result, MAXPGPATH, "%s/%s--%s--%s.sql",
scriptdir, control->name, from_version, version);
else
snprintf(result, MAXPGPATH, "%s/%s%c%s.sql",
scriptdir, control->name, EXT_VERSION_SEP, version);
snprintf(result, MAXPGPATH, "%s/%s--%s.sql",
scriptdir, control->name, version);
pfree(scriptdir);
@ -426,7 +478,7 @@ parse_extension_control_file(ExtensionControlFile *control,
if (version)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("parameter \"%s\" cannot be set in a per-version extension control file",
errmsg("parameter \"%s\" cannot be set in a secondary extension control file",
item->name)));
control->directory = pstrdup(item->value);
@ -436,7 +488,7 @@ parse_extension_control_file(ExtensionControlFile *control,
if (version)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("parameter \"%s\" cannot be set in a per-version extension control file",
errmsg("parameter \"%s\" cannot be set in a secondary extension control file",
item->name)));
control->default_version = pstrdup(item->value);
@ -907,16 +959,18 @@ get_ext_ver_list(ExtensionControlFile *control)
/* ... matching extension name followed by separator */
if (strncmp(de->d_name, control->name, extnamelen) != 0 ||
de->d_name[extnamelen] != EXT_VERSION_SEP)
de->d_name[extnamelen] != '-' ||
de->d_name[extnamelen + 1] != '-')
continue;
/* extract version names from 'extname-something.sql' filename */
vername = pstrdup(de->d_name + extnamelen + 1);
/* extract version names from 'extname--something.sql' filename */
vername = pstrdup(de->d_name + extnamelen + 2);
*strrchr(vername, '.') = '\0';
vername2 = strchr(vername, EXT_VERSION_SEP);
vername2 = strstr(vername, "--");
if (!vername2)
continue; /* it's not an update script */
*vername2++ = '\0';
*vername2 = '\0'; /* terminate first version */
vername2 += 2; /* and point to second */
/* Create ExtensionVersionInfos and link them together */
evi = get_ext_ver_info(vername, &evi_list);
@ -979,6 +1033,20 @@ identify_update_path(ExtensionControlFile *control,
evi2->distance = newdist;
evi2->previous = evi;
}
else if (newdist == evi2->distance &&
evi2->previous != NULL &&
strcmp(evi->name, evi2->previous->name) < 0)
{
/*
* Break ties in favor of the version name that comes first
* according to strcmp(). This behavior is undocumented and
* users shouldn't rely on it. We do it just to ensure that
* if there is a tie, the update path that is chosen does not
* depend on random factors like the order in which directory
* entries get visited.
*/
evi2->previous = evi;
}
}
}
@ -1251,7 +1319,7 @@ CreateExtension(CreateExtensionStmt *stmt)
requiredExtensions);
/*
* Apply any comment on extension
* Apply any control-file comment on extension
*/
if (control->comment != NULL)
CreateComments(extensionOid, ExtensionRelationId, 0, control->comment);
@ -1544,6 +1612,10 @@ pg_available_extensions(PG_FUNCTION_ARGS)
extname = pstrdup(de->d_name);
*strrchr(extname, '.') = '\0';
/* ignore it if it's an auxiliary control file */
if (strstr(extname, "--"))
continue;
control = read_extension_control_file(extname);
memset(values, 0, sizeof(values));