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| 1 | +/* |
| 2 | + * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. |
| 3 | + * |
| 4 | + * Licensed under the Apache License, Version 2.0 (the "License"). |
| 5 | + * You may not use this file except in compliance with the License. |
| 6 | + * You may obtain a copy of the License at |
| 7 | + * |
| 8 | + * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | + * |
| 10 | + * Unless required by applicable law or agreed to in writing, software |
| 11 | + * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | + * See the License for the specific language governing permissions and |
| 14 | + * limitations under the License. |
| 15 | + */ |
| 16 | + |
| 17 | +-- complain if script is sourced in psql, rather than via CREATE EXTENSION |
| 18 | +\echo Use "CREATE EXTENSION pg_tle" to load this file. \quit |
| 19 | + |
| 20 | +CREATE OR REPLACE FUNCTION pgtle.uninstall_extension(extname text) |
| 21 | +RETURNS boolean |
| 22 | +SET search_path TO 'pgtle' |
| 23 | +AS $_pgtleie_$ |
| 24 | + DECLARE |
| 25 | + ctlname text; |
| 26 | + sqlpattern text; |
| 27 | + searchctl text; |
| 28 | + searchsql text; |
| 29 | + dropsql text; |
| 30 | + pgtlensp text := 'pgtle'; |
| 31 | + func text; |
| 32 | + existsvar record; |
| 33 | + BEGIN |
| 34 | + |
| 35 | + -- the control function is named exactly '<extname>.control' |
| 36 | + ctlname := extname || '.control'; |
| 37 | + /* |
| 38 | + * Script functions are named '<extname>--<version>.sql' and |
| 39 | + * '<extname>--<from>--<to>.sql'. Match them with a regex anchored on the |
| 40 | + * '--' that follows the name: '^<extname>--<anything>.sql$'. '--' cannot |
| 41 | + * occur in an extension name, so a prefix-named sibling like '<extname>_x' |
| 42 | + * cannot match. regexp_replace() backslash-escapes any regex |
| 43 | + * metacharacters in extname so it is matched literally. |
| 44 | + */ |
| 45 | + sqlpattern := '^' || regexp_replace(extname, '([\\^$.|?*+(){}\[\]-])', '\\\1', 'g') || '--.*\.sql$'; |
| 46 | + searchctl := 'SELECT proname FROM pg_catalog.pg_proc p JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace WHERE proname OPERATOR(pg_catalog.=) $1 AND n.nspname = $2'; |
| 47 | + searchsql := 'SELECT proname FROM pg_catalog.pg_proc p JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace WHERE proname OPERATOR(pg_catalog.~) $1 AND n.nspname = $2'; |
| 48 | + |
| 49 | + EXECUTE searchctl USING ctlname, pgtlensp INTO existsvar; |
| 50 | + IF existsvar IS NULL THEN |
| 51 | + RAISE EXCEPTION 'Extension % does not exist', extname USING ERRCODE = 'no_data_found'; |
| 52 | + ELSE |
| 53 | + FOR func IN EXECUTE searchctl USING ctlname, pgtlensp LOOP |
| 54 | + dropsql := format('DROP FUNCTION %I()', func); |
| 55 | + EXECUTE dropsql; |
| 56 | + END LOOP; |
| 57 | + END IF; |
| 58 | + |
| 59 | + EXECUTE searchsql USING sqlpattern, pgtlensp INTO existsvar; |
| 60 | + IF existsvar IS NULL THEN |
| 61 | + RAISE WARNING 'Extension % has an anomaly; control function exists, but no sql commands function exists', extname; |
| 62 | + ELSE |
| 63 | + FOR func IN EXECUTE searchsql USING sqlpattern, pgtlensp LOOP |
| 64 | + dropsql := format('DROP FUNCTION %I()', func); |
| 65 | + EXECUTE dropsql; |
| 66 | + END LOOP; |
| 67 | + END IF; |
| 68 | + |
| 69 | + RETURN true; |
| 70 | + END; |
| 71 | +$_pgtleie_$ |
| 72 | +LANGUAGE plpgsql STRICT; |
| 73 | + |
| 74 | +-- uninstall an extension for a specific version |
| 75 | +CREATE OR REPLACE FUNCTION pgtle.uninstall_extension(extname text, version text) |
| 76 | +RETURNS boolean |
| 77 | +SET search_path TO 'pgtle' |
| 78 | +AS $_pgtleie_$ |
| 79 | + DECLARE |
| 80 | + ctlname text; |
| 81 | + sqlpattern text; |
| 82 | + countverssql text; |
| 83 | + vers_count bigint; |
| 84 | + defaultversql text; |
| 85 | + defaultver text; |
| 86 | + searchctl text; |
| 87 | + searchsql text; |
| 88 | + dropsql text; |
| 89 | + pgtlensp text := 'pgtle'; |
| 90 | + func_available_vers text := 'available_extension_versions()'; |
| 91 | + func_available_ext text := 'available_extensions()'; |
| 92 | + func text; |
| 93 | + esc_ext text; |
| 94 | + esc_ver text; |
| 95 | + BEGIN |
| 96 | + -- regex-escape name and version so any metacharacters are matched literally |
| 97 | + esc_ext := regexp_replace(extname, '([\\^$.|?*+(){}\[\]-])', '\\\1', 'g'); |
| 98 | + esc_ver := regexp_replace(version, '([\\^$.|?*+(){}\[\]-])', '\\\1', 'g'); |
| 99 | + ctlname := extname || '.control'; |
| 100 | + /* |
| 101 | + * Match this version's install script ('<ext>--<ver>.sql') and every |
| 102 | + * update-path script that uses the version as a token, via the alternation |
| 103 | + * '(<ver> | .*--<ver> | <ver>--.*)': |
| 104 | + * <ver> -> '<ext>--<ver>.sql' (the version install script) |
| 105 | + * .*--<ver> -> '<ext>--<from>--<ver>.sql' (an update into this version) |
| 106 | + * <ver>--.* -> '<ext>--<ver>--<to>.sql' (an update out of this version) |
| 107 | + * '--' separates the tokens and cannot occur within a name or a version. |
| 108 | + */ |
| 109 | + sqlpattern := '^' || esc_ext || '--(' || esc_ver || '|.*--' || esc_ver || '|' || esc_ver || '--.*)\.sql$'; |
| 110 | + countverssql := format('SELECT COUNT(*) FROM %s.%s WHERE name = $1', pgtlensp, func_available_vers); |
| 111 | + defaultversql := format('SELECT default_version FROM %s.%s WHERE name = $1', pgtlensp, func_available_ext); |
| 112 | + searchctl := 'SELECT proname FROM pg_catalog.pg_proc p JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace WHERE proname OPERATOR(pg_catalog.=) $1 AND n.nspname = $2'; |
| 113 | + searchsql := 'SELECT proname FROM pg_catalog.pg_proc p JOIN pg_catalog.pg_namespace n ON n.oid = p.pronamespace WHERE proname OPERATOR(pg_catalog.~) $1 AND n.nspname = $2'; |
| 114 | + |
| 115 | + EXECUTE countverssql USING extname INTO vers_count; |
| 116 | + EXECUTE defaultversql USING extname INTO defaultver; |
| 117 | + |
| 118 | + IF vers_count > 1 THEN |
| 119 | + -- if multiple versions exist and this is the default version, don't uninstall |
| 120 | + IF version = defaultver THEN |
| 121 | + RAISE EXCEPTION 'Can not uninstall default version of extension %, use set_default_version to update the default to another available version and retry', extname; |
| 122 | + ELSE |
| 123 | + -- remove the specified version sql file function only, don't remove control file function |
| 124 | + FOR func IN EXECUTE searchsql USING sqlpattern, pgtlensp LOOP |
| 125 | + dropsql := format('DROP FUNCTION %I()', func); |
| 126 | + EXECUTE dropsql; |
| 127 | + END LOOP; |
| 128 | + END IF; |
| 129 | + ELSE |
| 130 | + -- check that the specified version matches the only version that exists |
| 131 | + -- if it does then uninstall the extension completely |
| 132 | + -- if it doesn't then don't uninstall anything to avoid accidental uninstall |
| 133 | + IF version = defaultver THEN |
| 134 | + FOR func IN EXECUTE searchctl USING ctlname, pgtlensp LOOP |
| 135 | + dropsql := format('DROP FUNCTION %I()', func); |
| 136 | + EXECUTE dropsql; |
| 137 | + END LOOP; |
| 138 | + FOR func IN EXECUTE searchsql USING sqlpattern, pgtlensp LOOP |
| 139 | + dropsql := format('DROP FUNCTION %I()', func); |
| 140 | + EXECUTE dropsql; |
| 141 | + END LOOP; |
| 142 | + ELSE |
| 143 | + RAISE EXCEPTION 'Version % of extension % is not installed and therefore can not be uninstalled', extname, version; |
| 144 | + END IF; |
| 145 | + END IF; |
| 146 | + |
| 147 | + RETURN TRUE; |
| 148 | + END; |
| 149 | +$_pgtleie_$ |
| 150 | +LANGUAGE plpgsql STRICT; |
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